legal and economic aspects of crops selection for

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LEGAL AND ECONOMIC ASPECTS OF CROPS SELECTION FOR

PHYTOREMEDIATION PURPOSES AND THE PRODUCTION OF BIOFUEL

PROF. DR. BERNARD VANHEUSDEN (PROMOTER)

MS. MARIANNE HOPPENBROUWERS

MS. NELE WITTERS

In cooperation with:

PROF. DR. JACO VANGRONSVELD

PROF. DR. THEO THEWYS

PROF. DR. STEVEN VAN PASSEL

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CONTENT

CONTENT .......................................................................................................................................2

FOREWORD....................................................................................................................................5

A. LEGAL ASPECTS ......................................................................................................................7

I. SELECTING THE CROPS AND SOIL MANAGEMENT ............................................................................7

1. Introduction ..............................................................................................................................7

2. Plant characteristics ..................................................................................................................7

2.1 Invasive and exotic plants ..................................................................................................8

2.1.1 General ........................................................................................................................8

2.1.2 Local regulations .........................................................................................................9

2.2 Genetically Modified Plants (GM plant) ..........................................................................10

2.2.1 General ......................................................................................................................10

2.2.2 Local regulations .......................................................................................................12

3. Soil management ....................................................................................................................14

3.1 The importance of an international and national regulation.............................................14

3.1.1 An international challenge.........................................................................................14


3.2 Phytoremediation: the difference between stabilization and extraction ...........................17

3.2.1 Stabilization ...............................................................................................................18

3.2.2 Extraction ..................................................................................................................20


II. GROWING AND HARVESTING THE CROPS .....................................................................................25

1. Introduction ............................................................................................................................25

2. Growing the crops ..................................................................................................................26

2.1 The crops are planted........................................................................................................26

2.2 Fertilizing .........................................................................................................................27

2.2.1 General ......................................................................................................................27

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2.2.2 The use of specific fertilizers ....................................................................................28

Local regulations ................................................................................................................31

2.3 Plant protection.................................................................................................................32

Local regulations ................................................................................................................33

3. Harvesting the crops ...............................................................................................................34

3.1 The plants are contaminated .............................................................................................34

3.2 Waste or not waste............................................................................................................36

Local rules ..........................................................................................................................38

3.3 Should biomass be registered under REACH?.................................................................39

III. BIBLIOGRAPHY ..........................................................................................................................40

1. Legislation ..............................................................................................................................40

2. Literature ................................................................................................................................42

B. ECONOMIC ASPECTS ............................................................................................................46

I. ECONOMIC MODEL BASED ON LITERATURE REVIEW......................................................................46

1. Conceptual framework ...........................................................................................................46

1.1 What Rejuvenate 1 started… ............................................................................................46

1.2 … and Rejuvenate 2 continues .........................................................................................48

1.3 Decision tool specifics (work package 5).........................................................................50

1.3.1 General outline ..........................................................................................................50

1.3.2 Model specifics..........................................................................................................51

2. Literature review ....................................................................................................................52

2.1 Phytoremediation..............................................................................................................52

2.1.1 Remediation duration ................................................................................................53

2.1.2 Hyperaccumulators ....................................................................................................55

2.1.3 Biomass producing crops ..........................................................................................56

2.2 Biomass for energy ...........................................................................................................57

2.3 Cost Benefit Analysis (CBA) ...........................................................................................58

2.3.1 Theory........................................................................................................................58

2.3.2 Externalities ...............................................................................................................60

2.3.3 Non-economic valuation ...........................................................................................62

2.3.4 Sustainability .............................................................................................................62

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II. ECONOMY, ENERGY AND WASTE DISPOSAL .................................................................................64

1. Introduction ............................................................................................................................64

1.1 Model outline....................................................................................................................64

1.2 Case study: Campine region (BE) ....................................................................................65

2. Private costs and benefits .......................................................................................................67

3. Biomass for energy .................................................................................................................72

3.1 Assumptions .....................................................................................................................73

3.2 Fossil energy input for biomass production .....................................................................74

3.3 From biomass to gross energy ..........................................................................................75

3.4 Effect of contaminants on energy production potential ...................................................78

3.4.1 General ......................................................................................................................78

3.4.2 Case study..................................................................................................................79

3.5 From gross energy content to net thermal, electric, and mechanical energy ...................80

3.6 Contamination in rest product-energetic impact ..............................................................81

3.6.1 General ......................................................................................................................81

3.6.2 Case study..................................................................................................................82

3.7 Overview ..........................................................................................................................82

3.7.1 General ......................................................................................................................82

3.7.2 Case study..................................................................................................................84

3.8 CO2 abatement (case study)..............................................................................................87

4. Contamination in rest product - economic impact .................................................................90

4.1 General .............................................................................................................................90

4.2 Case study.........................................................................................................................90

5. Integration...............................................................................................................................92

6. Conclusion ..............................................................................................................................93

III. BIBLIOGRAPHY ..........................................................................................................................94

1. Legislation ..............................................................................................................................94

2. Literature ................................................................................................................................94

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FOREWORD

This report frames within the European project Rejuvenate 2, granted by the Snowman network.

Rejuvenate 2 has started in the beginning of 2010 and has a duration of three years. The goal of

the project is to work out concrete approaches to use contaminated soils for the production of

biomass. The project includes, besides desk top studies, field experiments. With regard to the

biomass, the project mainly focuses on biomass that can be used to produce biofuels. The project

researches whether the reuse of contaminated soils could become interesting again, and this from

an ecological as well as an economical perspective.

Rejuvenate 2 is based on Rejuvenate 1. In Rejuvenate 1 a model was established to steer the

decision making process to reuse marginal soils for non-food crops (decision support tool). The

aim of Rejuvenate 2 is to test on the basis of concrete case studies (field experiments) the

decision support tool and to come to a detailed tool that can be used later on for multiple types of

contaminated soils. The case studies take place in Sweden and in Romania. The economical

analysis is based on the results of an existing case study in Belgium, more specifically in the

Campine region.

On the basis of the tests, the aims of the project are i) to validate and optimise the decision

framework, ii) to provide detailed case studies for the reuse of contaminated soil for the

production of bio fuel crops, in particular secondary bio fuels, and iii) to expand the decision

support tool by applying and validating the tool in two new jurisdictions (Sweden and Romania).

The partners within the project are:

- Swedish Geotechnical Institute (SGI) (Sweden) (coordinator)

- Centre for Environmental Sciences (CMK), Hasselt University (Belgium)

- Bioclear (Netherlands)

- National Institute for Metals and Radioactive Resources (Romania)

The partners are each financed by governments/institutions within their own country.

This report discusses specifically the legal and economic aspects of crops selection for

phytoremediation purposes and the production of biofuel.

The report is based on four intermediary reports, which were discussed with the steering group

within the Flemish Public Waste Agency (OVAM) as well as with the other project partners.

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The structure of this report is as follows. In the first place, the report starts with a part on the

legal aspects (part A). This part follows the chronology in practice and is therefore divided in

two chapters, one on the selection of the crops and the management of the soil, and one on the

growing and the harvesting of the crops. Secondly, the report discusses the economic aspects

(part B). This part starts with the establishment of an economic model based on a detailed

literature review. Next, the report researches whether phytoremediation results in economically

optimal remediation strategies. The two parts end each time with an extensive bibliography.

The status of the legislation was followed until 1 May 2011.

The research was executed by a multidisciplinary team of lawyers and economists of Hasselt

University. Within the university they are members of the Centre for Environmental Sciences

(CMK), a research institute in which they cooperate with biologists and chemists.

The research was supervised by Prof. dr. Bernard Vanheusden. Marianne Hoppenbrouwers (for

the legal part) and Nele Witters (for the economic part) worked as fulltime researchers on the

study. Prof. dr. Jaco Vangronsveld, Prof. dr. Theo Thewys and Prof. dr. Steven Van Passel also

cooperated in the research by reading texts and giving advice.

The research was financed by the OVAM. The project team would like to thank the OVAM very

much. We would also like to thank all the members of the steering group within the OVAM, and

in particular Ms. Ellen Luyten, for their valuable input and advice.

Prof. dr. Bernard Vanheusden

4 October 2011

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A. LEGAL ASPECTS

I. SELECTING THE CROPS AND SOIL MANAGEMENT

1. Introduction

For the analysis of the legal aspects we will be working on the basis of the Decision Support Tool

(DST) developed in the Rejuvenate 1 project. The decision making procedure identified in

Rejuvenate 1 starts with the explicit statement of the project objectives. Once the targets are

clear, the process is structured around four phases: the selection of the crop, the site suitability

and management, the economic, social and environmental value of the project, and the project

risks based on the status of the available technology, stakeholders views and the final business

plan.

This part on the legal aspects will try to follow the chronology of the decision making procedure.

However, the legal implications go across the different phases and are interlinked. Therefore,

where necessary, cross references between the different stages will be made.

This first chapter “Selecting the crops and soil management” focuses on international and

European legislation affecting crop selection and related aspects, namely plant selection, and on

soil management (including management of risks) in case of phytostabilization or

phytoextraction. In the following paragraph plant characteristics, namely the issues of invasive

and exotic plants and of genetically modified organisms, are discussed. The second paragraph

considers the implications of soil management both for stabilization and extraction, for example:

amendments to the soil, bioavailability of pollutants and plant protection.

2. Plant characteristics

The first question to be asked is whether there are any plant species that are not legally allowed to

be used in phytoremediation? Besides purely scientific and utilitarian reasons for selecting crops,

one should ensure that the selected species is legally allowed to be planted on the site. Several

international/European agreements and regulations have an impact on this. Following is an

overview of the topics relevant for the Rejuvenate 2 project. However, for each real, individual

project an assessment on the basis of site location and local circumstances remains necessary.

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Table I: relevant regulation plants/crops

The Convention on Biological Diversity, 1993

The International Plant Protection Convention (IPPC), 1951 – revised in 1997

Convention on the Conservation of European Wildlife and Natural Habitats (Bern Convention),

1979

Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild

fauna and flora (Habitat Directive)

Council Directive 2000/29/EC of 8 May 2000 on protective measures against the introduction

into the Community of organisms harmful to plants or plant products and against their spread

within the Community

Directive 2001/18/EC of the European Parliament and of the Council of 12 March 2001 on the

deliberate release into the environment of genetically modified organisms and repealing Council

Directive 90/220/EEC

Directive 2004/35/CE of the European Parliament and of the Council of 21 April 2004 on

environmental liability with regard to the prevention and remedying of environmental damage

2.1 Invasive and exotic plants

2.1.1 General

Invasive and exotic plants are a danger to biodiversity. Recently, Florida experienced this with

Arundo donax, a large clumping grass that produces a lot of biomass usable as bioenergy

feedstock. The plant is also used in phytoremediation for its uptake of arsenic1, mercury and

cadmium2. Giant reed alters the hydrology and displaces native species.3 It is known to be

destructive to fish and amphibian habitats and to seriously harm habitats for rare species by its

potential to reproduce by fragmentation of rhizomes and production of new roots from stems.4 It

forms large clumps of grass in riparian habitats. Meanwhile, Arundo donax has been imported in

all regions across the globe, sometimes only for decoration purposes, but frequently for

phytoremediation or the production of biomass. Research on genetically modifying the grass for

phytoremediation purposes is ongoing.

Already in 1993 the parties to the Convention on Biological Diversity (CDB) committed

themselves to protect their ecosystems, habitats or species against the threats posed by alien

species.5 The European Habitat Directive6 translates the CDB into an obligation for the Member

1 www.ncbi.nlm.nih.gov/pubmed/20363125.

2 www.ncbi.nlm.nih.gov/pubmed/16110677.

3 www.issg.org/database/species/ecology.asp?si=112.

4 FLORIDA NATIVE PLANT SOCIETY, Policy statement on Arundo donax, p. 1,

http://www.fnps.org/committees/policy/pdfs/policyarundo_policy_s tatement1.pdf, last visited on 6 June 2010. 5 Article 8, h of the Convention on Biological Diversity (CBD).

http://europa.eu.int/smartapi/cgi/sga_doc?smartapi%21celexapi%21prod%21CELEXnumdoc&lg=EN&numdoc=31992L0043&model=guichett


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States. The principle is that the Member States should “ensure that the deliberate introduction

into the wild of any species which is not native to their territory is regulated so as not to

prejudice natural habitats within their natural range or the wild native fauna and flora and, if

they consider it necessary, prohibit such introduction.”7

This principle and the other obligations in the directive should be translated into national

regulations. When selecting a crop it is advisable to check the national and local rules relating to

the Habitat Directive. Examples of non-native plants, commonly used for phytoremediation, that

would fall under article 22, b of the Habitat Directive are: Miscanthus, Switch grass and Arundo

donax. If on the site plants and animal life is present, it is also useful to check on the eventual

presence of protected species.

Another important Convention concerning plant selection is the “International Plant Protection

Convention”8 (IPPC). Following an obligation stipulated in this convention, the European and

Mediterranean Plant Protection Organization (EPPO) was founded in 1951. EPPO is an

intergovernmental organization with at this moment 50 members, covering almost all countries of

Europe. One of the important activities of the organization is to compile lists with invasive plants

and pests. These lists are publicly available on their website.9

Consultation of the database showed that some plants proposed in the Rejuvenate 2 project for

phytoremediation are on these lists. For example: several species of Salix and two Helianthus

species are considered as invasive.

When selecting a crop for a phytoremediation project, it is advisable to consult the database

before the final decision. Additional and specific local information can be requested from the

National Plant Protection Organizations, of which the addresses can also be found on the website

of EPPO.

2.1.2 Local regulations10

Belgium, the Netherlands, Sweden and Romania are also bound by the “Directive on Protective

Measures against Introduction of Organisms harmful to plants or plant products and against their

Spread within the Community”.11 Specifically Annex III of the directive is relevant in relation to

6 Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora

(Habitat Directive), O.J. 22 July 1992, L 206, consolidated version 2007,

ec.europa.eu/environment/nature/legislation/habitatsdirective/index_en.htm. 7 Article 22 (b) of the Habitat Directive.

8 Article IX of the International Plant Protection Convention (IPPC).

9 www.eppo.org, then go to DATABASES; the download instructions and links for both the lists of plants as a

manual are on that page, last visited on 5 June 2010. 10

“Local regulations” refers to the rules in the first line participants in Rejuvenate 2: Belgium, Netherlands, Romania

and Sweden. 11

Council Directive 2000/29/EC of 8 May 2000 on protective measures against the introduction into the Community

of organisms harmful to plants or plant products and against their spread within the Community, O.J. 10 July 2000, L


http://www.eppo.org/

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phytoremediation. This annex contains a list of plants of which the introduction in the European

Community is not allowed in general or in protected zones.

2.2 Genetically Modified Plants (GM plant)

2.2.1 General

Like with everything, there are also two sides on genetic modification of organisms (GMO).

Increasing the resilience of plants to abiotic stress, like metal contaminants, makes it possible to

use these plants for phytoremediation. Improve the uptake of contaminants by the green and

harvestable parts of plants or promote the immobilization capacity of the roots are clearly

beneficial in the remediation process. Salix plants (on our list of candidates) were, for example,

inoculated with genetically modified Psuedomonas fluorescens enhancing the biodegradation of

PCBs.12

On the other hand there exists quite some uncertainty and lack of knowledge on different aspects

of genetic modification. Soils are some of the most complex habitats on earth, with one gram of

agricultural or forest soil from temperate regions containing thousands of species. Given this

complexity, the impact of genetically modified plants on soil systems is not well understood.13

By consequence the question is raised if we can take these risks?14 Moreover, genetically

modifying a plant to better cope with environmental stress could lead to this plant becoming

invasive, potentially resulting in a loss of biodiversity.

The implications of using genetically modified crops should be carefully considered before

selecting the plant for a project. Besides the impact of current GMO regulation in Europe, the

public opinion is not in favour of these plants and the costs to comply with the rules are also not

to be neglected.

Is the use of GMOs forbidden in Europe?

169, consolidated version 14 April 2006, http://eur-lex.europa.eu/LexUriServ/site/en/consleg/2000/L/02000L0029-

20060414-en.pdf. 12

AGUIRRE DE CARCER D., MARTIN M. e.a. The introduction of genetically modified microorganisms designed

for rhizoremediation induces changes on native bacteria in the rizosphere but not in the surrounding soil, The ISME

Journal, 2007, 1, p 215, http://www.nature.com/ismej/journal/v1/n3/full/is mej200727a.html, last visited on 5 June

2010. 13

The potential environmental, cultural and socio-economic impacts of genetically modified trees, Conference on

Biological Diversity, March 2008, UNEP/CBD/COP/9/INF/27, p 20, www.cbd.int/doc/meetings/cop/cop-

09/information/cop-09-inf-27-en.pdf, last visited on 4 June 2010. 14

See also the paragraph on soil management.

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In case plants grown for phytoremediation and feedstock for biofuel are genetically modified,

Directive 2001/1815 on the deliberate release into the environment of GMOs is applicable. The

basic principle is that GMOs can only be put on the market if they are safe. Member States have

to take appropriate measures to guarantee this and thus to avoid adverse effects on human health

and the environment. Thereby the precautionary principle should be a decision criterion.16

The authorisation of a GM plant happens on an individual basis. The process requires testing of

the plant concerned to see if large scale cultivation could have an impact on the environment.

Of the plants on the project list (Sweden), genetically modified variations of maize, rapeseed and

sugar beet are at this moment authorized in Europe.17 But under European law Member States

can ban GMOs if they can justify the prohibition. This was not so long ago demonstrated in the

meeting of the European Environment Ministers.18 During the meeting of the European

Environment Ministers in Brussels, they voted against forcing Vienna and Budapest to allow US

biotech giant Monsanto’s MON810 GM maize grain to be grown in their countries. The ban is

thus upheld, notwithstanding the fact that this maize grain is fully authorized for food and feed,

plus for processing and import.19 Thus the debate on the accidental spread and adverse effects on

nature continues.20 The dissenting decisions of Member States are thereby based on the

obligation under article 4, 1 of the Directive on GMOs21 to ensure, in line with the precautionary

principle, that all appropriate measures are taken to avoid adverse effects on human health and

the environment resulting from the deliberate release or placing on the market of GMOs.

Article 6 of the Directive 2001/18 obliges any person who intends to release a GMO to notify the

Competent Authority of the Member State where that release will happen. The notification

consists of a technical dossier and an environmental risk assessment, including control,

monitoring, postrelease and waste treatment plans. The notifier may refer to information that was

already submitted by former notifiers, except when this information is considered to be

confidential. On the other hand Member States may accept a single notification if the release of

the same GMO is on the same site or on different sites for the same purpose and that within a

defined time period.22 In case modifications to the dossier are needed on the basis of new

information, the notifier is obliged to immediately take the necessary measures, including

15

Directive 2001/18/EC of the European Parliament and of the Council of 12 March 2001 on the deliberate release

into the environment of genetically modified organisms and repealing Council Directive 90/220/EEC, O.J. 17 April

2001, L 106. 16

Article 4, Directive 2001/18. 17

www.gmo-compass.org/eng/gmo/db/, last visited on 4 June 2010. 18

Brussels, March 2009. 19

http://www.gmo-compass.org/eng/gmo/db. 20

Austria, Hungary Allowed to Keep Ban on Genetically Modified Crops, Deutsche Welle, www.dw-

world.de/dw/article/0,,4068097,00.html, last visited 6 June 2010. 21

Article 4, 1 of Directive 2001/18. 22

Article 6 (4) Directive 2001/18.

http://www.gmo-compass.org/eng/gmo/db/

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information to the Competent Authority, in order to protect human health and the environment.23

Member States shall inform the public on any deliberate release of GMOs in their territory.

The conclusion is that all implications of using genetically modified crops should be carefully

considered before selecting such a plant for a project. There is not only the impact of current

GMO regulation in Europe, the public opinion is not in favour of these plants and the costs to

comply with the rules are not to be neglected. Thereby one should not only look to the

international aspect, but also investigate national rules.

2.2.2 Local regulations

Despite the difference between the traditional anti-GMO countries (such as France and Italy) and

the pro-GMO states (such as Spain, Germany, UK and Poland) a common proposal was accepted

by the European Parliament's environment committee on 12 April 2011. The proposal gives

Member States the choice whether to allow or to ban GMO cultivation on their territory.24

On 16 July 2009 the European Court of Justice decided that a national ban on the authorisation of

GMO seeds is incompatible with the European rules. This judgement showed the difficulty for

Member States to base a ban on health and environmental arguments.25

The actual proposal for a Regulation aims at providing a legal base to authorize Member States to

restrict or prohibit the cultivation of GMOs, although these might be authorized at EU level.26 A

national ban of GMOs should be based on arguments of public order in the face of popular

opposition to the technology, public morality grounds, such as religious or philosophical

concerns.27 In the proposal to the Parliament concerning the national authority to ban GMOs

environmental impacts were added to the list.28 EU governments including France, Britain and

Germany had already signalled their opposition to the Commission’s proposals, citing fears that

23

Article 8, 1, Directive 2001/18. 24

EURACTIV, MEPs back national freedom to ban GM crops, 13 April 2011,

http://www.euractiv.com/en/cap/meps-back-national-freedom-ban-gm-crops-news-503996 (accessed 13 April 2011). 25

Opinion of the European Economic and Social Committee on the Proposal for a Regulation of the European

Parliament and the Council amending Directive 2001/18/EC as regards the possibility for the M ember States to

restrict or prohibit the cultivation of GMOs in their territory, O.J. 19 February 2011, p. 53. 26

Proposal for a Regulation amending Directive 2001/18/EC as regards the possibility for the Member States to

restrict or prohibit the cultivation of GMOs in their territory, Brussels, 13 July 2010, COM(2010) 380 final, 15 p.,

http://www.europeanlawmonitor.org/legislation/2010/COM2010375text.pdf (accessed on 27 February 2011). 27

Point 5.1.3. 28

COUNCIL OF THE EUROPEAN UNION, Complementary considerations on legal issues on GMO cultivation

raised in the opinions of the legal services of the Council of European Union of 5 November 2010 and the Legal

service of the European Parliament of 17 November 2010, Brussels, 8 February 2011, document 16826/10 ADD1, p.

4.

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they breach world trade rules and could lead to legal challenges by biotech companies, exporting

countries and EU farmers.29

Belgium

The European directive30 2001/18/EC was transposed in the Belgian Royal Decree of 21

February 2005. Besides the Royal Decree, several other laws regulate aspects of GMOs in a

wider context. For example the Flemish regulation concerning environmental permits refers to

GMOs in Title I (Vlarem I) and Title II (Vlarem II). Specifically, but not exclusively, the articles

51.1 of Vlarem I, 5.51.2.2 and 7.1.1.6 both of Vlarem II are relevant. The same goes for the

annexes 5.51.3 and 5.5.1.4 of Vlarem II.

A relevant court case concerns the request to permit a field trial to grow GM poplars. This

request was refused by the Ministries of Environment and Public Health, but then the Council of

State (Raad van State) suspended the decision on the basis of a breach of law.

The Netherlands

The Dutch rules on GMOs also find their basis in the international regulations, especially the

European rules. The decree ruling GMOs is the Decree of 25 January 1990 regulating

environmental noxious substances.31 Using GMOs requires a formal permit provided by the

Ministry of Social housing, Spatial planning and Environment.

Commercial GMO production has not yet taken place in the Netherlands.32

Romania

No English version of local Romanian rules on GMOs was found. Romania already in 1998

introduced 14 varieties of genetically modified soy.33 When Romania became an EU Member

State they officially declared the whole country as a GMO Free Zone. In practice one can be

fairly sure that GMOs never disappeared in the region. Nowadays the agriculture minister of the

country firmly supports the use of GMOs, mainly to counter increasing food prices.34

Sweden

29

DUNMORE C., “EU Lawmakers vote to widen proposed GM crop bans ”, Reuters, 12 April 2011,

http://uk.reuters.com/article/2011/04/12/us-eu-gmo-cult ivation-idUKTRE73B4DL20110412 (accessed on 13 April

2011). 30

Directive 2001/18/EC of 12 March 2001 on the deliberate release into the environment of genetically modified

organisms and repealing Council Directive 90/220/EEC, O.J. 17 April 2001, L 106/1. 31

Besluit van 15 januari 1990 tot vaststelling van een algemene maatregel van bestuur krachtens artikel 24 van de

wet Milieugevaarlijke stoffen, www.cogem.net/page.ocl?pageid=24&version=&mode= (accessed on 24 April 2011). 32

GMO Compass, Field trials and commercial cultivation in the Netherlands, www.gmo-

compass.org/eng/news/country_reports/ (accessed on 24 April 2011). 33

INFOMG, GMOs in Romania, www.infomg.ro/web/en/GMOs_in_Romania (accessed 24 April 2011). 34

www.euranet.eu/eng/programme/English-Programmes/Romania -GM-food-for-thought.

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The use of GMOs in Sweden is regulated in the Environmental Code. Chapter 134 states that a

permit or notification is necessary before undertaking any activities involving GMOs. A risk

assessment of the activity considered is obligatory and appropriate protective measures need to be

taken. Thereby the activity should be ethically justifiable.35

The rules in the Environmental Code are supplemented by some ordinances and regulations. For

example: The Genetically Modified Organisms (Deliberate Release) Ordinance (SFS 2002:1086)

and the Genetically Modified Organisms (Contained Use) Ordinance (SFS 2000:271) set out

more detailed rules on when consents or notifications are required for genetic engineering

activities.36

3. Soil management

3.1 The importance of an international and national regulation

3.1.1 An international challenge

Although no political agreement on the legislative proposal was reached up to now, it is

worthwhile to mention the initiative on proposing a Soil Framework Directive.37

The framework directive on soil would include measures for the restoration and remediation of

degraded soils to a level of functionality consistent at least with the current and approved future

use.38 The idea is to approach the protection of soil on a holistic basis. Member States would have

to identify, describe and assess the impacts of their policies in particular on spatial planning,

transport, energy, agriculture, rural development, forestry, raw material extraction, trade and

industry, product policy, tourism, climate change, environment, nature and landscape.39 Such a

Soil Framework Directive would be an improvement over the actual situation. In 2006 only nine

Member States had specific legislation on soil protection, the others relied on elements found in

other policies.40 Karl Falkenberg, Director-general of Environment, claims that the demand for a

soil regulation is growing and soil regulation will be one of the strategic points to focus on during

35

MINISTRY OF ENVIRONMENT, The Swedish Environmental Code, A résumé of the text of the Code and

related Ordinances, Genetic Engineering , Danagrards Grafiska, Stockholm, Sweden, p 30. 36

www.gmo.nu/gmoenglish/topmenu/rulesandresponsibilities.4.778a5d1001f29869a7fff1249.html (accessed 24

April 2011). 37

http://ec.europa.eu/environment/soil/process_en.htm. 38

Ibid., Article 1 and 13. 39

Ibid., Article 3. 40

EUROPEAN COMMISSION, Proposal for a Directive of the European Parliament and of the Council

establishing a framework for the protection of soil and amending Directive 2004/35/EC , Brussels, 22 September

2006, Com(2006) 232 final, p. 7, ec.europa.eu/environment/soil/pdf/com_2006_0232_en.pdf, last visited 6 June

2010.

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the next year.41 Until such a soil regulation will be implemented, we have to refer to several

separate regulations linked to soil management. An overview of the most important international

rules is listed in the table below.

Table II: relevant regulation regarding soil

Convention for the Protection of the Alps (Alpine Convention), 1991

Regulation (EC) No 1907/2006 of the European Parliament and of the Council of 18 December

2006 concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals

(REACH)

Council Directive 80/68/EEC of 17 December 1979 on the protection of groundwater against

pollution caused by certain dangerous substances

Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in

particular of the soil, when sewage sludge is used in agriculture

Directive 2000/60/EC of the European Parliament and of the Council of 23 October 2000

establishing a framework for Community action in the field of water policy (Water Framework

Directive – WFD),

Proposal for a Directive of the European Parliament and of the Council establishing a framework

for the protection of soil and amending Directive 2004/35/EC

Directive 2006/116/EC of the European Parliament and of the Council of 12 December 2006 on

the protection of groundwater against pollution and deterioration


establishing a framework for Community action to achieve the sustainable use of pesticides

Another element to consider is the legal regulation of spatial planning. Nearly all of these rules

are national. Once permission is received from the owner of the site, aspects linked to

infrastructure, destination of the area should be taken up locally, eventually together with

requesting an exploitation permit.

The necessary approvals will differ between phytoextraction and phytostabilization. In the

following paragraph the aspects of both techniques are further elaborated.


Soil as such is mainly regulated by local rules of the Member States. However, soil becomes

more and more a point of attention on the European level. A lot is related to the important and

multiple functions soil has in biodiversity, environmental health and human well being. Several

European policies (like water, chemicals, waste, agriculture) have a direct or indirect impact on

soil management and protection. But these are not sufficient for an adequate sustainable

management of the soil. For these reasons the European Commission adopted a “Soil strategy”

41

Speech of Karl Falkenberg, Pricing the Earth, the European Green Week in Brussels, June 2010.

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and a proposal for a framework directive on soil in 2006. Despite these efforts no approval could

be obtained up to now.42

Other aspects in this chapter on soil management are regulated on the European level with impact

on local rules in the Member States: sludge, manure, (ground)water, herbicides. Thereby one

should bear in mind that the European legislation on nitrates (fertilizers) is under review. Since

the actual European directive is at the basis of most regulations in Member States, this will have

an impact on local rules. Relevant regulations in Member States are further elaborated in the

paragraph relevant to the topic.

Belgium

In Belgium soil management falls under the authority of the regions. The Flemish region has an

extensive legislation on soil remediation. Both obligatory and voluntary remediation of polluted

soils is possible.43

The Netherlands

The Dutch Soil Protection Act of 1987 is the basis for legal soil protection in the Netherlands. It

includes the concept of historical pollution (before 1 January 1987), before which no general

obligation for sanitation exists. Furthermore background and intervention levels concerning soil

contamination have been set. And the focus is on sustainable soil management whereby soil and

water are in practice closely linked.

New initiatives are taken with the aim at speeding up remediation of contaminated soils by, for

example, reducing and simplifying rules. The decision “uniform remediation” is a rule applicable

to all similar remediations that need execution on short notice.44 The estimation is that 60 % of all

contaminated sites in the Netherlands will fall under this regulation. An optimization of the

decision “uniform remediation” is expected during 2011.

Romania

In Romania the Ministry of Agriculture, Forests and Rural Development is responsible for the

safety and protection of soil and forests.45

Under rule “GEO No. 195/2005”, pollution of the soil, atmosphere or water by evacuation of

waste or dangerous substances is considered a criminal offence whenever such pollution poses a

threat on human, vegetal or animal life.

As regards the historic contamination of soil and groundwater, GEO No. 195/2005 does not

expressly provide for the extent of the parties’ liability. If pollution occurs the actual owner shall

42

ec.europa.eu/environment/soil/process_en.htm. 43

Decree of 27 October 2006 on soil remediation and soil protection, Belgian State Gazette 22 January 2007. 44

wetten.overheid.nl. 45

http://www.iclg.co.uk/khadmin/Publicat ions/pdf/751.pdf.

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be held liable for damages. This is in line with the principle of “the polluter pays”. The actual

owner may then turn against the seller for the purpose of recovering the compensation amount.

Sweden

In Sweden soil falls under the same regulation as groundwater, a water area, etc. does. The main

criterion for the applicability of the Environmental Code is the presence of potential harm to

human health or the environment.46 In that case a supervisory authority may require the person or

persons responsible to remediate the damage. The date when the pollution took place is irrelevant

to the application of the provisions, although only contamination caused by environmentally

hazardous activities after June 30 1969 will incur liability under the Environmental Code.47

However one should bear in mind that the Swedish Environmental Code is further elaborated in

several ordinances made by the Government.48

3.2 Phytoremediation: the difference between stabilization and extraction

Since there is a difference in impact on the soil between stabilization and extraction, applicable

(elements of) regulations differ also. For a better understanding the relevant distinctions between

both techniques will be explained, followed by an overview of relevant regulations. The most

commonly used techniques for phytoremediation of contaminated soil are stabilization and

extraction. Both techniques use plants to achieve their objectives and differ mainly in the process

to achieve these objectives.

Stabilization focuses on immobilizing the contaminants in a way that they are unavailable for

uptake in the (harvestable parts of the) plants and leaching into the environment is prevented.

However, the contaminants remain in the soil.

Extraction aims at the uptake of the contaminants by harvestable parts of the crops. Subsequently

the contaminated biomass is harvested and removed from the site. The result is that the

contamination in the soil is reduced.

This difference between the two techniques has an impact on the applicability of regulations for

all subsequent phases of a phytoremediation project.

46

MINISTRY OF ENVIRONMENT, The Swedish Environmental Code, A résumé of the text of the Code and

related Ordinances, Genetic Engineering , Danagrards Grafiska, Stockholm, Sweden, p. 27. 47

Ibid., p. 27-28. 48

http://www.sweden.gov.se/sb/d/2023/a/22847 (accessed on 15 April 2011).

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3.2.1 Stabilization

Phytostabilization is an approach aiming at decreasing bioavailability. It can be used on sites that

are heavily contaminated with metals using a combination of plants and soil amendments.49 It is

through these amendments that the availability of the contaminants for uptake by plants is

reduced. Simultaneously the mobility in and leaching from the soil is stopped or at least

diminished.

A few remarks should be made. Amending substances to soil is de facto changing the

composition of that soil. Next to the positive effect of stabilizing contaminants, other side effects

are also possible and probable. However, an element to consider is that adding substances to the

soil can immobilize some substances and at the same time mobilize others.50 Contamination of

the groundwater by these mobilized contaminants is possible. Especially leaking into the

groundwater is a risk. Consequently one should consider and respect the legislation on

groundwater.

Other undesirable effects of amendments can be the change of the soil structure (for example

zeolites with high sodium content destroy the soil structure) or immobilization of essential

elements.51 This can result in the loss of biodiversity and/or habitats, triggering related

legislation.

Last but not least, when soil is chemically treated or changed, it becomes subject to the REACH

regulation. In case of phytostabilization this is clearly so. But since it is not the goal to excavate

the soil and put it on the market or use it in articles, the obligation remains rather theoretical.

Can we be sure that the amendments used are safe? Two commonly used amendments are

analysed in the following paragraphs.

Amendments

The amendments used for stabilizing contaminants are (for example) liming agents, phosphates

(H3PO4, triple calcium phosphate, hydroxyapatite, phosphate rock), trace element (Fe/Mn)

oxyhydroxides, organic materials (e.g., biosolids, sludge, or composts), natural and synthetic

zeolites, cyclonic and fly ashes, and steel shots.52

Orthophosphoric acid (H3PO4)

49

VANGRONSVELD J., HERZIG R., THEWYS T. e.a., Phytoremediation of contaminated soils and groundwater:

lessons from the field, Environ Sci Pollut Res 2009, Springer-Verlag, 16, p. 766. 50


lessons from the field, Environ Sci Pollut Res 2009, Springer-Verlag, 16, p. 767 and 770. 51

Ibid. p. 767. 52

Ibid. p. 766.

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Orthophosphoric acid (H3PO4) is a substance that is included in the REACH lists as toxic for

reproduction.53 By consequence this substances is subject to authorization and should be phased

out. Should this substance then be used as a soil amendment in the framework of

phytoremediation? Strictly speaking it is still possible, since the first step towards authorization is

putting a substance on the candidate list. Orthophosphoric acid is not yet amongst these 16

substances on the official candidate list.

Sewage sludge

Sludge is a soupy material containing significant quantities of water and solid particles.

Commonly sludge originates from the process of treatment of waste water. Due to this treatment,

sludge tends to concentrate heavy metals and poorly biodegradable trace organic compounds as

well as some potentially pathogenic organisms (like viruses, bacteria).54 But sludge also has

positive aspects. It contains substances usable for fertilizing soils and combating erosion.

In 1986 a directive55 was approved with the objective to eliminate or at least control the harmful

effects of sludge on agriculture soil, environment and humans and still encourages the use of

sewage sludge because it conserves organic matter and completes nutrient cycles. From that

moment on the use of untreated sludge in agriculture is forbidden, except when the sludge is

injected or incorporated in the soil. The limit values mentioned in the directive should always be

respected. On the basis of article 12 of the same directive Member States can set more stringent

limits. And they did so, as shown in the table below.

Limits for organic compounds in sludge (expressed per unit of dry sludge). From EU (2001)56

AOX

Mg/kg

DEHP

Mg/kg

LAS

Mg/kg

NP/NPE

Mg/kg

PAH

Mg/kg

PCB

Mg/kg

PCCDD/F

Mg Teq/kg

EU 500 100 2600 50 6 0.8 100

DENMARK 50 1300 10 3

SWEDEN 50 3 0.4

GERMANY 500 0.2 100

However, growing plants for phytoremediation and as feedstock for biofuel is not an agricultural

activity according to the definition of agriculture in the directive.57 Thus, one could conclude that

53

Appendix 5 substances toxic for reproduction: category 1, REACH. 54

ec.europa.eu/environment/waste/sludge/index.htm, last visited on 6 June 2010. 55

Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil,

when sewage sludge is used in agriculture, O.J. 4 July 1986, L 181, eur-

lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31986L0278:EN:HTML, last visited on 6 June 2010. 56

BIOPROS, Solutions for the safe application of wastewater and sludge for high efficient biomass production in

Short-Rotation-Plantations, D5 – Guidelines on safety issues for SRP wastewater application , 14 February 2005,

Sweden, February 2006, p 11,

http://www.biopros.info/uploads/media/BIOPROS-D05.pdf, last visited on 9 June 2010. 57

Agriculture means the growing of all types of commercial food crops, including for stock rearing purposes.

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untreated sewage sludge can be used as an amendment on site for phytoremediation. But, it is

advisable to follow the more strict rules and limits in an environmentally friendly remediation

project.

In 1991 the Urban Waste Water Treatment Directive58 added a few aspects to the use of sludge

from urban waste water treatment. In the directive sludge is defined slightly different as residual

sludge, whether treated or untreated, from urban waste water treatment plants (article 2, 10). The

directive explicitly encourages the re-use of sludge whenever appropriate. In practice sewage

sludge has been employed on agricultural land, for forestry and in land reclamation operations,

such as for disused mines or closed landfills.59

3.2.2 Extraction

Extraction is the use of plant mechanisms to remove contaminants from the soil into harvestable

parts of the crops. These plants are regularly removed from the site resulting in a decrease of soil

contamination.

Bioavailability

For phytoextraction to succeed, contaminants must be bioavailable. The degree of availability for

uptake by plants varies according to the contaminant concerned and the capability of the used

crop.

Many metal contaminants are essential micronutrients for the plant. In common nonaccumulator

plants, accumulation of these micronutrients does not exceed their metabolic needs.60 However

some plants can accumulate more than what they need. Hypoaccumulators do not only

accumulate substances they need, but also absorb high amounts of contaminants. These

contaminants accumulate in the foliage, resulting in a contaminated feedstock. This is important

for the further processing of the harvest and the eventual waste part of the crop.

Amendments and fertilization

Contrary to stabilization, for extraction amendments are used to increase the bioavailability of

contaminants. This increased mobility of contaminants can lead to leaching of hazardous

elements into the groundwater.

58

Directive 91/271/EEC of 21 May 1991 concerning urban waste-water treatment, O.J. 30 May 1991, L 135. 59

http://ec.europa.eu/environment/waste/sludge/pdf/part_i_report.pdf 60

LASAT M., Phytoextraction of metals from contaminated soil: a review of plant/soil/metal interaction and

assessment of pertinent agronomic issues, Journal of Hazardous Substance Research, Volume 2, 2000, p 5-1,

citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.15.7236&rep=rep1&type=pdf, last visited on 6 June 2010.

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The new Groundwater directive61 includes legal requirements to prevent or limit input of

pollutants into the groundwater. The limit values are in line with those in the Water Framework

Directive (WFD).62 However, before 2012, year that the WFD will be fully operational63, the old

Groundwater directive 64 remains also in place. But, in the period between 16 January 2009 and

22 December 201365, any new authorisation procedure pursuant to substances prohibited66 or

limited67 shall take into account the requirements set out in the new Groundwater directive68.

Increasing the uptake of lead (Pb) by crops, ethylene-diamine-tetraacetic acid (EDTA) is

commonly added to the soil in phytoremediation projects. The substance is however regarded as

persistent organic pollutant and its poor biodegradability leads to accumulation in the

environment69. It has been found to be both cytotoxic and weakly genotoxic in laboratory

animals. Oral exposures have been noted to cause reproductive and developmental effects in

animals.70 At this moment I could not find any reference to this substance in REACH and it

seems that the substance is free to use. But in line with the European water regulations, EDTA

could be claimed to fall under Annex VIII point 5 of the WFD and therefore the input into

groundwater should be prevented or at least limited.71

Growing crops for biofuel in an economically viable way supposes to harvest as much as possible

or at least enough biomass. The intensive cultivation character requires a frequent nutrient input

for highest production. Heavy fertilization of the soil is necessary and by using waste

water/sludge the cost for nitrates and phosphates decreases substantially.72

61

Directive 2006/118/EC of the European Parliament and of the Council of 12 December 2006 on the protection of

groundwater against pollution and deterioration, O.J. 27 December 2006, L 372. 62

EUROPEAN COMMISSION, Groundwater protection in Europe, European Communities 2008, p. 27,

http://ec.europa.eu/environment/water/water-framework/groundwater/brochure/en.pdf, last visited 7 June 2010. 63

Article 11, 7 of Directive 2000/60/EC of the European Parliament and of the Council of 23 October 2000

establishing a framework for Community action in the field of water policy (WFD), O.J. 22 December 2000, L 327. 64

Council Directive 80/68/EEC of 17 December 1979 on the protection of groundwater against pollution caused by

certain dangerous substances, O.J. 26 January 1980, L 20, http://eur-

lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31980L0068:EN:HTML. 65

Article 7 of the Groundwater Directive. 66

Article 4 of Directive 80/68/EEC. 67

Article 5 of Directive 80/68/EEC. 68

Articles 3, 4, and 5 of the Ground Water Directive. 69

YUAN Z. and VANBRIESEN J., Environmental Engineering Science. May/June 2006, 23(3): p 533,

www.liebertonline.com/doi/abs/10.1089/ees.2006.23.533, last visited on 8 June 2010. 70

FINAL REPORT on the Safety Assessment of EDTA, Calcium Disodium EDTA, Diammonium EDTA,

Dipotassium EDTA, Disodium EDTA, TEA-EDTA, Tetrasodium EDTA, Tripotassium EDTA, Trisodium EDTA,

HEDTA, and Trisodium HEDTA, International Journal of Toxicology, 2002, Vol. 21, No. 2 Suppl, 95-142,

ijt.sagepub.com/cgi/content/abstract/21/2_suppl/95, last visited on 6 June 2010. 71

Article 6, 1 of Directive 2006/116/EC of the European Parliament and of the Council of 12 December 2006 on the

protection of groundwater against pollution and deterioration (Groundwater Directive), O.J. 27 December 2006, L

372. 72


Short-Rotation-Plantations, D4 – Report on ongoing research and gaps in SRP knowledge , 14 February 2005,

Sweden, February 2006, p 7, http://www.biopros.info/uploads/media/BIOPROS-D05.pdf, last visited 8 June 2010.

http://en.wikipedia.org/wiki/Cytotoxicity

http://en.wikipedia.org/wiki/Genotoxicity

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The need for fertilizers in these projects is frequently seen as one of the solutions to the surplus of

manure that exists in most European countries. But, what to do with the regulations on nitrates?

Despite the ambiguity surrounding the question if phytoremediation is an agricultural activity

(the crops are not grown for food or feed) and the actors in such projects being farmers, we would

advise to follow the regulations on the use of nitrates as written in the Nitrates Directive73,

especially those stipulated in Annex II and III of the Directive. Both Annexes contain, for

example, measures limiting the time when fertilizers can be applied on land and criteria

describing soil conditions limiting the application of fertilizer. A maximum limit to the fertilizers

is foreseen in the Directive. However, Member States can deviate from this limit on condition

they do not jeopardize the objectives of the Directive.

Note that application of fertilization is defined as “the addition of materials to land whether by

spreading on the surface of the land, injection into the land, placing below the surface of the land

or mixing with the surface layers of the land”.74

Plant protection

Another major crop maintenance practice is weed control. It seems that most (short-rotation)

plantations for biomass face problems due to the presence of weeds that hinder the growth of the

planted material, especially during the first year. As a consequence, the biomass production is

heavily reduced during the next years.75

A situation absolutely needing weed control, is the problem with Broomrape (Orobanche ramosa

linnaeus). Broomrape is a very invasive, parasite plant that grows on a wide range of crops,

oilseeds and vegetables.76 Problems with this plant destroying up to 70 % of the sunflowers

occurred in Europe.77

Herbicides come under the general category of pesticides. Pesticides sold within EU must be

approved by the regulatory bodies and in general are regulated under the Plant Protection

Directive. Pesticides are substances and products intended to influence fundamental processes in

73

Council Directive of 12 December 1991 concerning the protection of waters against pollution caused by nitrates

from agricultural sources (Nitrates Directive), O.J. 31 December 1991, L 375, consolidated version of 20 November

2003 available on eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CONSLEG:1991L0676:20031120:EN:PDF,

last visited on 8 June 2010. 74

Article 2, h of the Nitrates Directive. 75


Short-Rotation-Plantations, D5 – Guidelines on safety issues for SRP wastewater application , 14 February 2005,

Sweden, February 2006, p 17, http://www.biopros.info/uploads/media/BIOPROS-D05.pdf, last visited 9 June 2010. 76

Refer to

www.dpi.vic.gov.au/dpi/nreninf.nsf/LinkView/D3E4DB57D46E18D6CA256BCF000AD575663C5274163D2336C

A256E8D001EFC6C, last visited on 8 June 2010. 77

http://www3.interscience.wiley.com/journal/119212373/abstract?CRETRY=1&SRETRY=0, last visited 8 June

2010.

http://www.dpi.vic.gov.au/dpi/nreninf.nsf/LinkView/

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living organisms. They are used to kill or control harmful organisms such as weeds or insects.78

At the same time pesticides can have negative effects on human health and the environment,

which represent high costs for society. Therefore the directive on plant protection lays down strict

rules for the authorisation of products. The other aspect that is regulated are residue limits, but

these are only available on food- and feedstuffs.

Legislation on the use of pesticides is however lacking. In 2006 the Commission developed a

Thematic Strategy on the Sustainable Use of Pesticides to make up for this gap on rules for use.

Proposals for a Framework Directive on the use and one for a Regulation on the placing of plant

protection products on the market were included. In October 2009 the Framework Directive79 on

the use of pesticides was approved. Member States shall bring into force the laws, regulations and

administrative provisions necessary to comply with this Directive by 14 December 2011.

Evapotranspiration via the leaves

Volatile organic contaminants are by some plants preferentially released through

evapotranspiration via the leaves.80 Thereby they contaminate the ambient air. Since the projects

in Rejuvenate 2 do not deal with phytoremediation as a technique to clean such contaminated

sites, this topic is not further analyzed.


The Directive on sludge81 provides flexibility in national implementation resulting in a great

variety in approaches and limit values.82 For example the applicable rules will differ in relation to

the use of the sludge, and more specifically on the classification of the cultivation of crops for

phytoremediation and the production of bio-energy as an agricultural activity or not. This

classification differs per Member State. Whilst most national rules regulate sludge use in

agriculture in a separate framework, use outside of agriculture falls in general under waste law. In

view of the objective of the phytoremediation projects, it is advisable to respect at least the more

stringent rules when using sewage sludge.

78

In Community legislation, pesticides have usually been divided into two major groups (plant protection products

and biocides). Plant protection products (PPPs) contribute to high agricu ltural yields and help to ensure that good

quality food is available at reasonable prices. Biocides are e.g. important for public health protection and for

preservation of materials. 79

Directive 2009/128/EC of the European Parliament and of the Council of 21 October 2009 establishing a

framework for Community action to achieve the sustainable use of pesticides, O.J. 24 November 2009, L 309,

http://eur-lex.europa.eu/JOHtml.do?uri=OJ:L:2009:309:SOM:EN:HTML, last visited on 9 June 2010. 80


lessons from the field, Environ Sci Pollut Res 2009, Springer-Verlag, 16: p. 784. 81

Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when

sewage sludge is used in agriculture, O.J. 4 July 1986, L 181. 82

ECOLOGIC, Report on the Implementation of the Sewage Sludge Directive 86/278/EEC , IEEP, May 2009, p. 39,

ec.europa.eu/environment/waste/reporting/pdf/Sewage%20sludge_Direct ive.pdf (accessed 25 April 2011).

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Belgium, the Netherlands and Sweden have introduced limits for heavy metals in sewage sludge

that are more lower than those in Directive 86/278/EEC83 setting provisions beyond the

obligations of the Directive.84 Romania has set its limit values to those allowed by the

Directive.85

Fertilization of the soil might be necessary to succeed in growing enough biomass and achieve

good results in phytoremediation. The European rules on nitrates have been implemented

throughout Europe. High nutrient pressure exists in the Netherlands and Belgium (Flanders),

whilst the pressure is low in Eastern Europe, mainly because of the low input of fertilizers and

livestock density.86 All Member States are obliged to establish one or more action programmes

with measures concerning the period fertilization is prohibited, the limitation of land application

of fertilizers and land application near waters or on slopes.87

On the basis of the Framework Directive on the use of pesticides, Member States will have to

adopt National Action Plans that, amongst other tasks, encourage integrated pest management.

This means “careful consideration of all available plant protection methods and subsequent

integration of appropriate measures that discourage the development of populations of harmful

organisms and keep the use of plant protection products and other forms of intervention to levels

that are economically and ecologically justified and reduce or minimise risks to human health

and the environment”.88 Principles of integrated pest management are for example the use of

resistant/tolerant cultivars, the use of balanced fertilisation, liming and irrigation/drainage

practices.89 In concreto, Member States should take all necessary actions to promote low

pesticide-input pest management, giving wherever possible priority to non-chemical methods and

attending carefully to the quality of the aquatic environment. Thereby measures taken under other

regulation to protect sensitive groups and biodiversity should be respected. By 14 December

2011 all Member States should comply with this Directive through local laws, regulations and

administrative provisions.90

83

Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in particular of the soil, when

sewage sludge is used in agriculture, p. 6. 84

ECOLOGIC, p. 4. 85

ECOLOGIC, Executive summary, Report on the Implementation of the Sewage Sludge Directive 86/278/EEC ,

IEEP, May 2009, ec.europa.eu/environment/waste/reporting/pdf/Sewage%20sludge_Directive.pdf (accessed 25 April

2011). 86

EUROPEAN COMMISSION, Report from the Commission to the Council and the European Parliament on

implementation of Council Directive 91/676/EEC concerning the protection of waters against pollution caused by

nitrates from agricultural sources based on Member States reports for the period 2004 -2007, Brussels, 9 February

2010, COM (2010)47 final, p. 4, eur-lex.europa.eu/lexUniServ/LexUniServ. 87

Ibid., p 8. 88

Article 3, 6 of Directive 2009/128/EC. 89

DIRECTIVE 2009/128/EC, Annex III – General principles of integrated pest management. 90

Article 23 of Directive 2009/128/EC.

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II. GROWING AND HARVESTING THE CROPS

1. Introduction

Part II describes the international legal aspects of growing crops on contaminated soil and

harvesting these crops. Similar to the previous chapter, the focus is on the European legislation as

the basis for national rules (Directives) or as directly enforceable (Regulations). Strategic

communications of the Commission and proposals for new legislation are considered only when

it is probable that these will become formal obligations in the near future.

In Rejuvenate 1 a preliminary analysis of legal aspects was performed. Five regulatory domains

were studied: contaminated land, waste management, water resources, agriculture, and biomass

conversion, mainly in national legislation. However, this second chapter, like the first one,

follows the structure of the DST and thereby covers several legal domains as relevant. This

methodology is based on our previous experiences that following the process of the project gives

the most practical and complete overview of the legal elements. The latter is at risk when

focusing on a limited selection of legal domains.

For reasons of transparency and efficiency the hierarchy of legislation is respected in the study.

First the European legislation is analysed, followed by legislation of the Member States and then,

if relevant, regional91 legislation.

Inserted table I gives an overview of the European rules that are retained and discussed as

relevant for growing and harvesting:

Table I: relevant regulation for growing and harvesting

Directive 67/548/EEC of 27 June 1967 on the approximation of laws, regulations and

administrative provisions relating to the classification, packaging and labelling of dangerous

substances

Regulation 2092/91 of 24 June 1991 on organic production of agricultural products and

indications referring thereto on agricultural products and foodstuff

Directive 91/676/EEC of 12 December 1991 concerning the protection of waters against

pollution caused by nitrates from agricultural sources

Regulation (EC) No 1907/2006 of 18 December 2006 concerning the Registration, Evaluation,

Authorisation and Restriction of Chemicals (REACH), establishing a European Chemicals

Agency, amending Directive 1999/45/EC and repealing Council Regulation (EEC) No 793/93

91

Regional is for this report defined as parts of Member States with considerable authority.

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and Commission Regulation (EC) No 1488/94 as well as Council Directive 76/769/EEC and

Commission Directives 91/155/EEC, 93/67/EEC, 93/105/EC and 2000/21/EC

Directive 2008/98/EC of 19 November 2008 on waste and repealing certain Directives

Regulation (EC) No 1272/2008 of 16 December 2008 on classification, labelling and packaging

of substances and mixtures, amending and repealing Directives 67/548/EEC and 1999/45/EC,

and amending Regulation (EC) No 1907/2006

Regulation (EC) No 1107/2009 of 21 October 2009 concerning the placing of plant protection

products on the market and repealing Council Directives 79/117/EEC and 91/414/EEC

Directive 2009/128/EC of 21 October 2009 establishing a framework for Community action to

achieve the sustainable use of pesticides

Regulation (EC) No 66/2010 of 25 November 2009 on the EU Ecolabel

2. Growing the crops

The legal analysis of the use of biomass grown on contaminated soil takes into account the

principles of sustainability, minimal (negative) environmental impact and an optimal closed

lifecycle concerning the use of the biomass. This is an important choice in case alternatives are

available and/or interpretation of rules is necessary. Because of the lack of specific reference to

contaminated biomass, there are situations where a legislation could be applicable per analogy,

meaning based on the intention and goal of that legislation. An example is the question if

legislation on agriculture is applicable on contaminated biomass or not. This element is further

explored in paragraph 2.1.

When growing the crops, one of the important objectives in this phytoremediation project is to

produce enough biomass for conversion into biofuel. Thereby it is likely that some fertilizing of

the soil and some plant protection actions will be necessary. In the paragraphs 2.2 and 2.3 we

respectively discuss the legal implications of fertilizing and look at the rules concerning plant

protection.

2.1 The crops are planted

Is planting crops for phytoremediation an agricultural activity? Previously agriculture was

officially the activity aiming at producing food or feedstock for animals for food. Nowadays

Europe’s agricultural policy encourages farmers to not only produce high quality food products,

but to seek also new development opportunities, such as “renewable environmentally friendly

energy sources”.92

92

EUROPEAN COMMISSION, DG Agriculture and rural development, The Common Agricultural Policy

explained, May 2009, 11 p., http://ec.europa.eu/agriculture/capexplained/index_en.htm.

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One can conclude on the basis of the European policy that it is logical to apply the principles of

good agricultural practice and the agricultural legislation on contaminated biomass. We will thus

approach the other aspects of growing crops taking into account that phytoremediation is an

agricultural activity.

Member States have their own interpretation on what is regarded as agriculture and what not,

definitions differ a lot.93 To understand the domain of agriculture one will need to analyze local

regulation and its relevance for growing crops on contaminated land that is not or was not used

for agriculture.

Often definitions of agriculture are broad. For example Sweden defines it as “including forestry,

hunting and fishing”, as well as “cultivation of crops and livestock production”.94 It then remains

to be investigated if specific legislation is applicable on the cultivation as discussed in this

project. On the other hand, one could consider to chose the most environmental options,

regardless of the fact that the activity is considered agriculture or not. After all, the objective is to

improve the quality of the environment and by consequence not reduce it by inappropriate

remediation of soils.

2.2 Fertilizing

2.2.1 General

Fertilizers are substances that are used on land to enhance growth of vegetation. Examples of

fertilizers are livestock manure, sewage sludge, chemical fertilizers, composts and residues from

fish farms. Fertilizers contain a nitrogen compound and thus excessive use of fertilizers

constitutes an environmental risk. Especially the eutrophication of water is a problem. It causes

excessive growth of algae and plants thereby disturbing the quality of the water and the balance

of organisms in that water.

The Nitrate Directive95 aims at reducing and preventing the pollution of water by nitrates.

Member States are obliged to establish code(s) of good agricultural practice.96 These codes

should cover, e.g., the periods when fertilizing is inappropriate; the rules for applying fertilizer

93

KARLSSON J., PFUNDERER S., SALVIONI C., Agricultural and Rural Household Income Statistics, Paper

prepared for presentation at the 94th

E.A.A.E Seminar, Ashford, United Kingdom, 9-10 April 2005,

ageconsearch.umn.edu/bitstream/24427/1/sp05ka01.pdf (accessed on 26 April 2011). 94

Indexmundi, Sweden, definition of agriculture, www.indexmundi.com/facts/Sweden/agriculture (accessed on 26

April 2011). 95

Directive 91/676/EEC of 12 December 1991 concerning the protection of waters against pollution caused by

nitrates from agricultural sources, O.J. 31 December 1991, L 375 (consolidated version: O.J. 20 November 2003, L

676). 96

Directive 91/676/EEC, article 4.

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near water courses or on steeply sloping, water-saturated, flooded, frozen or snow-covered

grounds. Member States may also include guidelines on crop rotation and on minimum quantity

of vegetation cover during certain (winter, rainy) periods.97 In concreto fertilization should be

limited to certain periods in the year, taking into account the situation, the condition and the

structure of the ground. The nutrient losses to water should in any case be limited to an

acceptable level. Therefore it is important to remember that when working with non-perennial

plants a minimum vegetation cover should be maintained during the non-grow season. In any

case it should be checked if the phytoremediation site is situated in a vulnerable zone, since for

these zones designated by the Member States on its territory, the rules are more stringent.98

All of above mentioned information should be available on national level on the basis of the

obligations set by the Nitrate Directive. Indeed, Member States should have implemented laws,

regulations and administrative provisions to comply with this directive before 19 December

1993.99

2.2.2 The use of specific fertilizers

Two specific fertilizers need more explanation because of their special characteristics: sewage

sludge (used an sich, not as input for composting) and compost.

Sewage Sludge

Sludge originates from the process of cleaning, mainly urban, waste water. The use of sewage

sludge was described in part I of the report “Legal aspects of crops selection for

phytoremediation purposes and the production of biofuel”.100

Compost

Compost is best defined as “the solid particulate material that is the result of composting, which

has been sanitized and stabilized”. The process of compositing is described as the “controlled

decomposition of biodegradable materials under managed conditions, which are predominantly

aerobic and which allow the development of temperatures suitable for thermophilic bacteria as a

result of biologically produced heat.101

There are positive aspects to using compost as a fertilizer. It generally improves the structure of

the soil and its biological and chemical properties. The impact of compost on the soil depends on

its composition. On turn the composition depends on the input material in the composting

process. Several types of waste may be composted, for example biodegradable waste, commercial

97

Ibid., Annex II. 98

Ibid., Annex III. 99

Ibid., Article 12. 100

See Chapter Soil management, paragraph Amendments, p 10. 101

INSTITUTE FOR PROSPECTIVE TECHNOLOGICAL STUDIES, End of waste criteria, final report, European

Commission, Joint Research Centre, 2008, p. 48, available on

susproc.jrc.ec.europa.eu/activities/waste/documents/Endofwastecriteriafinal.pdf (accessed on 22 August 2010).

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food wastes, forestry residues, waste from agriculture (including manure), waste from food and

beverage industries and sewage sludge.

In general compost is low in nitrogen available to plants. The nitrogen present in the organic

matter is only slowly released. On the other hand the amount of phosphate and potassium can

generally cover the need for these substances. Compost also supplies calcium, magnesium and

sulphur and other micronutrients.102 Consequently it can be used as a (partial) replacement for

other fertilizers. An advantage over chemical fertilizers is that compost brings organic matter to

the soil improving the soil’s structure.

Unfortunately, compost also has some negative aspects. The two elements that particularly

interest us, because of our objective to remediate contaminated soil, are the presence of heavy

metals and persistent organic pollutants. These contaminants are negative for soils and land in

normal condition, but especially so in conditions where the presence of heavy metals and

persistent organic pollutants is already elevated. On top, at this moment no specific European

legalisation exists regulating the quality and use of compost. However some guidelines can be

found in other regulations. For example, the End-of-Waste criteria of the new Framework

Directive on Waste, the Ecolabel Regulation and – to a minor extend – the Regulation on Organic

Agriculture.

End-of-Waste criteria (EoW)

In the strategy on the prevention and recycling of waste, the European Commission aims to

encourage recycling by clearly defining end-of-waste (EoW) criteria. Fulfilling the EoW criteria

would determine the moment when waste ceases to be waste and becomes a product. To

elaborate the methodology on EoW criteria and to set some examples, the Joint Research Centre

and the Institute for Prospective Technological Studies performed a study. One of the topics was

compost.103 The (potential) presence of contamination in compost was researched, especially the

presence of heavy metals. The findings showed that exceeding the actual contamination limits for

zinc, lead, cadmium and phosphate would not lead to critical effects.104 To have a negative

impact extremely high amounts or repeated inputs of these heavy metals to the soil should

continue over several years. The study concludes that it is best is to control contamination of

compost by quality checks on the nature and origin of the input material. The limits that are

proposed105 are in some cases lower than the actual country limits, but overall higher than the

limits one should respect to obtain an Ecolabel.

102

Ibid., 54. 103

Ibid., 47-154. 104

Ibid., 139. 105

In values g/kg (dry weight): cadmium = 1,5 – lead = 120 – zinc = 400.

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The resulting EoW criteria would support the production of quality compost, since they are to be

respected if one wants to market the compost as non-waste. At this moment most European

countries have some regulations governing directly or indirectly the production and/or use of

compost. In general these local regulations will need adaptation to the EoW criteria concerning

limit values and quality assurance, including harmonized technical standards on product

parameters, sampling and analysis.106

The Ecolabel

Secondly, there is influence of the Ecolabel107 for soil improvers and growing media. The

Ecolabel is the official environmental label of Europe. The explicit aim of the label is to promote

“the use of renewable materials and/or recycling of organic matter derived from the collection

and/or processing of waste material and therefore contributing to a minimization of solid waste

at the final disposal.”108 Companies whose products comply with the relevant product definition

and the related criteria can voluntarily apply for the European Ecolabel.

The criteria for the Ecolabel concerning soil include amongst other things limits for heavy metal

contaminants and organic pollutants in compost.109 The limits relate to the end product and not to

the input material. It appears that the limits imposed are more severe than necessary for the

environment and, on top, nearly impossible to achieve by producers.110 The findings reported in

the End-of-Waste report show that exceeding the contaminants limits (mentioned in the Ecolabel

criteria) for Zn, Pb and Cd and phosphate would not create critical impacts unless extremely high

amounts or repeated input over several years would happen. Therefore, the End-of-Waste report

proposes higher limits than the Ecolabel, but lower than those judged safe in the relatively high

French standard.111 Since most Member States have national limits lower than those used in

France, increasing the limits up to that level would reduce the actual quality targets for compost

and is therefore not appropriate. On the other hand, higher limits than in the Ecolabel regulation

(see figure 1) would stimulate the production, marketability and use of compost, with possibly an

increased use of the Ecolabel. By choosing a balanced solution the environment can maximally

benefit from the re-use of organic waste.

Figure 1: Limitation of hazardous substances as imposed by the Eco-label 112

106

Ibid., 100. 107

Regulation (EC) No 66/2010 of 25 November 2009 on the EU Ecolabel, O.J. 30 January 2010, L27. 108

INSTITUTE FOR PROSPECTIVE TECHNOLOGICAL STUDIES, o.c., p 138. 109

SMK, The European Eco-label user manual for Soil Improvers, The Netherlands, May 2006, 29 p.,

http://ec.europa.eu/environment/ecolabel/ecolabelled_products/categories/pdf/si_criteria2.pdf. 110

INSTITUTE FOR PROSPECTIVE TECHNOLOGICAL STUDIES, o.c., p. 140. 111

The ORBIT/ECN study111

stipulates that even with the French standard111

a continued use of compost would not

lead to critical soil values exceeding the stricter German standard period in less than 50 years., INSTITUTE FOR

PROSPECTIVE TECHNOLOGICAL STUDIES, o.c., p 140. 112

SMK, The European Eco-label user manual for Soil Improvers, The Netherlands, May 2006, p. 18,

http://ec.europa.eu/environment/ecolabel/ecolabelled_products/categories/p df/si_criteria2.pdf. (accessed on 21

August 2010).

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Organic agriculture

Another rule that could influence the use of compost is the concept of organic agriculture as laid

down in Regulation 2092/91.113 This Regulation contains limits on contaminants that should be

respected by farmers adhering to organic agriculture. However, these limits cannot be used but as

an indication of contamination limits for environmentally safe agriculture. The system of organic

agriculture cannot be recognized as such when applied to a contaminated site.114 The Regulation

is thus not discussed any further in view of its limited relevance for the phytoremediation project.

Local regulations

High nutrient pressure exists in the Netherlands and Belgium (Flanders), whilst the pressure is

low in Eastern Europe, mainly because of the low input of fertilizers and livestock density.115 All

Member States are obliged to establish one or more action programmes with measures

concerning the period fertilization is prohibited, the limitation of land application of fertilizers

and land application near waters or on slopes.116

In order to safeguard the free circulation of compost in the European internal market, standards

should be harmonized across the Member States. At this moment most Member States have

statutory standards for compost. Belgium has a quality system for compost managed by an

organisation VLACO vzw. This organisation performs regular audits and controls input material,

processes and product quality.117 The Netherlands also has a quality assurance system, but

participation is voluntary. Compost meeting the set of legal requirements obtains a certificate,

based on a positive assessment by an independent institute.118

The project was financed by the Swedish Association of Waste Management RVF and the

Swedish EPA. This system demands that input material should be of clean organic origin and

113

Regulation 2092/91 of 24 June 1991 on organic production of agricultural products and indications referring

thereto on agricultural products and foodstuff, O.J. 22 July 1991, L 198, consolidated version O.J. 1 January 2007, L

027.002. 114

See the rules of production in article 6 of the Regulation 2092/91. 115




2010, COM (2010)47 final, p. 4, eur-lex.europa.eu/lexUniServ/LexUniServ.

116

Ibid., p 8. 117

www.vlaco.be (accessed on 25 April 2011). 118

www.keurcompost.nl (accessed on 25 April 2011).

In the organic growing media constituents, the content of the following elements shall be lower than

the values shown below, measured in terms of milligrams per kilogram of dry weight (mg/kg-1 d.w.):

Zn 300 mg.kg-1

Cu 100 mg.kg-1

Ni 50 mg.kg-1

Cd 1 mg.kg-1

Pb 100 mg.kg-1

Hg 1 mg.kg-1

Cr 100 mg.kg-1

Limit values are applicable to organic constituents only. Maximum allowable concentrations specified

below (in mg kg-1 d.w.) are applied only to products containing material from industrial processes,

such as rice hulls, peanut hulls or sludges from the agro-food industry:

Mo 2 mg.kg-1

Se 1.5 mg.kg-1

As 10 mg.kg-1

F 200 mg.kg-1

Limit values are valid unless national legislation is more strict.

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source separated. The system is quite similar to the German version. The project goes on and at

the moment there are several anaerobic digestion plants and compost plants that have managed to

receive a certificate.

2.3 Plant protection

Previously plant protection119 regulation was mainly focussed on the marketing of these products.

Maximum residue limits existed for pesticides on food- and feedstuffs. In March 2009 a review

programme of existing pesticides was finalised. Both the marketing and the use of plant

protection products are regulated, respectively in a Regulation120 and a Directive121. The review

ensures that substances on the market are acceptable for the environment and human health. The

focus is no longer solely on food safety. A direct consequence is that the level of protection is

similar in all Member States. In the past protection varied widely and national rules could

continue to be applicable. This is no longer possible. Inherent to a regulation is the direct

applicability. Transposition into national legislation is not necessary.

Plant protection in the sense of the new Regulation includes protection against harmful

organisms, including weeds and improvement of plant production products. Commercial plant

protection products have to be authorised following the procedures in the regulation before they

can be put on the market or used.122 The authorisation shall define for what purposes which plant

product can be used.123 In case a certain use is not authorised, the authorisation holder, official or

scientific bodies involved in agricultural activities, professional agricultural organisations or

professional users may ask for an extension of the use. This extension can only be authorised if

the conditions mentioned in article 51 of the Regulation are respected.

Plant protection products need to be labelled in line with the requirements of Directive 1999/45

on the classification, packaging and labelling of dangerous preparations.124 An additional

regulation based on article 65 of the Regulation 1107/2009 will be adopted describing the

additional information and safety precautions that have to be taken. These phrases supplement the

119

The difference between Plant Protection products and biocides is that Plant Protection Products (PPPs) contribute

to high agricultural yields and help to ensure that good quality food is available at reasonable prices, whilst biocides

are important for public health protection and for preservation of materials. The latter products are not used in plant

protection and consequently the related regulation is not discussed in this article. 120

Regulation (EC) No 1107/2009 of 21 October 2009 concerning the placing of plant protection products on the

market and repealing Council Directives 79/117/EEC and 91/414/EEC, O.J. 24 November 2009, L 309. 121

Directive 2009/128/EC of 21 October 2009 establishing a framework for Community action to achieve the

sustainable use of pesticides, O.J. 24 November 2009, L 309/71. 122

Regulation 1107/2009, article 1 and 28. 123

Ibid., article 31. 124

This Directive will be fully replaced as of 1 June 2015 by Regulation (EC) No 1272/2008 of 16 December 2008

on classification, labelling and packaging of substances and mixtures, amending and repealing Directives

67/548/EEC and 1999/45/EC, and amending Regulation (EC) No 1907/2006, O.J. 31 December 2008, L 353.

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obligation of Directive 1999/45/EC. Without any doubt these are important data containing

valuable information for the users of these products.

For rules on the proper use of plant protection products the Regulation125 refers to the new

Directive 2009/128/EC on the use of pesticides.126 This Directive on the use of plant protection

products is an important step forward in the protection of human health and the environment from

pesticides. Indeed pesticides can have very negative effects that should be prevented or

controlled.

Member States have to adopt National Action Plans to reduce risk and impacts of pesticides,

promote integrated pest management and alternative approaches to reduce the use of pesticides.

The encouragement of integrated pest management is interesting. It means that, whenever

possible, priority should be given to non-chemical methods. However, the mistake made in the

past by importing foreign predators (Harmonia axyridis) for pest control should not be made

again. The impact on the local biodiversity is still very negative.

Furthermore, the Directive obliges Member States to provide training on the use of pesticides and

to inspect pesticide application equipment.

Last but not least, the Directive shall not prevent Member States from applying the precautionary

principle in restricting or prohibiting the use of pesticides in specific circumstances or areas.127 In

practice this means that one should still check the local legislation when planning to use plant

protection products. It could be forbidden in that particular country or for that particular use in

that country.

The Directive should be transposed in national legislation by 14 December 2011.128

Local regulations

As already mentioned, high nutrient pressure exists in the Netherlands and Belgium (Flanders),

whilst the pressure is low in Eastern Europe, mainly because of the low input of fertilizers and

livestock density.129 All Member States are obliged to establish one or more action programmes

125

Regulation 1107/2009, article 55. 126

Directive 2009/128/EC. 127

Ibid., article 2, 3. 128

Ibid., article 23. 129




2010, COM (2010)47 final, p. 4, eur-lex.europa.eu/lexUniServ/LexUniServ.

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with measures concerning the period fertilization is prohibited, the limitation of land application

of fertilizers and land application near waters or on slopes.130

3. Harvesting the crops

When harvesting the crops on the site, it is important to know how contaminated the crops are

and with what kind of chemical substances. This will have an impact on the classification of the

biomass as (potentially) hazardous or not. For further classification we also need to know if the

resulting biomass falls under waste rules or not. Indeed, obligations to store, transport and

manipulate are different for waste and non-waste.

At this moment no explicit rules on contaminated biomass exist. We need to look at several

regulations touching the characteristics and properties of the biomass to get a good view on the

legal aspects. Conclusions will be drawn by extrapolation of these rules.

The objective of Rejuvenate 2, as written down in the call for tenders and the approved Research

Project sets the framework for the study of both the status of the biomass and the classification as

hazardous. The “Use of contaminated land for biofuel crop production” is topic 3 of the

Rejuvenate 2 call.131 Biofuel crop production means the growing of plants to use these as

feedstock for an energy source. The approved Research Project Proposal132 refines the topic by

stipulating that usage of the crop production focuses in particular on secondary biofuels. Biofuel

is thereby to be understood as the fuel produced directly or indirectly from biomass, such as

fuelwood, charcoal, bioethanol, biodiesel, biogas and biohydrogen.133

Within this framework, the impact of the contamination of the plants and the classification of the

biomass as waste or non-waste is further analysed in following paragraphs.

3.1 The plants are contaminated

The whole idea behind phytoextraction is that plants grown on a contaminated site take up (part

of) the contaminants and consequently clean the soil of toxic substances. When the plants are

130

Ibid., p 8. 131

SNOWMAN, The Second Snowman Coordinated Research Call, Sustainable Soil Management, Applicants

Guide, SnowmanERAnet, 10 December 2008, p 18. 132

SNOWMAN, Crop Based Systems for Sustainable Risk Based Land Management for Economically Marginal

Degraded Areas, Phase II: Demonstration projects and evaluation decision support tool , Research Project Proposal,

Rejuvenate 2, p 9. 133

REJUVENATE, Crop Based Systems for Sustainable Risk Based Land Management for Economically Marginal

Degraded Areas, p. 19, available on www.snowman-era.net/content.php?horiz_link=12&vert_link=0, (last accessed

24 August, 2010).

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harvested part of the soil contamination is removed together with the biomass. This raises some

questions on the nature of the resulting harvested biomass. Referring to contamination with heavy

metals, these elements occur naturally in plants, but in lower quantities than when the crops grow

on contaminated soil. In phytoextraction plants are even selected on their potential uptake of

contaminants whilst able to survive and grow. Exact guidelines to decide which quantity of

contaminants in the harvested crops is such that the biomass should be considered toxic or

hazardous134, do not exist on European level. In principle the concentration of toxic substances in

the plants is higher than what it, in normal growing circumstances, would be, although lower than

in the soil. Differing considerably from their normal, natural composition, the plants/biomass

could be classified as ecotoxic. This conclusion is based on arguments found in the new Waste

Framework Directive and in the texts of REACH on hazardous substances. The Waste

Framework Directive would classify waste as ecotoxic when it “presents or may present

immediate or delayed risks for one or more sectors of the environment”.135 The contaminants in

the soil are considered to have a toxic, negative impact since this is exactly the reason for the

phytoremediation of the site. The same contaminants are now in the plants and thus these could

be seen as hazardous too. However, the concentration in the biomass could be significantly

different from the concentration in the soil. This could influence the classification of the biomass.

To assess the toxicological effect we need to consider two parameters: the amount of

contaminants in the biomass and the nature of the substances present in that biomass. The latter

should then be compared with the rules in the REACH-regulation. This is the case for non-waste

(see infra) as well as for waste, since the Waste Framework Directive states that the classification

as hazardous should be based on the European legislation on chemicals.136 Many of the

contaminants found in soils that need sanitation are in REACH listed as hazardous substances.

Hazardous substances are subject to authorization or restrictions.137 Cadmium is for example

classified as carcinogenic138 and some forms of lead are on the authorisation list, as is toluene. In

fact this confirms the conclusion above that contaminated biomass could be seen as dangerous

and ecotoxic.

134

It is important to note that the meaning of the term “contaminant” in the Rejuvenate I report is not similar to the

meaning of “hazardous substance” used in regulation and in particular chemical legislation. A contaminant is defined

in the report as a substance which is in, on or under the land and has the potential to cause harm (or to cause

pollution of controlled waters). (Rejuvenate I final report, p 35). A hazardous substance is classified as such on the

basis of certain characteristics, i.e. carcinogenic, mutagenic, toxic for reproduction, PBT or vPvBvT ((very)

persistent, (very) bioaccumulative and (very) toxic) (REACH, article 57, 67 and Annex XVII). 135

Directive 2008/98/EC of 19 November 2008 on waste and repealing certain Directives, O.J. 22 November 2008,

L 312/3, Annex VI, H14. 136

Ibid., Pre-ambule 14. 137

Regulation (EC) No 1907/2006 of 18 December 2006 concerning the Registration, Evaluation, Auth orisation and

Restriction of Chemicals (REACH), establishing a European Chemicals Agency, amending Directive 1999/45/EC

and repealing Council Regulation (EEC) No 793/93 and Commission Regulation (EC) No 1488/94 as well as

Council Directive 76/769/EEC and Commission Directives 91/155/EEC, 93/67/EEC, 93/105/EC and 2000/21/EC,

O.J. 25 May 2007, L 136/3, Title VII and Title VIII of REACH. 138

Ibid., Annex VII.

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Abstraction made of the conclusion if this contaminated biomass is waste or not, one could say

that it is reasonable and within the intention of European rules to classify the biomass as toxic for

the environment.139

3.2 Waste or not waste

Is harvested contaminated biomass waste? The new Waste Framework Directive defines waste as

“any substance or object which the holder discards or intends or is required to discard”.140 But

article 2 of the Waste Framework Directive excludes “… straw and other natural non-hazardous

agricultural or forestry material used in farming, forestry or for the production of energy from

such biomass through processes or methods which do not harm the environment or endanger

human health”.

A direct consequence of this formulation is that biomass needs to be natural and non-hazardous,

which is not the case for the contaminated biomass (See previous paragraph). The conclusion is

that this biomass is not excluded from the Waste Framework Directive and we will have to look

at the definition of waste for the classification.

The main purpose of growing crops on a contaminated site is to remediate that site. But the

intention is to use biomass for producing biofuel as a commercial valuable product that gives the

location some economic future. For the farmers it would add to their income and investors could

be interested in the use of the biomass. Indeed turning contaminated biomass into a financial

viable product would be an important motivator for private parties to invest in phytoremediation,

what on its turn would benefit the local population and the environment.

Could one argue that the harvested biomass is waste? An important number of cases brought for

the European Court of Justice (ECJ) show that there is no straightforward rule to decide if or

when something is waste. Several interpretations were put forward and in many cases the ECJ

had to make the final cut. The elements in the definition of waste141, are further elaborated with

other elements like re-use without further processing, economic value, market need, etc.

The new Framework Directive on Waste kept the definition of Directive 2006/12/EC, but without

the reference to the former Annex I. This Annex I contained a list of waste, but also included a

category covering all substances, materials, products not included in any other category of the

list. This last statement made Annex I de facto useless. Consequently, the definition in the new

directive is in practice similar to the former one, thus the lessons learned out of the court cases

are still valid.142

139

Directive 2008/98/EC, Annex III – H14. 140

Ibid., Article 3, 1. 141

Directive 2008/98/EC, article 3, 1. 142

Failing, up to now, any court decisions on the basis of the new Waste Directive 2008/98/EC.

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Comparing the harvesting of contaminated crops for the production of biofuel with the definition

of waste and the arguments used in court decisions, we can conclude that the biomass of a

phytoremediation site is not waste. Following arguments lead to this conclusion:

1. The economic feasibility of using the contaminated biomass for the production of biofuel

is an important criterion for the viability and success of the projects. Furthermore, the

Decision Support Tool considers in phase 3 financial aspects as an element for the

evaluation of proposed projects.

2. The suitability of the crops for the production of biofuel is taken into account in the

selection of the plants.

3. The crops are grown and treated (fertilizing, plant protection) with the clear aim to

produce biomass as feedstock for biofuel, whilst remediating the contamination.

4. Biofuel clearly is a commercial product. It has to be manufactured and this production is

not just a deactivation of harmful biomass, but real processing.

Above motivation is valid for the Rejuvenate 2 project and for possible future phytoremediation

projects. Rejuvenate 2 will analyse and assess the economic viability of phytoremediation by

really growing biomass on contaminated ground and producing biofuel. The aim is to prove that

phytoremediation is an economically valuable option for cleaning or upgrading contaminated

soil. The possibility to produce biofuel from the contaminated biomass would be an important

motivator for private projects and investments. It also would reduce the burden of the very long

time frame needed to clean land by phytoremediation.

Future private phytoremediation projects for the production of biofuel will be decided upon based

on their financial and economic viability. The biomass is grown with the goal to produce biofuel,

it is not re-used, not recycled, it is a first processing. Consequently, it is hard to defend that the

resulting biomass is to be classified as waste. Overall the grower and/or holder of the

contaminated biomass did not discard it, nor did he have the intention to discard. The goal is

rather to use it as an economic valuable and commercial product, namely feedstock for biofuel.

One reservation though: failing any specific regulation for phytoremediation projects on

contaminated soil, it could be that the European Commission is of the opinion that such

contaminated biomass should be regarded as waste. This way a legal structure with rules

protecting human health and environment becomes applicable. The question is if the European

Court of Justice would follow such classification.

Last but not least, the above does not exclude that after processing parts of the biomass could

become waste in the sense of the definition of waste in the Waste Framework Directive. This

aspect will be discussed in a next (to come) part on the processing of the biomass.

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Local rules

Belgium

In Belgium the waste legislation falls under the authority of the regions. In Flanders the actual

legislation is under review for adaption to the new European Framework Directive on waste.

Publication and implementation of the new decree is expected on the short term.

Netherlands

The Dutch Council of Ministries, upon recommendation of the Ministry of Social Housing,

Spatial Planning and Environmental management, accepted a change in the law of Environmental

Management.143 This change was necessary in order to implement on time the European

Framework Directive on waste in local rules. The goal of the directive and the local rules is

mainly to prevent waste as much as possible, to manage scarce materials and support sustainable

use. The new local rules have an option to no longer qualify certain processes as waste, i.e. on

condition that the materials concerned meet the end-of-waste criteria.

Romania

The Romanian policy governing waste management includes two main components: the National

Waste Management Strategy and the National Waste Management Plan.

Basic principles of environmental policy in Romania are set in accordance with European and

international provisions, ensuring protection and nature conservation, biological diversity and

sustainable use of its components.144

In order to comply with legislative requirements for waste management in Romania, integrated

waste management projects are developed under the National Waste Management Plan and the

Regional Waste Management Plans.145

Sweden

In Sweden waste is dealt with through the Environmental Code. The handling of waste, including

treatment facilities, landfills etc., is subject to the licensing regulations contained in that

Environmental Code that was approved in June 1998 and came into force on 1 January 1999.146

The definition of waste is based on the European definition of waste as stipulated in the new

Waste Framework Directive. Waste is every object, material or substance which the holder

disposes of, intends to dispose of or is obliged to dispose of. An annex to an ordinance of the

143

http://www.agentschapnl.nl/programmas-regelingen/websites-over-afval (accessed 27 April 2011). 144

UNITED NATIONS, National Reports, Romania, Waste Management, May 2010, p 1-10,

http://www.un.org/esa/dsd/dsd_aofw_ni/ni_pdfs/NationalReports/romania/waste.pdf (accessed 27 April 2011). 145

Ibid., p 5. 146

www.swegene.com/blog/legislation-of-waste-management-in-sweden.html.

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Environmental Code lists the categories of waste as also mentioned in the annex of the former

Waste Framework Directive.

Regulations about extended producer responsibility may be issued under the Environmental

Code. Extended producer responsibility means that the producer must ensure that the waste is

collected, transported away, recycled, reused or disposed of in such a manner as may be

necessary from the viewpoint of health and environmentally acceptable waste handling.

3.3 Should biomass be registered under REACH?

Annex V of the REACH Regulation contains exemptions from the obligation to register. For

example, substances occurring in nature are exempted, unless they meet the criteria for

classification as dangerous.147 Thus, one could argue that if biomass is sold to a processor, who

transfers the material into biofuel, that biomass is put on the market and the biomass should be

registered, because it contains hazardous substances. This situation has some similarities with the

“compost issue” that originally also had to be registered under the REACH Regulation, because

after composting it became a marketable product. For practical reasons and in line with the

intention of REACH, an exemption from registration for compost was included in Annex V of

the REACH Regulation.148 A similar exemption is defendable for contaminated biomass.

However up to now, such an exemption for contaminated biomass does not exist.

147

REACH, Annex V, entry 8 - Substances which occur in nature other than those listed under paragraph 7, if they

are not chemically modified, unless they meet the criteria for classification as dangerous according to Directive

67/548/EEC or unless they are persistent, bioaccumulative and toxic or very persistent and very bioaccumulative in

accordance with the criteria set out in Annex XIII or unless they were identified in accordance with Article 59(1) at

least two years previously as substances giving rise to an equivalent level of concern as set out in Art icle 57(f). 148

ECHA, Guidance for Annex V, Exemption from the obligation to register, March 2010, version 1,

http://guidance.echa.europa.eu/docs/guidance_document/annex_v_en.pdf (accessed on 25 August 2010), p 39. This

exemption covers compost when it is potentially subject to registration, i.e. when it is no longer waste according to

Directive 2008/98/CE, and is understood as being applicable to substances consisting of solid particulate material

that has been sanitised and stabilised through the action of micro-organisms and that result from the composting

treatment.

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III. BIBLIOGRAPHY

1. Legislation

Convention on the Conservation of European Wildlife and Natural Habitats (Bern

Convention), 1982, O.J. 10 February 1982, L 038.

Convention on Biodiversity (CBD), 1992, www.cbd.int, last visited 31 May 2010.

International Plant Protection Convention (IPPC), 1995, New Revised Text approved by the

FAO Conference, November 1997,

https://www.ippc.int/file_uploaded//publications/13742.New_Revised_Text_of_the_Internati

onal_Plant_Protectio.pdf, last visited 31 May 2010.

Convention for the Protection of the Alps (Alpine Convention), 1991, O.J. 12 March 1996, L

061.

Regulation (EC) No 1829/2003 of the European Parliament and of the Council of 22

September 2003 on genetically modified food and feed, O.J. 18 October 2003, L 268,

amended by Regulation (EC) No 1981/2006 of 22 December 2006, O.J. 23 December 2006,

L 368.

Regulation (EC) No 166/2006 of the European Parliament and of the Council of 18 January

2006 concerning the establishment of a European Pollutant Release and Transfer Register and

amending Council Directives 91/689/EEC and 96/61/EC, O.J. 4 February 2006, L 33.

Regulation (EC) No 1907/2006 of the European Parliament and of the Council of 18

December 2006 concerning the Registration, Evaluation, Authorisation and Restriction of

Chemicals (REACH), establishing a European Chemicals Agency, amending Directive

1999/45/EC and repealing Council Regulation (EEC) No 793/93 and Commission Regulation

(EC) No 1488/94 as well as Council Directive 76/769/EEC and Commission Directives

91/155/EEC, 93/67/EEC, 93/105/EC and 2000/21/EC, O.J. 30 December 2006, L 396.

Corrigendum to Regulation (EC) No 1907/2006 published in O.J. 29 May 2007, L 136.

Regulation (EC) No 1107/2009 of the European Parliament and of the Council of 21 October

2009 concerning the placing of plant protection products on the market and repealing Council

Directives 79/117/EEC and 91/414/EEC, O.J. 24 November 2009, L 309.

Council Directive 80/68/EEC of 17 December 1979 on the protection of groundwater against

pollution caused by certain dangerous substances, O.J. 26 January 1980, L 20.

Council Directive 86/278/EEC of 12 June 1986 on the protection of the environment, and in

particular of the soil, when sewage sludge is used in agriculture, O.J. 4 July 1986, L 181.

Council Directive 91/414/EEC of 15 July 1991 concerning the placing of plant protection

products on the market, O.J. 19 August 1991, L 230.

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Council Directive of 12 December 1991 concerning the protection of waters against pollution

caused by nitrates from agricultural sources, O.J. 31 December 1991, L 375.

Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of

wild fauna and flora (Habitat Directive), O.J. 22 July 1992, L 206.

Council Directive 96/62/EC of 27 September 1996 on ambient air quality assessment and

management; O.J., 21 November 1996, L 296.

Directive 98/8/EC of the European Parliament and of the Council of of 16 February 1998

concerning the placing of biocidal products on the market, O.J. 24 April 1998, L 123.

Council Directive 1999/31/EC of 26 April 1999 on the landfill of waste, O.J. 16 July 1999, L

182.

Council Directive 2000/29/EC of 8 May 2000 on protective measures against the

introduction into the Community of organisms harmful to plants or plant products and against

their spread within the Community, O.J. 10 July 2000, L 169.


establishing a framework for Community action in the field of water policy (Water

Framework Directive – WFD), O.J. 22 December 2000, L 327.

Directive 2001/18/EC of the European Parliament and of the Council of 12 March 2001 on

the deliberate release into the environment of genetically modified organisms and repealing

Council Directive 90/220/EEC, O.J. 17 April 2001, L 106.

Directive 2004/35/CE of the European Parliament and of the Council of 21 April 2004 on

environmental liability with regard to the prevention and remedying of environmental

damage, O. J. 30 April 2004, L 143.

Directive 2006/118/EC of the European Parliament and of the Council of 12 December 2006

on the protection of groundwater against pollution and deterioration, O.J. 27 December 2006,

L 372.

Directive 2009/28/EC of the European Parliament and of the Council of 23 April 2009 on the

promotion of the use of energy from renewable sources and amending and subsequently

repealing Directives 2001/77/EC and 2003/30/EC, O.J. 5 June 2009, L 140.


establishing a framework for Community action to achieve the sustainable use of pesticides,

O.J. 24 November 2009, L 309.

Commission Decision 2000/532/EC of 3 May 2000 replacing Decision 94/3/EC establishing a

list of wastes pursuant to Article 1 (a) of Council Directive 75/442/EEC on waste and Council

Decision 94/904/EC establishing a list of hazardous waste pursuant to Article 1 (4) of Council

Directive 91/689/EEC on hazardous waste, O.J. 6 September 2000, L 226/3.

Council Decision 2006/144/EC of 20 February 2006 on Community strategic guidelines for

rural development (programming period 2007 to 2013), O.J. 25 February 2006, L 55/20.



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2. Literature

Aguirre de Carcer D., Martin M. e.a. The introduction of genetically modified

microorganisms designed for rhizoremediation induces changes on native bacteria in the

rizosphere but not in the surrounding soil, The ISME Journal, 2007, 1, 215-23,

http://www.nature.com/ismej/journal/v1/n3/full/ismej200727a.html, last visited 10 May 2010.

BIOPROS, Solutions for the safe application of wastewater and sludge for high efficient

biomass production in Short-Rotation-Plantations, D4 – Report on ongoing research and

gaps in SRP knowledge, 14 February 2005, Sweden, February 2006, 44 p,

http://www.biopros.info/uploads/media/BIOPROS-D05.pdf, last visited 8 June 2010.

BIOPROS, Solutions for the safe application of wastewater and sludge for high efficient

biomass production in Short-Rotation-Plantations, D5 – Guidelines on safety issues for SRP

wastewater application, 14 February 2005, Sweden, February 2006, 22 p,

http://www.biopros.info/uploads/media/BIOPROS-D05.pdf, last visited 7 June 2010.

Bringezy S., Schutz H. e.a., Towards sustainable production and use of resources: Assessing

Biofuels, United Nations Environment Program, 2009,

www.unep.fr/scp/rpanel/pdf/Assessing_Biofuels_Full_Report.pdf, last visited 10 May 2010.

Dufey A., Biofuels production, trade and sustainable development: emerging issues,

International Institute for Environment and Development, London, 2006, 62 p.,

http://www.iied.org/pubs/pdfs/15504IIED.pdf, last visited 9 May 2010.

Duruibe J. O. e.a., Heavy metal pollution and human biotoxic effects, International Journal

of Physical Sciences, May 2007, Vol. 2 (5), pp. 112-118,

http://www.academicjournals.org/ijps/PDF/pdf2007/May/Duruibe%20et%20al.pdf (accessed

on 3 August 2010).

ECHA, Guidance for Annex V, Exemption from the obligation to register, March 2010,

version 1, http://guidance.echa.europa.eu/docs/guidance_document/annex_v_en.pdf (accessed

on 25 August 2010).

European Court of Justice 18 April 2002, case C-9/00, Palin Granit Oy.

European Court of Justice 25 June 1997, joined cases C-304/94, C-330/94, C-342/94 and C-

224/95, Euro Tombesi e.a.

European Center for Nature Conservation, The Pan-European Biological and Landscape

Diversity Strategy, Netherlands, Nature and Environment, 1996, 66 p,

www.coe.int/t/dg4/cultureheritage/nature/biodiversity/SN74_en.pdf, last visited 8 May 2010.

European Commission, Compost production and use in the EU, ORBIT e.V. / European

Compost Network ECN, 182 p.,

http://susproc.jrc.ec.europa.eu/activities/waste/documents/080229_EoW_final-

report_v1.0.pdf (accessed on 25 August 2010).

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European Commission, DG Agriculture and Rural Development, The Common Agricultural

Policy explained, May 2009, 11 p.,

http://ec.europa.eu/agriculture/capexplained/index_en.htm.

European Commission, Groundwater protection in Europe, European Communities 2008,

http//bookshop.europa.eu, 36 p., ec.europa.eu/environment/water/water-

framework/groundwater/brochure/en.pdf, last visited on 30 May 2010.

European Commission, Proposal for a Directive of the European Parliament and of the

Council establishing a framework for Community action to achieve a sustainable use of

pesticides, Brussels, 12 July 2006, COM(2006) 373 final,

ec.europa.eu/environment/ppps/home.htm, last visited 8 June 2010.

European Commission, Proposal for a Directive of the European Parliament and of the

Council establishing a framework for the protection of soil and amending Directive 2004/35/EC, Brussels, 22 September 2006, COM(2006) 232 final, eur-

lex.europa.eu/LexUriServ/LexUriServ.do?uri=COM:2006:0232:FIN:EN:PDF, last visited 30 May 2010.

European Commission, Report from the Commission to the Council and the European

Parliament on sustainability requirements for the use of solid and gaseous biomass sources in

electricity, heating and cooling, Brussels, SEC(2010) 65, 19 p.,

ec.europa.eu/energy/renewables/transparency_platform/doc/2010_report/com_2010_0011_3_

report.pdf, last visited 4 October 2011.

Florida Native Plant Society, Policy statement on Arundo donax , 9 p.,

www.fnps.org/committees/policy/pdfs/policyarundo_policy_statement1.pdf, last visited 8

June 2010.

Genovesi P., Shine C., European Strategy on Invasive Alien Species, Standing Committee of

the Convention on the Conservation of European Wildlife and Natural Habitats, Strasbourg,

5 December 2003, 50 p, www.jncc.gov.uk/pdf/BRAG_NNS_Genovesi&Shine-

EuropeanStrategyonInvasiveAlienSpecies.pdf, last visited on 9 June 2010.

Hoppenbrouwers M. and Vanheusden B., De relatie tussen de REACH-Verordening en de

(Europese) regelgeving inzake afvalstoffen, Milieu- en Energierecht, 2009, Vol. 4, p 243-254.

Institute for prospective technological studies, End of waste criteria, final report, European

Commission, Joint Research Centre, 2008, p. 48,

susproc.jrc.ec.europa.eu/activities/waste/documents/Endofwastecriteriafinal.pdf (accessed on

22 August 2010).

Invasive Species Specialist Group, IUCN, Guidelines for the Prevention of Biodiversity loss

caused by Alien Invasive Species, Approved by the 51st Meeting of the IUCN Council, Gland

Switzerland, February 2000, 24 p.,

intranet.iucn.org/webfiles/doc/SSC/SSCwebsite/Policy_statements/IUCN_Guidelines_for_the

_Prevention_of_Biodiversity_Loss_caused_by_Alien_Invasive_Species.pdf, last visited on

20 May 2010.

http://ec.europa.eu/environment/ppps/home.htm

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Jinga, V., Iliescu, H., Stefan, S., Manole, Response of some sunflower cultivars to broomrape

attack in Romania, HELIA 32, 10 November 2009, Nr. 51, p.p. 127-134.

Lasat M., Phytoextractio of metals from contaminated soil: a review of plant/soil/metal

interaction and assessment of pertinent agronomic issues, Journal of Hazardous Substance

Research, Volume 2, 2000, p 5-1,

citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.15.7236&rep=rep1&type=pdf, last

visited 24 May 2010.

Martin Junger Copernicus Institute, Lessons from (European) Bioenergy Policies - Results of

a literature review for IEA Bioenergy Task 40, Netherlands, September 2007, igitur-

archive.library.uu.nl/chem/2008-0423.../NWS-E-2007-122.pdf (accessed on 20 July 2010).

Meers E., Tack F., Van Slycken S., Ruttens A., Du Laing, J. Vangronsveld J., Verloo M.,

Chemically Assisted Phytoextraction, A Review of Potential Soil Amendments for Increasing

Uptake of Heavy Metals, International Journal of Phytoremediation, 10:390–414, 2008.

Möller R., Toonen M. e.a., Crop platforms for cell wall biorefening: lignocellulose

feedstocks, EPOBIO project, April 2007, University of York, 176 p.

Parris K. e.a., Biomass and Agriculture, Sustainability, Markets and Policies, OECD

Publications, 2003, 565 p,

www.oecdbookshop.org/oecd/display.asp?K=5LMQCR2JJ1S0&DS=Biomass-and-

Agriculture, last visited on 27 May 2010.

Rejuvenate, Crop Based Systems for Sustainable Risk Based Land Management for

Economically Marginal Degraded Areas, p. 19, www.snowman-

era.net/content.php?horiz_link=12&vert_link=0, (accessed on 24 August, 2010).

Science, Austria, Hungary Allowed to Keep Ban on Genetically Modified Crops, Deutsche

Welle, 2 March 2009, www.dw-world.de/dw/article/0,,4068097,00.html.

SMK, The European Eco-label user manual for Soil Improvers, The Netherlands, May 2006,

29 p.,

http://ec.europa.eu/environment/ecolabel/ecolabelled_products/categories/pdf/si_criteria2.pdf

.

SNOWMAN, The Second Snowman Coordinated Research Call, Sustainable Soil

Management, Applicants Guide, SnowmanERAnet, 10 December 2008, p 18.

SNOWMAN, Crop Based Systems for Sustainable Risk Based Land Management for

Economically Marginal Degraded Areas, Phase II: Demonstration projects and evaluation

decision support tool, Research Project Proposal, Rejuvenate 2, p 9.

Stein A. and Rodriguez-Cereso E., The Global Pipeline of new GM crops, implications for

asynchronous approval for international trade, JRC Scientific and Technical Reports, 2009,

Office for Official Publications of the European Communities, 113 p.

SUMATECS, Sustainable management of trace element contaminated soils –Development of

a decision tool system and its evaluation for practical application, Final Research Report,

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Vienna, December 23, 2008, 318 p, http://www.rhizo.at/default.asp?id=326 (accessed on 25

August 2010).

Vangronsveld J., Herzig R., Thewys T. e.a., Phytoremediation of contaminated soils and

groundwater: lessons from the field, Environ Sci Pollut Res 2009, Springer-Verlag, 16:765–

794.

Yuan Z. and VanBriesen J., Environmental Engineering Science. May/June 2006, 23(3): 533-

544, http://www.liebertonline.com/doi/abs/10.1089/ees.2006.23.533, last visited 29 May

2010.

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B. ECONOMIC ASPECTS

I. ECONOMIC MODEL BASED ON LITERATURE REVIEW

1. Conceptual framework

1.1 What Rejuvenate 1 started…

All across Europe there are areas of land which have been degraded by past use. In the EU there

may be up to three million potentially contaminated sites, over 80,000 sites have been cleaned up

over the past 30 years, while 250,000 polluted sites require urgent attention (EEA, 2007). The

Rejuvenate 1 project was a desk study carried out by r³ environmental technology ltd (UK), the

Swedish Geotechnical Institute (Sweden), Dechema e.V. (Germany), and Bioclear (The

Netherlands). It outlined the opportunity for growing renewable energy crops on marginal land

across Europe (in particular brownfields, and contaminated land), and provided a framework for

decision-making about (i) the use of marginal land for growing non-food crops for renewable

energy, and (ii) the simultaneous use of recycled organic matter for soil improvement.

The fundaments of this study were built on the fact that the combination of biomass cultivation

and soil remediation could be an important part of sustainable risk based land management where

the management strategy could become self-funding and could even result in other environmental

benefits such as carbon sequestration. Risk based land management refers to the fact that it is

necessary to consider to what extent toxic substances may harm human health or the wider

environment not only while in soil, but also after remediation. Risk management has as its main

aim to identify the different elements of the contaminant-pathway-receptor chain and to break

this chain. The pathway can be very diverse, but a common example is that the contaminants in

soil are taken up by vegetables which are directly consumed by humans. Or, after remediation,

contaminants might eventually end up at a disposal site. A remediation strategy is effective if it

minimizes or controls the health or environmental risks associated with a particular pollutant

linkage. By removing contaminant sources, breaking exposure pathways between source and

receptor, or changing the receptors, pollutant linkages are minimized (Mench et al., 2010). This

might therefore result in a management strategy that does not necessarily lead to a removal of

toxic substances.

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The decision support tool (DST) developed within Rejuvenate 1 takes into account the necessary

issues to break this chain of contaminant-pathway-receptor in a risk minimizing way. Therefore,

within Rejuvenate, the appropriate selection of crop types is based on climate conditions, site

contamination, site topography, available market for the crops, etc. Following the DST, this

should lead to a financially feasible soil management strategy. Moreover, the DST attempts to

achieve this within a sustainable way. This includes not only an analysis of the impact of the

strategy on biodiversity, water use, and energy use, but also an analysis of the effect of the

strategy on new pollutant linkages. E.g. remediation with crops results in enriched harvested

biomass which has to be used or disposed properly, a topic that was already considered, but not

yet completed within Rejuvenate 1. The model developed within Rejuvenate 1 resulted in Figure

0-1.

StartStart

Project Risk

Crop

Acceptable Value

Site

Crop Types

Climate/ Topography

Business use Options

Soil Characteristics

Risk Assessment

Project Impact

Economic

Environmental

Social

Technology Status

Detailed Dilligence

Stakeholder Views

Output: option for suitable crops and uses

Output: site management strategy

Output: best value approach

Output: project risk

assessed/ minimised

Figure 0-1 Decision support tool for sustainable contaminated land management

In Rejuvenate, partners with an expertise in different disciplines are working closely together to

come to an integrated, multidisciplinary framework. Multidisciplinary research teams and

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involvement of stakeholders are primordial for long-term ecological, ecotoxicological, social and

financial sustainability of phytotechnologies. However, what Rejuvenate 1 lacked was a practical

test of the decision tool. And this is where Rejuvenate 2 takes off.

1.2 … and Rejuvenate 2 continues

While the third work package will use the DST to select sites for establishing full scale case

studies in some of the participating countries, and the fourth work package will perform a SWOT

analysis of the DST, the fifth work package will assess the legal and economic feasibility of the

DST. The outcome of this work package will then be used as input for the former work packages.

More specifically, this first report will introduce some concepts that are primordial for a thorough

economic analysis. In this report, we specify the general economic outline of the DST that will be

followed in work package 5, and define a central question. To answer this question, we define

some concepts in more detail, based on a literature review. This literature review focuses on the

phytoremediation potential of specific crops, and the trade-off between biomass production and

phytoremediation. Moreover, we justify the use of these crops for energy purposes. We end our

literature review with the concept of Cost Benefit Analysis (CBA): its use, its advantages and

drawbacks, externalities, and its relation with sustainability. The findings of this first report will

then be used in the following report where we will assess the economic feasibility of

phytoremediation on contaminated sites, using the DST.

The problem of soil contamination is complex, often involving multiple stakeholders, but also

involving multiple layers. First, it concerns soil where conventional remediation techniques are

inapplicable due to different reasons. Therefore, phytoremediation is suggested as an alternative

remediation technology. Second, the damage has been done. The cases under consideration do

not handle avoiding (soil) pollution as an external cost of industrial activities, but rather deal with

this (soil) pollution as a resulting external cost of industrial activities, and mining. The analysis

focuses on the effects of soil pollution, and searches for an alternative valorisation for this land.

The consequential costs are not only borne by the liable agent (in most cases industry), but also

by the land owner and society. Third, the owner or tenant of the soil will bear the costs.

Consequences of remediation might not be as positive and clear-cut. It is very crucial to

understand and define what exactly the benefits might become for the owner or tenant since it is

these benefits that will motivate him. This is related to the fourth layer (legislation) as (European)

legislation on soil contamination and biomass faces multiple challenges. This is handled more in

detail in a separate part of work package 5. And fifth, there are additional effects resulting from

the clean-up of soil and this has consequences for social welfare. Today, it is widely recognized

that cleanup activities of hazardous waste sites may be the cause of external effects e.g.

greenhouse gases. In August 2009, the United States Environmental Protection Agency therefore

published its proposal called Superfund Green Remediation Strategy which outlines strategic

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recommendations for cleaner site redevelopment (EPA, 2009). The Rejuvenate approach intends

to grasp this multi layer attribute.

The Clarinet platform correctly pointed out that not all remediation projects are in itself

sustainable and might actually cause an economic, environmental, and social burden. In

December 2009, the European Common Forum and Nicole (Network for Industrially

Contaminated Land in Europe) published a position paper on innovative technologies. In their

paper it is argued that cost-effective and sustainable land management technologies are necessary

to deal with ever increasing soil management costs. Although the necessary in-situ techniques are

already available, their commercial implementation in Europe is low due to a lack of an action

plan. Many phytotechnologies for trace elements and other contaminants are at the demonstration

level, but relatively few have been applied in practice on large sites. More data are needed to

quantify the underlying economics as a support for public acceptance and to convince policy

makers and stakeholders (Ruttens and Vangronsveld, 2006; Adriaensen et al., 2008;

Vangronsveld et al., 2009).

Indeed, there still is a gap between research and development for the use of phytoremediation at

field level, which is partly due to:

- a lack of awareness by regulators and stakeholders (e.g. land owners, tenants);

- a lack of expertise and knowledge by service providers and contractors;

- uncertainties in long-term effectiveness (what is still available?, monitoring); and

- difficulties in the transfer of particular metabolic pathways to productive and widely available

plants (Adriaensen et al., 2008).

Therefore, a clear road map for utilisation of phytotechnologies needed to be developed to allow

the user to make an informed decision on the most suitable technology for the site requiring

remediation or management (Adriaensen et al., 2008). The sustainable management of trace

element contaminated soils (SUMATECS) program showed a clear desire amongst stakeholders

for a reliable decision system tool and improved decision support for gentle remediation

operations (GRO) and recommended the incorporation of GRO-focused decision support into

national guidelines/tools. This decision tool should consider overall life cycle costs, benefits, and

risks, specific to the site conditions. Rejuvenate 1 already made a first step in developing a

decision tool.

Phytoremediation undoubtedly has a high potential to enhance the degradation and/or removal of

organic contaminants from soils (Vangronsveld et al., 2009; Weyens et al., 2009, 2010).

However, based on extrapolations of data obtained from pot experiments, enthusiastic

interpretations and promises have been made concerning the possibilities of phytoextraction (Salt

et al., 1995; Rulkens et al., 1998; Susarla et al., 2002; Mench et al., 2010). Therefore, more

demonstration projects on phytoextraction are required to provide recommendations and

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convince regulators, decision makers, and the public of the applicability of phytoremediation for

the treatment of soils, brownfields, groundwater, and wastewater contaminated with diverse

pollutants (Vangronsveld et al., 2009). Therefore, the decision tool which has been developed by

Rejuvenate 1 is tested and specified more in detail in Rejuvenate 2.

1.3 Decision tool specifics (work package 5)

1.3.1 General outline

Within the project proposal of Rejuvenate 2, the economic assessment includes the potential

economic value of a biomass on marginal land approach, with an estimation of the relevant

internal and external costs for different stakeholders, and taking into account transport costs.

Based on this, work package 5 of Rejuvenate 2 will focus on the following question:

Does phytoremediation, as a multifunctional and sustainable alternative for conventional

remediation technologies for functional restoration of contaminated soil, result in

economically optimal remediation strategies?

- does phytoremediation offer an economically viable alternative for conventional remediation

technologies and which crops should be used and under what circumstances? The analyses in this

study are based on a cost-benefit analysis with net present value (NPV) as the decision tool.

- does phytoremediation result in other than private costs and benefits and if so, are these

externalities positive or negative? The resulting biomass could be used for renewable energy

purposes, but also results in heavy metal waste disposal. Both are considered externalities of

phytoremediation and should be internalized in the decision model through the correct policy.

In a first phase, the quantification of the different benefits of the multifunctional land use requires

the identification of physical terms. Crop choice will be based on the DST of Rejuvenate 1. This

involves the determination of (i) current characteristics of the soil. In a next step (ii) different

remediation options as to crop choice are defined. Each of these crops will result in different

accumulation of heavy metals, different revenues, different energy production, different CO2

abatement potential, and different by-products after conversion. In a last step, finally aimed levels

of contamination (iii) are determined based on all kinds of legislation. In a second phase, physical

data are combined in a (business) model by giving them an economic value in a CBA. Based on

the start- and end level of contamination, remediation has different time ranges, depending on the

used crop. Total economic value is then calculated as the sum of revenues resulting from the

remediating crops, and revenues from activities after remediation, over an infinite time range,

based on market prices.

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However, market prices do not always correctly reflect consumer’s willingness to pay (WTP). An

activity may generate impacts that spill over to other economic agents. These spill-overs or

externalities can either be negative (heavy metal in rest product) or positive (CO2 abatement from

green energy production). Other external effects (e.g. biodiversity) could also be considered in

Rejuvenate 2.

Once the stream of economic costs and benefits is estimated, the standard NPV methodology is

applied, using a social discount rate of 4%.

1.3.2 Model specifics

In Figure 0-2, AGIrem represents yearly adapted gross income during remediation from time 0

until time x. AGIHI represents yearly adapted gross income from high income (HI) activities after

remediation from time x until ∞. NPV of AGIrem from time x to time 0 is equal to A. NPV of

AGIHI from ∞ to time x is equal to B. To sum A and B, the latter is first discounted to time 0.

Figure 0-2 Model scheme, with the income during (A) and after (B) remediation, starting

from C0

Two trade-offs exist (Figure 0-3). There is (i) the trade-off between higher income during

remediation and faster remediation, as these do not necessarily go hand in hand. Given a HI

activity that is allowed from Cx, faster remediation has the advantage of faster allowing for this

HI activity (at time t1 instead of time t2). The income of this HI activity at an earlier stage might

then compensate for the lower income during remediation. There is also (ii) the trade-off between

different HI activities: they are allowed at different maximum allowed contaminant

concentrations in soil (C1 versus C2), and therefore the choice for one or the other HI activity has

€

A G I H I

0

A

B

x t i m e

A G I r e m

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an influence on remediation duration. Again, the income of a HI activity starting at a later time

(starting from time t2 at concentration C2) has to make up for the lower income during

remediation and there is no necessary positive relation between lower Cx and higher income of

the HI activity.

Figure 0-3 Trade-offs in phytoremediation model, with (i) trade-off between fast and high

income remediation, and with (ii) trade-off between high Cx and high income for HI activity

(i) (ii)

C

C0

Cx

0 t1

a b

t

C

C0

C2

0 t1 t2

a1

a2

C1

tt2

2. Literature review

From the model described above, it is clear that the economic analysis needs a lot of technical

input. This report builds the fundaments for the analysis which will be actually performed in the

next report of work package 5. First, we give an overview of different types of phytoremediation

crops and the impact of choice on remediation duration and thus economics (since a high income

activity can only be performed after remediation). Next, we convince the reader that for the

moment the use of these crops for energy purposes is most suitable. We end our literature review

by explaining the economics behind the analysis and why an economic assessment is necessary to

assure sustainability.

2.1 Phytoremediation

Phytoremediation is defined as “bioremediation by using plants, applicable for the removal or

degradation of organic and inorganic pollution in soil, water and air”. It uses plants to remove

pollutants from the environment or to render the pollutants harmless. Within this domain,

phytoextraction is defined as the use of plants for the effective removal of pollutants (metals and

organics) from soil. Figure 0-4 below summarizes advantages and disadvantages of conventional

and phytoremediation techniques.

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Figure 0-4 Comparison of conventional and phytoremediation techniques for heavy metal

soil remediation

Source: Witters et al. (2009)

2.1.1 Remediation duration

Total contaminant removal rate and resulting remediation duration depend on soil characteristics,

level of contamination, available contamination, crop extraction, and crop biomass production

(Koopmans et al., 2008). When contaminants are removed, the total amount of contamination

reduces, as well as the amount of available contaminants. This relation can be linear but is in

most cases logarithmic, meaning that the amount of available contaminants reduces faster than

the amount of contamination, reaching a limit amount of available contaminants. Over time,

contaminant concentration in the plant (Ei) is then affected by the amount of available

contaminants in soil over time. However, some authors describe a replenishment of the available

contaminant pool (Van Nevel et al., 2007). This is e.g. the case for sandy soils. Also, biomass

production of the plant (BPi) might change over time. E.g. the biomass potential of short rotation

coppice (SRC) of willow, BPW, might increase after several years within a rotation cycle,

whereas the biomass production of energy maize or rapeseed (BPEM or BPRS respectively) might

decrease in time (due to nutrient depletion). Moreover, the depth of the rooting zone might be a

factor that influences contaminant concentration in plants, as concentration found in plants might

differ according to root depth. Finally, there could also be leaching losses to the groundwater

(van der Grift and Griffioen, 2008).

Conventional remediation

Excavation

Ex situ treatment

Treatment or disposal

+Serious contamination

+Quick remediation

-For concentrated contamination

-Suitable for small surfaces

-Loss of soil structure

-High cost

Phytoremediation

Use of plants

In situ treatment

Use for energy, material

-Moderate contamination

-Slow remediation

+For diffuse contamination

+Suitable for large surfaces

+Keeps soil structure

+Cost similar to farming cost

Contaminated soil

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A key question which has been in debate since the very beginning of the introduction of the trace

element phytoextraction concept is: “Should one use trace element hyperaccumulator plants or

high biomass producing plants?” Opposite opinions exist. Chaney et al. (1997) favored the

former choice after they hypothetically calculated Zn removal by hyperaccumulator and high

biomass plants and concluded that in any case the use of hyperaccumulators resulted in higher

trace element removal. In support of the second option, Kayser et al. (2000) reported that the

trace element removal capacity of T. caerulescens was not very different from that of biomass

producing crop species used. Ebbs et al. (1997) supported the latter authors after observing ten

times higher Cd concentrations in T. caerulescens, but also ten times less biomass production as

compared to biomass producing crops. Obviously, the choice for the first or second option

depends on site characteristics. If crops would suffer from toxicity problems, hyperaccumulators,

which in general possess a higher trace element tolerance, should have an obvious advantage. If

high biomass crops are chosen, the most suitable one again depends on general site characteristics

(Vangronsveld et al., 2009).

REMi= A . d . ρ . (Cq – C0) = Qq – Q0 (Eq. 1)

REMi = A . ti . BPi

. Ei (Eq. 2)

ti = (Qq – Q0)/(BPi . Ei) (Eq. 3)

The total amount of trace elements to be removed per hectare by crop i (REMi) is the difference

between the amount initially present in the soil of the polluted site (Q0) and the amount in soil for

which it is allowed to perform a HI activity (Qq), or in general, the final amount of trace elements

in soil that is economically most viable (Qx). The total initial amount (Q0) is calculated as the

product of soil depth (d), soil density (ρ), the area surface (A), and initial concentration of trace

elements in soil (C0). Likewise, the final amount in soil (Qq) is based on Cq (Eq. 1).

REMi is also equal to the plant biomass production per hectare per year (BP i) multiplied with the

contaminant content in the harvested plant biomass (Ei), the number of years of plant growth (ti),

and the area surface (A) (Eq. 2). Substituting REMi from (Eq. 1) in (Eq. 2), the time (ti) needed to

remediate one hectare of soil up to a level Cq can be calculated (Eq. 3) (Japenga et al., 2007).

The remediation duration (ti) of crop i in years is presented in (Eq. 3) as the amount of obliged

contaminant (g ha-1) removal (Qq –Q0) divided by the product of yearly biomass potential of crop

i (ton ha-1 y-1) (BPi) and concentration of contaminant in crop i (mg kg-1) (Ei). BPi and Ei are here

considered as constant. However, both depend on soil characteristics and available contaminant

concentrations in soil and might change as contaminant concentration in soil decreases.

Therefore, in practice, this basic linear calculation of ti which assumes that BPi and Ei remain

constant over time might be an underestimation of reality, i.e. actual remediation might take

longer.

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2.1.2 Hyperaccumulators

Research on the phytoextraction potential of plants started with hyperaccumulating plants (Salt et

al., 1995; Chaney et al., 1997). Species such as alpine penny cress (Thlaspi caerulescens) with

natural metal accumulating characteristics were used for phytoremediation (Garbisu and Alkorta,

2001; Vassilev et al., 2002).

The first field experiment using natural hyperaccumulator plants was performed in 1991-1992 in

sewage sludge treated plots at Woburn, UK (McGrath et al., 1993). The highest Zn uptake was

observed in T. caerulescens accumulating 2,000 to 8,000 mg Zn kg-1 dm in shoots when growing

on soil containing total Zn concentrations of 150-450 mg kg-1. The total Zn uptake was calculated

to be 40 kg ha-1 in a single growing season. With this extraction rate it was concluded that it

would take nine crops of T. caerulescens to reduce total Zn from 440 to 300 mg kg-1 – the

threshold value established by the European Commission at that time. In a field trial supervised

by Chaney et al. (1995, 1997, 1999) at Pig’s Eye landfill site in St-Paul (Minnesota, USA) it was

found that under optimum growth conditions T. caerulescens could take in Zn at a rate of 125 kg

ha-1 y-1 and Cd at 2 kg ha-1 y-1 (Saxena et al., 1999). Robinson et al. (1998), on the basis of both

field observations and pot-soil experiments, concluded that the potential of T. caerulescens for Zn

and Cd extraction is rather different. They reported Zn removal values very close to that observed

by McGrath et al. (1993) and suggested that it will be not feasible to remediate the Zn

contaminated mine wastes, because of both their high Zn content and low Zn bioaccumulation

factor. They considered the case of Cd as different due to very high Cd accumulation in leaves of

T. caerulescens (0.16%) originating from Ganges (France) and comparatively lower Cd

contamination, especially in some agricultural soils, where phosphate fertilizers have been

applied for long period.

If the high trace element concentration (Zn, Cd) of T. caerulescens is an advantage, its slow

growth rate, low dry matter yield and rosette characteristics are main limitations (Ernst, 1998;

Assunçao et al., 2003). Field observations and measurements on natural populations of T.

caerulescens have shown that these plants have an annual biomass production of 2.6 ton ha-1

(Robinson et al., 1998). Kayser et al. (2000) reported a maximum yield from T. caerulescens of

about 1 ton ha-1 under field trails due to poor growth and weak resistance to hot environment. On

the other hand, Bennett et al. (1998) showed that the yield of fertilized crop of T. caerulescens

could be easily increased by a factor of 2 - 3 without significant reduction in Zn and Cd tissue

concentrations. More recently, Schwartz et al. (2003) showed evidence for this statement

observing that Zn and Cd extraction by T. caerulescens has been improved significantly by

nitrogen fertilization (80 - 200 mg N kg soil-1). Zhao et al. (2003) suggested that an average T.

caerulescens biomass of 5 ton ha-1 should be achieved with optimized agronomic inputs.

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It is clear that the biomass potential of most hyperaccumulating species is limited, and moreover,

metal accumulation is species- and even ecotype specific, and there still is a lack of knowledge

concerning agricultural practices and management (Salt et al., 1995; Garbisu et al. 2001; Lombi

et al., 2001; Vassilev et al., 2002, 2004; Van Nevel et al., 2007; Vangronsveld et al., 2009;

Zhang et al., 2009).

Therefore it was suggested that, besides accumulating reasonable amounts of metals into their

above ground biomass, plants used for phytoextraction should tolerate relatively high levels of

metals in the soil, while maintaining rapid growth rates and reaching a reasonably high biomass

in the field (Alkorta et al., 2004; Hernández-Allica et al., 2008).

2.1.3 Biomass producing crops

More recently, fast-growing crops with greater biomass potential such as willow (Salix spp.),

poplar (Populus spp.), maize (Zea mays), and rapeseed (Brassica spp.) have been tested for

phytoremediation, resulting in a final extraction that can be equal to hyper-accumulating plants,

despite the lower trace element concentrations in their tissues (Vassilev et al., 2002; Chaney et

al., 2004; Hernandez-Allica et al., 2008; Ruttens et al., 2010).

In Europe, the production of energy maize is increasing rapidly. The biomass resulting from this

crop can be applied for conversion into biogas through anaerobic digestion. As such, energy

maize and biogas production represent a new branch of agriculture, which has been emerging at

large-scale over the past five to ten years (Meers et al., 2010). Although some authors report that

in comparison to other plant species, maize is a rather good accumulator of Pb (Garbisu and

Alkorta, 2001; Chrysafopoulou et al., 2005), other authors find that it does not actively take up

trace metals (Zhang and Banks, 2006). Meers et al. (2005) found that, out of four high biomass

producing crops, i.e. Brassica rapa (rapeseed), Cannabis sativa (hemp), Helianthus annuus

(sunflower) and maize, the latter exhibited the highest biomass potential on moderately metal

contaminated land, with the lowest metal accumulation (Cd, Pb, Zn) in the harvestable plant

parts. Although metal accumulation by maize can be chemically enhanced, phytoextraction as a

remediation tool will still take an extensive period of time (years to decades, depending on the

amount of metals that need to be extracted). Therefore, a new “term” for phytoremediation is

proposed: phytoattenuation (Meers et al., 2010). The main focus lies on risk reduction in

utilization of metal-enriched land. This can be achieved by using crops with high biomass

production potential, low metal concentration in plant parts (by using an excluder species) while

allowing a maximum economic valorization of land. This is why alternative use and valorisation

of the produced biomass may become a prerequisite for field-scale application of phytoextraction

as a remediation technique (Meers et al. 2006).

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Previous research indicated that willow can survive on metal-enriched soils (Pulford and Watson,

2003; Meers et al., 2007). Its Cd accumulation potential has already been investigated widely

(Berndes et al., 2004; Mirck et al., 2005; Lewandowski et al., 2006) as well as its contribution to

integrated brownfield redevelopment (French et al., 2006). Because of the multiple

environmental benefits (Borjesson, 1999a, 1999b) associated with woody crops grown on short

rotations, increasing interest over the world can be noticed. Willow has several characteristics

that make it ideal for short rotation cycles including high yields obtained in a few years, ease of

vegetative propagation, a broad genetic base, a short breeding cycle, and the ability to resprout

after multiple harvests (Kopp et al., 2001; Volk et al., 2004). Its full environmental potential

(Kuzovkina and Quigley, 2005) and economics have already been studied in Sweden (Rosenqvist

et al., 2000), Ireland (Rosenqvist and Dawson, 2005), Finland (Tahvanainen and Rytkonen,

1999), Poland (Ericsson et al., 2006), Germany (Scholz and Ellerbrock, 2002), United States

(Adegbidi et al., 2001; Keoleian and Volk, 2005) and the UK (Mitchell et al., 1999).

Experimental plantings of SRC of willow have occurred recently (Van Ginneken et al., 2007;

Ruttens et al., 2008; Meiresonne et al., 2009). SRC of poplar has been indicated by the Institute

for Nature and Forest as having the right characteristics to serve as a remediating crop

(Meiresonne, 2006).

Recently, fast-growing high biomass crop plants that accumulate moderate levels of metals in

their shoots are being tested for their metal phytoextraction potential. Rapeseed (Brassica napus)

has been type casted as an above average accumulator of heavy metals (Bernhard et al., 2005;

Selvam and Wong, 2009; Shi and Cai, 2009). Therefore, crops from the Brassica family have

already been suggested for phytoremediation (Marchiol et al., 2004). Field experiments confirm

that certain rapeseed crops are suitable for phytoextraction of moderately heavy metal

contaminated soils. Moreover, crops from the Brassica family display a significant heavy metal

tolerance (Bernhard et al., 2005; Hernandez-Allica, 2008; Shi and Cai, 2009). Grispen et al.

(2007) conducted a screening for natural variation in Cd accumulated by 77 Brassica napus. This

yielded potential candidates for phytoextraction in agricultural practice. After harvest, rapeseed

results in rich oil containing seeds, and straw. The seeds could be sold for biodiesel production.

2.2 Biomass for energy

If produced phytoremediation biomass can be valorised into an alternative income, then the main

drawback of phytoextraction, namely the extended remediation period required, may become

invalid and slower working phytoremediation schemes based on gradual attenuation of the

contaminants rather than short-term forced extraction may be envisaged (Robinson et al., 2003).

Conventional remediation techniques will take less time, but during remediation it will not be

possible to validate the soil. When phytoremediation is implemented, the repeated cropping of

plants produces high amounts of biomass which need to be disposed of or better, treated

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appropriately to prevent any risks to the environment (Ghosh and Singh, 2005). The utilization of

the obtained biomass of a phytoextraction cycle as an energy resource is therefore attractive

(Chaney et al., 1997) and can even turn phytoextraction into a profit making operation (Meers et

al., 2005). Moreover, using the resulting biomass for energy may contribute to the reduction of

global carbon dioxide (CO2) emissions. Biomass can replace fossil fuels for the supply of heat,

electricity and transport fuel, and can also serve as a feedstock for material production (Dornburg

and Faaij, 2005). As mentioned by Firbank (2008), one factor that drives the growth of

alternative crops for energy is the fact that they deliver an environmental benefit by reducing

greenhouse gas (GHG) emissions.

Within Rejuvenate 1 we chose for energy conversion as a sustainable alternative for several

reasons. First, energy production will more likely get public approval, opposed to other

destinations (e.g. paper mills). In Europe, farmers are variously rewarded for direct positive

contributions to biological diversity (particularly wildlife habitat), improvements (or avoided

negative impacts) to water quality and increased soil health through the concept of cross

compliance in the European Common Agricultural Policy (CAP). Many countries also support

bioenergy programs, with the intent to promote the production and use of cleaner fuels instead of

fossil fuel. Moreover, on a global scale, the increasing interest in carbon sequestering effects of

many types of agriculture points to a growing number of programs in the near future that will

support certain farming practices as a way of improving overall air quality (DeVries, 2000).

Second, energy conversion installations are able to trace heavy metals within their system. At

least, as far as we know there is research on this matter in the energy sector, but there has been no

research yet on tracing heavy metals in other biomass using technologies (e.g. paper mills).

2.3 Cost Benefit Analysis (CBA)

A lot of tools are available to perform an economic analysis. Decision science has not yet

developed a universally accepted methodology free from criticism for analyzing social decisions

involving risk. Explaining why we choose for CBA would lead us too far. Suffice it to say that

CBA is a useful and popular tool, aside from cost-effectiveness analysis, multi-criteria (decision)

analysis, risk assessment and environmental impact assessment (Kotchen, 2010). In the following

section, we will explain the logic behind CBA and its decision tool (NPV), its relation with

externalities (an important aspect within this study), and its alternatives. We end by explaining

the economic rationale behind sustainability and its relation with policy development.

2.3.1 Theory

The central premise of Cost Benefit Theory (CBT) is that alternatives are ranked according to a

systematic comparison of advantages (benefits) and disadvantages (costs) that result from the

estimated consequences of the alternative. Thus, the theory does not involve the concept of a

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social decision maker with special responsibility for the decision. On the contrary, individuals are

assumed to be the appropriate judges for valuing consequences. A best alternative is then defined

in terms of efficiency, i.e. it maximizes total surplus to society (Merkhofer, 1987; Hanley, 2000).

CBA approaches strive to implement the efficiency criterion of CBT by investigating whether the

consequences of an alternative are likely to increase efficiency. NPV functions as a decision

criterion for maximizing efficiency, under the assumption of a perfect market. Other decision

criteria are the Internal Rate of Return, or the Benefit Cost Ratio.

NPV is found by multiplying benefits and costs at (the end of) each year t by a time dependent

weight. As all effects will not occur in one year, but over several years (t: 0,…n) and as people

prefer one unit today rather than tomorrow, time preferences are taken into account, and yearly

benefits and costs are discounted using a discount rate (r). A capital sum in the initial year of

investment will not have to be discounted, except when it is converted into an annual capital cost.

To account for inflation, real or nominal values can be used, as long as they are used consistently.

Option 1 is then preferred over option 2 if (Eq. 5) holds149.

NPV= (Eq. 4)

NPV1>NPV2 (>0) (Eq. 5)

In a perfectly competitive market, prices have three functions that guide consumers and

producers up to the point that maximizes social welfare. First, they allocate goods to agents that

value them most highly. Second, they inform on the relative scarcity of goods. Third, they

provide incentives to use more or less of a good and to move towards the point of maximum

efficiency (Graves, 2007). In a perfect market, a producer will supply goods as long as marginal

production costs for an extra good lie below the price paid for the good. A consumer will

continue to buy a good as long as its marginal benefit exceeds the price. The self-interest of both

consumer and producer leads, guided by the invisible hand, to an equilibrium market price and an

equilibrium quantity of goods exchanged. In a system with well defined property rights and

competitive markets, producers and consumers maximize their private surpluses. The price

system then induces the self interested parties to make choices that are socially efficient.

Therefore, in a perfect market150, government intervention would not improve social welfare. The

decision analysis as described above will only lead to a completely efficient allocation of

149

An alternative indicator commonly used is the Internal Rate of Return (IRR). IRR can be calculated as the r for

which NPV=0. An investment is then accepted when IRR≥I, I being the required return rate. Option 1 is then

preferred over option 2 if IRR1>IRR2 (≥i). The benefit cost ratio is the ratio of discounted benefits to discounted

costs and the decision rule is to proceed when this ratio ≥ 1 (Hanley, 2000). 150

In a perfect market there are no public goods, no externalities, no monopoly buyers and sellers, no increasing

returns to scale, no information problems, no transaction costs, no taxes, no common property and no other

distortions between costs paid by buyers and benefits received by sellers (Fullerton and Stavins, 1998).

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resources within a perfect market. However, if the market for a commodity is distorted in any

way, prices might not reflect an individual’s WTP (Tietenberg, 2003).

Inefficient outcomes occur when the market structure is imperfect and when property rights151 are

not properly defined, resulting in externalities (and public goods). By some, these are called

market failures, others prefer the term missing markets, and missing markets always lead to

resource misallocation. Externalities occur when the condition of exclusivity is violated, leading

to an output of a given commodity that is too large. Public goods occur when in the absence of

exclusivity each person is able to become a free rider on another person’s contributions

(Tietenberg, 2003; Graves, 2007).

2.3.2 Externalities

According to economic theory, an individual whose initial desire for a commodity exceeds its

price will continue to purchase the commodity until the benefit derived from the last amount

purchased equals the price paid for that amount. When externalities are present this will lead to

an over- or underconsumption and over– or underproduction of the good, leading to a total social

surplus that is diminished with a dead weight loss. As a result, the free market does not produce

an efficient level of welfare (Merkhofer, 1987; Graves, 2007). An example of an externality can

be found in the potential CO2 abatement of biomass based energy. The external effect might not

be correctly reflected in the price of biomass if there is no (appropriate) policy. So, when

externalities exist, government may be justified in intervening to force a level of welfare that is

more socially desirable than the inappropriate one reached through the market. One way for

government to change human behavior is through the implementation of mandatory standards

and regulations or market oriented incentives designated to force individuals to take actions that

lessen risk (Merkhofer, 1987).

Lofgren (2000) distinguishes between private and public externalities. Many externalities have

the character of a public good, they have an effect on all of us and the consumption of the

externality by one of us does not lead to less consumption by others. Again, we can take the

example of CO2 emission by burning fossil fuel. The emission affects all of us and by burning

biomass based fuel, we avoid these emissions. Therefore we can say that the CO2 abatement by

producing energy from biomass is an externality with a public character. Heavy metals in by-

products from biomass based energy production could be defined as examples of private

externalities. If the by-products after energy production are not managed properly, metals might

151

A property right is a bundle of entitlements defining the owner’s rights, privileges and limitations for use of the

resource. An efficient structure of property rights has three characteristics. Exclusivity points to the fact that all

benefits and costs that result from using or owning a resource should accrue to the owners alone. Transferability of

the rights should exist between owners on a voluntary basis. Enforceability means that there is no intrusion by others.

When these conditions are fulfilled, an agent that holds a property right on a resource will use this resource the most

efficient as possible because a loss in value of the resource is a personal loss (Tietenberg, 2003).

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end up on the land again and be recycled in the food chain, affecting local people. This

distinction between private and public externalities is important up to the point that it might give

an indication of the extent to which policies are easier to implement. Intuitively, it seems easier to

develop and integrate a policy that handles local, private externalities. However, the general

underlying assumption of social welfare maximization is indifferent between private and public

external effects and we will not distinguish between them.

Policy instruments to internalize externalities require measuring the damage done or benefits

caused by the production and consumption of environmental goods and services. Since

environmental problems are very often caused by the fact that they are not valued appropriately,

the valuation of environmental goods should take a prominent place in the discussion of these

policies.

Q1Q*

Marginal revenue

FF

G

Q

Marginal private cost

Marginal social cost

E

H

P*

P1

P3

P

P2

Figure 0-5 Illustration of an externality

Source: based on EPA (2000)

Vatn and Bromley (1997) state that the term market failure is an unfortunate choice as

externalities are a rational result of the market as such, i.e. the absence of properly defined

property rights are common to most markets. An external effect occurs when the utility of one

consumer is affected by the consumption or production of another consumer or producer

(Johansson, 1987). Or, an externality exists if the production or consumption of a product

generates costs or benefits to others which are not reflected in prices. The prices that consumers

face do not reflect true social values.

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The situation before policy implementation results in marginal revenue and private marginal

costs intersecting at price P1, leading to consumption of private good Q1 (Figure 0-5). The

producer surplus at this point is P1GP2, consumer surplus is P1GP3. Because of the externality,

there is a social damage of P2FG (including a dead weight loss of EFG). The net social welfare is

then P2EP3 – EFG. Through introduction of the correct policy, the optimal Q* is now determined

by the intersection of the marginal revenue curve with the marginal social cost curve. The

producer surplus is now P2EP*, whereas consumer surplus is P*EP3. The net social welfare is

now P2EP3. Although there is a decrease in producer- and consumer surplus, the overall social

welfare has increased because of the reduction in external costs. There is no longer a dead weight

loss due to inefficient consumption and production of a good.

2.3.3 Non-economic valuation

Most economists would argue that economic efficiency ought to be one of the fundamental

criteria for evaluating regulations on environment. Society has a limited amount of resources, and

CBA is able to explicitly define the trade-offs to make the decision or regulation that will lead to

the highest social surplus. Arrow et al. (1996) suggest that although CBA should play an

important role in environmental decision making, it should not be the sole base. Suggestions are

made that CBA could and should be supplemented with a technique to measure environmental

costs in other than monetary terms (Joubert et al., 1997; Mirasgedis and Diakoulaki, 1997).

Multi Criteria Decision Analysis (MCDA) is the term used to include all the methods that

incorporate multiple criteria when helping decision makers in their problem solving. Criteria are

defined as measures of performance by which alternatives are judged. A final score for each

option is calculated based on aggregation of performances on all criteria and weights for each of

the criteria. This phase depends heavily on the technique by which the weights are derived, and

the aggregation method. However, to the best of our knowledge, it has not yet been used to assess

crop choice for contaminated land remediation. Advantages of MCDA methods are the ability to

include monetary and non-monetary measures of objectives, and to include a wide range of

objectives. However, MCDA techniques are not supported by a coherent theory of social welfare,

weights do not represent consumer preferences and depend on the decision maker, and often are

black boxes as they generate one number and seem complicated to the outside world (Hanley,

2000).

2.3.4 Sustainability

We end this report by putting the economic analysis within the framework of sustainability and

we provide a short link with policy development. Sustainability can be defined as an obligation to

conduct ourselves so that we leave to the future the option or capacity to be as well off as we are,

so that we can afford to please ourselves as long as this is not at the expense of future well-being

(Solow, 1991). Sustainability is a basic principle in the proposal for a Soil Framework Directive.

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Its preparatory document (Van Camp et al., 2004) states that soil is essentially considered a non-

renewable resource because the degradation rates can be rapid while the formation and

regeneration processes are extremely slow. The main question then is how to allocate between the

different generations.

The concept of sustainability can be broken down in 2 components: intergenerational equity and

dynamic efficiency. Intergenerational equity on the one hand emphasizes the ability of the

economy to maintain living standards, i.e. intertemporal152 social welfare (Vt) should not

decrease over time. This is the concept as embraced in the Brundtland Report. Resources are

substitutable, suggesting that we do not owe the future any particular good or any particular

natural resource. What we are obliged to leave behind is a generalized capacity to create well-

being. If this principle is accepted, we end up in the world of substitution and trade-offs.

However, it stays rational and logical to want to preserve a particular environmental good or

service, but not under the heading of sustainability. Dynamic efficiency on the other hand focuses

on maximizing Vt (at every time period t), i.e. the integral of discounted values of current and

future utility from society’s aggregate consumption from time t to infinity. In maximizing this Vt,

there is an optimal consumption path to be followed. Current consumption is excessive when it

lies above the level of current consumption prescribed by this path. An economy is sustainable if

and only if it is dynamically efficient and if the stream of maximized welfare is not decreasing

over time. This is a rather demanding definition and is hard to be achieved by public policy.

Economic maximization does not necessarily lead to sustainability.

Current environmental protection tries to withhold us from burdening the environment, from free-

riding on the future. It is basically a problem of savings and investment. In this respect, it can be

argued whether the goal of sustainability could be left entirely to the market. Correct

environmental policy setting is important. Standard policy remedies for improving only economic

efficiency do not guarantee sustainability. At the same time, such policies do not necessarily have

to conflict with the sustainability concept. Of course, we will make mistakes designing policies.

We will attribute to the future wrong tastes and excessive or undervalued technological

capacities. Ecologists often argue that certain natural resources are undervalued, because

economists are too optimistic about substitutes for these resources. When natural resource inputs

are priced below social cost, the overall level and composition of consumption can lead to

excessive natural resource use. On the other side, it is still possible to perform the social CBA to

see whether a policy at least increases intertemporal social welfare. However, all these

considerations should not abstain us from making policies, the guesswork has to be done, as we

will chose policies to avoid potentially catastrophic errors (Solow, 1991, 1992; Arrow et al.,

2003).

152

Intertemporal welfare deals with the distribution of welfare between the current time and the future , whereas

intratemporal welfare deals with the distribution within one time period, the equity issue (Arrow et al., 2003).

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II. ECONOMY, ENERGY AND WASTE DISPOSAL

1. Introduction

1.1 Model outline

The combination of biomass cultivation and soil remediation could be an important part of

sustainable risk based land management where the management strategy could become self-

funding and could even result in other environmental benefits such as carbon sequestration. Risk

based land management refers to the fact that it is necessary to consider to what extent toxic

substances may harm human health or the wider environment not only while in soil, but also after

remediation.

A remediation strategy is effective if it minimizes or controls the health or environmental risks

associated with a particular pollutant linkage. By removing contaminant sources, breaking

exposure pathways between source and receptor, or changing the receptors, pollutant linkages are

minimized (Mench et al., 2010). This might therefore result in a management strategy that does

not necessarily lead to a removal of toxic substances. A remediation strategy is efficient if the net

benefit of risk attainment is maximized. To calculate the optimal point of risk control, we should

place an economic value on the risk, and we should value the benefit. We use this approach by:

- comparing the value of land (measured by the agricultural income earned on the land) before

and after remediation (based on private costs and benefits);

- including the external benefit of CO2 abatement (by renewable energy production); and

- including the external cost of contaminants in the biomass.

As mentioned in the previous chapter, it is very crucial to understand and define what exactly the

private and social benefits might become since it is these numbers on which the owner or tenant

will base its decisions whether to remediate the land or not, and with what technology. Primordial

in this matter is current and future legislation on soil contamination, remediation, energy, and

biomass and waste. We focus on the following question:




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- does phytoremediation offer an economically viable alternative for conventional remediation

technologies and which crops should be used and under what circumstances? The analyses in this

study are based on a cost-benefit analysis with net present value (NPV) as the decision tool.

- does phytoremediation result in other than private costs and benefits and if so, are these

externalities positive or negative? The resulting biomass could be used for renewable energy

purposes, but also results in metal waste disposal. Both are considered externalities of

phytoremediation and should be internalized in the decision model through the correct policy.

In a first phase, the quantification of the different benefits of the multifunctional land use requires

the identification of physical terms. Crop choice will be based on the DST of Rejuvenate 1.

Based on current characteristics of the soil different remediation options concerning crop choice

are defined. Each of these crops will result in different accumulation of metals, different

revenues, different energy production, different CO2 abatement potential, and different rest

products after conversion. Physical data are combined in a (business) model by giving them an

economic value in a CBA. CBA approaches strive to implement the efficiency criterion of CBT

by investigating whether the consequences of an alternative are likely to increase efficiency. NPV

functions as a decision criterion for maximizing efficiency (Eq. 4), under the assumption of a

perfect market. Option 1 is then preferred over option 2 if (Eq. 5) holds.

NPV= (Eq. 6)

NPV1>NPV2 (>0) (Eq. 7)

Based on the start- and end level of contamination, remediation has different time ranges,

depending on the used crop. Total economic value is then calculated as the sum of revenues

resulting from the remediating crops, and revenues from activities after remediation, over an

infinite time range, based on market prices. However, market prices do not always correctly

reflect consumer’s willingness to pay (WTP). An activity may generate impacts that spill over to

other economic agents. These spill-overs or externalities can either be negative (metal in rest

product) or positive (CO2 abatement from green energy production). Once the stream of

economic costs and benefits is estimated, the standard NPV methodology is applied, using a

social discount rate of 4%.

1.2 Case study: Campine region (BE)

Since the economic assessment comes early in the project, we base our calculations on data from

a case study in Belgium. Cd concentrations in the region range between 0.2 and >30 mg kg-1 Cd

(Ruttens et al., 2008). pH-KCl values range between 5 and 5.5. Other trace metals (e.g. Copper

(Cu), Lead (Pb) and Zn) together with the pH and soil conductivity were more homogeneously

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distributed throughout the field. The experimental site is located in Flanders, Belgium

(51°12'41"N; 5°14'32"E) and is part of a larger complex of field experiments for

phytoremediation research (~ 20 ha) (Ruttens et al., 2008). The first SRC plantation of willow

and poplar in Lommel was planted in April 2004 by Hasselt University on a former maize field.

Total soil metal concentrations were in the range of 210-418 mg kg-1 Zn, 4.1-7.4 mg kg-1 Cd and

160-222 mg kg-1 Pb. Soil pH-KCl ranged between 4.7 and 6.0. On this field, also maize,

rapeseed, and tobacco were grown on small plots. Based on the results and experiences gained at

the first experimental field, a second SRC field was set up next to the original one by Hasselt

University, Ghent University, and the Research Institute for Nature and Forest (INBO) where, in

addition to some new commercial clones of poplar and willow, several clones of the SRC

breeding program of INBO were included. Furthermore, also energy maize and rapeseed were

sown on a 1 ha area of the second field to gain experience with the use of these energy crops for

phytoremediation purposes. All cultivars and clones were investigated for metal balances, metal

extraction, and biomass production. Table 0-1 presents an overview of biomass yields on the

experimental field (contaminated with Cd, Pb, and Zn) in the Campine region. Table 0-2 presents

an overview of Cd extraction by the studied energy crops and the resulting remediation duration.

Table 0-1 Biomass yield of energy maize, rapeseed and SRC of willow on the experimental

field in the Campine region (Ruttens, 2008; Ruttens et al., 2008; Van Slycken et al., 2011)

Rapeseed Energy maize Willow

Organs Biomass yield

(ton dm ha-1y-

1) †


(ton dm ha-1y-

1)†


(ton dm ha-1y-

1)

Seed 3 Rachis 1.8 Stem 4.8

Green Parts 2.2 Grain 8 Leaves 1.2

Bract 1.3

Stem 5.2

Leaves 3.7

Total 5.2 Total 20 Total 6 †rapeseed: 3.3 ton fresh matter (fm) seeds ha-1 y-1; energy maize: 60 ton fm ha-1 y-1

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Table 0-2 Extraction of Cd to reduce concentration in soil from 5 to 2 mg kg-1 for energy

maize, rapeseed, and willow, based on Vangronsveld et al. (2009)

Biomass

(ton dm ha-1)

Cd

(mg kg-1 dm)

Cd removal

(kg ha-1 y-1)

Clean up time

(y)

Maize 20 3 0.06 188

Rapeseed 5.2 6 0.03 361

Willow-twigs 4.8 24 0.12 195

Willow-leaves 1.2 60 0.07

Willow-total 6 0.19 120

Source: Vangronsveld et al. (2009)

2. Private costs and benefits

The value of land before remediation is equal to the income generated on that land before

remediation. During remediation, there will be costs (or revenues). The value of the land after

remediation is equal to the income that can be generated on the land after remediation. In the

CBA, we compare the rise in income (after – before remediation) with the cost of remediation.

Since we have no data from the project yet, we will take data from the Campine case study.

Before remediation, not all agricultural activities are allowed, on average farmers generate an

income of € 960 ha-1 y-1 on the land. After remediation, more activities are allowed, and more in

particular, activities that generate a higher income, twice as much (€ 1,747 ha-1 y-1). However,

during remediation there might be costs (i.e. remediation crops might generate private revenues

that are lower than the current “reference” revenue). The costs and revenues of these remediation

crops are summed up in the next tables.

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Table 0-3 PRIVATE variable costs and revenues for energy maize per hectare per year

Variable costs (€ ha-1y-1) Variable costs (cont.)

Preparation Harvest

Ploughing 60 Silage 300

Harrowing 40 Transport 0

Planting Revenues (€ ha-1)

Plant material 170 Total plant or grain 1,800

Planting 70 Single payment 450

Maintenance

Fertilizer 150

Herbicides 100

Fert. and herb. application 100

Source: personal communication with farmers in the region, Aegten, and external firms (2009)

Table 0-3 represents all costs and revenues of energy maize per ha per year. The biomass

production of energy maize is estimated at 60 ton fm ha-1. According to local farmers, this could

be a maximum because of restricted fertilizer standards (Aegten153, personal communication,

March 2009). When energy maize is sold on the field, the buyer pays harvest and transport (> 20

km). The price of (energy) maize depends on fuel and chemical fertilizer prices. When these

prices rise, the price of maize rises too. The price of silage maize depends on the price of maize

sold for the grain. We used a price of € 30 ton-1 fm. The distance from the Campine region to the

closest digestion installation is 20 km, resulting in no extra transport costs, based on (Eq. 8), with

T = transport cost per ton fm, and Dis = distance (km).

T= (Dis/5) – 4 (Eq. 8)

153

Local fodder production and merchandising.

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Table 0-4 PRIVATE variable costs and revenues for rapeseed per ha

Variable costs (€ ha-1y-1) Variable costs (cont.)

Preparation Stalk control 50

Ploughing 0 Harvest

Harrowing 0 Seeds 150

Planting Transport 70

Plant material 60 Revenues (€ ha-1)

Planting 65 Seeds 692

Maintenance Straw 111

Fertilizer 180 Single payment 450

Herbicides 80 Cake for fodder 338

Fert. and herb. application 50

Source: Suenens (2007), Aegten (personal communication, March 2009).

Table 0-4 gives an overview of agricultural costs and revenues for rapeseed. Rapeseed is only

grown once every three years. In the two intermediate years energy maize will be grown. The

average fresh rapeseed yield (20 farmers) in the Campine region is 3,330 kg ha-1. Also, 2.22 ton

straw is produced. The average of market- and contract prices for rapeseed in 2006 was € 208

ton-1. Soy and rapeseed are important sources for the production of oil for food and biodiesel.

Prices are therefore world market prices. Straw is sold for € 50 per ton. The distance from the

Campine region to the closest biodiesel producer is about 120 km, leading to a transport cost of €

70 per ha (Eq. 8).

In theory, farmers have several options for the seeds. They can sell rapeseeds as such (to a

biodiesel producer), or they can press the seeds and use the oil for personal car use or tractor use.

When rapeseed is pressed on the farm, the rest product, cake (2.16 ton) is sold as fodder at €

156.25 ton-1. Additional costs for rapeseed pressing (and use on the farm for tractor or personal

vehicles) are represented in Table 0-5. When rapeseed is sold to a conversion installation, there is

no private income from the cake for the farmer.

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Table 0-5 Additional cost on farm (€ ha-1 y-1) when rapeseed is pressed to PPO on the farm

Pressing costs Rebuilding tractor Rebuilding vehicle

Cap. cost press (5 y) 8,000 Cost rebuild engine 2,500 Cost rebuild

engine

2,500

Cap. cost storage tank 500 Deprec. period 10 Deprec. period 10

Cap. cost filter 4,700 Hours tractor y-1 750 Km total period 200,000

Cap. cost press (50 ton

y-1, 389 l PPO ton-1)

2,800 Oil use (l h-1) 5 Oil use (l km-1) 0.08

Total oil use 37,500 Total oil use 16,000

Cost l-1 PPO y-1 0.082 Cost l-1 PPO y-1 0.067 Cost l-1 PPO y-1 0.15625

l PPO ha-1 1,295 l PPO ha-1 1,295 l PPO ha-1 1,295

Pressing cost

(€ ha-1)

106.56 Rebuilding cost

(€ ha-1)

86.33 Rebuilding cost (€

ha-1)

202.34

Source: Flemish Government, policy domain Agriculture and Fisheries (2005)

Table 0-6 gives an overview of variable costs and revenues for SRC of willow. Most work will

be done by an external firm. At the experimental field, the average yearly harvest of stems and

leaves is respectively 4.8 and 1.2 ton dry matter per hectare. On the one hand, wood prices

depend on wood quality (N. Vanaken154, personal communication, February 2009). SRC of

willow has characteristics that make it very attractive for (co-)combustion installations: low ash

content, low nitrogen content, clean (no iron, sand, stones). This will most likely lead to an

interesting price. On the other hand, wood prices depend on the legal status of the wood (N.

Vanaken, personal communication, February 2009). Finally, prices also depend on the market.

We determine the price for wood at € 50 ton-1 dm. The distance from the Campine region to the

closest combustion installation is 20 km, leading to no extra transport cost.

154

Public Waste Agency Flanders (OVAM).

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Table 0-6 PRIVATE variable costs and revenues for SRC of willow per hectare (years

indicated between brackets)

Variable costs (€ ha-1) Variable costs (cont.)

Preparation (€ ha-1 y-1) End of life cycle (€ ha-1)

Ploughing 67 Stool removal 1,500

Harrowing 75 Harvest and chip 800

Herbicides (3x) + application 240

Fertilizer + application 90 Revenues (€ ha-1)

Plant material 1,800 Stem (per year, every 3 years) 240

Planting 450 Single payment 450

Harvest (€ ha-1 every 3 years)

Harvest and chip 800

Herbicides 240

Transport 0

Source: external firm (personal communication, 2009), and Meiresonne (2006)

These tables are the basis of the income calculation. For calculations on the income of alternative

energy crops, we used the adapted gross income (AGI) as a measure.

ADAPTED GROSS INCOME (AGI)

= REVENUE (MARKETABLE PRODUCTS (MAIN AND REST) + ANIMALS + OTHER + SUBSIDIES) – COST

(THIRD PARTY LABOR + EQUIPMENT + HERBICIDES AND PESTICIDES + FERTILIZER + SEED AND

PLANTING MATERIAL + ANIMAL RELATED + CROP RELATED + FUEL)

Rapeseed (AGI = € 549 ha-1 y-1) is grown in rotation with energy maize (AGI = € 1,260 ha-1 y-1),

resulting in an AGI between € 1,023 and € 1,354 ha-1 y-1. An average AGI for SRC of willow (€

111 ha-1 y-1) is obtained by recalculating the NPV over 22 years to an annuity, i.e. a yearly

constant cash flow (CF) which, after discounting, would again lead to the same NPV. The prices

that farmers get for their crops is independent of the use of the crops. This results in final AGI’s

(€ per hectare) and prices per ton fresh matter for the remediating crops as presented in Table 0-7.

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Table 0-7 Yearly AGI (€ ha-1) and price (€ ton-1 fresh matter) of remediation crops for

different conversion options

Energy

maize

Rapeseed-

PPO-pers

use

Rapeseed -

PPO-

tractor

Rapeseed -

Biodiesel

SRC-

electr.

SRC-

heat

SRC-

CHP

AGI 1,260 1,354 1,195 1,023 111 111 111

price 30 477† 298† 208 28.5 28.5 28.5

AGI=adapted gross income; †3.33 ton seeds are converted into 1,295 liter oil. Value of PPO for

personal use is € 1.226 l-1. Value of PPO for tractor is € 0.767 l-1

On the one hand, based on a private economic analysis (Table 0-7), one would argue for energy

maize or rapeseed as an alternative energy crop on contaminated land. Both crops result in the

lowest impact on farmer income. Thewys et al. (2010a) provide an extended economic analysis

on the replacement of conventional fodder maize by energy maize on metal enriched land. As can

be seen in Table 0-2, the choice for energy maize or rapeseed would result in long remediation

durations. One can therefore no longer speak of soil remediation, but instead of sustainable land

management with risk containment as the main purpose. On the other hand, growing SRC of

willow results in a considerable reduction in remediation duration, but the crop does not have the

economic advantage of energy maize and rapeseed, mainly due to the high harvest costs of this

unfamiliar crop. However, as was already indicated in Witters et al. (2009), to make

economically efficient decisions on crop choice, these private costs and benefits should be

complemented with other costs and benefits, one of which is the renewable energy production

potential, which will be studied in further detail in the next paragraph.

3. Biomass for energy

Using the resulting biomass for energy may contribute to the reduction of global carbon dioxide

(CO2) emissions. Biomass can replace fossil fuels for the supply of heat, electricity and transport

fuel, and can also serve as a feedstock for material production (Dornburg and Faaij, 2005). As

mentioned by Firbank (2008), one factor that drives the growth of alternative crops for energy is

the fact that they deliver an environmental benefit by reducing greenhouse gas (GHG) emissions.

To find out whether CO2 abatement by converting these crops to energy is positive, we

performed a Life Cycle Analysis (LCA). LCA attempts to cover all physical exchanges of a

product with its surroundings, ranging from inputs of auxiliary materials and energy consumption

through outputs of emissions, waste and usable energy (Hanegraaf et al., 1998; Skovgaard,

2008). Figure 0-1 gives an overview of the different steps in determining the potential benefit of

CO2 abatement when using the harvested biomass after remediation for energy purposes.

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1 EI = direct + indirect energy input for crop establishment, incl. transport to conversion installation

2 EO = total energy output (corrected for conversion efficiencies and process use)

3 E’post in UC = energy input for the economically most viable end-use of biomass and rest product

4 E’post out UC = energy output for the economically most viable end-use of biomass and rest product

Figure 0-1 Biomass conversion routes for remediation crops with indication of CO2

abatement locations

In order to keep the LCA task manageable, a general rule is to focus on obtaining good data on

those activities considered most important for the final LCA results (Hanegraaf et al., 1998;

Skovgaard, 2008). Within the scope of this study it is not a priority to study an entire life cycle, it

is therefore more effective to set clear, narrow borders than to set vague borders and include

some energy aspects and some not.

3.1 Assumptions

It is often difficult to describe the reference case for land use (Schlamadinger et al., 1997). The

reference situation in our case study (Campine region) is the “no activity allowed on the

contaminated land” situation. The studied impact category in our analysis will be limited to the

Global Warming Potential (GWP) of CO2. This paper does not include a life cycle analysis of the

manufacture of the conversion installations, nor the effects of decentralized electricity production

on general electricity distribution, for several reasons. First, the main focus of this paper is the

1 E n e r g y m a i z e R a p e s e e d W i l l o w

H e a t +

E l e c t r i c i t y

D i g e s t a t e

A n a e r o b i c d i g e s t i o n

C o l d p r e s s i n g

P r e s s i n g + e s t e r i f i c a t i o n

( C o - ) c o m b u s t i o n

+

P P O B i o d i e s e l

C a k e

+

C a k e +

G l y c e r i n e

+

A s h e s

E l e c t r i c i t y H e a t H + E 2

+

4

3

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evaluation of energy crops (after phytoremediation) and not the technical specifications of the

installations. Second, we start from an existing installation, we are not considering a new

installation for the conversion of contaminated biomass to energy. And third, we are convinced

that specifically designed tools are much better suited for this, see for example the tools

developed within the framework of Task 38 of the International Energy Agency on Greenhouse

Gas Balances of Biomass and Bioenergy systems (http://www.ieabioenergy-task38.org). We are

also aware that the combustion technology needs to be developed and adapted properly to deal

with other biomass such as dried digestate as it may lead to excessive corrosion in boiler tubes,

excessive slagging and fouling, and higher emissions of NOx and particulate matter

(www.ieabcc.nl). While this study takes into account all transportation steps (emissions from fuel

consumption) of biomass and rest products, it does not take into account the manufacture of the

vehicles used for transportation or the manufacture of the vehicles that will use the biofuel. We

also do not take into account the energy used for maintenance of idle land (i.e. the reference

situation), as opposed to Kaltschmitt et al. (1997). The approach used in this study and suggested

by Schlamadinger et al. (1997) compares greenhouse gas emissions that arise over the life cycle

of each potential technology with those that would have arisen in the base case (fossil fuel),

allowing for the reduction in emissions to be calculated.

3.2 Fossil energy input for biomass production

Direct energy use of phytoremediation refers to the fossil fuel consumed within the borders of the

farm. Indirect energy use of phytoremediation refers to fuel burned in other sectors that

manufacture the materials needed at the farm. Following the example of Refsgaard et al. (2002),

we set the boundaries one step back from the farming process (Table 0-8). Summing up direct

and indirect energy input results in total fossil energy inputs.

Table 0-8 Direct and indirect energy input for biomass production

Direct Indirect

-Diesel fuel use machines (plowing, disking,

planting, cultivation, application of

fertilizers, herbicides, lime and manure, and

harvest), corrected for extraction and

distribution

-Production and transport fertilizer, lime, and

pesticides (herbicides, insecticides, and

fungicides)

-Production of seeds

-Manufacturing, transport and reparation machines

-Use of lubricants for machines

-Irrigation

-Ensiling

-Drying

-Transport crops to conversion installation

http://www.ieabioenergy-task38.org/

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We always consider a one-way transport distance of 30 km, except for the distance between a

digester and a farm (20 km), and the distance between a biodiesel installation and a farm (120

km). When rapeseed is mechanically pressed to PPO, this will be used on the farm or in personal

vehicles (0 km). When rapeseed is converted into biodiesel, the whole processing takes place at

the biodiesel production installation. There is thus never a transport of PPO, only of rapeseed

(and straw).

3.3 From biomass to gross energy

Since we have no data yet on which crops could potentially be grown, we restricted our analysis

to 6 biomass-conversion options, based on data from a Belgian case study. However, the

methodological approach could easily be extended to other case studies. Table 0-9 provides an

overview of all crop conversion options analysed in the Campine case study. The symbols used

in the formulae can be found in Table 0-10, values can be found in Table 0-11.

Table 0-9 Different energy conversion options for biomass after remediation with indication

of the fossil substitute

Option Net energy Fossil substitute

Willow co-combustion Electricity combination of coal†

Willow co-combustion Heat cokes‡

Willow combustion CHP-steam turbine

(elec.+heat)

separate heat and elec.

production

Energy maize digestion CHP- gas engine

(elec.+heat)

separate heat and elec.

production

Rapeseed-pressing PPO fossil diesel

Rapeseed-

pressing+transesterif.

Biodiesel fossil diesel

†at a large power plant in Belgium. The installation considered in this study is close to the

Campine region; ‡at a Zinc smelter in the Campine region

Energy maize is digested anaerobically, a conversion process where organic matter of biomass is

converted into methane in four phases by bacteria in the absence of oxygen. The end products of

the digestion process are biogas and digestate. Due to its high energy content, biogas can be used

in engines and machines to replace natural gas, be used as a transport fuel or even be injected in

the natural gas distribution network (Verstraete, 1981; Ramage and Scurlock, 1996). We opted

for the first choice, burning the gas in a gas engine for the production of electricity with heat

recovery in a combined heat and power (CHP) system. Electric and thermal efficiency of a CHP

are lower than for the separate production of electricity and heat but the simultaneous production

of electricity and heat from one input renders a higher overall energetic efficiency.

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Table 0-10 Symbols used in (Eq. 9)-(Eq. 17)

Symbol Explanation Unit

BPW potential biomass production of willow Ton dm ha-1 y-1

CALW calorific value of willow GJ ton-1 dm

α loss of biomass/energy due to drying in open air/conditioned

drying

%

BPEM potential biomass production of energy maize Ton fm ha-1 y-1

GEM biogas yield of energy maize m³ gas ton-1 fm

EVBG energy value of biogas MJ m-³

BPRS potential biomass production of rapeseed Ton fm ha-1 y-1

GPPO efficiency of mechanical rapeseed pressing to PPO Ton oil ton-1

fm

DPPO density of PPO Ton l-1

EVPPO energy value of PPO MJ l-1

GBD efficiency of rapeseed conversion to biodiesel Ton fuel ton-1

fm

DBD density of biodiesel Ton l-1

EVBD energy value of biodiesel MJ l-1

EI total primary energy input MJ ha-1

EO total energy output MJ ha-1

EIpred direct energy input crop establishment, incl. transport crop to

installation

MJ ha-1

EIprei indirect energy input during establishment of the crop MJ ha-1

GEC gross energy content MJ ha-1

η(th),η(el),η(m) conversion efficiency (resp. thermal, electric, and mechanical) %

β(th),β(el),β(f) fossil energy use during conversion (resp. thermal, electric and

diesel fuel)

%

Epost output (Epost out) - input (Epost in) of energy for secondary use rest

product

MJ ha-1

The gross energy content of energy maize (per ha) after digestion (GECEM) is calculated in (Eq.

9):

GECEM = BPEM . GEM . EVBG (Eq. 9)

Mechanical pressing of rapeseed can be warm or cold. The resulting products are pure plant oil

(PPO), and rapeseed cake (cold) or scrap (warm). This cake is a marketable co-product, used

mainly as cattle feed. Warm pressing renders a higher percentage of available oil (32-42 m%)

than cold pressing (28-35 m%). On a large scale (e.g. prior to biodiesel production), chemical

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pressing renders 42 m% of PPO. Further transesterification of the PPO results in biodiesel.

Biodiesel can be burned in a regular diesel engine as such to replace fossil diesel, whereas for

the combustion of PPO, some adjustments to the engine are necessary. After transesterification

of PPO, crude glycerine is obtained (Eq. 10) (Van de Plas, 2007).

1 ton PPO + 0.1 ton methanol 1 ton biodiesel + 0.1 ton glycerine (Eq. 10)

The gross energy content of PPO and biodiesel per hectare (GECPPO and GECBD) are calculated

in (Eq. 11) and (Eq. 12) respectively.

GECPPO = BPRS . GPPO . DPPO . EVPPO (Eq. 11)

GECBD = BPRS . GBD . DBD . EVBD (Eq. 12)

For SRC of willow, we consider three options. First, co-combustion of biomass with coal has

already been widely applied (Goovaerts et al., 2009) and its economic potential has been

indicated (Hughes, 2000). Willow from phytoremediation could be co-combusted in a power

plant replacing coal (Electrabel). Currently, the installation of Electrabel in Ruien (540 MWe)

indirectly co-combusts pulverised coal with woodchips from recycled fresh wood and hard and

soft board (www.ieabcc.nl). We consider another installation of Electrabel (Langerlo) as this one

has a deNOx and deSOx installation. The maximum yearly potential for co-combustion would be

200,000 ton (5%). Nussbaumer and Oser (2004) conclude that it can be assumed that the energy

needed for the pre-treatment of wood chips is included in the efficiency of power production.

Theunis et al. (2003) also mention that coal cannot be used as such in a coal power plant but has

to undergo some pre-treatment which results in coal powder. The same pre-treatment is needed

for the wood chips replacing coal. Second, willow could be used for heating purposes to replace

cokes in the zinc smelter of Nyrstar (former Umicore). Since the startup of the copper smelter in

1997, first as part of Umicore and from 2007 on as an independent company, secondary sources

are co-combusted, according to the license. To result in the same heat output, relatively more

biomass has to be burned than coal due to the lower heating value of the former. Since this

requires additional storage, handling, and transport, there is a maximum amount of biomass that

can be co-fired for the installation to be still economically viable (Sami et al., 2001; Baxter,

2005; Eriksson, 2007). Third, we consider the (co-) combustion of willow in a biomass based

combustion installation with electricity and heat production in a CHP system. This replaces the

separate production of heat (natural gas) and electricity (average fossil mix).

The gross energy content of SRC is based on its calorific value, which is the amount of energy

present in the wood and liberated when burned (thus after drying). The gross energy content of

willow (after drying) per hectare (GECW) is calculated in (Eq. 13).

GECW = BPW . CALW . (1-α) (Eq. 13)

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Table 0-11 Base case values used in (Eq. 9)-(Eq. 17)

Symbol Base case

value

Unit

(Eq. 9)-(Eq. 13)

BPW 6 ton dm ha-1 y-1

CALW 19.92‡ GJ ton-1 dm

α 0 %

BPEM 60† ton fm ha-1 y-1

GEM 190§ m³ gas ton-1 fm

EVBG 19.11¶ MJ m-³ gas

BPRS 3.3† ton fm ha-1 y-1

GPPO 35%# ton oil ton-1 fm

DPPO 0.90†† ton l-1

EVPPO 34.11††‡‡ MJ l-1

GBD 42%# ton biodiesel ton-1 fm

DBD 0.88‡‡ ton l-1

EVBD 33.18‡‡ MJ l-1

(Eq. 14)-(Eq. 17)§§

Energy value diesel 35.9 MJ l-1 diesel

Extraction and distribution diesel 5 MJ l-1 diesel

Lubricants 3.6 MJ l-1 diesel

Energy use transport 1.3 MJ ton-1 fm km-1

Electr. use for separating digestate (11 dm% to 30

dm%)

27-36 MJ m-³ input

Heat use for drying digestate (30 dm% to 85

dm%)

2.37 GJ ton-1 separated

digestate

Energy value coal/cokes 29 GJ ton-1 cokes †Table 0-1; ‡Vande Walle (2007); §Thewys et al. (2010a, b); ¶53.25% CH4, Lower Heating Value

LHV(CH4) = 35.9 MJ m-³; #GAVE (2005); ††www.hanze.nl and www.wervel.be; ‡‡www.emis.vito.be, RE Directive (2009/28/EG); §§Borjesson (1996), Dalgaard et al. (2001),

Lemmens et al. (2007), and www.emis.vito.be

3.4 Effect of contaminants on energy production potential

3.4.1 General

For PPO there are no indications that the ash content after burning could pose any problems. Ash

content of renewable fuels commonly lies below 1 m% and most commonly below 0.1 m%.

When biomass with a high (>2%) fatty acid content is combusted, this causes corrosion.

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However, fatty acid content in PPO is smaller than 1%. The viscosity of PPO lies above that of

diesel. Therefore, for PPO to be used in a diesel engine, the oil should be preheated prior to use,

or mixed with diesel, or converted into biodiesel through esterification (Goovaerts et al., 2009).

Mench et al. (2010) point out correctly that in order to minimise trace element emissions of

vehicles running on biodiesel or PPO from phytoremediation crops, plants could be selected

based on low trace element contents in their seeds.

Obernberger has done extensive research on the combustion of biomass (e.g. Obernberger et al.,

1997; Obernberger, 1998). This resulted in maximum values of certain elements in biomass and

renewable energy resources above which emission threshold values might be exceeded and

technical problems might occur.

Information, data and studies relating to the potential influence of metal concentrations in

biomass on the digestion process are also scarce. Metals have a proven effect on the enzymes

responsible for the break-down of biomass particles. Whether they stimulate or inhibit biogas

production depends on total metal concentration, the chemical form of the metals, and process

related aspects (Chen, Cheng and Creamer, 2008). Pahl et al. (2008) found in their experiment

with co-digestion of mechanically biologically treated municipal waste containing metals and

sewage sludge evidence of the accumulation of metals in the digester. According to Marchaim

(1992), certain metals (not specified) can be toxic to anaerobic organisms, even at low

concentrations. The metal ions kill organisms by inactivating functional groups of their enzymes

and thus inhibit digestion. Wong and Cheung (1995) conducted experiments on digestion of

metal contaminated sewage sludge and concluded that presence of certain metals always tends to

reduce biogas yield (toxicity Cr > Ni > Cu > Zn). In contrast, studies on water hyacinth

(Eichhornia crassipes), channel grass (Vallisneria spiralis) and water chestnut (Trapa

bispinnosa) used as phytoremediating plants in industrial effluents, demonstrated that the slurry

of these plants produces significantly more biogas than the slurry of control plants grown in

unpolluted water (Singhal and Rai, 2003; Verma et al., 2007). These experiments indicate an

effect of metals on the digestion process, but they do not allow to come to an unambiguous

conclusion concerning biogas production from polluted energy maize.

3.4.2 Case study

We find no data on the effect of metals in biomass on the biodiesel production process, although

the idea of using the remediating crops for energy purposes is gaining ground (Shi and Cai,

2009). Therefore, no modifications are necessary to the installation. Since we assume that all

metals end up in the cake, no marginal modifications are necessary to the engine for burning PPO

or biodiesel.

Concerning the effect of metals on the combustion process, we made the comparison with the

commonly combusted coal, which also contains metals and decided that metals in biomass will

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have no marginal effect on the combustion process and on the technical efficiency of the

installation.

A subset of each sample energy maize plant from the trial field (total plant, stem, leaves, bract,

rachis, and grain) was transported to Organic Waste Systems (OWS, Ghent, Belgium) to

determine its biogas production potential in a batch test. In order to investigate the difference in

biogas production potential of maize grown on contaminated soil versus maize grown on

uncontaminated soil, samples were compared with maize originating from an uncontaminated

reference site of OWS. The small scale batch test (14 days) showed no significant difference in

biogas production potential between maize grown on contaminated (215 ± 23 Nm3 ton-1) and

uncontaminated (194 ± 4 Nm3 ton-1) soils. Nevertheless, further confirmation of these findings in

a continuum test over a longer period of time was necessary and can be found in Van Slycken et

al. (2011). Therefore, Thewys et al. (2010a) decided that no modifications to the biogas

installation are necessary. Moreover, because all metals end up in the digestate, no modifications

are needed to the CHP engine.

Based on the above, we assume for all crops that metals have no marginal effect on the energy

conversion (technical) efficiency. Moreover, no metals end up in the energy carrier, but will be

concentrated in the rest product: in the ashes, in the digestate, and in the cake. The marginal

impact (as compared to uncontaminated rest products) of the contamination in these rest products

on energy consumption to prepare the rest products for secondary use or disposal will be handled

later since a different end use might have to be found for the rest product.

3.5 From gross energy content to net thermal, electric, and mechanical energy

The electric efficiency of the combustion of woody biomass in a coal power plant (37%) is

consistent with Theunis et al. (2003), and adjusted as in Baxter (2005). Co-firing power plants

have better electric efficiency compared to 100% biomass based power plants, but compared to

coal there is a 0-10% efficiency loss in biomass conversion, due to use of non-preheated air

(which could be avoided in a permanent installation), energy use for preparation and handling of

the biomass, and a higher moisture content of the biomass (Baxter, 2005). The second option is

combusting willow for heating purposes to replace cokes. When 7-10% of biomass is co-fired,

there is a drop in overall boiler efficiency compared to coal-fired boilers. This reduction is

however minimal, 0.3-1.0 points of the 85-90% thermal efficiency (Hughes, 2000). As thermal

efficiency for combusting woody biomass we use 78% (CHP reference Decision, 2006). Finally,

wood could also be combusted with other biomass in a biomass (waste) incineration plant for the

generation of heat and electricity using a steam turbine based CHP. Examples have been studied

by the International Energy Agency for Biomass Combustion and Co-firing (IEABCC, 2004) in

Denmark and Austria. Steam turbines have a low electric efficiency (Cogen Vlaanderen vzw,

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2006). Thermal and electric efficiency (69% and 16%) of this system are based on Vande Walle

et al. (2007).

The produced gas resulting from digesting energy maize is burned in a gas engine based CHP.

This replaces the separate production of heat and electricity with fossil fuels. The thermal and

electric efficiency of a gas engine are 45% and 40% respectively (Table 0-12).

Table 0-12 Relevant conversion efficiencies to be applied on the GEC of the different

options (η=efficiency, β=use, el=electricity, th=thermal, f=fuel)

Conversion technology Net energy η(th) η(el) β(th) † β(el) † β(f)

Co-combustion Electricity 37%¶ # 4%#

Co-combustion Heat 78-80%¶ #

Combustion CHP (steam

turbine)

55-69%# †† 16%# †† 4%‡ 3%‡

Digestion CHP (gas engine) 45%‡‡ 40%‡‡ 30%§§ 7.5%§

PPO (mech pressing) PPO 2%¶¶

Biodiesel

(chem+transesterif)

Biodiesel 2%¶¶ 8%¶¶

†% of CALW, % of GECEM, and % of GECRS; ‡Cidad et al. (2003); §Goossens (2007); ¶CHP Ref

Decision (2006); #Theunis et al. (2003); ††Vande Walle et al. (2007); Cogen Vlaanderen vzw

(2006); IEABCC (2004) ‡‡A. Stroobandt155, personal communication (January 2009); §§E. Meers,

personal communication (March 2007); ¶¶Gustavsson et al. (1995), Janulis (2004), and 8% is

assumed for the production of chemicals

3.6 Contamination in rest product-energetic impact

3.6.1 General

After conversion, a contaminant enriched rest product remains. The presence of contaminants has

an effect on secondary use options (Table 0-13), and this effect could be monetarily valued

through (i) the marginal impact on the secondary use of the rest product (due to restricted options

compared to the uncontaminated ″reference″ option), but also through (ii) the marginal impact on

final CO2 abatement. In §0 we calculate (i) by comparing the allowed use of the contaminated

rest product with the allowed use of the uncontaminated ″reference" option. In this part (§0) we

include (ii): CO2 abatement of the different energy crops is immediately corrected for the

marginal impact of contaminants in the rest product, i.e. we started with calculations for

″reference″ uncontaminated biomass, and made changes necessary due to the contamination in

the rest product.

155

Cogen Flanders for the promotion of CHP installations in Flanders.

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3.6.2 Case study

Uncontaminated digestate is a good alternative for chemical fertilizer or could be used as soil

improving material. Due to N, P, and K threshold values, not all digestate (47 ton) resulting from

one hectare of energy maize can be applied on that same hectare. Approximately 33 ton

uncontaminated digestate could be applied per hectare. Only 13.77 ton uncontaminated (11 dm%)

digestate is separated and dried resulting in 1.78 ton (85 dm%) for combustion. In the

contaminated best option, 44.4 ton digestate (11 dm%) should be separated and dried resulting in

5.76 ton (85 dm%) for combustion. This is because besides the restrictions on N, P, and K, there

are also restrictions regarding the maximum allowed trace element concentrations in the digestate

if it is to be used as fertilizer or soil improving material. Combustion of digestate results in 0.076

ton ashes that will be landfilled.

1 ha rapeseed (3.3 ton) generates resp. 1.17 and 1.40 ton oil (in PPO and biodiesel scenario), and

resp. 2.16 and 1.93 ton cake. The oil could subsequently be converted to biodiesel through

transesterification (100%): 1.40 ton rapeseed oil + 0.14 ton methanol 1.40 ton biodiesel + 0.14

ton glycerine. After comparing legislation and concentrations of metals found in rapeseed cake,

we decided that this product can still be used as fodder. Rapeseed cake does not need to undergo

any energy consuming pre-treatment before use as fodder. Ashes can be used as granulates

according to current legislation. When using uncontaminated woody biomass, no pre-treatment is

necessary. When the woody biomass is contaminated, the ashes need to be landfilled.

Table 0-13 End use of the rest product (ton ha-1)†

Rest product (ton) Eco most viable option-

uncontaminated (ton)

Eco most viable option-

contaminated (ton)

Digestate (47.2) Fertilizer (33.43)+Combustion (13.77) Fertilizer (2.80)+ Combustion

(44.40)

Cake PPO (2.16) Fodder (2.16) Fodder (2.16)

Cake Biodiesel

(1.93)

Fodder (1.93) Fodder (1.93)

Glycerine Digestion (0.14) Digestion (0.14)

Ashes (0.0768) Granulates (0.0768) Landfill (0.0768)

3.7 Overview

3.7.1 General

Besides generating energy output (Epostout), the rest product also needs energy input prior to

secondary use (Epostin). This energy input and –output are different from uncontaminated biomass.

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For all rest products, Epostin also includes transport (Table 0-14). We have not included the energy

cost of applying digestate (0.6 l diesel ton-1) since we assume that this is compensated by

applying less chemical fertilizer (2 l ha-1) (Cidad et al., 2003). Moreover, we did not take into

account the energy cost of upgrading the ashes to granulates and will also not take into account

the energy cost of the replaced building materials by these granulates (Table 0-14).

Table 0-14 Overview of marginal energy in- and output for secondary use of rest products

from uncontaminated biomass (T=transport)

Rest

product

Reference

option

Epost in Epost out

Digestate

(11 dm%)

Fertilizer +

Combustion

(heat)

Separation (30 dm%) and

drying (85 dm%): elec. and

heat

T(digestate to field)

T(digestate to combustion

install)

T(ashes to landfill)

Energy cost chemical fertilizer

(incl. T)

Combustion value digestate

(heat)

Cake Fodder T(fodder to farm) Energy cost roughage production

(incl. T to farm)

Glycerine Digestion T(glycerine to digester) Digestion

Ashes Granulates T(ashes to landfill) /

EI = EIpred + EIprei (Eq. 14)

EO = GEC . η(th) . (1-β(th)) + GEC . η(el) . (1-β(el)) (Eq. 15)

EO = GEC . (1-β(f) - β(el)) (Eq. 16)

Epost= Epostout- Epostin (Eq. 17)

(Eq. 14) calculates the total energy input for willow, energy maize and rapeseed. (Eq. 15)

represents the energy output used for energy maize and willow, while (Eq. 16) is used for

rapeseed. (Eq. 17) calculates the net energy due to secondary use of the rest product. The total

primary energy input only contains processes where actual fossil energy is used. Renewable

energy uses or losses, such as during natural drying for willow (α) or during conversion to heat

and electricity (η and β), will not be considered as energy inputs. They are considered losses of

energy output and as such will be distracted from the output. This is different from the approach

used by Vande Walle et al. (2007) where the use of electricity and heat during conversion were

considered as energy input.

We calculated the net energy production (NE) per hectare per year. Based on NE (EO + Epost –

EI), we calculated the net avoided CO2 emission compared to the case where the same amount of

energy (heat, electricity or movement) would have been based on fossil fuels, with energy uses

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and combustion values, and fossil fuel emission coefficients in Table 0-11 and Table 0-15

respectively.

Table 0-15 Reference fossil fuel efficiencies and emissions

Natural gas Cokes Coal Average Lubricants Diesel

g CO2 kWh-1

100% 201.96† 385.2† 263.88† 266.76†

Engine

(η(m))

659.7

(40%)‡

666.9

(40%)‡

Heat 224.4

(90%)§

481.5 (80%)§ 296.4

(89%)§

Electricity 116-398†† 508-

897††

413.18¶

CHP (η(el)) 1,540.8

(25%)#

†IPCC (2007); ‡Cidad et al. (2003); §CHP reference Decision (2006); ¶MIRA (2008); #Cogen

Vlaanderen vzw (2006); ††Born (n.d.); Envirochem (2005)

3.7.2 Case study

Energy maize

Energy maize is digested and the resulting biogas is combusted in a gas engine in a CHP system,

resulting in heat and electricity (Table 3-10). The digestate is partly used as fertilizer, partly

combusted, according to Flemish and European legislation.

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Table 3-10 Energy costs for crop growth and net energy gain after conversion of energy

maize (GJ per hectare per year)

Energy (GJ ha1 yr-1) Source

Crop growth 6.77 (Cidad et al., 2003; Dalgaard, 2001) †

Transport energy maize to

digester

1.56 (Borjesson, 1996)

Indirect energy 5.04 (Cidad et al., 2003)

EI 13.37

GECEM 217.81 ‡

Net electricity 80.59

Net heat 68.61

EO 149.20 (Cidad et al., 2003; Goossens, 2007)

Epostin 40.55 §

Epostout 53.01 ¶

Epost 12.46

NE 148.29 †152 l diesel ha-1; ‡60 ton fm ha-1 y-1, 190 m³ gas ton-1 fm, 19.11 MJ m-3 gas ; §energy for

separation is 0.036 GJ ton-1 digestate (11 dm%), energy for drying is 0.87 GJ ton-1 digestate (11

dm%); ¶55.53 GJ ton-1 N (incl. transport), 33.43 ton digestate (11 dm%) replaces 170 kg N,

combustion value digestate (11 dm%) is 1.18 GJ ton-1

Because of metals in the rest product, Epost in for contaminated digestate is 40.55 GJ ha-1. Epost out is

53.01 GJ ha-1. This results in Epost = 12.46 GJ ha-1, resulting in a net positive impact of metals on

energy production (0.44 GJ ha-1) because the presence of metals forces us to use the digestate for

other purposes which are more energy efficient than its use in the reference situation.

Willow

We use a mean calorific value for willow of 19.92 GJ ton-1 dm (Vande Walle et al., 2007). Table

3-11 gives an overview of total average energy costs for willow per hectare per year. For willow,

the largest contributor is the indirect machinery cost, followed by planting material preparation

and final stool removal.

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Table 3-11 Energy costs for crop growth and net energy gain after conversion of Short

Rotation Coppice (SRC) of willow (GJ per hectare per year)

Energy (GJ ha-1 yr-1) Source

Crop growth 8.41† (Cidad et al., 2003; Dalgaard,

2001)

Transport SRC to co-

combustion

0.33 (Borjesson, 1996)

Indirect energy 2.61 (Cidad et al., 2003)

EI 11.35

GECW 95.62‡ (Vande Walle et al., 2007)

(1) (2) (3)

Net electricity 31.55 12.43

Net heat 74.58 62.15

EO 31.55 74.58 74.58

Epostin 0.003§ 0.003§ 0.003§

Epostout 0 0 0

Epost -0.003 -0.003 -0.003

NE 20.20 63.23 63.23 †189 l diesel ha-1 y-1 is an average yearly use over 21 years (Cidad et al., 2003); ‡4.8 ton dm ha-1

y-1 (excl. leaves) after first rotation cycle (15-20 ton over 3 years); (1) electricity, (2) heat, (3)

CHP; §30 km transport distance, 76.8 kg ashes

There is no impact of metals in ashes on Epost in, and Epost out since we assume that transport

distances are the same for uncontaminated and contaminated ashes. Moreover, we did not take

into account the energy cost of replaced building materials by granulates in the uncontaminated

scenario.

Rapeseed

Rapeseed results are represented in Table 3-12. The same amount of rapeseed cake can be used as

fodder in the uncontaminated and contaminated scenario, resulting in a zero effect of metals on

the net energy production per hectare.

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Table 3-12 Energy costs for crop growth and net energy gain after conversion (1) into PPO

and (2) into biodiesel of rapeseed (GJ per hectare per year)

Energy (GJ ha-1 yr-1) Source

(1) (2)

Crop growth 3.13 3.13 (Cidad et al., 2003)

Transport rapeseed to biodiesel/PPO +

transport straw

0.06 0.58 (Borjesson, 1996)

Indirect energy 10.90 10.90 (Cidad et al., 2003)

EI 14.02 14.54

GECPPO 44.17†

GECBD 52.73†

Electricity use 0.88 1.05

Fuel use 4.22

EO‡ 43.29 47.45

Epostin§ 0 0.30

Epostout¶ 1.97 3.09

Epost 1.97 2.79

NE 31.17 35.64 †3.3 ton rapeseed ha-1 y-1; ‡we did not take into account the transport of biodiesel or PPO after

conversion; §transport of cake and glycerine after biodiesel; ¶net energy (GJ) saved per ton cake =

(46.55 GJ-19.95 GJ)/29.2 ton cake; 750 m³ gas per ton glycerine (K. Sys156, personal

communication, April 2010) resulting in 0.72 GJ electricity and 0.61 GJ heat

3.8 CO2 abatement (case study)

The yearly CO2 abatement per hectare for each option can be found in Table 3-13. Electricity

output is based on average electricity emissions, except for the co-combustion of SRC of willow

for electricity, where the use of willow replaces the use of cokes (since this is the current energy

carrier at the installation where the willow will be used). The renewable heat output takes into

account conversion efficiency. When calculating CO2 abatement, the avoided emission of fossil

fuels was corrected for boiler efficiency. Rapeseed produces biodiesel or PPO, and in both cases

the numbers in Table 3-12 represent output before conversion in an engine. This implies that to

calculate avoided CO2 emissions, we used emission efficiency of fossil diesel as such, i.e. we do

not take into account engine efficiency for biodiesel and PPO.

The emissions for electricity input are based on average electricity emissions (Table 0-15). With

regards to fossil diesel input, the number in Table 0-15 already takes into account engine

efficiency, implying that CO2 emissions of fossil diesel do not have to be corrected for engine

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Biogas-e vzw, for the promotion of digestion in Flanders

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efficiency. The extraction of fossil diesel is also taken into account, as well as the use of

lubricants. Transport and indirect energy use always assume the use of fossil diesel. During

biodiesel production, diesel fuel is used (8%) of gross biodiesel production.

The heat used for drying digestate comes from heat produced in the digester which takes into

account efficiency of the CHP engine. Therefore, to calculate avoided CO2 emissions, we correct

the emission of heat produced by cokes in the reference case with the boiler efficiency. The

calculation of CO2 emission avoidance of the part of the digestate used as a fertilizer (33.43 ton)

is based on the energy use for the production of chemical fertilizer (West and Marland, 2002) and

includes transport. The calculation of CO2 abatement by combustion of digestate for heat

production (13.77 ton) is based on a comparison with heat based cokes, taking into account boiler

efficiency.

Table 3-13 Net CO2 avoidance per hectare per year for energy maize, SRC of willow, and

rapeseed (kg CO2 ha-1 y-1) (net emissions between brackets)

CO2 (production) Energy maize SRC SRC SRC Rapeseed Rapeseed

diesel use (950) (791) (791) (791) (1,009) (1,047)

lubricant use (40) (50) (50) (50) (34) (34)

CO2 (conversion)(EO) Digestion Electr. Heat CHP PPO Biodiesel

electricity +9,249 +6,157 0 +1,427

heat +4,277 0 +9,975 +3,874

diesel

+3,273 +3,907

extraction diesel

+456 +544

electricity use

(101) (121)

fuel use

(313)

net CO2 avoided 12,536 5,317 9,135 4,460 2,584 2,936

Rest product sec use fertil + comb landfill landfill landfill fodder fodder

Epostin (5,375) (0.22) (0.22) (0.22) 0 (22)

Epostout +7,054

+146 +251

net after rest product (NE) 14,242 5,316 9,134 4,460 2,730 3,044

All phytoremediation crops offer the potential to reduce CO2 emissions, as would have been the

case if they were grown on uncontaminated soil. However, for energy maize the presence of

metals even has a positive effect on CO2 abatement. This is due to the fact that we started from

the economically most viable option in the uncontaminated reference scenario and not the

energetically best option. The effect is completely due to the rest product, where in the

uncontaminated and contaminated scenario the net CO2 avoidance are respectively (2,815-1,729)

kg CO2 and (7,054-5,375) kg CO2. The contaminated scenario needs heat to dry the digestate, but

combustion generates a lot of heat (replacing cokes), whereas in the uncontaminated scenario,

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less energy is necessary, since most of the digestate is applied on the field, but the avoided energy

for chemical fertilizer results in less CO2 avoidance (produced with cokes, gas, and electricity).

Considering the net energy potential before the rest product is handled, the digestion of energy

maize offers the best potential. SRC of willow to replace coke-based heat (Zn smelter) comes

second. Alternatively, SRC of willow in a biomass combustion installation and the combined

production of heat and electricity comes only after the separate production of electricity from

willow, since in the latter case willow replaces cokes, and in the former it replaces average

electricity and average heat. PPO and biodiesel score rather low on their CO2 abatement

potential, partly because of the need of fossil diesel for the production of fertilizer for production

of rapeseed.

When growing crops for energy production on land, while gradually remediating the soil, a

policy suggesting government intervention based on CO2 abatement might prove necessary to

improve economic efficiency. This is only allowed because the external benefit of CO2 abatement

is not included correctly in the price of biomass and as such not yet taken into account in

economic optimization.

Table 3-14 shows the impact of internalization of CO2 on original biomass prices (€ ton-1 fm) and

on original AGI (€ ha-1). If the valuation of CO2 is based on the marginal abatement cost (MAC)

(€ 20 ton-1 CO2), then for willow this would mean that the current AGI would double to triple.

The impact of the internalization on the price of willow (€ ton-1 fm) is smaller, but still results in

a price that would lie 44-83% higher (than without internalization), depending on the conversion

technology for which the wood would be used. The impact on the price per ton is lower than the

impact on AGI due to high cultivation costs (especially stool removal), which results in very low

AGI.

Table 3-14 Relative impact of internalization of CO2 based on MAC (i) as a % of original

AGI (€ ha-1), and (ii) as a % of original price (€ ton-1 fm)

Energy

maize

Rapeseed-

PPO-pers

use

Rapeseed -

PPO-tractor

Rapeseed

-

Biodiesel

SRC-

electr.

SRC-

heat

SRC-

CHP

AGI 1,260 1,354 1,195 1,023 111 111 111

Price

biomass 30 477 298 208 28.5 28.5 28.5

MAC CO2

% AGI 21% 6% 6% 9% 111% 180% 96%

% price 15% 5% 8% 13% 51% 83% 44%

AGI=adapted gross income

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4. Contamination in rest product - economic impact

4.1 General

A crucial aspect when growing energy crops on contaminated soil is the fact whether the

harvested crops will be classified as (hazardous) waste, or as biomass since this has an impact on

the further utilization and valorisation of the crop. Elevated metal concentrations in soils cause

increased metal concentrations in plants. Energy conversion of these plants results moreover in a

metal enriched rest product. For a detailed legal analysis we refer to the legal reports submitted

by the Centre for Environmental Sciences (CMK) of Hasselt University.

4.2 Case study

In our case study, the cultivation of energy crops (e.g. energy maize (Zea mays), rapeseed

(Brassica napus), and short rotation coppice of willow (Salix spp.)) for combined sustainable

valorisation and (phyto)remediation of metal contaminated soils in Flanders is considered.

There will always be the need to dispose of residues in the environment because some toxic

constituents cannot be destroyed, or are not commercially interesting. Most literature on the

technology of phytoremediation is fundamental, i.e. studies the process of metal uptake and -

translocation in itself, and merely mentions the external effects (if even named as such), There is

little literature concerning research on (the actual economic valorisation of) externalities resulting

from biomass production on contaminated land.

We suggest not following blind folded the obliged order of the waste management hierarchy as

defined in the European Union (and the Ladder of Lansink in Flanders) and suggest to use a cost-

benefit analysis (preferably accompanied by a Life Cycle Analysis) and choose the option that

generates the largest social benefit or causes the smallest social cost. This is also acknowledged

in preparing the Waste Framework (WF) Directive (2008/98/EC): ”The waste hierarchy

generally lays down a priority order of what constitutes the best overall environmental option in

waste legislation and policy, while departing from such hierarchy may be necessary for specific

waste streams when justified for reasons of, inter alia, technical feasibility, economic viability

and environmental protection.”

Metals are an example of stock pollutants, pollutants that accumulate over time. Environment has

little or no absorptive capacity for them. It is not possible to destroy metals, but we should aim to

find a solution so that they do not pose a threat to current and future generations. A systematic

approach should be developed to find the economically most efficient and cost-effective solution

for biomass produced on contaminated land. Starting from existing regulation on secondary use

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of rest products of energy production we could value the internalization of the presence of metals.

By strictly applying the rules, the presence of metals in the biomass is internalized. This is based

on the assumption that these rules and threshold values are based on e.g. health impact studies.

Table 0-1 Overview of potential end use of rest products for different scenarios, based on

input category (waste or biomass), and on legislation for end product use

Input Conversion

process

Rest

product

Input category Rest product

category

Secondary use

Willow Co-comb.

electricity

Fly+Bottom

ash

Waste/Biomass (10 01) Construction +

landfill†

Co-comb.

heat

Fly+Bottom

ash

Waste/Biomass (10 05) Construction +

landfill†

Co-comb.

CHP

Fly+Bottom

ash

Waste (19 01) Construction +

landfill†

Biomass (10 01) Construction +

landfill†

Maize Anaerobic

digestion

Digestate Waste (19 06 05/06) Fertilizer (11 dm%)‡

Combustion (85

dm%)

Landfill (85 dm%)

Biomass - Fertilizer (11 dm%)‡

Export (85 dm%)‡

Combustion (85

dm%)

Landfill (85 dm%)

Rapeseed PPO Cake Waste/Biomass - Fodder (89 dm%)§

Digestion (89 dm%)

Combustion (89

dm%)

Landfill (89 dm%)

Biodiesel Cake and

glycerine

Waste/Biomass - Fodder (89 dm%)§

Digestion (89 dm%)

Combustion (89

dm%)

Landfill (89 dm%) †VLAREA; ‡on own land, VLAREA ; §Directive 2002/32/EC, and Fodder Decision: maximum

level of Cd for fodder in Belgium (and Europe) expressed as mg kg-1 dm is 1.14

The presence of metals in the residue after conversion of biomass is a scholarly example of an

externality as this fact is not reflected in the price of the original biomass. A transparent and

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comprehensive environmental and economic evaluation of a range of strategies for rest products

should be designed. The aim of this is to economically valorise the effect of metals in the residue,

to be integrated in the total economic value of phytoremediation. The economic impact of metals

on the end use of rest products could be based on current legislation. More specifically, the value

of this externality is calculated based on a comparison of legally accepted options for the

contaminated residue with the best available (economically most efficient) reference option for

uncontaminated residue.

When biomass is uncontaminated, and following existing legislation, digestate should be used as

a fertilizer, with the remaining digestate being combusted. Rapeseed should be used as fodder,

and ashes from willow should be valorised as granulates. For contaminated biomass, strictly

applying current legislation (Table 0-1), applying part of the digestate on the land and

combusting the rest results in the highest value, or the smallest marginal impact of the metals. For

cake, the use as fodder results in no marginal impact from metals. Willow ashes have to be

disposed of because metal concentration is too high.

5. Integration

To answer our research question (part I) we had to answer subquestions. Due to restricted data we

were only able to answer the second part.

Does phytoremediation result in other than private costs and benefits and if so, are these

externalities positive or negative?

Yes, we showed based on an example from the Campine region (BE) that phytoremediation

results in renewable energy potentials with CO2 abatement. Moreover, this impact is positive for

the studied crops. A second externality that we studied in this report is the presence of

contaminants in the biomass. This will have an economic and energetic impact, since the biomass

and the rest product after processing need proper use and disposal which differs from the use or

disposal in the “reference” uncontaminated scenario.

Does phytoremediation offer an economically viable alternative for conventional

remediation technologies and which crops should be used and under what circumstances?

As mentioned previously, the economic analysis was planned at the start of the project. No data

were available yet. Therefore, most of the report is based on data from an existing case study (i.e.

the Campine region in Belgium). As a compromise, we introduced each part with a general

introduction where we indicated the parameters. We then are able to insert these parameters into

the general model as presented in part I of this report. We are convinced that the case study will

make users able to use the suggested approach easily. However, generalizations should be

avoided. Therefore, we do strongly recommend that in the course of the project the necessary

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data are gathered and inserted in the model, before any conclusions on the economic viability are

made.

6. Conclusion




Today, it is widely recognized that cleanup activities of hazardous waste sites may be the cause

of external effects such as the emission of greenhouse gases by the use of heavy duty

construction equipment powered by diesel fuel. Five core elements of green remediation (EPA,

2010) are (i) energy, (ii) air and atmosphere, (iii) water, (iv) land and ecosystems, and (v)

materials and waste. Phytoremediation might be able to deal with all these topics. More

specifically, in this study, we analysed its potential to be a net producer of renewable energy, and

reduce emissions of greenhouse gases to the air. Green remediation factors might even be

included in the evaluation of the economic efficiency. To make the economic analysis for the

project, the necessary physical data should be provided by the other work packages. Therefore,

since we are only at the start of the project, the actual integration will take place when all data are

gathered, at the end of the project. However, this report is valuable in the sense that it serves as a

guideline for the other work packages in gathering necessary data.

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