uks pon1 spill ata analysis 1975 2017 - envaid · every spill to sea leads to environmental damage,...

UKCS PON1 Spill Data analysis

1975-2017

April 2018

PON1 Data Analysis 1975-2017

©EnvAid 2018 1

Contents

Contents ............................................................................................................................ 1

1 Introduction ............................................................................................................... 2 1.1 Scope 3 1.2 Source data 4 1.3 Disclaimer 4

2 Executive summary .................................................................................................... 5 2.1 Absolute data 5 2.2 Context 5 2.3 Normalised performance 6 2.4 Specific installations 7

3 Absolute PON1 data ................................................................................................... 8 3.1 Spill types 9 3.2 Oil spills 10 3.3 Chemical spills 12 3.4 OPPC non-compliances 13 3.5 Timing 14 3.6 Location 15 3.7 Operators 18 3.8 Drilling rigs 18 3.9 Minor sources 20

4 Context ................................................................................................................... 21 4.1 Oil and gas fields 21 4.2 Installations 21 4.3 Oil and gas production 23

5 Normalised PON1 performance ................................................................................. 24 5.1 Oil spills 24 5.2 Chemical spills 26 5.3 Spill potential 29

5.3.1 Fixed and manned oil production installations ............................................................ 29 5.3.2 Floating and manned ................................................................................................... 30 5.3.3 Gas producing installations .......................................................................................... 31

5.4 Installation age 33 5.4.1 Installation year ........................................................................................................... 33 5.4.2 Years of operation ....................................................................................................... 34

6 Specific installations ................................................................................................. 35 6.1 Spill frequency 42 6.2 Spill size 42 6.3 Spill risk 43

Appendix A – Installation sheets ........................................................................................ 46


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1 Introduction

This report is prepared by EnvAid, and is an update of the 2006 TINA Consultants Ltd report titled: Report on the Analysis of DTI UKCS Oil Spill Data for the period 1975-2005. This update includes 43 years of PON1 data from the period 1975-2017. Additional assessments of the more recent spill records from the period 2008-2017 are also provided.

My first involvement with the analysis of spill records was when ConocoPhillips asked me to review their oil spill response plans. One of the features of oil spill contingency plans, as they were called at the time, was the mandatory inclusion of a risk assessment and which purpose was to demonstrate that the pollution risk was acceptable. An approved plan thus created a sense of acceptance and this contributed to its remaining on the shelf until its next mandatory update.

Conoco commissioned me to update their spill contingency plans and their risk assessment. The latter formed the first version of the document in front of you now. The relevance of risk assessments for the planning of an effective response came under further scrutiny when the disastrous spill from the Macondo well in the Gulf of Mexico happened on the 20th of April 2010. This tragedy reminded the World that the worst can happen and it showed that the industry wasn’t prepared for an accident of that magnitude. The public outrage and the political response also reminded my profession that the concept of risk itself is fundamentally flawed. The accident challenged risk assessment in two fundamental ways: a) “how can a low-frequency, high-magnitude risk ever be acceptable?” and b) “what method for the prioritisation of spill prevention and mitigation is acceptable?” It is not surprising that the appetite for an update of this report has been low.

The licensing authorities in the UK responded to the Deepwater Horizon oil spill by imposing a series of additional controls. Industry arguments that the same couldn’t happen in the North Sea were invalid or did not convince. At first, only high-pressure deep-water oil wells required Ministerial approval, but then similar restrictions were introduced for all high-pressure wells, all oil wells, any well, any rig, any producing installation and finally any activity involving the handling of oil or gas. Oil Pollution Emergency Plans all needed to include worst-case (and oftentimes hypothetical) spill scenarios. This all culminated into the publication of the European Directive 2013/30/EU on the safety of offshore oil and gas operations.

The EU Directive does acknowledge that: “the risk assessments and arrangements for major accident prevention should be clearly described and compiled in the report on major hazards”, but at the same time in puts emphasis on the identification of hazards and controls.; as if to aim for the impossible of zero spill risk. No matter how desirable such an outcome is, risk can never be totally eliminated. Risk assessments can make a valid contribution to improvement decisions or they can be ignored. It is a choice with advantages and disadvantages either way.

I take the view that facts matter; that risk is a part of life and that risk reduction needs to remain proportional to the actual risk. It is for this reason that I undertook to update this report.

I dedicate this study to the tens of thousands of people that have helped to realise such a stellar industry spill performance.

Jos Tissen, April 2018


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1.1 Scope

The scope of this study in relation to the overall assessment of spill risk is depicted in Figure 1.1 below. The figure shows, from top to bottom, the pathway between the source of a spill and the environmental sensitivities. Oil and gas facilities are designed to prevent spills. Primary and secondary control measures are working together to this end. Primary control measures are those that are integrated into the design of the process systems, secondary control measures include drain systems and measures that relate to the operation of the facilities. Leaks from failure of primary control measures can normally be contained on the facility, except when the leak occurs over-the-side: straight above the sea.

Figure 1.1 Scope of report in relation to overall oil spill risk1 assessment

1 Risk is the probability and severity of an adverse effect/event occurring. The first risk level in Figure 1.1 combines the

probability of failure of primary control measures and the volume of any leak. The second risk level combines the probability of a spill to sea and the volume of such a spill. The third risk level combines the probability of a spill damaging the environment and the severity of such damage.

Environmental sensitivities

Primary and secondary control measures

Oil spill contingency

Oil spill fate

Spill scenarios

Secondary control measures

Oil inventory Types of oil

Distance to shore Time of the year

Over-the-side equipment failure

Small leaks

Major leaks

Topsides equipment failure

Slow leak scenarios

Rapid leak scenarios

Oil characteristics

Facility

Risk of spill

Risk of spill to the sea

Risk of environmental damage

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Every spill to sea leads to environmental damage, but the nature of the product, the discharge volume, the distance to shore, the time of the year and the effectiveness of the spill contingency measures determine the severity of the damage.

Analysis of PON1 data allows assessment of the risk of a spill to the sea; i.e. of either:

Failure of over-the-side equipment; or

Failure of topsides equipment in combination with failure of secondary control measures.

The data does not tell us why it was not possible to contain a topsides spill on the facility and what its primary cause was, nor does it allow us to assess the risk of environmental damage resulting from a spill.

1.2 Source data

The study is confined to the PON1 data collated by the inspecting authority and made available to the general public via publications on the internet. Individual company oil spill records have not been consulted.

The data straddles a period of 43 years. The data has various issues associated with inconsistency of records. Estimating the size of a spill can be difficult and a certain amount of subjectivity is an integral part of spill records and this has been confirmed by the analysis of PON1 records. Only order of magnitude conclusions can therefore be drawn from this report.

It may also be dangerous to draw too many conclusions from a dataset that has been compiled over a period during which there have been many changes that impacted the data. Over the years, several changes in both reporting procedures and reporting behaviour have occurred. With increasing environmental awareness as the driver, the Regulating Authority has changed the reporting procedures, introduced air surveillance and included chemical spills and non-compliances in the records, whereas the E&P industry introduced environmental management and reporting systems. The purpose of this report is to provide a full interpretation of the PON1 dataset, within the constraints imposed by the limitations of that data.

Some of the trends in the dataset can be explained by these changes, whereas others cannot. In this report, any such changes have been regarded as part of the overall trend. The data has therefore been analysed as a single dataset, as well as in ways that show any trends. From the report it is possible to only interpret resent spill data in an attempt to increase the reliability of the results. On the other hand, analysis of the complete dataset is presented to increase the statistical reliability of the conclusions. It is up to the reader to add his or her own interpretations.

1.3 Disclaimer

The information in this report is true and complete to the best of my knowledge, but I assume no liability for errors or omissions or for conclusions based on the information provided herein.


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2 Executive summary

This report provides perhaps the most comprehensive analysis of the UKCS PON1 records to date. The analysis was undertaken to inform the assessment of spill risk on the UKCS. The study may also serve to inform the spill risk assessment of the offshore oil and gas industry in general.

It should be noted, that the analysis has only allowed for the assessment of the risk of a spill to sea. The most valuable analysis would be of root cause, which the dataset does not provide. The analysis provides no insight into the root cause of spills, nor of the environmental damage that may occur as a result of an oil or chemical spill from offshore E&P activities.

2.1 Absolute data

In the period 1975-2017, 13,024 PON1 were filed. Almost 26,000 tonnes of oil and chemicals were accidentally discharged. These numbers include a number of regulated discharges from the produced water systems, a number of non-compliance reports and some third party spills. Spills of base oil and of OBM are included in the analysis as chemical spills because they are so classified under the Offshore Chemical Regulations (OCR). The number of oil spills seems to have stabilised at around 250 per year. Spills of chemicals were not reported until the introduction of the OCR in 2002.

The relative number of diesel, condensate and hydraulic oil spills has increased significantly over the last 15 years; and since the introduction of the OCR, PON1 numbers are dominated by chemical spills. No single 5-10 year period can be considered representative of the whole 43-year historical dataset. A total of 8,700 oil spills were reported over the report period and almost 15,000 tonnes of oil was accidentally discharged to the sea. In the period 1975-1983 only a few spills of less than 0.01 tonnes were reported, whereas more than 50% of the spills reported in the last ten years were less than 0.01 tonnes. The 11 oil spills greater than 100 tonnes in size, were responsible for 67% of the oil that was spilled.

The 3,300 chemical spills that were reported over the report period spilled 10,000 tonnes of chemicals into the sea. These numbers include a number of OBM spills from before the introduction of the OCR. Chemical spills tend to be larger in size than oil spills and the data reveals a very slow trend towards the reporting of smaller chemical spills. The 16 chemical spills greater than 100 tonnes in size, were responsible for 30% of the chemicals spilled.

As can be expected, it is twice as likely that spills occur during the summer months when offshore activity is greatest. Spills are equally likely to occur in the weekend as they are during weekdays. Most PON1’s have been filed from installations in blocks 3/3, 9/13 and 16/7. The largest volumes were spilled in blocks 14/19, 30/16 and 211/24. There are noticeable differences between reporting cultures of individual operators. It would appear that some companies have not reported their smaller spills, whereas others have developed this into a fine art.

An unknown number of drilling rigs have been employed on the UKCS since 1975. A total of 162 different rigs filed one or more PON1’s. Several rigs changed owners and names over this period. Semi subs are most frequently employed on the UKCS. There are also differences between the reporting cultures of drilling companies.

2.2 Context

The most important trend on the UKCS since 1975 is the steady increase in offshore activity and the report has therefore compensated for this. A total of 446 oil and gas fields have been developed, 287 of which are still in production. Most fields are located in the Southern North Sea and the Central


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North Sea. Most PON1’s originated from oil producing installations. A total of 555 installations were installed to produce the oil and gas and 83 of these have since been removed. Most of the installations were installed in the Southern North Sea where water depth is shallow. Oil and gas production peaked in 1978 and again in 2000, but has been on the decline ever since.

2.3 Normalised performance

After normalisation, a downward trend is seen in the number of spill reports after 1987 and which has now stabilised at less than 1 spill per field per year.

From a risk assessment perspective, the oil spill performance of the industry as a whole (and when normalised by field-years) has moved into the area of ‘low/acceptable risk’. Against the popular KPI of spills per unit of production, and due to reducing production levels, the industry is getting worse at preventing spills. Nevertheless, the UKCS E&P activities have only spilled 2.4 grams of oil per TOE produced. It is most likely that oil is spilled from the topsides of a fixed oil production installation and least likely from a gas producing installation. A floating oil production facility is less likely to spill oil than a fixed oil producing installation.

When normalised against the number of fields in production and the amounts of hydrocarbons produced, the chemical spill performance of the industry is getting worse. Since 2002, the UKCS E&P activities have spilled 5.6 grams of chemicals per TOE produced. From a risk assessment perspective even the chemical spill performance of the industry as a whole has moved into the area of ‘low/acceptable risk’. Chemical spills are most likely to occur from the topsides of floating oil production installations and least likely from a gas producing installation. The spill size distribution does not suggest that smaller chemical spills are not reported.

Perhaps the most insightful finding of this study is that the spill potential of the UKCS E&P industry seems to have a physical limit. Logic and prudence suggest that a Macondo-type spill can happen in UK waters, but the data seems to justify the claim that the spill potential of the industry is capped at a spill of 10,000 tonnes every 1,000 years of operation. Lower estimates apply to certain types of installations and certain types of products. This is still a significant risk that justifies effective spill contingency planning.

It is sometimes argued that earlier installation designs are more prone to causing spills than later designs. However, most oil spills have been caused by installations installed in the period 1975-1986 and by those installed very recently; and most chemical spills by recent designs. It is also sometimes questioned whether the spill risk increases with installations becoming of age. The data suggest that most oil is spilled between 15 and 35 years of production, tapering off thereafter. The data also shows that chemical spills continue to increase as the installations mature.


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2.4 Specific installations

Of the 555 installations that were installed on the UKCS, 175 or 32% did not file any PON1’s during their lifetime. A total of 440 installations (or 79%) filed less than 1 PON1 per year.

An analysis of the PON1’s from 124 installations with the greatest spill risk is included in Appendix A of this report.

Installations with the greatest oil spill risk include: Alwyn North, Balmoral FPV, Beryl Alpha, Beryl Bravo, Brae Alpha, Claymore Alpha, Cormorant North, Fulmar Alpha, Heather Alpha, Montrose Alpha, Ninian Central, Ninian Northern, Ninian Southern and Thistle A. All of these installations have reduced their oil spill risk in recent years. Britannia, Dunbar, Scott and Triton present the greatest chemical spill risk.

Appendix A of the report contains 124 installation specific oil and chemical spill performance sheets. These state when the installations started to operate, how many years they has been in operation and how may PON1’s were filed from the field that they serve. The sheets include tables of their oil and chemical spill history. Graphs are included to visualise the spill history, to visualise the types of products spilled and to compare the installations’ spill size distribution with that of similar installations.


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3 Absolute PON1 data

In the period 1975-2017, 13,024 PON1’s were filed (Table 3.1 and Figure 3.1). Almost 26,000 tonnes of oil and chemicals were accidentally discharged. These PONs include a number of regulated discharges from the produced water systems (see Section 3.4), a number of non-compliance reports and some third party spills. Spills of base oil and of OBM are included in the analysis as chemical spills because they are so classified under the Offshore Chemical Regulations.

Table 3.1: Summary of PON1 records

Type of PON1

1975-2017 2008-2017

Number of PONs

Amount (tonnes)

Number of PONs

Amount (tonnes)

Oil spills 8,698 14,811 2,759 388

Oil based mud spills 707 3,060 183 190

Other chemical spills 2,600 7,094 2,163 4,975

Third party spills 290 59 0 0

OPPC non-compliances 672 1 5 0

OCR non-compliances 57 687 0 0

Totals 13,024 25,712 5,110 5,553

The number of oil spills seems to have stabilised at around 250 per year. Spills of chemicals were not reported until the introduction of the offshore chemicals regulations in 2002 (Figure 3.1).

Figure 3.1: Completed PON1’s over the period 1975-2017

Most oil has been spilled with a small number of large spills during the eighties and early nineties. Most chemicals were spilled in 2005 and 2009 and it is perhaps too early to tell whether the spilled amounts have come down permanently (Figure 3.2).

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Figure 3.2: Discharged amounts over the period 1975-2017

3.1 Spill types

Figure 3.2 summarises the whole 43-year data set, but shifts have taken place over the years. This is depicted in Figure 3.3 below. Spill records from the period 1976-1986 often refer to ‘unknown oil’. It is likely that crude oil was meant. The relative number of diesel, condensate and hydraulic oil spills has increased significantly over the last 15 years. Since the introduction of the OCR, PON1 numbers are dominated by chemical spills.

Figure 3.3: Percentage contribution of different substances to annual spill numbers

Even though 67% of the number of spills relate to oil, 58% of the tonnage of oil spilled to the environment is oil (see Figure 3.4 below).

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Chemical, other Crude oil Diesel oil Drilling chemical Hydraulic fluid OBM Unknown oil Other


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Figure 3.4: Contribution of different substances to annual amounts spilled since 1975

3.2 Oil spills

Figure 3.5 below shows the 8,700 oil spills that were reported over the report period and the almost 15,000 tonnes of oil that was accidentally discharged to the sea.

Figure 3.5: Number of oil spills and amounts spilled

It can be noted that over the years the number of spill reports have increased (with the exception of the periods 1991-1995) and that the years 1977, 1980, 1986-1990 and 1997 stand out with above average discharge amounts. The worst years were 1986, 1988 and 1989. It can also be noted that no single 5-10 year period can be considered representative of the whole 43-year historical dataset.

Further analysis of this is presented in Figure 3.6 below. The Figure includes five Bell curves: one for the 9-year periods between 1975 and 2001 and one for each of the 8-year periods thereafter. The figure does indeed show a trend towards the reporting of small spills. In the period 1975-1983 only a few spills of less than 0.01 tonnes were reported, whereas more than 50% of the spills reported in 2008-2017 were less than 0.01 tonnes. This seems to prove that the slight upward trend after 1995 in the number of spill reports per field as depicted in Figure 5.1 is due to an increase in the reporting of very small oil spills.

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Crude oil Diesel oil Hydraulic fluid Hydraulic oil OBM

Oil mixture Unknown oil Chemical, other Other

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Figure 3.6: Spill size distribution curves for different time periods

As can be seen from Figure 3.7 below, and as could have been expected, a significant proportion of the oil spilled in these peak years was caused by a small number of spills greater than 100 tonnes. Figure 3.7 also reveals that spills greater than 100 tonnes also had a significant influence in the years 1978, 1990 and 1997. The Figure also shows that small oil spills gain in relative importance in the absence of large ones.

Figure 3.7: Amount of oil spilled per spill size category

Table 3.2 below lists the 11 oil spills greater than 100 tonnes that occurred in the report period.

Table 3.2: Oil spills greater than 100 tonnes in size

Date of spill Block Product spilled (interpretation)

Size of spill in tonnes

Stated source and cause of pollution

7-Jan-77 211/29 Crude oil 528 Loading buoy - cleaned by spraying

5-Sep-77 22/18 Crude oil 396 Flange parted during loading. Slick moved slowly. Breaking in 20ft waves

28-Jun-78 22/18 Crude oil 112 Malfunction in separator level control and level alarm allowed carry over of oil.

6-Apr-80 211/24 Crude oil 980 Lost in pipeline rupture. Degraded and dispersed naturally

26-Nov-86 14/19 Crude oil 3,000 Spillage from pipeline

02-Jul-88 211/27 Crude oil 112 Accidental discharge from platform diverter valve failure to open

9-Sep-88 15/17 Crude oil 750 General oil releases following Piper incident

24-Dec-88 30/16 Crude oil 1,504 Floating Storage Unit - breaking away from subsea

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50%

≥100 tonnes

<100 ≥10 tonnes

<10 ≥1 tonnes

<1 ≥0.1 tonnes

<100 ≥ 10 kg

<10 ≥ 1 kg<1 ≥ 0.1 kg<100 g ≥ 10 g

< 10 g ≥ 1 g

Pe

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spil

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Spill size category

1975-1983

1984-1992

1993-2001

2002-2009

2010-2017

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1975 1980 1985 1990 1995 2000 2005 2010 2015

≥100 tonnes <100 ≥10 tonnes <10 ≥1 tonnes <1 ≥0.1 tonnes <100 ≥ 10 kg

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13-Aug-89 Crude oil 1,800 Arising from planned de-oiling operation - flaring of recovered oil

18-Jun-90 Crude oil 112 Possible open valve

24-Aug-97 13/22 Crude oil 685 Upset of produced water system

Total 9,979 This is 67% of total oil spilled

Most of these spills are over-the-side spills, where secondary containment was absent. The spills that occurred on 2 July 1988 and 13 August 1989 are the exceptions. Maybe the magnitude of the leaks associated with these spills caused the secondary containment to overflow.

3.3 Chemical spills

Figure 3.8 below shows the 3,300 chemical spills that were reported over the report period and the over 10,000 tonnes of chemicals that was accidentally discharged to the sea. These include spills of oil based mud (OBM). Before 2002, OBM spills were reported as oil spills and in this analysis reclassified as chemical spills.

Figure 3.8: Number of chemical spills and amounts spilled

Figure 3.9: Spill size distribution curves for different time periods

Figure 3.9 depicts four chemical spills size distribution curves: one for the 9-year periods between 1984 and 2001 and one for each of the 8-year periods thereafter. Chemical spills tend to be larger in size than oil spills and the figure only shows a very slow trend towards the reporting of small spills.

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<100 ≥10 tonnes

<10 ≥1 tonnes

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<10 ≥ 1 kg<1 ≥ 0.1 kg<100 g ≥ 10 g

< 10 g ≥ 1 g

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Spill size category

1984-1992

1993-2001

2002-2009

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As can be seen from Figure 3.10 below, significant discharge volumes continue to determine the risk of chemical spills, but the trend also shows that small chemical spills do gain in relative importance.

Figure 3.10: Amount of chemicals spilled per spill size category

Table 3.2 below lists the 16 chemical spills greater than 100 tonnes that occurred in the report period. The two OBM spills were initially reported as oil spills.

Table 3.3: Chemical spills greater than 100 tonnes in size




25-Nov-1986 OBM 208 Rig was losing stability so mud dumped overboard

7-Jul-1989 211/14 OBM 240 Oil based mud used in the 12-1/4 section, while water based mud used in 8-1/2 section

1-Dec-1989 49/12 Chemical, other 120 Loss of methanol during transfer operations

7-Dec-2003 110/13 Drilling chemical 150 Whilst off-loading brine from the supply vessel the ships propeller parted the bunkering line.

9-Jan-2007 211/23 Chemical, other 157 Possible spill whilst pumping from supply vessel to platform.

1-Jan-2008 2/5 Hydraulic Fluid 231 Subsea hydraulic control fluid release.

28-Jun-2008 43/27 Chemical, other 146 Failure of injection pump

27-Feb-2009 37/25 Drilling chemical 196 Operational failure following mud displacement.

14-May-2009 49/27 Chemical, other 320 Suspected that pipeline was fractured by a fishing vessel.

15-Jul-2009 3/19 Hydraulic fluid 137 Failure of subsea control equipment.

22-Aug-2009 16/7 Hydraulic fluid 216 Failure of hydraulic distribution system.

26-Dec-2010 15/16 Hydraulic Fluid 136 Template shuttle valve seal failure.

10-Nov-2011 44/23 Chemical, other 190 3mm diameter hole in Hunter Flexible Pipeline identified during pipeline testing

17-Dec-2012 113/27 Drilling chemical 139 Wellbore Formation losses / fracture / breach to seabed.

2-Sep-2013 48/20 Chemical, other 189 Tank filling overflow due to faulty level indication and poor operational control

20-Aug-2015 3/4 Hydraulic fluid 250 Hydraulics - Closed system - Umbilical Rupture

Total 3,025 This is 30% of total chemicals spilled

3.4 OPPC non-compliances

Under the provisions of the Offshore Petroleum Activities (Oil Pollution Prevention and Control) Regulations 2005 (OPPC), permits are issued that control the discharge of oil to sea from various planned operational activities on offshore installations including oil in produced water (PW).

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1975 1980 1985 1990 1995 2000 2005 2010 2015


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The permit conditions limit the concentration of oil in PW to a monthly average of 30 mg/l. Discharges made and reported in accordance with permit conditions are legally permitted, and non-compliances are nowadays reported by means of the non-compliance form. Before these forms were introduced, such situations were reported as oil spills. For the purpose of this analysis, these spills have been excluded from the oil spill risk analysis. However, any reports of oil in produced water discharges exceeding 1o kg of oil to sea have retained their oil spill classification.

A total of 672 PON1 reports associated with produced water incidents have been excluded from further analysis. Less than a single tonne of oil was discharged to sea as a result of these incidents (Figure 3.11).

Figure 3.11: OPPC non-compliances excluded from further analysis

3.5 Timing

As can be expected, it is twice as likely that spills occur during the summer months when offshore activity is greatest. See Figure 3.12. It has been suggested that sheens are less likely to form in stormy weather and that there are fewer daylight hours in the winter during which sheens can be seen. Spills are equally likely to occur in the weekend as they are during weekdays (Figure 3.13). Slightly more PON1’s are filed on a Monday or Tuesday.

Figure 3.12: Percentage of spills per month of the year

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Figure 3.13: Percentage of spills per day of the week

Figure 3.14 shows whether spills occurred during a time of elevated vulnerability of seabirds to oil pollution (as per the now dated 1999 JNCC classification). Nine percent of spills occurred in blocks and at times of very high vulnerability. Twenty-six percent occurred when vulnerability was high, 28% when in was moderate and 30% when it was low.

Figure 3.14: Vulnerability of seabirds against oil pollution, spill location and spill timing

3.6 Location

Most PON1’s have been filed from installations in blocks 3/3, 9/13 and 16/7 (Figure 3.15). The largest volumes were spilled in blocks 14/19, 30/16 and 211/24 (Figure 3.16). There is no correlation between spill frequency and water depth.

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Central North Sea Northern NorthSea

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West of Shetland Irish Sea

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Figure 3.15: Number of PON1’s filed per UKCS block

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 13 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 3 0 127 3 1 0

0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 42 0 281 82 0

0 0 0 0 7 2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 24 103 143 18 145 2 0

8 0 1 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 13 0 127 141 71 355 0

0 0 0 0 11 28 0 1 4 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 218 0 17 663 23 0

0 0 0 1 0 0 1 87 2 0 0 0 0 0 0 0 0 0 62 0 0 0 0 0 0 0 0 1 251 0

0 0 0 0 31 0 7 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 0 0 3 136 22

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43 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10 1 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 142 1 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 1 0 0 639 29 6

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 62 4 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 185 19 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 98 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 24 0 0 0 2 0 0 7 728 4 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 0 2 0 0 0 18 2 0 0

0 0 0 0 0 0 0 0 0 0 0 0 9 196 9 116 170 2 0 63 0 59 0 0 0

0 1 0 0 0 0 1 197 0 12 0 0 0 0 0 1 93 219 19 38 2 171 7 5 0 0

0 103 0 0 0 0 0 1 0 0 126 1 0 0 0 10 0 2 3 0 6 149 164 0 101 65 0

0 0 0 0 0 0 0 0 1 0 0 0 0 0 5 50 0 1 9 133 2 6 0 2 0 15 0 0 30 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 99 2 0 0 1 2 0 0 1 223 6 1 0 1 81 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 101 1 4 6 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 3 0 74 2 3 0 5 197 0 61 57 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 8 8 150 115 6 8 111 7 76 1 0 0 0

0 0 0 0 0 0 0 0 0 0 1 0 4 2 17 0 2 5 2 173 69 47 0 0 0

0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 36 54 5 0 45 13 24 10 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 9 0 0 63 2 3 5 31 65 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 7 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 208 183 11 2 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 84 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 67 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 14 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 1 5 9 6 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 3 0 18 0 2 41 15 3 0 0 0 0 0 0

7 4 0 0 0 0 0 4 127 18 62 5 0 0 0 10 0 6 0 0 0 0 0 0 0

0 61 4 0 1 0 0 1 35 0 7 0 8 0 0 0 0 0 0 5 0 0 0 0 0 0

0 1 1 0 0 0 0 0 101 4 5 40 7 0 2 9 1 0 0 2 6 0 0 0 0 0

0 1 105 0 13 0 0 0 0 16 1 8 7 22 2 1 22 72 1 11 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 30 0 42 49 29 6 12 20 3 0 0 0 0 0

0 0 0 0 0 0 0 2 0 1 0 1 16 12 61 6 49 0 0 0 0 0

0 0 0 0 0 1 48 3 2 146 72 1 1 0 0 0 0 0

0 0 0 0 0 0 1 2 4 9 6 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

15 80 145 210 275 340 405 470 535 600 665 730

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Figure 3.16: Amounts spilled per UKCS block

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 9.019587 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.132 0 0 0 0 0 0 0 0 0 0.1326 0 109.0171515 0.037 240 0

0 0 0 0 0 0 1.33 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 57.85635 0 386.1881293 50.965386 0

0 0 0 0 0.134 29.8 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 27.906392 50.985341 269.3283679 3.13151 303.613706 980.4 0

8.53859 0 0.075 0 0 0 0 0 0 0.005 0 0 0 0 0 0 0 0 0 0 0 0 0 0.89039 0 81.6532005 313.741695 71.6577 859.0110077 0

0 0 0 0 1.250717 3.60628 0 0.17 14.77646 0.001 0 0 0 0 0 0 0 0 0 0 0 0 0 0 299.75275 0 7.885842 377.415497 382.450472 0

0 0 0 0.00046 0 0 0.09 11.97698381 0.0098 0 0 0 0 0 0 0 0 0 201.407785 0 0 0 0 0 0 0 0 0.075 159.9927476 0

0 0 0 0 3.3678504 0 0.175894 0.11635 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.514 0 0 1.07 222.9729776 24.81433

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 163.9809804 0

0.23336812 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

6.142377276 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.06 7 0.02 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3.755087 34.75 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 173.5459871 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.5 0 0 0 0 0 0 0 0 0.08 0 0 670.888588 3.49332 33.88

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 201.407785 0.5566 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 24.64140225 15.706529 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2.55 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.014 0 0 0 0 0 9.64513 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 39.68691 0 0 0 0 0 0 2.096 734.8975547 0.41 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.742 0 0 0 0.1627 0 0 0 51.88247 0.006 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0.684 3181.754854 1.928158 227.6496605 956.46016 2.2 0 192.6443609 0 22.5629815 0 0 0

0 0.5 0 0 0 0 0.014 910.9569636 0 42.0622 0 0 0 0 0 4.5 164.40709 108.2656634 7.4231 32.15216 0.1 242.3113546 0.1972 5.9778 0 0

0 101.9011107 0 0 0 0 0 0.1 0 0 56.5739135 0.001 0 0 0 26.694117 0 0.2 1.05 0 30.32869001 205.699224 34.388009 0 56.52213502 125.232764 0

0 0 0 0 0 0 0 0 51.428 0 0 0 0 0 2.779278 55.51680113 0 0.0019 2.6651318 344.154176 0.0611 0.058355 0 1.4023 0 13.792556 0 0 31.4691095 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 16.3159652 0.004545 0 0 0.085 0.04973 0 0 0.01 142.1714134 1.5695 0.0002 0 0.002 49.33026958 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 21.8196255 0.045 1.91448 3.56 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0.0732 0 80.4570779 0.13885 0.0211 0 0.03781 643.1742797 0 37.192936 5.7948741 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 40.26794 0.02172 123.419122 84.8811535 0.8227 1.939 6.764381803 7.192 22.675799 0.002 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0.77024 0.1425 12.262016 0 1.820006 0.199932 7.0712 299.2427936 118.1708685 173.695364 0 0 0

0 0 0 0 0.0007 0 0 0 0 0 0 0 0 0 0 0 11.081225 217.34559 0.052555 0 44.540776 4.13195 25.17836 5.201574 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0.00018 0 0 2.29008 0 0 12.5949192 0.334 0.54083 25.006149 1.227803 13.74116066 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.0009 0 1.044197 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1702.334277 130.6669465 16.40505 0.128 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 171.5959552 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10.82627 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 196 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 28.625 0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0.20027 0 0 0 0 0 0 0 0 0 1.8137732 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 1.915 0.0035 0 3.8 25.32358 0.754854 0.120661 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0.212 0 15.0056 0 0.161 27.963883 214.233503 0.827275 0 0 0 0 0 0

6.028922666 198.92509 0 0 0 0 0 0.9955 48.52372972 24.78946 22.976045 148.8 0 0 0 8.90405 0 0.01375 0 0 0 0 0 0 0

0 13.1499 2.732 0 0.01 0 0 0.0014 26.87358 0 0.3211 0 18.718 0 0 0 0 0 0 1.018225 0 0 0 0 0 0

0 0.001 0 0 0 0 0 0 77.33829967 0.93 2.217471 12.930329 0.97 0 19.800246 4.799238 0.931 0 0 0.031 2.0415 0 0 0 0 0

0 0.13 225.6619505 0 9.42287 0 0 0 0 6.1925 0 2.1442 0.58448 2.775591 0.203 9.94 15.01669 176.44261 5 5.12756 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 12.256981 0 6.183437 196.763652 2.15637206 39.16149 0.069613815 2.149672 29.60075 0 0 0 0 0

0 0 0 0 0 0 0 2.31 0 0.0186 0 10.5 13.366648 4.84245201 31.72526 1.3595 7.052208 0 0 0 0 0

0 0 0 0 0 0.00418 16.66017 0.402 0.042 380.133413 50.850542 8.2 0 0 0 0 0 0

0 0 0 0 0 0 0.05 0.0009 0.07393 0.505 0.988108 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0

8 280 552 824 1096 1368 1640 1912 2184 2456 2728 3000 0 0 0 0 0 0 0 0 0 0 0

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3.7 Operators

Figure 3.17 below, investigates the question whether there is a difference in the oil spill reporting culture between operators. It is sometimes argued that some operators report all of their spills, whereas others only report spills above a certain size. The Figure covers the whole 43-year report period, and has plotted the spills against the operators that currently operate the installations from which the spills occurred. Spills from decommissioned installations have been excluded from this part of the analysis.

Figure 3.17: Spill size distribution per operator; report period

The Figure shows that there indeed are differences. It would appear that Companies 1, 15 and 18 have not reported their smaller spills, whereas Companies 11 and 25 have developed this into a fine art. At the bottom of the graph a bar with the spill size distribution across all PONs from oil and gas production installations has been included for comparison (Industry).

3.8 Drilling rigs

An unknown number of drilling rigs has been employed on the UKCS since 1975. Baker Hughes maintains a worldwide rig count2 and the Europe rig count as presented in Figure 3.18 gives an indication of the drilling activity in the UK. The Figure also plots the number of rigs that have filed PON1’s. A total of 162 different rigs did so. Several rigs changed owners and names over this period (Figure 3.19). Jack-ups and semi subs are most frequently employed (Figure 3.20).

2 Baker Hughes Worldwide Rig Count: http://phx.corporate-ir.net/phoenix.zhtml?c=79687&p=irol-rigcountsintl

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Figure 3.18: Drilling rig activity

Figure 3.19: Current rig names and the number of PON1’s reported while in UK waters

Aban Pearl: 11, Arch Rowan: 7, Atlantic: 1, Atlantic 404: 1, Atlantic Amsterdam: 4, Atlantic Labrador: 6, Atlantic London: 2, Benreoch: 6, Benvrackie: 8, Blackford Dolphin: 32, Blue Beta: 1, Borgholm Dolphin: 4, Borgland Dolphin: 1, Borgny Dolphin: 13, Borgsten Dolphin: 31, Bredford Dolphin: 4, Britannia: 149, Byford Dolphin: 41, Cecil Provine: 4, Charles Rowan: 1, CSO Seawell: 2, Deepsea Aberdeen: 54, Deepsea Bergen: 3, Deepsea Stavanger: 1, Energy Enhancer: 1, Energy Producer 1: 25, Ensco 100: 20, Ensco 101: 29, Ensco 102: 26, Ensco 120: 3, Ensco 5002: 5, Ensco 70: 2, Ensco 72: 6, Ensco 80: 16, Ensco 85: 10, Ensco 92: 17, Ensco 95: 1, Galveston Key: 4, Global Santa Fe: 1, Glomar Adriatic IV: 1, Glomar Arctic IV: 8, GSF Adriatic VI: 3, GSF Arctic I: 6, GSF Arctic II: 4, GSF Arctic III: 52, GSF Arctic IV: 24, GSF Baltic: 1, GSF Britannia: 1, GSF Galaxy I: 21, GSF Galaxy II: 9, GSF Galaxy III: 33, GSF Grand Banks: 4, GSF Labrador: 1, GSF Magellan: 10, GSF Main Pass I: 3, GSF Monarch: 15, GSF Rig: 1, GSF Rig 135: 10, GSF Rig 140: 13, Henry Goodrich: 5, Hunter: 8, J W McLean: 1, Jack Bates: 5, John Shaw: 1, JW McLean: 3, Leiv Eiriksson: 2, Lotos Petrobaltic: 4, M.G.Hulme Good: 1, Maersk Curlew: 58, Maersk Endurer: 2, Maersk Enhancer: 10, Maersk Gallant: 4, Maersk Highlander: 30, Maersk Highlander 1: 4, Maersk Innovator: 1, Maersk Inspirer: 1, Maersk Resilient: 18, Maersk Resolve: 7, Maersk Responder: 3, Maersk Vinlander: 4, Magellan: 1, Marinus Maris: 1, Nantoi Tiao Zhan: 2, Noble Driller: 2, Noble Hans Deul: 3, Noble Lloyd Noble: 4, Noble Scott Marks: 1, Noble Therald Martin: 4, Noble Ton van Langeveld: 1, Norstcot Producer: 1, Northern Producer: 54, Ocean Baroness: 8, Ocean Bounty: 1, Ocean Challenger: 1, Ocean Guardian: 44, Ocean Lubricator: 1, Ocean Nomad: 56, Ocean Patriot: 4, Ocean Princess: 56, Ocean Quest: 1, Ocean Valiant: 6, Ocean Vanguard: 1, Ocean Victory: 1, Paragon B391: 6, Paragon C20051: 2, Paragon C20052: 4, Paragon C461: 1, Paragon C462: 1, Paragon C463: 3, Paragon HZ1: 1, Paragon MSS1: 43, Paragon MSS3: 7, Paul B Loyd Jr: 89, Pentagone 84: 1, Petrolia: 11, Prospector 5: 5, Rowan California: 4, Rowan Gorilla: 5, Rowan Gorilla II: 2, Rowan Gorilla IV: 3, Rowan Gorilla V: 38, Rowan Gorilla VI: 6, Rowan Gorilla VII: 11, Rowan Halifax: 6, Rowan Stavanger: 1, Rowan Viking: 1, Santa Fe Galaxy: 1, Scarabeo 6: 2, Sedco: 3, Sedco 700: 6, Sedco 703: 1, Sedco 704: 44, Sedco 706: 8, Sedco 707: 4, Sedco 711: 39, Sedco 712: 34, Sedco 714: 37, Sedco Drill Star: 12, Sedneth 701: 3, Sonat Arcade Frontier: 1, Sovereign Explorer: 2, Soye Britannia: 1, Stena Carron: 18, Stena Clyde: 1, Stena Dee: 12, Stena Forth: 3, Stena Spey: 38, Swift 10: 2, Transocean 712: 4, Transocean Discoverer: 4, Transocean Explorer: 2, Transocean John Shaw: 29, Transocean Leader: 12, Transocean Prospect: 28, Transocean Rather: 13, Transocean Searcher: 1, Transocean Spitsbergen: 6, Trident: 1, Trident X: 2, Trident XIV: 1, West Navigator: 2, West Phoenix: 53, West Theta: 3, West Venture: 3, Western Pacesetter I: 1, WilHunter: 10, WilPhoenix: 34, Zapata Bonanza: 1

Figure 3.20: PON1’s from drilling rigs, by type of rig

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Figure 3.21 below, investigates the question whether there is a difference in the spill reporting culture between drilling companies. The Figure covers the whole 43-year report period, and has plotted the spills against the operators that currently operate the rigs from which the spills occurred.

Figure 3.21: Spill size distribution per drilling company; report period

The Figure shows that there indeed are differences. It would appear that drilling companies 3, 6, 9, 10, 12 and 13 have not reported their smaller spills, whereas drilling companies 4 and 7 have done so to a great degree. At the bottom of the graph a bar has been included with the spill size distribution across all PONs filed from drilling rigs for comparison (Industry).

3.9 Minor sources

Minor spill sources include the subsea tiebacks (SSTB), support vessels and third-parties. Spill size distribution curves for these sources are shown in Figure 3.22 below. The largest spills occur from tiebacks to gas production installations. Most third party spills are of unknown size.

Figure 3.22: Spill size distribution of minor source spills

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4 Context

The most important trend on the UKCS since 1975 is the steady increase in offshore activity and the report has therefore compensated for this. An accurate measure of offshore activity would take account of changes in drilling, construction and operational activities, but such a measure is not readily available. Normalisers that can be used include: number of fields; number of topsides and production volume. Each of these normalisers have been applied in the report. The number-of-fields measure is suitable for compensating for drilling related activity and the number-of-producing-installations measure for compensating for production related activity. From the perspective of an industry that produces oil and gas, production-volume is perhaps the most relevant normaliser.

This section presents the contextual background of the PON1 record. Data in this section is used to normalise the absolute data as presented in Section 3. The normalised performance is presented in Section 5.

4.1 Oil and gas fields

Figure 4.1 below shows how the number of fields in production on the UKCS has increased in this period. A total of 446 fields have been developed, 287 of which are still in production. Most fields are located in the Southern North Sea (44%) and 33% are located in the Central North Sea.

Figure 4.1: Number of fields in production and their location

In order to compare the dataset relating to these geographical areas of the North Sea, the information presented in Section 3 has been normalised by dividing the number of spills in each area by the sum of the years that the fields in these areas are in production. The northern North Sea has 1,432 field production years, the central North Sea has 2,874 and the southern North Sea 2,540. Areas of lesser activity are West of Shetland (86 field years), the Irish Sea (230 field years) and the Moray Firth (131 field years).

4.2 Installations

As can be seen from Table 4.1 and Figure 4.2 , most PON1’s originate from oil producing installations (9,246 PON1’s). 1,705 PON1’s came from drilling rigs, 1,422 from gas producing installations and 651 from other sources.

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Table 4.1: Types of installations and related PON1’s

Installation type

All PON1’s

Number Spilled

amount

Oil and gas producing facilities

Oil producing facilities

Fixed facility, manned 7,437 10,928

Fixed facility, unmanned 72 21

Fixed facility, subsea tieback 222 657

Floating facility, manned 1,491 4,724

Floating facility, subsea tieback 24 4

Gas producing facilities

Fixed facility, manned 756 818

Fixed facility, unmanned 567 286

Fixed facility, subsea tieback 99 240

Non producing facilities

Drilling rigs

Jack-up 458 1,162

Semi Sub 1,175 3,161

Drill ship 29 14

Unknown 47 164

Pipeline and umbilical 31 1,389

Support vessel 239 1,979

Figure 4.2: PON1 origin

A total of 555 installations were installed to produce the oil and gas. At the time of writing 83 of these have been removed. Most installations (62%) are unmanned or subsea.

Figure 4.3: Number of production installations of a specific type

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When comparing Figure 4.1 with Figure 4.3 above, it becomes clear that although there are more fields in the central and northern North Sea, the greatest number (43%) of installations are located in the southern North Sea as this is where most of the gas fields are located. Shallower water depths make it economic to develop a field by larger numbers of installations.

Figure 4.1 on page 21 shows how many fields have been in production in the years of the period 1975-2017. The Figure also shows how many fields have been in production in the various geographical areas of the North Sea.

The geographical distribution of the various installations that produce these fields is summarised in Table 4.2. Most oil producing facilities are located in the Central North Sea and most gas producing ones in the Southern North Sea. The table includes facilities that have been decommissioned.

Table 4.2: Location of installations

Installation type CNS IS MF NNS SNS WOS

Fixed oil production facility, manned 52 3 5 33 4

Fixed oil production facility, unmanned 6 2 3 1

Fixed oil production facility, SSTB 73 2 34

Floating oil production facility, manned 31 1 3 12 2 4

Floating oil production facility, SSTB 20 4 1 1

Gas production facility, manned 3 3 1 66

Gas production facility, unmanned 2 9 1 129

Gas production facility, SSTB 7 5 1 3 57 2

4.3 Oil and gas production

Another way of normalising the absolute number of spills is to relate these to the oil and gas that was produced. Figure 4.4 shows the oil and gas production from the UKCS in the report period. Over 6 billion tonnes of oil equivalent were produced. Oil and gas production from the UKCS has been on the decline since 2000.

Figure 4.4: Oil and gas production 1975-2016

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5 Normalised PON1 performance

5.1 Oil spills

Amount of oil spilled and numbers of oil spills normalised against the number of fields in production are presented in Figure 5.1 below. The inset shows the last ten years of data on a larger scale. A comparable image emerges when normalised against the number of installations in production.

Figure 5.1: Number of oil spills and spilled amounts normalised by the number of fields in production

Two things are obvious from Figure 5.1. The first is that fewer years stand out as having had extraordinary amounts of oil spilled. The years 1977, 1980, 1986, 1988 and 1989 do, however, continue to deserve a closer look.

The second observation relates to the number of oil spills reported. After normalisation, a downward trend is seen in the number of spill reports after 1987 and which has now stabilised at less than 1 spill per field per year. The upward trend after 1995 as seen in Figure 3.5 seems to be caused by increased activity rather than by an increase in the number of PON1’s. Later in this report you will see that some under-reporting has occurred, but this seems to challenge the general belief that under-reporting of spills occurred in the earlier years of UKCS E&P activity. It is interesting to note the quantities spilled in terms of tonnes/field diminished greatly in the 1990’s. This may be due to a rising uptake of Environmental Management Systems (EMS) by operators, a process which requires a systematic approach to spill prevention and reporting.

The oil spill data has again been normalised against the number of fields in production in Figure 5.2 below. The same trend towards smaller spill volumes as noted in Section 3.2 can be observed. In addition, the downward trend in the number of spill reports per field per year is clearly visible.

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©EnvAid 2018 25

Figure 5.2: Distribution of spill size and likelihood (normalised per field)

The most important point of Figure 5.2 is, however, made by having plotted the graph as a typical risk assessment graph, where the x-axis is a measure of consequence and the y-axis a measure of frequency with areas of high, moderate and low risk overlaid. It can be seen that the Bell-curves are moving to the left over time, towards the bottom left ‘green’ area. From a risk assessment perspective Figure 5.2 therefore suggests that the oil spill performance of the industry as a whole has moved into the area of ‘low/acceptable risk’.

The total oil and gas production expressed in tonnes of oil equivalent was used to calculate Figure 5.3. For the period up to 1997, the result is very similar to Figure 5.1. After normalisation by oil and gas production, a downward trend is seen in the number of spill reports after 1987, but not as pronounced as in Figure 5.1. The stabilisation of the trend after 1995 as seen in Figure 3.5 and Figure 5.1 does not materialise here because oil and gas production has decreased, whereas the number of fields has increased. This may be a result of the newer discoveries being smaller than the earlier ones. Against this popular KPI, the industry is getting worse at preventing spills. Nevertheless, the UKCS E&P activities have only spilled 2.4 grams of oil per TOE produced; a containment efficiency of 99.9998 %.

Figure 5.3: Number of oil spills and spilled amounts per unit of production

Figure 5.4 confirms that overall (i.e. over the whole 43-year dataset); it is most likely that oil is spilled from the topsides of a fixed oil production installation and least likely from a gas producing installation. In contrary to common belief, a floating oil production facility is less likely to spill oil than a fixed oil producing installation.

0.0

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<100 ≥10 tonnes

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<10 ≥ 1 kg<1 ≥ 0.1 kg<100 g ≥ 10 g

< 10 g ≥ 1 g

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Figure 5.4: Spill size distribution curves for different topsides; report period

This still applies when considering data from the last ten years (Figure 5.5). Here, it can also be observed that oil spills from gas producing installations have increased.

Figure 5.5: Spill size distribution curves for different topsides; period 2008-2017

5.2 Chemical spills

Amount of chemicals spilled and numbers of chemical spills normalised against the number of fields in production and the amounts of hydrocarbons produced are presented in Figure 5.6 and Figure 5.7 below. The performance of the industry is getting worse against both performance indicators. Since 2002, the UKCS E&P activities have spilled 5.6 grams of chemicals per TOE produced.

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Figure 5.6: Number of chemical spills and spilled amounts normalised by the number of fields in production

The chemical spill data has again been normalised against the number of fields in production during these periods, and this has resulted in Figure 5.2 below. The same cautious trend towards smaller spill volumes as noted earlier can be observed.

Figure 5.7: Distribution of spill size and likelihood (normalised per field)

Figure 5.7 plots the graph as a risk assessment graph. Slowly the Bell-curves are moving to the left over time, toward the bottom left ‘green’ area. From a risk assessment perspective Figure 5.7 therefore suggests that even the chemical spill performance of the industry as a whole in moving toward the area of ‘low/acceptable risk’.

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Figure 5.8: Number of chemical spills and spilled amounts per unit of production

Figure 5.9 shows that chemical spills are most likely to occur from the topsides of floating oil production installations and least likely from a gas producing installation. The spill size distribution does not suggest that smaller chemical spills are not reported. Due to the fact that chemical spills were not reported as such before the introduction of the offshore chemicals regulations in 2002, the graph suggests a lower than actual spill risk.

Figure 5.9: Spill size distribution curves for different topsides; report period

A more accurate depiction of chemical spill risk is obtained when considering data from the last ten years (Figure 5.10). The greatest chemical spill risk is again presented by floating oil producing facilities and the larger spill sizes are noticeable when compared to the oil spill risk for the same period (Figure 5.5).

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Figure 5.10: Spill size distribution curves for different topsides; period 2008-2017

5.3 Spill potential

This section is perhaps the most insightful section of this study. By displaying the spill size distribution curves in a different way, an indication of spill potential can be derived from the PON1 records. This section includes such an analysis for the key types of production installations and for the key types of substances spilled. The derived spill potentials are summarised in Table 5.1. These are still significant risks that justify effective spill contingency planning, but are a lot lower than the volumes spilled with the Macondo and IXTOC 1 spills in the Gulf of Mexico.

Table 5.1: UKCS spill potential expressed as a change of a spill of x tonnes in 1,000 years

Type of installation Period

Type of spill

Oil Chemical

Crude / condensate

Hydraulic oil

Oily water Diesel Hydraulic

fluid Chemical,

other

Oil producing

Fixed facility, manned

1975-2017 < 1,000 < 1,000

< 1,000 < 10 < 100 < 1,000 < 10,000 < 100

2008-2017 < 100 < 1,000

Floating facility, manned

1975-2017 < 10,000 < 1,000

< 1,000 < 1,000 - < 10 < 1,000 < 1,000

2008-2017 < 1,000 < 1,000

Gas producing Fixed facility, manned

1975-2017 < 100 < 1,000

< 100 < 100 - < 10 - < 1,000

2008-2017 < 100 < 10,000

5.3.1 Fixed and manned oil production installations

The spill potential of manned fixed oil producing installations is shown in Figure 5.11 and Figure 5.12. The point where the lines stop and the angle at which they decline both provide an indication of spill potential. If there has not been a hydraulic oil spill greater than 10 tonnes in the entire history of UKCS oil and gas production, then it is not very likely that a greater one would occur. The point where the graph lines intersect or would intersect with the once in a 1,000 year spill frequency line provides a solid indication of the spill potential of the UKCS installations (and arguably further afield). As argued in the introduction, this doesn’t exclude the possibility of a larger spill, it merely indicates that larger spills are not likely. Three graph lines in Figure 5.11 intersect with the bottom of the graph before the 1,000 tonnes mark on the horizontal axis. The oil spill line for the past ten years does so before the 100 tonne mark.

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Figure 5.11: Fixed and manned oil production facility; likelihood and size of oil and gas spills

Four graph lines in Figure 5.12 stop before the 10 tonne mark; indicating that the PON1 records do not contain any larger spills. It is therefore not likely that spills of those types greater than 10 times that size (i.e. 100 tonnes) will occur. A similar argument applies to the spill potential of “chemicals, other”. The greatest spill potential seems to involve a spill of hydraulic fluid. A subsea leak of hydraulic fluid does not have a logical limit.

Figure 5.12: Fixed and manned oil production facility; likelihood and size of spill types

5.3.2 Floating and manned

The spill potential of manned floating oil producing installations is shown in Figure 5.13 and Figure 5.14. Three graph lines in Figure 5.13 stop before the 100 tonne mark; indicating that the PON1 records do not contain any larger spills. It is therefore not likely that spills of those types greater than 1,000 tonnes will occur. The oil spill line for the period 1975-2017 intersects with the bottom of

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Diesel oil Hydraulic fluid Chemical, other

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©EnvAid 2018 31

the graph before the 10,000 tonnes mark on the horizontal axis. This fits with the potential to spill oil from FPSO storage tanks.

Figure 5.13: Floating and manned oil production facility; likelihood and size of oil and gas spills

Four graph lines in Figure 5.14 stop before the 100 tonne mark; indicating that the PON1 records do not contain any larger spills. It is therefore not likely that spills of those types greater than 1,000 tonnes will occur. The line for crude oil even intersects with the bottom of the graph before the 100 tonne mark. The line for diesel stops before the 1 tonne mark, making a diesel spill larger than 10 tonnes unlikely (this despite the potential being there).

Figure 5.14: Floating and manned oil production facility; likelihood and size of spill types

5.3.3 Gas producing installations

The spill potential of manned fixed gas producing installations is shown in Figure 5.15 and Figure 5.16. One of the graph lines in Figure 5.15 stops before the 10 tonne mark; indicating that the PON1 records do not contain any larger spills. It is therefore not likely that oil spills greater than 100 tonnes

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will occur. The oil spill lines for both periods intersect with the bottom of the graph before the 100 tonnes mark on the horizontal axis. The line representing the chemical risk for the past ten years suggests that there is a spill potential of 10,000 tonnes. This may relate to a subsea leak of hydraulic fluid.

Figure 5.15: Fixed and manned gas production facility; likelihood and size of oil and gas spills

One of the graph lines in Figure 5.16 stops before the 1 tonne mark; indicating that it is not likely that diesel spills greater than 10 tonnes will occur. The line for hydraulic oil intersects with the bottom of the graph before the 100 tonne mark. The line for condensate stops before the 10 tonne mark, making it unlikely that a condensate spill greater than 100 tonnes would occur. The line for “chemicals, other”, does not decline, suggesting a spill potential that exceeds the typical storage capacity for these types of chemicals.

Figure 5.16: Fixed and manned gas production facility; likelihood and size of spill types

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5.4 Installation age

This section investigates the correlation between installation age and spill risk. Both the year of installation and the years of operation at the time of the spill have been considered.

5.4.1 Installation year

It is sometimes argued that earlier installation designs are more prone to causing spills than later designs. This section investigates this point. The numbers of oil and gas producing installations that have been installed on the UKCS during the report period are shown in Figure 5.17. Most installations have been installed in the nineties.

Figure 5.17: Number of installations installed during the report period

However, most oil spills have been caused by installations installed in the period 1975-1986 and those installed very recently (Figure 5.18). Relatively more chemical spills also originated from installations installed recently.

Figure 5.18: Number of spills per installation age category; report period

Please note that Figure 5.18 displays the number of spills over the entire report period, and that this may not been representative for the performance of these installations in recent years.

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5.4.2 Years of operation

In addition to the question whether an old design contributes negatively to the spill risk, the question is sometimes asked whether the spill risk increases with installations becoming of age. This section analyses the PON1 data from this point of view.

Figure 5.19 shows the number of oil and chemical spills by installations in their various years of operation. The trends suggest that most oil is spilled between 15 and 35 years of production, tapering off thereafter. Please remember that oil spill sizes have decreased over time.

The trend also shows that chemical spills continue to increase as the installations mature. The latter finding may have been influenced by the fact that chemicals spills have only been reported since the introduction of the OCR.

Figure 5.19: Number of spills per year of operation

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©EnvAid 2018 35

6 Specific installations

Of the 555 installations that were installed on the UKCS (Table 6.1), 175 or 32% did not file any PON1’s during their lifetime. A total of 440 installations (or 79%) filed less than 1 PON1 per year. See Figure 6.1.

Figure 6.1: PON1 frequency distribution

Table 6.1: List of installations that were installed on the UKCS

Installation name

Location Field Number of PON1’s per

year

Affleck CNS Affleck 0.0

AH001 CNS Rob Roy 3.7

Ailsa Craig NNS Emerald 0.2

Alba FSU CNS Alba 0.3

Alba Northern CNS Alba 4.8

Alder CNS Alder 1.0

Alison SNS Alison 0.2

Alwyn North NNS Alwyn North 7.6

Alwyn North NAB

NNS Alwyn North 0.5

Amethyst SNS Amethyst East 0.3

Amethyst A2D SNS Amethyst East 0.0

Amethyst B1D SNS Amethyst East 0.1

Amethyst C1D SNS Amethyst West 0.0

Anasuria CNS Guillemot A 1.9

Andrew CNS Andrew 4.0

Anglia A SNS Anglia 0.1

Anglia YM SNS Anglia Western 0.1

Ann XM SNS Ann 0.1

Annabel SNS Annabel 0.2

Aoka Mizu CNS Ettrick 2.1

Apollo SNS Apollo 0.2

Arbroath CNS Arbroath 1.4

Ardmore SNS Ardmore 0.3

Arkwright CNS Arkwright 0.0

Armada CNS Armada 1.7

Installation name


year

Armada Kraken

NNS Kraken 2.0

Artemis SNS Artemis 0.0

Arthur SNS Arthur 0.1

Arundel CNS Arundel 0.0

Athena FPSO MF Athena 1.8

Atlantic CNS Atlantic 0.1

Atlas SNS Atlas 0.0

Audrey WD SNS Audrey 0.1

Audrey WM SNS Audrey WM 0.0

Audrey XW SNS Audrey 0.2

Auk Alpha CNS Auk 1.7

Auk North CNS Auk North 0.1

Aviat SNS Aviat 0.0

Babbage SNS Babbage 1.0

Bains IS Bains 0.3

Baird SNS Baird 0.0

Balmoral FPV CNS Balmoral 5.0

Barque PB SNS Barque 0.7

Barque PL SNS Barque South 0.1

Beatrice A MF Beatrice 2.3

Beatrice AP MF Beatrice 0.0

Beatrice Bravo MF Beatrice 0.2

Beatrice Charlie

MF Beatrice 0.1

Beauly CNS Beauly 0.1

Beryl Alpha NNS Beryl 7.0

0%

5%

10%

15%

20%

25%

30%

35%

0

40

80

120

160

200

0 1 2 3 4 5 6 7 8 9 10 11 12 13

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Installation name


year

Beryl Bravo NNS Beryl 9.0

Bessemer SNS Bessemer 0.2

Birch CNS Birch 0.2

Bittern CNS Bittern 0.6

Blair CNS Blair 0.0

Blake MF Blake 0.3

Blane CNS Blane 0.2

Bleo Holm MF Ross 6.2

Boulton H SNS Boulton H 0.1

Boulton-BM SNS Boulton 0.1

Brae Alpha CNS Brae South 12.8

Brae Bravo CNS Brae North 4.9

Brae Central CNS Brae Central 0.1

Brae West CNS Brae West 0.1

Braemar CNS Braemar 0.2

Breagh A SNS Breagh 0.2

Brechin CNS Brechin 0.0

Brenda NNS Brenda 0.1

BRENT A NNS Brent 1.1

BRENT B NNS Brent 2.1

BRENT C NNS Brent 3.1

BRENT D NNS Brent 1.8

BRENT FLARE NNS Brent 0.0

Brent South NNS Brent South 0.0

Brent Spar NNS Brent South 0.7

Brigantine BG SNS Brigantine A/B/C/D 0.2

Brigantine BR SNS Brigantine A/B/C/D 0.2

Britannia CNS Britannia 7.5

Britannia BLP CNS Brodgar 0.0

Brown SNS Brown 0.0

Bruce NNS Bruce 3.4

Bruce CR NNS Bruce 0.2

Bruce D NNS Bruce 0.8

Bruce PUQ NNS Bruce 1.1

Buchan Alpha CNS Buchan 2.2

Buckland NNS Buckland 0.1

Bure SNS Bure 0.0

Bure West SNS Bure West 0.0

Burghley CNS Burghley 0.1

Burgman CNS Burgman 0.0

Buzzard P NNS Buzzard 2.5

Buzzard PS NNS Buzzard 0.0

Buzzard UQ NNS Buzzard 2.1

Buzzard W NNS Buzzard 0.6

Caister CM SNS Caister 0.2

Calder IS Calder 0.1

Caledonia MF Caledonia 0.0

Callanish CNS Callanish 0.4

Callisto ZM SNS Callisto 0.1

Installation name


year

Camelot Central and South

SNS Camelot C&S 0.0

Camelot North SNS Camelot North 0.0

Camelot North East

SNS Camelot North East

0.0

Captain BLP MF Captain 0.3

Captain FPSO MF Captain 2.2

Captain WPP A MF Captain 6.1

Caravel SNS Caravel 0.2

Carrack East SNS Carrack East 0.2

Carrack QA SNS Carrack 0.5

Carrack West SNS Carrack West 0.0

Catcher CNS Catcher 3.0

Causaway NNS Causaway/Fionn 0.7

Cavendish SNS Cavendish 0.0

Cawdor CNS Cawdor 0.0

Ceres SNS Ceres 0.0

Chanter CNS Chanter 0.0

Chiswick SNS Chiswick 0.5

Cladhan NNS Cladhan 0.0

Clair WOS Clair 6.0

Clair DP WOS Clair Ridge 7.5

Clair QC WOS Clair Ridge 0.3

Clapham CNS Clapham 0.1

Claymore Alpha

CNS Claymore 4.9

Claymore CAP CNS Claymore 0.0

Cleeton CP SNS Cleeton 3.4

Cleeton CT SNS Cleeton 0.1

Cleeton CW SNS Cleeton 0.5

Cleeton PK SNS Cleeton 0.0

Clipper SNS Clipper 1.5

Clipper PK SNS Clipper 0.0

Clipper PR SNS Clipper 0.3

Clipper PT SNS Clipper 0.8

Clipper PW SNS Clipper 0.2

Clipper South SNS Clipper South 0.0

Clyde CNS Clyde 3.7

Columba B Terrace

NNS Columba B Terrace 0.0

Columba D Terrace

NNS Columba D Terrace

0.0

Columba E Terrace

NNS Columba E Terrace 0.0

Conwy IS Conwy 1.0

Cook CNS Cook 0.1

Cormorant Alpha

NNS Cormorant S 2.4

Cormorant Central

NNS Cormorant Central 0.0

Cormorant North

NNS Cormorant N 3.5


©EnvAid 2018 37

Installation name


year

Corvette SNS Corvette 0.3

Crathes CNS Crathes/Scolty 0.0

Curlew C CNS Curlew C 0.0

Cutter QC SNS Cutter 0.1

Cygnus A PU SNS Cygnus 2.0

Cygnus A QU SNS Cygnus 0.3

Cygnus A WD SNS Cygnus 0.0

Cygnus Bravo SNS Cygnus 8.0

Cyrus CNS Cyrus 0.1

D18a-A SNS Orca 0.0

Dalton IS Dalton 0.4

Dauntless CNS Dauntless 0.0

Davy SNS Davy 0.2

Davy East SNS Davy East 0.0

Davy North SNS Davy North 0.1

Dawn SNS Dawn 0.0

Deben SNS Deben 0.0

Deepsea Pioneer

CNS Innes and Argyll 6.0

Delilah SNS Delilah 0.1

Della SNS Della 0.0

Devenick CNS Devenick 0.5

Don NNS Don 0.0

Don SW NNS Conrie 0.0

Douglas IS Douglas 2.7

Douglas DP IS Douglas 0.0

Douglas DW IS Douglas 0.0

Dunbar NNS Dunbar 5.2

Duncan CNS Duncan 0.1

Dunlin Alpha NNS Dunlin 2.9

Dunlin South West

NNS Dunlin South West 0.0

East Brae CNS Brae East 3.7

Egret CNS Egret 0.0

Eider Alpha NNS Eider 1.4

Elgin B CNS Elgin 0.0

Elgin PUQ CNS Elgin 2.4

Elgin WHP1 CNS Elgin 0.9

Ellon NNS Ellon 0.3

Emerald NNS Emerald 0.8

Enochdhu CNS Enochdhu 0.0

EnQuest Producer

CNS Alma and Galia 3.0

Ensign SNS Ensign 0.2

Eris SNS Eris 0.1

Erskine CNS Erskine 0.6

Esmond CP SNS Esmond 0.2

Esmond CW SNS Esmond 0.0

ETAP CPF CNS Monan 2.1

ETAP Mungo CNS Mungo 2.1

Europa SNS Europa 0.2

Installation name


year

Everest North Production

CNS Everest 2.9

Everest North Riser

CNS Everest 0.1

Excalibur SNS Excalibur 0.3

Falcon NNS Falcon 0.0

Farragon CNS Farragon 0.1

Fergus CNS Fergus 0.0

Flora CNS Flora 0.0

Flyndre CNS Flyndre 0.5

Forbes SNS Forbes 0.0

Forties A CNS Forties 1.5

Forties B CNS Forties 0.7

Forties C CNS Forties 1.0

Forties D CNS Forties 1.0

Forties E CNS Forties 0.6

Forties Unity CNS Forties 0.7

Forvie NNS Forvie North 0.1

FPF-1 SNS Stella 3.0

Franklin CNS Franklin 0.5

Fulmar AD CNS Fulmar 0.0

Fulmar Alpha CNS Fulmar 3.4

Fulmar FSU CNS Fulmar 0.4

Fulmar SALM CNS Fulmar 0.0

Gadwall CNS Gadwall 0.0

Galahad SNS Galahad 0.3

GALLEON PG SNS Galleon 0.4

Galleon PM SNS Galleon 0.1

GALLEON PN SNS Galleon 0.2

Galley CNS Galley 0.4

Gannet A CNS Gannet A 3.8

Gannet B CNS Gannet B 0.1

Gannet C CNS Gannet C 0.2

Gannet D CNS Gannet D 0.7

Gannet E/F CNS Gannet E/F 0.5

Gannet G CNS Gannet G 0.0

Ganymede-ZD SNS Ganymede 0.1

Garrow SNS Garrow 0.0

Gawain SNS Gawain 0.0

Glamis CNS Glamis 0.0

Glas Dowr CNS Durward 1.0

Glen Lyon WOS Quad204 Schiehallion and Loyal

9.0

Global Producer III

CNS Donan and Dumbarton

6.7

Golden Eagle PUQ

NNS Golden Eagle 2.8

Golden Eagle WP

NNS Golden Eagle 1.0

Goldeneye MF Goldeneye 0.6

Goosander CNS Goosander 0.0


©EnvAid 2018 38

Installation name


year

Gordon SNS Gordon 0.0

Grant NNS Grant 0.0

Grouse CNS Grouse 0.0

Grove SNS Grove 0.5

Gryphon Alpha NNS Gryphon 1.7

Guinevere SNS Guinevere 0.2

Hæwene Brim CNS Pierce 2.1

Halley CNS Halley 0.0

Hamilton IS Hamilton 0.1

Hamilton East IS Hamilton East 0.0

Hamilton North

IS Hamilton North 0.1

Hamish CNS Hamish 0.0

Hannay NNS Hannay 0.0

Harding NNS Harding 8.3

Harrier SNS Harrier 0.0

Hawksley EM SNS Hawksley 0.1

Heather Alpha NNS Heather 5.2

Helvellyn SNS Helvellyn 0.0

Heron CNS Heron 0.0

Hewett 48/29 A

SNS Hewett 0.5

Hewett 48/29 B

SNS Hewett 0.1

Hewett 48/29 Q

SNS Hewett 0.0

Hewett 48/29-FTP

SNS Hewett 0.1

Hewett 52/5 A SNS Hewett 0.2

Highlander CNS Highlander 0.2

Horne/Wren SNS Horne/Wren 0.3

Hoton SNS Hoton 0.4

Howe CNS Howe 0.0

Hudson NNS Hudson 0.8

Hummingbird CNS Chestnut 1.1

Hunter SNS Hunter 0.7

Hutton TLP NNS Hutton 3.7

Hyde SNS Hyde 0.5

Inde 49/18 AQ SNS Indefatigable (BP) 0.1

Inde 49/18 AT SNS Indefatigable (BP) 0.1

Inde 49/18 BD SNS Indefatigable (BP) 0.0

Inde 49/18 BP SNS Indefatigable (BP) 0.1

Inde 49/23 AC SNS Indefatigable (BP) 0.1

Inde 49/23 AD SNS Indefatigable (BP) 0.6

Inde 49/23 AP SNS Indefatigable (BP) 0.1

Inde 49/23 CD SNS Indefatigable (BP) 0.1

Inde 49/23 CP SNS Indefatigable (BP) 0.2

Inde 49/23 D SNS Inde South West 0.2

Inde JD SNS Indefatigable (Shell)

0.1

Inde JP SNS Indefatigable (Shell)

0.1

Installation name


year

Inde K SNS Indefatigable (Shell)

0.1

Inde L SNS Indefatigable (Shell)

0.0

Inde M SNS Indefatigable (Shell)

0.0

Inde N SNS Indefatigable (Shell)

0.0

Iona CNS Iona 0.0

Islay NNS Islay 0.3

Ivanhoe CNS Ivanhoe 0.0

Jacky MF Jacky 0.1

Jade CNS Jade 0.8

James CNS James 0.0

Janice Alpha CNS Janice 3.4

Jasmine LQ CNS Jasmine 0.6

Jasmine WP CNS Jasmine 0.6

Joanne CNS Joanne 0.2

Judy CNS Judy 1.6

Judy RP CNS Judy 0.2

Juliet SNS Juliet 0.0

Jura NNS Jura 0.5

Katy SNS Katy 0.0

Keith NNS Keith 0.1

Kelvin SNS Kelvin 0.1

Kestrel NNS Kestrel 0.2

Ketch SNS Ketch 0.1

Kew SNS Kew 0.0

Kilmar SNS Kilmar 0.3

Kingfisher CNS Kingfisher 0.1

Kinnoull CNS Kinnoull 0.0

Kittiwake A CNS Kittiwake 2.5

Kittiwake KLB CNS Kittiwake 0.2

Kyle CNS Kyle 0.4

Laggan WOS Laggan 0.3

Lancelot SNS Lancelot 0.4

Leadon NNS Leadon 0.1

Leman 49/27 AC

SNS Leman (BP) 0.0

Leman 49/27 AD

SNS Leman (BP) 0.1

Leman 49/27 AX

SNS Leman (BP) 0.5

Leman 49/27 BD

SNS Leman (BP) 0.0

Leman 49/27 BP

SNS Leman (BP) 0.0

Leman 49/27 BT

SNS Leman (BP) 0.0

Leman 49/27 CD

SNS Leman (BP) 0.0

Leman 49/27 CP

SNS Leman (BP) 0.0


©EnvAid 2018 39

Installation name


year

Leman 49/27 DD

SNS Leman (BP) 0.0

Leman 49/27 DP

SNS Leman (BP) 0.0

Leman 49/27 ED

SNS Leman (BP) 0.0

Leman 49/27 EP

SNS Leman (BP) 0.0

Leman 49/27 FD

SNS Leman (BP) 0.0

Leman 49/27 FP

SNS Leman (BP) 0.1

Leman 49/27 G SNS Leman (BP) 0.1

Leman 49/27 H SNS Leman (BP) 0.1

Leman 49/27 J SNS Leman (BP) 0.0

Leman AD1 SNS Leman (Shell) 0.8

Leman AD2 SNS Leman (Shell) 0.0

Leman AK SNS Leman (Shell) 0.2

Leman AP SNS Leman (Shell) 0.5

Leman AQ SNS Leman (Shell) 0.3

Leman BD SNS Leman (Shell) 0.1

Leman BH SNS Leman (Shell) 0.0

Leman BK SNS Leman (Shell) 0.0

Leman BP SNS Leman (Shell) 0.1

Leman BT SNS Leman (Shell) 0.0

Leman CD SNS Leman (Shell) 0.0

Leman CP SNS Leman (Shell) 0.1

Leman D SNS Leman (Shell) 0.1

Leman E SNS Leman (Shell) 0.1

Leman F SNS Leman (Shell) 0.1

Leman G SNS Leman (Shell) 0.1

Lennox IS Lennox 0.5

Leven CNS Leven 0.0

Linnhe NNS Linnhe 0.0

Lochranza CNS Lochranza 0.0

Lomond CNS Lomond 3.1

Loyal WOS Loyal 0.1

Lyell NNS Lyell 0.3

MacAdam MM SNS McAdam 0.3

Machar CNS Machar 0.3

Maclure NNS Maclure 0.0

Madoes CNS Madoes 0.1

Maersk Curlew CNS Curlew 2.8

Magnus NNS Magnus 3.1

Magnus South NNS Magnus South 0.0

Mallard CNS Mallard 0.0

Malory SNS Malory 0.1

Maria CNS Maria 0.0

Markham SNS Markham (UK) 0.0

Marnock PDR CNS Marnock 6.4

Marnock QU CNS Marnock 0.2

Maureen Alpha CNS Maureen 2.4

Installation name


year

MCP-01 NNS Franklin 0.6

Medwin CNS Medwin 0.0

Mercury SNS Mercury 0.2

Merlin NNS Merlin 0.0

Miller CNS Miller 5.0

Millom East IS Millom 0.3

Millom West IS Millom 0.0

Mimas SNS Mimas 0.1

Minerva SNS Minerva 2.4

Minke SNS Minke 0.3

Mirren CNS Mirren 0.2

Moira CNS Moira 0.0

Montrose Alpha

CNS Montrose 3.7

Montrose BLP CNS Montrose 0.0

Mordred SNS Mordred 0.0

Morecambe CPC-1

IS Morecambe South 0.8

Morecambe DP1


Morecambe DP3


Morecambe DP4


Morecambe DP6


Morecambe DP8


Morecambe North

IS Morecambe North 0.5

Munro SNS Munro 0.1

Murchison NNS Murchison 2.1

Murdoch K SNS Murdoch K 0.1

Murdoch MA SNS Murdoch 0.0

Murdoch MC SNS Murdoch 0.1

Murdoch MD SNS Murdoch 0.8

N. VALIANT 1 PD

SNS Valiant North 0.1

N. VALIANT 2 SP

SNS Valiant North 0.0

Nelson CNS Nelson 4.2

Neptune SNS Neptune 0.7

Ness NNS Ness 0.0

Nevis NNS Nevis 0.1

Newsham SNS Newsham 0.2

Ninian Central NNS Ninian 6.0

Ninian Northern

NNS Ninian 4.2

Ninian Southern

NNS Ninian 6.6

Nordic Apollo CNS Banff 0.0

North Hewett 48/29 C

SNS Hewett 0.1


©EnvAid 2018 40

Installation name


year

North Sea Producer

CNS MacCulloch 1.6

North West Hutton

NNS Hutton NW 5.5

Northern Producer

CNS Galley, Don West and Don SW

5.4

Northsea Pioneer

NNS Crawford 0.3

Nuggets NNS Nuggets 0.1

NW Bell SNS Bell 0.2

Orion CNS Orion 0.0

Orwell SNS Orwell 0.0

OSI IS Douglas 1.1

Osprey NNS Osprey 0.7

Otter NNS Otter 0.0

Pelican NNS Pelican 0.5

Penguin East NNS Penguin East 0.5

Penguin West NNS Penguin West 0.0

Peregrine CNS Peregrine 0.0

Petrojarl 1 CNS Bladon, Hudson, Blenheim and Angus

2.0

Petrojarl Foinaven

WOS Foinaven 3.8

Petronella CNS Petronella 0.0

Pickerill A SNS Pickerill 0.2

Pickerill B SNS Pickerill 0.1

Pict CNS Pict 0.2

Piper Alpha CNS Piper 4.9

Piper Bravo CNS Piper 2.9

Ranform Banff CNS Banff 2.0

Ravenspurn North CPP

SNS Ravenspurn North 1.8

Ravenspurn North ST2


Ravenspurn North ST3


Ravenspurn North WT1


Ravenspurn South A

SNS Ravenspurn South 0.3

Ravenspurn South B


Ravenspurn South C


Renee CNS Renee 0.0

Rhum NNS Rhum 0.1

Rhyl IS Rhyl 0.0

Rita SNS Rita 0.1

RND ST2/3 SNS Johnston 0.1

Rochelle CNS Rochelle 0.0

Rose SNS Rose 0.1

Rosebank FPSO

WOS Rosebank 0.0

Installation name


year

Rough AD SNS Rough 0.3

Rough AP SNS Rough 0.5

Rough BD SNS Rough 0.6

Rough BP SNS Rough 1.1

Rough CD SNS Rough 0.5

Rubie CNS Rubie 0.0

S Morecambe AP1


Saltire CNS Saltire 0.8

Saturn SNS Saturn 0.1

Saxon CNS Saxon 0.0

Scapa CNS Scapa 0.1

Schiehallion WOS Schiehallion 7.8

Schooner SNS Schooner 0.4

Scoter CNS Scoter 0.3

Scott CNS Scott 7.9

Scott JU CNS Scott 0.4

Scott South CNS Scott South 0.0

Sean PD SNS Sean 0.4

Sean PP SNS Sean 0.8

Sean RD SNS Sean 0.3

Sedgwick CNS Sedgwick 0.0

Seillean CNS Donan 1.0

Sevan Voyageur

CNS Shelley 0.5

Seven Seas SNS Seven Seas 0.5

Seymour WHPS

CNS Seymour 0.2

Shamrock SNS Shamrock 0.0

Shearwater CNS Shearwater 2.1

Shearwater C CNS Shearwater 2.1

Skene NNS Skene 0.0

Skiff SNS Skiff 0.2

Skua CNS Skua 0.0

Solan WOS Solan 11.0

Solitaire CNS Solitaire 0.7

ST1 CNS Larch 0.0

Staffa NNS Staffa 0.2

Stamford SNS Stamford 0.1

Starling CNS Starling 0.0

Stirling CNS Stirling 0.0

Strathspey NNS Strathspey 0.5

Sycamore CNS Sycamore 0.0

Tartan Alpha CNS Tartan 2.4

Teal CNS Teal 0.0

Teal South CNS Teal South 0.0

Telford CNS Telford 0.3

Tern NNS Tern 3.3

Tethys SNS Tethys 0.1

Thames AP SNS Thames 2.0

Thames AR SNS Thames 0.1


©EnvAid 2018 41

Installation name


year

Thames AW SNS Thames 0.2

Thelma CNS Thelma 0.0

Thistle A NNS Thistle 5.3

Tiffany CNS Tiffany 1.9

Toni CNS Toni 0.2

Tormore WOS Tormore 0.0

Trent SNS Trent 0.8

Trent CP SNS Trent 0.0

Tristan NW SNS Tristan NW 0.0

Triton CNS Guillemot West 5.1

Tullich NNS Tullich 0.1

Tweedsmuir CNS Tweedsmuir 0.3

Tyne SNS Tyne North and South

0.4

Uisge Gorm CNS Fife 2.6

Valiant South-TD

SNS Valiant South 0.0

Vampire OD SNS Vampire 0.1

Vanguard-QD SNS Vanguard 0.2

Varadero CNS Varadero 0.0

VICTOR JD SNS Victor 0.1

VICTOR JM SNS Victor 0.0

Victoria SNS Victoria 0.1

Viking AC SNS Viking A 0.0

Viking AD SNS Viking A 0.0

Viking AP SNS Viking A 0.3

Viking AR SNS Viking A 0.1

Viking BA SNS Viking B 1.1

Viking BC SNS Viking B 0.0

Viking BD SNS Viking B 0.2

Viking BP SNS Viking B 0.0

Viking CD SNS Viking B 0.1

Viking DD SNS Viking B 0.0

Viking ED SNS Viking B 0.1

Viking FD SNS Viking B 0.0

Installation name


year

Viking GD SNS Viking B 0.1

Viking HD SNS Viking B 0.0

Viking KD SNS Viking B 0.1

Viking LD SNS Viking B 0.1

Viscount VO SNS Viscount 0.1

Vixen VM SNS Vixen 0.0

Voyageur Spirit

CNS Huntington 1.0

VULCAN RD SNS Vulcan 0.2

VULCAN UR SNS Vulcan 0.1

Watt QM SNS Watt 0.0

Waveney SNS Waveney 0.4

Welland SNS Welland NW & Welland S

0.4

Wenlock SNS Wenlock 0.0

West Franklin CNS Franklin 0.3

West Sole WA SNS West Sole 0.2

West Sole WAP

SNS West Sole 0.0

West Sole WAS

SNS West Sole 0.0

West Sole WB SNS West Sole 0.1

West Sole WC SNS West Sole 0.1

Western Isles FPSO

NNS Western Isles 1.0

Whittle SNS Whittle 0.1

Windermere SNS Windermere 0.0

Wingate SNS Wingate 0.1

Wollaston SNS Wollaston 0.0

Wood CNS Wood 0.0

Yare SNS Yare 0.0

York SNS York 0.2

Ythan NNS Ythan 0.0


©EnvAid 2018 42

The spill risk of 124 of these installations is assessed by combining their spill frequency and their average spill size. Both the spill frequency and the spill size are determined for the entire report period and for the period 2008-2017. Bandings are used to make the information more accessible. Installation specific spill performance sheets are included in Appendix A.

6.1 Spill frequency

The spill frequency ranking of individual installation is placed into the performance bands as defined in Table 6.2. The Table also shows how many installations fall into each band.

Table 6.2: Spill frequency performance banding and number of installations in each band

Band Spills per year Number of

installations in report period

Number of installations in

period 2008-2017

1 <1 83 95

2 ≥1 and <2 26 18

3 ≥2 and <3 9 5

4 ≥3 and <4 2 2

5 ≥4 and <5 0 2

6 ≥5 4 2

Totals 124 124

6.2 Spill size

The spill size ranking of individual installation is placed into the performance bands as defined in Table 6.3.

Table 6.3: Spill size performance banding and number of installations in each band

Band Tonnes of oil or

chemicals spilled per year

Number of installations in report period

Number of installations in

period 2008-2017

A <0.25 62 80

B ≥0.25 and <0.5 12 6

C ≥0.5 and <0.75 5 6

D ≥0.75 and <1 8 7

E ≥1 and <1.25 4 5

F ≥1.25 33 20

Totals 124 124


©EnvAid 2018 43

6.3 Spill risk

Installations in the upper-right corner (6/F) are relatively high risk, whereas installations towards the bottom-left corner (1/A) can be considered low risk.

Figure 6.2: Individual installations – oil spill risk 1975-2017

Sp

ill v

olu

me

ba

nd

F OSI, Rough BP

Auk Alpha, Beatrice A, Buchan Alpha, Petrojarl Foinaven, Forties A, Tartan Alpha

Bruce, Captain FPSO, Cormorant Alpha, Dunlin Alpha, Everest North Production, Golden Eagle PUQ, Kittiwake A, Magnus, Tern

Balmoral FPV, Claymore Alpha, Cormorant North, Fulmar Alpha, Montrose Alpha, Ninian Northern

Heather Alpha, Thistle A

Alwyn North, Beryl Alpha, Beryl Bravo, Brae Alpha, Ninian Central, Ninian Southern

E BRENT A, Anasuria AH001

D Gryphon Alpha Viking BA Brent C Alba Northern, Scott

C BRENT B, Tiffany Clyde, Gannet A Global Producer III Brae Bravo, Solan

B Arbroath, Armada, Forties B, Forties C, Inde 49/23 AD, Jade, Lancelot

Ranform Banff, Eider Alpha, North Sea Producer, Piper Bravo

Uisge Gorm, Triton, Harding, Janice Alpha, Lomond, Nelson

A See Note below

Clipper, Northern Producer, Douglas, Elgin PUQ, ETAP CPF, ETAP Mungo, Ravenspurn North CPP, Shearwater, Shearwater C

Andrew, East Brae, Britannia, Buzzard P, Cleeton CP, Cygnus Bravo, Dunbar, Bleo Holm

Captain WPP A, Clair, Marnock PDR

Clair DP

1 2 3 4 5 6

Note: Cell 1/A contains the following installations that present the lowest spill risk of these 124 installations: Alba FSU, Alwyn North NAB, Barque PB, Bruce D, Bruce PUQ, Buzzard UQ, Hummingbird, Clipper PT, Maersk Curlew, Elgin WHP1, Erskine, Aoka Mizu, Forties D, Forties E, Forties Unity, Hewett 48/29 A, Hyde, Judy, Leman 49/27 AX, Leman AD1, Leman AP, Leman AQ, Lennox, Minerva, Morecambe CPC-1, Morecambe North, Murdoch MD, Neptune, Hæwene Brim, Rough BD, Rough CD, Rough AD, Rough AP, Saltire, Scott JU, Sean PD, Sean PP, Trent, West Sole WA and LOGGS


©EnvAid 2018 44

Figure 6.3: Individual installations – oil spill risk 2008-2017

Sp

ill v

olu

me

ba

nd

F Anasuria Petrojarl Foinaven, Claymore Alpha

Golden Eagle PUQ

E Dunlin Alpha, Tern, Ninian Central

D Gryphon Alpha Armada, Ranform Banff

C Forties B, Jade Scott Solan, Everest North Production

B North Sea Producer, Brae Bravo, Kittiwake A

Sean PP, Piper Bravo, Tiffany, Global Producer III

Nelson, Beatrice A, Cormorant North, Thistle A

Cormorant Alpha, Balmoral FPV

A See Note below See Note below

Clipper, ETAP Mungo, Cygnus Bravo, Harding, Brent B, Captain FPSO, Magnus, Montrose Alpha, Ninian Northern, Heather Alpha

Cleeton CP, Dunbar, Clair, Lomond, Clyde, Gannet A, Fulmar Alpha, Beryl Alpha

Captain WPP A, Brent C

Marnock PDR, Clair DP, Alwyn North

1 2 3 4 5 6 Note: Cell 1/A contains the following installations that present the lowest spill risk of the selected 124 installations: Alba FSU, Barque PB, Hummingbird, Maersk Curlew, Erskine, Forties D, Forties E, Forties Unity, Hewett 48/29 A, Hyde, Leman 49/27 AX, Leman AP, Leman AQ, Lennox, Minerva, Morecambe CPC-1, Morecambe North, Murdoch MD, Neptune, Rough AD, Rough AP, Saltire, Scott JU, Sean PD, Trent, West Sole WA, Douglas, ETAP CPF, Shearwater, East Brae, Britannia, Inde 49/23 AD, Lancelot, Uisge Gorm, Triton, Viking BA, OSI, Tartan Alpha and Beryl Bravo.

Note: Cell 2/A contains the following installations: Alwyn North NAB, Bruce D, Bruce PUQ, Buzzard UQ, Clipper PT, Elgin WHP1, Aoka Mizu, Judy, Leman AD1, Hæwene Brim, Rough BD, Rough CD, LOGGS, Northern Producer, Elgin PUQ, Ravenspurn North CPP, Shearwater C, Andrew, Buzzard P, Bleo Holm, Arbroath, Forties C, Eider Alpha, Janice Alpha, Alba Northern, Brent A, AH001, Rough BP, Auk Alpha, Buchan Alpha, Forties A, Bruce, Brae Alpha, Ninian Southern.


©EnvAid 2018 45

Figure 6.4: Individual installations – chemical spill risk 2008-2017

Sp

ill v

olu

me

ba

nd

F

Alwyn North, Beatrice A, Bruce, Clipper PT, Cormorant North, Anasuria, Leman AD1, Neptune, Hæwene Brim, Shearwater

Captain WPP A, Clyde, Northern Producer, Global Producer III, Northern Producer, Ninian Southern, Piper Bravo

Britannia, Triton Dunbar, Scott

E Janice Alpha, Lomond

Gannet A, Bleo Holm

Claymore Alpha

D Armada, Beryl Alpha, Gryphon Alpha, Montrose Alpha, Trent

Aoka Mizu, Petrojarl Foinaven

C Brae Bravo, Hummingbird, Dunlin Alpha, Leman AP

Clair, Tern

B Arbroath, Ranform Banff, Magnus

ETAP Mungo Marnock PDR Solan

A See Note below

Brae Alpha, Buzzard UQ, Cleeton CP, Ninian Central, Shearwater C

BRENT B, Clair DP, Cygnus Bravo

Harding

1 2 3 4 5 6 Note: Cell 1/A contains the following installations that present the lowest spill risk of the selected 124 installations: Alba FSU, Alba Northern, Alwyn North NAB, Andrew, Auk Alpha, Balmoral FPV, Barque PB, Beryl Bravo, East Brae, BRENT A, BRENT C, Bruce D, Bruce PUQ, Buchan Alpha, Buzzard P, Captain FPSO, Clipper, Cormorant Alpha, Maersk Curlew, Douglas, OSI, Eider Alpha, Elgin PUQ, Elgin WHP1, Erskine, Everest North Production, Uisge Gorm, Forties A, Forties B, Forties C, Forties D, Forties E, Forties Unity, Fulmar Alpha, Golden Eagle PUQ, Heather Alpha, Hewett 48/29 A, Hyde, Inde 49/23 AD, Jade, Judy, Kittiwake A, Lancelot, Leman 49/27 AX, Leman AQ, Lennox, North Sea Producer, Minerva, ETAP CPF, Morecambe CPC-1, Morecambe North, Murdoch MD, Nelson, Ninian Northern, Ravenspurn North CPP, AH001, Rough BD, Rough BP, Rough CD, Rough AD, Rough AP, Saltire, Scott JU, Sean PD, Sean PP, Tartan Alpha, Thistle A, Tiffany, Viking BA, West Sole WA and LOGGS.


©EnvAid 2018 46

Appendix A – Installation sheets

Installation sheets are available for the following 124 installations:

AH001 102 Alba FSU 1 Alba Northern 2 Alwyn North 3 Alwyn North NAB 4 Anasuria 66 Andrew 5 Aoka Mizu 52 Arbroath 6 Armada 7 Auk Alpha 8 Balmoral FPV 9 Barque PB 11 Beatrice A 12 Beryl Alpha 13 Beryl Bravo 14 Bleo Holm 103 Brae Alpha 17 Brae Bravo 16 BRENT A 18 BRENT B 19 BRENT C 20 Britannia 21 Bruce 22 Bruce D 23 Bruce PUQ 24 Buchan Alpha 25 Buzzard P 26 Buzzard UQ 27 Captain FPSO 28 Captain WPP A 29 Clair 31 Clair DP 32 Claymore Alpha 33 Cleeton CP 34 Clipper 35 Clipper PT 36 Clyde 37 Cormorant Alpha 39 Cormorant North 38 Cygnus Bravo 41 Douglas 44

Dunbar 46 Dunlin Alpha 47 East Brae 15 Eider Alpha 48 Elgin PUQ 49 Elgin WHP1 50 Erskine 51 ETAP CPF 88 ETAP Mungo 92 Everest North Production 53 Forties A 56 Forties B 57 Forties C 58 Forties D 59 Forties E 60 Forties Unity 61 Fulmar Alpha 62 Gannet A 63 Global Producer III 43 Golden Eagle PUQ 64 Gryphon Alpha 65 Hæwene Brim 99 Harding 68 Heather Alpha 69 Hewett 48/29 A 70 Hummingbird 30 Hyde 71 Inde 49/23 AD 72 Jade 73 Janice Alpha 74 Judy 75 Kittiwake A 76 Lancelot 77 Leman 49/27 AX 78 Leman AD1 79 Leman AP 80 Leman AQ 81 Lennox 82 LOGGS 124 Lomond 83 Maersk Curlew 40 Magnus 85

Marnock PDR 86 Minerva 87 Montrose Alpha 89 Morecambe CPC-1 90 Morecambe North 91 Murdoch MD 93 Nelson 94 Neptune 95 Ninian Central 96 Ninian Northern 97 Ninian Southern 98 North Sea Producer 84 Northern Producer 42 OSI 45 Petrojarl Foinaven 55 Piper Bravo 100 Ranform Banff 10 Ravenspurn North CPP 101 Rough AD 107 Rough AP 108 Rough BD 104 Rough BP 105 Rough CD 106 Saltire 109 Scott 110 Scott JU 111 Sean PD 112 Sean PP 113 Shearwater 114 Shearwater C 115 Solan 116 Tartan Alpha 117 Tern 118 Thistle A 119 Tiffany 120 Trent 121 Triton 67 Uisge Gorm 54 Viking BA 122 West Sole WA 123


©EnvAid 2018 47

The installation specific oil and chemical spill performance sheets included in this Appendix include the information as shown in the following example:

The first block provides the name and type of the installation, when it started to operate and how many years it has been in operation.

It also shows how many PON1’s were filed that were associated with the field.

The spill history shows the number of oil and chemical spills and the amounts spilled per year. Please note that this excludes produced water spills under 1o kg and third party spills.

The two small Tables on the right show how the installation performed on a standardised risk matrix.

The cumulative spill history visualises and totals the information in the spill history tables.

This Graph compares the spill size distribution curves of the installation with that of similar installations.

This graph displays the types of oil and chemicals that were spilled from the installation. The average amounts discharged are displayed; both for the pre-2008 period and for the most recent years of operation.

uks pon1 spill ata analysis 1975 2017 - envaid · every spill to sea leads to environmental damage,...

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