groundwater qualitative monitoring in bulgaria rossitza gorova – executive environment agency at...
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Groundwater Qualitative Monitoring in Bulgaria
Rossitza Gorova – Executive Environment Agency at the Ministry of Environment and Water
e-mail: [email protected]
1
National Groundwater qualitative monitoring network: past and present situation
The Groundwater monitoring in the frame of the Ministry of Environment and Water existed from 1980
Now it contains 220 operating sampling points (this part which is maintained in the frames of the Ministry of Environment and Waters) – tube wells, shaft wells, springs and pumping stations.
They are sampling 4 or 2 times per year. The observed parameters are: Obligatory – temperature, pH, Dissolved Oxygen, Eh, COD (Mn),
Electrconductivity, Calcium, Magnesium, Sodium, Potassium, Iron, Manganese, Hydrocarbonates, Chloride, Sulphate, Phosphates, Ammonium, Nitrates, Nitrites, Total Solids.
Once per year the heavy metals have been analysed Once per year in accordance with hydrogeological and ecological
conditions are analysed pesticides, PCBs, etc.
Raster Hydrogeological map Scale 1:200 000
Vector geological map of Bulgaria in Scale 1:100 000
Vector hydrogeological map of Bulgaria in Scale 1:500 000
Vector map with groundwater bodies and qualitative monitoring sampling sites
Results from assessment of GW monitoring network under the project
In National data base 803 points are available
401 are for quantity – NIMH – 30 art.wells, 286 wells and 94 springs
263 sampling sites are available in ExEA DB – for quality
NIMH has 130 points for quality – 62 wells and 68 springs
Some analyses of groundawater monitoring network
7% of these points coincide with one another – needs data verification!
73% of points are inside GWBs’ boundaries (version 3)
25% are outside these boundaries 3% needs further investigations 1% are need delineation of new GWB 33% of GWB (58 GWBs) don’t have monitoring
points at all 20 GWBs have only one monitoring point
New groundwater network for chemical status
416 monitoring points – shaft wells, tube wells, springs or drainages
Can we use surface water – rivers near to the springs – base flow without waste water recharge as representative points for groundwater?
Now all country is covered with groundwater bodies
No GWB without monitoring points are available – at least one point per GWB
New chemical parameters for groundwater monitoring are included in compliance with WFD
and Draft Groundwater Directive as well:
• 1-st group - phisico-chemical: Temperature, pH, Total mineralization, Total alkalinity, Dissolved Oxygen, Eh, COD (Mn), Electrconductivity, Calcium, Magnesium, Sodium, Potassium, Iron, Manganese, Hydrocarbonates, Carbonates, Chloride, Sulphate, Phosphates, Ammonium, Nitrates, Nitrites, Total Solids.
• 2-nd group – Heavy metals and arsenic: Pb, Cd, Cu, Zn, Ni, Cr6+, Cr3+, As, Hg; Specific organic compounds: Trichloroethylene, Tetrachloroethylene, pesticides (Annex 3, Regulation N-1 Exploration, use and protection of groundwater, except p. 86, 87 and 88).
GW Database
Data of groundwater bodies characterics
The monitoring results from measurements
and analyses
Data for characterisation of the
groundwater sampling sites
Surveylance monitoring
Objectives: validate risk assessment; Confirming good status of GW-body; Assess long term trends
Principles for selection of Monitoring Sites – 4 main factors:• conceptual model (hydro(geo)logical characteristics, pressures, receptors)• assessment of risk and level of confidence incl. distribution of key pressures• practical considerations concerning monitoring stations (e.g. long-term
access)• monitoring of those parts that are most susceptible Selection of determinands: core suite: dissolved oxygen, pH, el.
conductivity, nitrate, ammonium, temperature, major ions and trace ions; contaminants reflecting pressures;
• for natural background – additional selective determinands Proposed frequency: depending on aquifer flow type; initial and long term
frequency - may be different and may depend on parameter and on existing knowledge of GW-system
3.1 концептуален модел
• регионален• локален
3.2 Интегриран мониторинг
3.5 мониторингова мрежа/ преглед и актуализиране
3.4 типове водоносни хоризонти3.3 групиране на ПВТ за
целите на мониторинга
Operational monitoring
Objectives:status assessment for all GW-bodies identified as being at risk; assessment for significant and sustained upward trends of any pollutant
Principles for selection of Monitoring Sites – main factors:• conceptual model (hydro(geo)logical characteristics, pressures, receptors)• assessment of risk and level of confidence incl. distribution of key pressures• practical considerations concerning monitoring stations (e.g. long-term access)• additional monitoring sites may be required - where risk issues relate to
specific receptors or where pressures and risk issues relate to GW itself e.g. diffuse sources of pollution sampling points will be more distributed across the body (see also CIS 2.8)
• practical considerations for site selection e.g. existing sites, multi purpose monitoring, springs, ...
• selection of determinands – similar to surveillance monitoring and based on surv. monitoring results
• Proposed frequency: depending on aquifer flow type, susceptibility to pollution, initial and long term frequency - may be different and may depend on parameter
4.2 Operational Monitoring
TE
SWB
Protected area monitoring
• Existing guidance on protected areas not repeated
• DW protected areas➔ Monitoring needs to assess DWPA objectives➔ Recommendation for monitoring of representative selection
of potable sources in GW-bodies not at risk as part of surveillance monitoring
➔ In “at risk” bodies: monitoring of all significant potable sources at least once before and once within each RBMP period
➔ Existing raw water quality data can be used➔ Safeguard zones may be used to focus monitoring
Prevent or limit monitoring
• In principle covered by other directives e.g. landfill directive,… – defensive monitoring see GW 3
• But:
– WFD monitoring should help to assess the effectiveness of measures introduced to prevent or limit inputs
Quality of GW-monitoring data
• Overview of factors contributing to quality assurance and to be expanded in the CMA
• Focus on GW-specific QA issues:
– Reliability of conceptual model
– Performance of the monitoring programme
– Sampling procedure and sample treatment
– reference to relevant ISO standards for GW (ISO 5667)
Reporting – link to WG D
• Documentation of monitoring programmes– Considering the development of “Reporting sheets” –
Proposal: summary table for key figuresType of sampling sites in %
GW-body
Area [km²]
Body at
risk? [y/n]
No of sites
No of spring
s
Transbound
ary GW-body
Monitoring wells
Private supply
Centralised DW
supply
Industry
Agricultural use
other
• Complemented by:– Verbal description of monitoring strategy, selection of determinands, investigated GW-
layer, etc.– Tables comprising parameters suites and monitoring frequency– Transboundary issues: bilateral agreement reached on monitoring strategies with
neighbouring country
“Tiered Approach”
Стъпки
• Стъпка 1: Природни фонови стойности• Стъпка 2: Според качествените
стандарти, които се възприемат според типа на рецептора
• Стъпка 3: Отчита се “Фактор на разреждане”
• Стъпка 4:Отчита се “Фактор на самопречистване”
Определяне на прагови стойности в стъпка 2а – на базата на природните фонови концентрации
и референтни стойности – съответните качествени стандарти
Референтни стандарти, предложени за използване при стъпковия подход
GWB 149 – N-Q aquifer Svilengrad-Stambolovo
• This a transboundary GWB with Turkey and Greece• 2 monitoring points for quality are available• Human pressure is available part of the point
pollution sources are shown• Diffuse sources of pollution – land use• Arable land – 55%• Permanent crops – 7%• Permanent pastures – 8%• Forest & Woodland – 26%• Urban areas – 4%• Other – 1%