Groundwater Qualitative Monitoring in Bulgaria

Rossitza Gorova – Executive Environment Agency at the Ministry of Environment and Water

e-mail: gorova@nfp-bg.eionet.eu.int

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%