UK UK10 10 Western Wales In summary the GWB delineation method was as follows: • Define ‘aquifer types’; • Sub-divide into manageable units within catchment abstraction management (CAMS) boundaries; and • Further sub-divide or amalgamate with respect to pressure and impact distributions as appropriate. Define ‘Aquifer Types’ The definition of aquifer types is based on 1:250K digital geological maps and definition of aquifer types by national and local hydrogeological experts. This resulted in three solid geology aquifer types - principal, secondary and unproductive strata - which can be mapped to cover all of the River Basin District according to definitions as follows: • ‘principal’ aquifers – those with significant resources which need to be managed through abstraction licensing in order to prevent over-exploitation, or those with a significant role in sustaining groundwater dependent ecosystems; • ‘secondary’ aquifers – which also have significant resources but with hydraulic properties which limit over-exploitation. These aquifers would not normally warrant special consideration from an abstraction point of view but may still support important abstractions and dependent ecosystems which may be subject to risks associated with pollution pressures; • ‘unproductive strata’ – mostly limited to Tertiary and Jurassic Clays (e.g. London, Oxford, Kimmeridge Clays etc.), which are generally unable to support abstractions greater than 10 m3/d, are unlikely to provide significant baseflow or wetland discharges, and will be considered as ‘not at risk’ without further analysis. Significant Drift aquifers were also defined where significant groundwater resources occur within the drift overlying unproductive strata. Elsewhere drift aquifers overlying productive solid formations are considered as part of the same, layered groundwater body. Having categorised the formations as mapped into these types, GIS based techniques were employed to dissolve small inliers of one aquifer type within another so as to avoid creation of ‘micro-bodies’. We have not presented maps of overlapping aquifers. This means that confined areas of principal aquifers (e.g. the Chalk ‘principal’ aquifer underlying the London Clay ‘unproductive strata’) are not shown. There will also be many areas where drift aquifers, which could be classified as groundwater bodies in their own right, overlie more significant ‘principal’ or ‘secondary’ solid aquifer types. In these cases a single groundwater body will be defined but managed according to its hydrogeological characteristics. This simplified representation was necessary for characterisation, risk assessment, classification and national mapping purposes. A three-dimensional delineation of groundwater bodies will be introduced in future river basin management planning cycles as conceptual models for the individual aquifers develop. Following expert review, the size criteria were changed for some of the most productive sandstone aquifers (Sherwood Sandstone). This was because there are areas where the outcrop/subcrop (as marked on the 1:250,000 map) is quite small but yet the resource potential is significant in connection with the rest of the aquifer. This was resolved by including all the outcrop areas irrespective of the size of the outcrop. 10605-21-7 Carbendazim 0.075 µg/l 75 Groundwater body 1071-83-6 Glyphosate 0.075 µg/l 75 Groundwater body 120-36-5 Dichlorprop 75 µg/l 75 Groundwater body 122-34-9 Simazine 0.075 µg/l 75 Groundwater body 139-40-2 Propazine 0.075 µg/l 75 Groundwater body 14265-44-2 Phosphate 74.9948 93.5 µg/l 75 Groundwater body 15545-48-9 Chlorotoluron 0.075 µg/l 75 Groundwater body 1582-09-8 Trifluralin 0.075 µg/l 75 Groundwater body 16118-49-3 Carbetamide 0.075 µg/l 75 Groundwater body 1702-17-6 Clopyralid 0.075 µg/l 75 Groundwater body 1912-24-9 Atrazine 0.075 µg/l 75 Groundwater body 1912-26-1 Trietazine 0.075 µg/l 75 Groundwater body 206-44-0 Fluoranthene 0.1451 µg/l 75 Groundwater body 21725-46-2 Cyanazine 0.075 µg/l 75 Groundwater body 25057-89-0 Bentazon 0.075 µg/l 75 Groundwater body 31218-83-4 Propetamphos 0.075 µg/l 75 Groundwater body 330-54-1 Diuron 0.075 µg/l 75 Groundwater body 333-41-5 Diazinon 0.0145 µg/l 75 Groundwater body 34123-59-6 Isoproturon 0.075 µg/l 75 Groundwater body 470-90-6 Chlorfenvinphos 0.075 µg/l 75 Groundwater body 52315-07-8 Cypermethrin 0.075 µg/l 75 Groundwater body 67129-08-2 Metazachlor 0.075 µg/l 75 Groundwater body 7429-90-5 Aluminium 61 61 µg/l 75 Groundwater body 7440-02-0 Nickel 0 9.3615 µg/l 75 Groundwater body 7440-23-5 Sodium 31 31 mg/l 75 Groundwater body 7440-47-3 Chromium 0 1.85 µg/l 75 Groundwater body 7440-50-8 Copper 0 24.44 µg/l 75 Groundwater body 7440-66-6 Zinc 0 89.3866 µg/l 75 Groundwater body 75-99-0 Dalapon 0.075 µg/l 75 Groundwater body 7664-41-7 Ammonia 0 0.3 mg/l 75 Groundwater body 886-50-0 Terbutryn 0.075 µg/l 75 Groundwater body 93-65-2 Mecoprop 0.075 µg/l 75 Groundwater body 94-74-6 MCPA 0.075 µg/l 75 Groundwater body Cadmium 0.3505 µg/l 75 Groundwater body Chloride 53 53 mg/l 75 Groundwater body Conductivity 520 520 µS/cm 75 Groundwater body Lead 10.4446 µg/l 75 Groundwater body Nitrates 8 8 mg/l 75 Groundwater body Sulphate 36 36 mg/l 75 Groundwater body Threshold values are groundwater quality standards that have generally been set at a local groundwater body scale, for the purpose of assessing groundwater chemical status. They are triggers, such that their exceedance prompts further investigation to determine whether the conditions for good status have been met, rather than representing the boundary between good and poor status. The groundwater quality standards prescribed in the GWD for nitrate and pesticides are used in the assessment process in the same way. However, if all standards and thresholds are met at all monitoring points then, under Article 4.2(b) of the GWDD, the groundwater body is considered to be at good status and no further investigation is necessary. The process of setting threshold values is complex. Initially, component threshold values (referred to as criteria values in EC CIS guidance) have been derived for the purpose of assessing each of the tests for good chemical status. The threshold/criteria values are derived by taking into account the relevant criteria for protection of each receptor. For example values may be derived from surface water environmental quality standards or from drinking water standards. In each case the natural background concentrations are taken into account such that a threshold value will not be lower than the upper limit of the natural background concentration within the groundwater body. This only applies to naturally occurring substances. In determining threshold values the source characteristics and properties of the pollutant has bee taken into account as well as the attenuating properties along the pathways between source and receptor. Threshold values (TVs) have been derived by taking into account of the natural background concentrations of naturally occurring substances in the groundwater body. TVs have been established so that they are no lower than the upper limit (95th percentile) of the natural background (baseline). The natural background concentration ranges have been determined through a research project to determine the natural quality of groundwater in England and Wales. These reports are published on the Environment Agency’s website. Threshold values were derived by taking into account the relevant criteria for protection of each receptor and groundwater body objective. For example, for the surface water test values were derived from surface water environmental quality standards, the drinking water protected area test thresholds were derived from drinking water standards. Achieving ‘good chemical status’ for groundwater involves meeting a series of conditions which are defined in Annex V of the WFD and in Articles 3 and 4 of the Groundwater Daughter Directive and applied to the groundwater body. Groundwater status objectives set by the WFD rely in part on the protection of, or objectives for, other associated waters and dependant ecosystems. The objectives for these must be known before groundwater classification can be fully completed. These associated waters and dependant ecosystems may have different sensitivities to water level and/or pollutants. As a result it is possible that different environmental standards may apply within a single groundwater body to reflect these varying sensitivities. There are five chemical status tests. Whilst the WFD emphasises the use of monitoring data during classification, in practice a weight of evidence approach, with monitoring data complemented by conceptual understanding and risk assessment data, is essential to ensure reliable classification of groundwater bodies and subsequent proper targeting of measures in the River Basin Planning process. The worst case classification from the five chemical tests is reported as the overall chemical status of the groundwater body. This is the one-out all-out system, as required by the WFD. If any one of the tests results in poor status, then the overall classification of the body will be poor. The confidence associated with the worst case test result is also reported. Achieving ‘good status’ for groundwater involves meeting a series of conditions which are defined in Annex V of the WFD and applied to the groundwater body. Groundwater status objectives set by the WFD rely in part on the protection of, or objectives for, other associated waters and dependant ecosystems. The objectives for these must be known before groundwater classification can be fully completed. These associated waters and dependant ecosystems may have different sensitivities to water levels, flow and/or pollutants. As a result it is possible that different environmental standards may apply within a single groundwater body to reflect these varying sensitivities. There are four quantitative status tests. Whilst the WFD emphasises the use of monitoring data during classification, in practice a weight of evidence approach, with monitoring data complemented by conceptual understanding and risk assessment data, is essential to ensure reliable classification of groundwater bodies and subsequent proper targeting of measures in the River Basin Planning process. The worst case classification from the four quantitative tests is reported as the overall quantitative status. This is the one-out all-out system, as required by the WFD. If any one of the tests results in poor status, then the overall classification of the body will be poor. The confidence associated with the worst case test result is also reported. To determine whether a GWB has a significant and sustained upward/downward trend, the results from the analysis of trends at individual monitoring sites have been assessed. Where a statistically significant trend is identified this trend must be tested for environmental significance. This assesses whether the trend is likely to lead to a failure of one or more environmental (status) objectives in the groundwater body. If one or more environmentally significant trends are identified, the GWB will reported as having a significant and sustained upward trend. Note: the presence of a statistically significant trend at an individual monitoring point does not on its own lead to a groundwater body having an upward trend. The trend must also be environmentally significant. The approach used follows EU CIS guidance. The trend assessment process is described further in UKTAG guidance: Groundwater Trend Assessment (http://www.wfduk.org/tag_guidance/Article_05/Folder.2004-02-16.5332/gw_trend) For the First River Basin Plan only upward trends have been reported. Success in achieving trend reversal will not be reported until the second River Basin Management Plans when the programmes of measures have had time to take effect. This is in accordance with CIS guidance. 75% used in all cases No relevant plumes identified There are no transboundary groundwaters in this RBD The pressures and impacts analysis for all groundwater bodies was reviewed in 2008 prior to carrying out groundwater body classification and trend assessment. As a result the risk assessments were updated using new and additional data. This has led to a general reduction in uncertainty and provided a sound base for classification and trend assessment. One area where significant progress was made was in assessing the risks to drinking water (DW) abstractions. No assessment was made in 2005 for DW and so this has marked a significant improvement in the groundwater risk assessment process. In addition each of the pressures and impacts (risk) assessments carried out has been linked directly to the status assessment/classification process. Further consultation with local experts has also been carried out to improve confidence in the risk assessments. Further Characterisation Reference http://www.environment-agency.gov.uk/research/planning/33268.aspx The conditions for good quantitative groundwater status are defined solely in the Water Framework Directive (2000/60/EC) and we have designed a series of tests for each of the elements defining good quantitative status, following CIS guidance (as noted below). There are four quantitative tests. Each test is applied independently and the results combined to give an overall assessment of groundwater body quantitative status. The worst case classification of the quantitative tests is reported as the overall quantitative status for the groundwater body. Groundwater bodies are classified as either at good or poor status. The classification process is described further in UKTAG guidance: Paper 11b(ii) : Groundwater Quantitative Classification for the purposes of the Water Framework Directive ( http://www.wfduk.org/tag_guidance/Article%20_11/POMEnvStds/gw_quantitative), and also in EU Water Framework Directive Common Implementation Strategy Guidance: Guidance Document No. 18: Guidance on Groundwater Status and Trend Assessment (http://circa.europa.eu/Public/irc/env/wfd/library?l=/framework_directive/guidance_documents/guidance_n18pdf/_EN_1.0_&a=d). The UK has undertaken classification in accordance with EU CIS guidance and applied a series of tests to determine chemical status. Each test addresses specific criteria/objectives for defining good status, as defined in the WFD. The tests consider overall impacts on the receptor not the impacts of individual pollutants. As a result, only one map showing groundwater body chemical status has been produced - as required by the WFD. Nitrate is a pollutant that is considered in several of the tests, along with other pollutants. It is therefore not reported separately. The UK has undertaken classification in accordance with EU CIS guidance and applied a series of tests to determine chemical status. Each test addresses specific criteria/objectives for defining good status, as defined in the WFD. The tests consider overall impacts on the receptor not the impacts of individual pollutants. As a result, only one map showing groundwater body chemical status has been produced - as required by the WFD. Individual pesticides (and total pesticides) are pollutants that are considered in several of the tests, along with other pollutants. They are therefore not reported separately. The achievement of good chemical status in groundwater involves meeting a series of conditions which are defined in the Water Framework Directive (2000/60/EC) and Groundwater (Daughter) Directive (2006/118/EC). We have designed a series of tests for each of the quality elements defining good chemical groundwater status, following CIS guidance, as noted below. There are five chemical tests. Each test is applied independently and the results combined to give an overall assessment of groundwater body chemical status. The worst case classification from the relevant chemical status tests is reported as the overall chemical status for the groundwater body. Groundwater bodies are classified as either at good or poor status. The classification process is described further in UKTAG guidance: Paper 11b(i): Groundwater Chemical Classification for the purposes of the Water Framework Directive and the Groundwater Daughter Directive (http://www.wfduk.org/LibraryPublicDocs/gw_chemical_classification_paper_final_draft), and also in EU Water Framework Directive Common Implementation Strategy Guidance: Guidance Document No. 18: Guidance on Groundwater Status and Trend Assessment (http://circa.europa.eu/Public/irc/env/wfd/library?l=/framework_directive/guidance_documents/guidance_n18pdf/_EN_1.0_&a=d). To determine whether a GWB has a significant and sustained upward/downward trend, the results from the analysis of trends at individual monitoring sites have been assessed. Where a statistically significant trend is identified this trend must be tested for environmental significance. This assesses whether the trend is likely to lead to a failure of one or more environmental (status) objectives in the groundwater body. If one or more environmentally significant trends are identified, the GWB will reported as having a significant and sustained upward trend. Note: the presence of a statistically significant trend at an individual monitoring point does not on its own lead to a groundwater body having an upward trend. The trend must also be environmentally significant. The approach used follows EU CIS guidance. The trend assessment process is described further in UKTAG guidance: Groundwater Trend Assessment (http://www.wfduk.org/tag_guidance/Article_05/Folder.2004-02-16.5332/gw_trend There are no transboundary groundwater bodies in this RBD Introduction In England and Wales point source pollution may result either from deliberate discharges to ground (e.g. treated sewage effluent), or accidental discharges (e.g. leakage of fuel from a storage tank). Deliberate discharges are generally adequately controlled through existing regulations e.g. the Environmental Permitting Regulations 2007 and the Groundwater Regulations 2009. Deliberate discharges are therefore unlikely to cause groundwater pollution. Accidental discharges, by their nature, are harder to control. We do however try to minimise the occurrence and impact of accidental discharges through pollution prevent campaigns (e.g. The Oil Care Campaign) and regulatory enforcement activity (e.g. serving Anti-Pollution Works Notices). A summary of the methodology is set out below. For further information please refer to ‘Environment Agency, River Basin Characterisation –RBC2, Groundwater – Overall Point Source Risk Document, Summary Assessment Method’. Methodology The assessment comprised two parts: 1) Consultation with EA area staff to identify significant point sources of pollution and classify them as ‘high’, ‘moderate’, or ‘low’ risk. 2) Identification of potential point sources of pollution from databases to classify groundwater bodies into ‘low’ and ‘no’ risk. For the identification of significant point sources of pollution EA staff provided details such as location and type of source, contaminants and degree of impact on receptors. The types of sources identified were generally closed landfill sites or those with a history of poor management. The significance of the impact from these sources was assessed against: a) Impact on dependent surface water body or terrestrial ecosystem; b) Groundwater abstraction data and exceedance of the UK drinking water standard (prior to treatment) c) Extent and degree of groundwater pollution. The threshold used was that the plume needed to exceed 1km in length (unless an alternative receptor was located nearer to the source). 17 sources were identified for assessment and 11 were assessed as ‘moderate’ or ‘high’ risk. For identification of potential point sources of pollution databases were analysed and the point sources including authorised discharges to ground, operational landfill sites or petrol stations, IPPC/PPC sites, groundwater pollution database mapped. A scoring system based on expert opinion was used to assess the potential risk of pollution. It took account of size and significance of pollution. The total density of scores for each groundwater body was calculated and a threshold determined to classify the sources into ‘low’ and ‘no risk’. The approach was limited by available data and also excluded some potential pollution sources e.g. contaminated land sites, scrap yards, and closed landfill sites. A confidence level was attached to the assessment depending on how good the evidence base was. The results were mapped onto the final combined ‘risk and confidence’ categories for reporting to Europe. Issues - The assessment only took into account current impacts on groundwater and did not consider mitigation measures to be implemented prior to 2015. - Time-lags of pollution to reach the receptor were not taken into account. - The focus has been on the size and location of sources that would potentially cause failure of a WFD environmental objective. Introduction The following 11 methods were used to assess diffuse source pollution pressures in our groundwater bodies (GWBs). For further information refer to EA WFD risk characterisation methods. Methodologies 1&2) Nutrient Nitrogen & Phosphorous For nitrogen the method took into account: a) Groundwater nitrate (N) vulnerable zone maps 2002&2007; b) Mapped groundwater vulnerability to N – based on N concentrations in soil drainage and vulnerability as a function of soil leaching potential, low permeability drift and aquifer type; and c) N concentrations in groundwater – based on historical mapped data and also the EA strategic monitoring network average concentrations and trends. The data were combined and mapped, and proportionality calculations assessed the risk according to each GWB. Worst risk categories were identified per GWB and a confidence category applied. The Phosphate (P) methodology took into account landuse and livestock at a 1km scale across England and Wales to calculate P loading. An exposure pressure map was drawn up to identify risk to surface water bodies (SWBs) using base flow index. Ground and surface water P monitoring data verified impacts and determined magnitudes. A risk category and confidence level were then applied. 3,4&5) Hazardous substances, Pesticides & veterinary medicines, Chlorinated Solvents 11 hazardous substances were assessed. The first step was to use data from the EAs groundwater monitoring network to calculate the mean concentration for each substance per GWB. If a GWB has less than 3 monitoring points it was excluded from the analysis. A pesticide risk model (POPPIE) was used to provide a risk map at 2km scale. Groundwater monitoring data was used to determine the impact from pesticide usage and sheep dip disposal data was also taken account of separately. For solvents a similar methodology was used as per hazardous substances above. All risks were classified individually for the three groups of substances above, and confidence levels applied. 6) Impacts on GWDTEs Relevant GWDTE were identified and a conceptual understanding of each set out. A scoring process to assess the chemical pressure risk was used. It took account of pollutants, hydraulic connection, and groundwater dependency. Individual risk scores were summed to give an overall risk per GWB. A risk category and confidence level were then applied. 7) Mines and Mine water discharge The data sources used for this method were EA expert judgement, mine locations and water quality information. Criteria used in the risk assessment included: a) Surface water quality risk b) Intrusion risk c) Rebound d) Mitigation e) Connectivity (mine to receiving WB) A risk category and confidence level were then applied. 8) Drinking Water Protected Areas Data from the Environment Agency’s monitoring programme and from Water Companies (WC) was compiled. A screening process checked for anomalies to make sure samples were representative. Trend analysis identified trends that were statistically significant. Results were extrapolated to predict mean concentration in 2012 and status and risk were determined per GWB. Correlation with WC data provided an indication of confidence. Any other additional trends identified from WC data were taken into account and also given ‘At Risk’ status. 9) Abstraction (Saline intrusion) Saline intrusion can inflow from saline coastal or connate water to the GWB if there is overabstraction. The intrusion risk assessment has been based on: a) the groundwater abstraction as a percentage of long-term average aquifer recharge and exposure pressure (taking into account the specific yield of the aquifer), and b) information from EA staff on observed intrusions. A risk category and confidence level were then applied. 10) Urban Areas For this risk assessment the % of urban cover above a GWB was used as an indirect indicator to identify GWBs at greatest risk. The method also takes into account low permeability drift to indicate the vulnerability of any underlying GWBs. Soil zone properties were not considered. Groundwater monitoring data were also used to indicate pollution. Risk categories were applied but a low confidence was attached to the assessment, unless monitoring data provided support. 11) Trends Assessment Data used: a) Groundwater Quality monitoring network data (10 years) b) WC Article 7 data which records evidence of upwards trends was used as supporting information (raw data was not available). Trend analysis was done for monitoring points with 10+ analyses over a period of >4 years. The data were reviewed and where trends were statistically significant results were extrapolated to predict concentrations in 2012, 2015 & 2021. Upward trends were checked for environmental significance. GWBs were then categorised. Introduction Four methods were used to assess four components of the groundwater abstraction and flow pressure in order for the groundwater bodies (GWBs) to be quantitatively characterised. The pressures for groundwater abstraction related to: 1) GWB resource balance (Water balance) 2) Deterioration of dependent surface water body (SWB) status 3) Significant damage to wetlands 4) Saline and other intrusions The methodologies are summarised below. For further information refer to the individual WFD risk characterisation methods as drafted by the EA http://www.environment-agency.gov.uk/research/planning/33332.aspx. Methodologies 1) Water Balance Test Using groundwater levels to characterise quantitative status of a groundwater body is problematic because they can fluctuate continuously. The characterisation was therefore based on ‘potential fully licensed’ and ‘recent actual’ pressure scenarios to determine the risk and associated level of confidence. The test has two parts: a) Compare the total abstracted groundwater to the long term average recharge of the GWB for both scenarios, b) Compare impacts of abstraction on low flows which is based on the flow screening values for all SWBs draining the GWB. Part b) of the test differs from SWB status test (2) because it is calculated at the larger groundwater body scale and ignores surface water abstractions and discharges. Issues raised: • Simplified estimates of recharge and abstraction rates were not refined for all GWBs • There is uncertainty around the relationship between flow and ecology in the development of the surface water flow screening values used in this assessment. 2) Deterioration of dependent SWB status If a significant part of the failure of SWB flow condition limit is attributable to groundwater abstractions, then the GWB upon which the abstractions and surface water flows depend, was flagged as being at risk of failing to achieve its groundwater quantitative status objectives. If this failure was based on the ‘recent actual’ abstraction and discharge scenario, then the supporting GWB was classified as at risk of failing quantitative status objective. If this failure was based on the ‘full licensed’ scenario, the GWB was assessed as being ‘at risk’ of failing its ‘no deterioration’ objective. At risk SWBs were identified where there was a current or future ‘deficit’ AND upstream groundwater abstraction impacts make up >50% of average low (natural) flows AND groundwater abstraction pressures within a sub-catchment could become 20% of the total upstream pressure. Risk and confidence levels of the results were based on these three criteria. Issues raised: • Those recorded in 1) above • Surface and ground water body dependence/boundary issues • Possible over-estimation of low flow impacts on SWB 3) Significant damage to wetlands This test considers the risks associated with groundwater abstraction impacting directly on a dependant wetland, not supported by a SWB. There were two stages of assessment: a) A significant damage risk assessment, b) Site specific analysis. NE and CCWales listed 1368 SSSIs they considered to be groundwater dependent terrestrial ecosystems (GWDTE). These sites were assessed using a source-pathway-receptor model and were assigned a cumulative risk score between 0 (no risk) and 9 (high risk). This used both GIS data and local expert opinion. The wetland risk results were mapped onto a GWB layer. The GWB’s were assigned risk scores based on (worst case) associated wetland risk. If there was no GWDTE associated, the GWB was assigned ‘Not at Risk’. Issues raised: • Not incorporating small scale and local drainage impacts, • Results may be an underestimation because of the screening in stage 1, • Localised impacts monitored can overestimate the spatial extent of risk • Lack of baseline data for some sites led to assumptions. 4) Saline or other intrusions Over abstraction can cause changes in groundwater flow direction. Intrusion can inflow from coastal or connate water in the GWB. The intrusion risk assessment has been based on: a) the groundwater abstraction as a percentage of long-term average aquifer recharge and exposure pressure (taking into account the specific yield of the aquifer), and b) information from EA staff on observed intrusions. The risk was then classified as ‘high’, ‘moderate’, ‘low’, or ‘no’ and a confidence level assigned depending on the breadth of evidence base. The results were mapped onto the final combined ‘risk and confidence’ categories for reporting to Europe. Notably, the assessment only took into account current impacts and not time-lag delays between abstraction and monitored intrusion. Furthermore, it did not take into account the extent and concentrations of intrusions. Not applicable Risk from Groundwater Intrusion was assessed under Diffuse Source Pollution and Groundwater Abstraction pressure methods. Please refer to the method text for these pressures. Not applicable The following risk categories causing an impact in groundwater bodies have been identified in the Western Wales RBD: • Diffuse Source Pollution - Drinking Water Protected Area risk • Diffuse Source Pollution - Mines • Diffuse Source Pollution - Nitrate • Diffuse Source Pollution - Pesticides • Diffuse Source Pollution - Saline intrusion • Diffuse Source Pollution - Terrestrial ecosystems • Water Abstraction and Flow regulation - Impact on surface water • Water Abstraction and Flow regulation - Overall Water Abstraction risk • Water Abstraction and Flow regulation - Saline intrusion (abstraction) • Water Abstraction and Flow regulation - Terrestrial ecosystems (abstraction) • Water Abstraction and Flow regulation - Water balance Impacts from identified pressures are described briefly in the following sections. Mines and Minewaters Minewaters are usually acidic (low pH) and the main contaminants are metals, for example copper, iron, manganese and zinc. Minewater may also contain priority substances such as cadmium and lead. These contaminants are released when oxygen in the air or water reacts with minerals in the rock found near coal seams and mineral veins. The metals are then dissolved in the groundwater which discharges back into surface water bodies, or by rain in the case of spoil. Pesticides Pesticide is a general term that includes all chemical and biological products used to kill or control pests. Due to their toxic nature they can cause harm to ‘non-target’ organisms and if they are not stored, used and disposed of properly they pose a risk to terrestrial and aquatic wildlife, of particular concern to GWBs is sheep dip. As well as ecological impacts, pesticides can also contaminate surface water and groundwater bodies used as drinking water sources, thus increasing the need for treatment. Urban and Transport Pressures Various pollution issues relate to the urban environment and transport networks. These include: • Urban drainage containing a variety of pollutants, • Air emissions from vehicles which are then deposited to water or land, • Run-off from air strips that may contain de-icers and pesticides to control weeds, • Leaching of pollutants from contaminated land. Abstraction and other artificial flow pressures Unsustainable abstraction from groundwater can lower groundwater levels and affect dependent river flows or wetlands, or can induce the intrusion of poorer quality water from the sea or from deeper aquifers. Flow in surface water bodies is a supporting element to biological classification for all classes other than High status, for which it is an obligatory consideration. Outflow from groundwater bodies contributes to the surface water flows required to support the biological classification. Unsustainable rates of abstraction reduce surface water flows and may result in lower flow velocities, reduced depths and reduced flow continuity that may limit ecological status. In addition, groundwater pumping may locally reduce spring flows and water levels important to retaining the ecological diversity and resilience of groundwater fed wetlands. Pressure from climate change is one of the pressing environmental challenges ahead especially the impact of climate change on river flows and groundwater in Wales. Flows are particularly vulnerable to climate change because they tend to rise and fall quickly in response to rainfall. The geology of Wales is such that there is relatively little natural storage of water in aquifers to support and maintain river flow in drier periods. Nitrates Nitrate pollution can impact on both surface water and groundwater and comes principally from agriculture (61%) and sewage treatment works discharges (32%) (England and Wales, Defra 2004). In urban areas the main inputs are from contaminated land, leaking sewers and water mains. The magnitude and balance of diffuse and point sources vary across river basin districts, as will the extent of inputs to surface and groundwater. High nitrate concentrations can impact on terrestrial ecosystems, such as wetlands, for example, through excessive nettle growth. Nitrate levels in groundwater are of particular significance to drinking water and there are controls on the amount of nitrate that is acceptable in drinking water. All groundwater bodies have been designed as Drinking Water Protected Areas. A significant and sustained increase in nitrate concentration in groundwater is seen in the Western Wales RBD.

Although significant progress has been made, there remain a number of data gaps and uncertainties in the pressures and impacts (risk) assessment process that will continue to be filled as we obtain more, and better, data. The most reliable data and knowledge exist for nutrient (nitrate) pressures and for pesticide pressures – these are considered to pose the greatest risk to groundwater. For other pollutants, whilst there is reasonable knowledge of pressures there is often only limited monitoring data to identify impacts. The linkages between pollutant sources and pressures, receptors and the effect on these receptors (changes in ecological status) is also not always well known. This reflects the complex nature of groundwater systems, the movement of groundwater and the behaviour of pollutants. In addition much of the data required to make the assessment is new and there is currently insufficient data in some areas to carry out a thorough and detailed risk assessment. On-going data gathering will continue to support the process and reduce uncertainty in the future. This will include better understanding of the groundwater systems as well as the impacts that pressures have on groundwater and associated surface waters and wetlands. The pressures and impacts analysis for all groundwater bodies was reviewed in 2008 prior to carrying out groundwater body classification and trend assessment. As a result the risk assessments were updated using new and additional data. This has led to a general reduction in uncertainty and provided a sound base for classification and trend assessment. One area where significant progress was made was in assessing the risks to drinking water (DW) abstractions. No assessment was made in 2005 for DW and so this has marked a significant improvement in the groundwater risk assessment process. In addition each of the pressures and impacts (risk) assessments carried out has been linked directly to the status assessment/classification process. Improved groundwater quality monitoring has been implemented. Investigations for both quantitative and chemical status are planned to better characterise the pollutant pathways and pressure linkages where risks have been identified. Research has been proposed to better understand the sources and behaviour of pollutants in the sub-surface and their impact on receptors, including the formulation of conceptual models for “at risk” groundwater bodies.

Background Details of the methodology used to determine where the exemption provisions of Article 4 (4-7) should apply in England and Wales (E&W) can be found in Annex E ‘Actions appraisal and justifying objectives’ for each of the RBMPs. The methodology used took into account CIS guidance on the use of exemptions (CIS Guidance Document no. 20). Extended deadlines and less stringent objectives (Articles 4.4 and 4.5) In E&W exemptions or alternative objectives have been identified for some WBs based on the conditions set out in Articles 4.4 and 4.5 of the WFD. These exemptions relate to the setting of an extended deadline or less stringent objective. These alternative objectives were determined through a process of measures appraisal and objective setting which included technical assessments (including consideration of technical infeasibility), economic assessment (to consider issues of disproportionate expense) and public consultation. In carrying out these processes, the programme of measures (see Annex C of RBMPs) was reviewed and, for each water body, modelling and/or expert judgement was used to predict the status that each element will achieve (and by when) once the measures are implemented. Checks were also made to ensure that the measures proposed for different pressures are compatible in terms of timing and benefits. If multiple pressures adversely affected WBs each pressure was individually assessed and then combined to identify the earliest date at which good status could be achieved. The predicted outcomes were translated to a set of overall objectives for each water body using the same ‘one out all out rules’ used in classification. Where any of the predicted outcomes for the elements of status were not ‘good status by 2015’, alternative objectives were set. Table 1 in Annex E lists the reasons (justifications) for setting alternative objectives (for full details please refer to Table 1). The three main reasons are Technically infeasible, Disproportionately expensive & Natural conditions. In identifying objectives, the best current available information was used. Initial focus has been on gathering information on WBs that can be improved by 2015. There is uncertainty in how pressures and technology will change after 2015. This could impact on WBs where an extended deadline has been set. Investigations (approximately 8,500 in E&W) are planned to help reduce this uncertainty and also current uncertainty about the cause of failures and feasible measures. Temporary deterioration (Article 4.6) In certain circumstances, as set out in Article 4.6, a temporary deterioration in status of a WB, caused by ‘exceptional or unforeseen’ events including prolonged droughts, extreme floods and accidents, is allowed. The exemption does not apply if these types of events could be planned for or prevented. Annex E of the RBMPs describes the Environment Agency’s management of drought and floods, including the triggers on which decisions are based. Accidents are detailed in relation to the Environmental Damage (Prevention and Remediation) (England or Wales) Regulations 2009 under the Liability Directive. Environmental damage has been defined as deterioration in overall WB status or a deterioration of status in any individual element/parameter (regardless of whether or not it causes deterioration in overall status). It is noted that WB classification will be done annually and therefore the methodology is unlikely to identify short term damage (i.e. lasting for period less than one year). The methodology also sets out remediation objective to return the WB to the status it was assessed at before the environmental damage occurred. New physical modifications and new sustainable human development activities (Article 4.7) No exemptions were applied to groundwaters under Article 4.7. General information The default objective is to obtain good status by 2015. If the predicted outcome for a WB is not ‘good status’ by 2015 alternative objectives have been set. For groundwater WBs the alternative objectives that have generally been set are those with extended deadlines. Where an objective has been set using an extended deadline, in the majority of cases this is ‘good status’ by 2027. Less stringent objectives have been set for five groundwater bodies in England and Wales. Detailed information Table 4 in Annex E (for each RBMP) lists the number of GWBs in the RBD where alternative objectives have been set. Annex B (for each RBMP) provides the status objectives for each WB. Overall status objectives are summarised in at RBD level. Information is also presented for each WB in individual tables, including the overall status objective (e.g. ‘Good by 2027’) plus the quantitative and chemical status objectives. Northumbria: Less stringent objectives have been set in 2 GWBs where there is currently no technical solution that can be applied to return the groundwater body to good status before 2027. The objective for these bodies, in relation to this problem, is to return them to good status as soon as is practically and technically possible. North West: Less stringent objectives are set in 3 GWBs where it would be either disproportionately costly or technically infeasible to achieve good status by 2027. None