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South Eastern River Basin District - Environmental Quality Standard Development-
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Classification
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Biological An assessment of the biological quality elements must be taken into account when assigning waterbodies to any of the ecological status or ecological potential classes. The status of each of the biological elements for natural waterbodies is determined by measuring the extent of the deviation, if any, from the reference condition of a particular waterbody. Reference conditions are the conditions of the biological elements in the absence of pollution or disturbance.
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Biological- EQR The Ecological quality ratios (EQR) scale for the monitoring system for each surface water category is divided into the five classes (High, Good, Moderate, Poor and Bad) by assigning a numerical value to each of the boundaries between the classes. The values for the boundary between the classes of high and good status, and between good and moderate status are being established through the EU supported intercalibration exercise.
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Biological Calculating an Ecological Quality Ratio (EQR) The biological quality elements grouping comprises four specific elements as follows: phytoplankton macrophytes invertebrates fish
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Biological For each of these elements the Directive prescribes a number of parameters
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Classification WFD classification systems and environmental quality standards (EQS) were developed by the Environmental Protection Agency for the purpose of assessing the ecological status of surface waters in Ireland using these suites of quality elements. EQSs were developed by the EPA for the following elements: general components (physico-chemical) quality elements are as specified in WFD Annex VIII (10 – 12), e.g. dissolved oxygen, nutrients and temperature specific relevant pollutants are those identified by Member States as being discharged in significant quantities; this is also specified in WFD Annex VIII (1 - 9), e.g. metals Chemical Status-Priority substances are specified in WFD Annex X these EQSs have been developed by the Commission.
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Classification For the general components (physico-chemical) the WFD requires, for the purpose of classification, the setting of EQS values for the high/good and good/moderate boundaries where applicable. For the specific relevant pollutants the directive requires the setting of a single EQS for each pollutant. Failure to achieve either one of these standards will mean failure to achieve good ecological status and thus good surface water status. Chemical Status- priority substances the directive requires a single standard that will separate the two chemical status classes: “good” and “failing to achieve good” set out in the Directive
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Classification- Overall “ONE OUT ALL OUT PRINCIPLE” In the classification of the ecological status/potential for surface waters, the Directive requires that the lowest status assigned to either the biological quality element, general components (physico-chemical), and hydromorphological elements or failure to achieve the standards set for the specific relevant pollutant will determine the ecological status that can be assigned to the water body. For chemical status failure to achieve any of the standards set for each of the substances will result in that waterbody failing the test for chemical status.
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General Components
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EQS Development- UK TAG Methodology The development of EQSs in Ireland is based on the same methodology as the UKTAG. This process took thousands of sites of “good” biological data and looked at a summary statistic of the relating physico chemical data. The value which was achieved by 90% of the sites was picked as the standard. The choice of the 10% point allows for the inevitability that some of the sites chosen as good biological quality maybe slightly poorer than good.
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UK TAG methodology- Irish Context Link together the Physico- Chemical monitoring data and Q data Identify the biological conditions associated with high and good status »High- Q4-5/Q5 »Good- Q4 Abstract all the good sites and the associated physico-chemical monitoring data. Identify and calculate the summary statistic. Identify the value achieved by 90% of the sites.
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General Components- EQS Development
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General Components- EQS Development- Terminology According to the WFD an Environmental Quality Standard (EQS) is “the concentration …(over a given time)… of a particular pollutant or group of pollutants in water, sediment or biota which should not be exceeded in order to protect human health and the environment.” A Trigger Action Value (TAV) specifies a parallel, more stringent target for environmental quality for certain parameters. A Trigger Action Value (TAV) is a concept developed for establishing Irish standards and will be used at national level in Ireland. The TAV will be used to prevent deterioration of Irish waters by triggering management actions before status failures occur. An EQS specifies the absolute compliance concentration or range for a water quality element in the environment. Failure of a general component EQS will classify the waters as failing to achieve the WFD’s ecological status objective
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Temperature The maximum temperature for which a Trigger Action Value (TAV) of 21.5˚C is proposed in all waters, is based on the Imperative Standards set for the support and protection of salmonid fish in the Salmonid Regulations. The proposed Environmental Quality Standard (EQS) limit of 1.5ºC rise above ambient temperature outside of the mixing zone in all waters is also based on salmonid standards adopted in the Salmonid Regulations.
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DO Rivers and Lakes For rivers and lakes a minimum daytime Dissolved Oxygen (DO) Trigger Action Value (TAV) of 9 mg/l is proposed. This limit links with the Salmonid Regulations standard and is supported by statistical analysis of Irish datasets. A maximum daytime Trigger Action Value (TAV) for rivers and lakes of 11 mg/l is proposed as an indication of supersaturation conditions. This action value range applies to surface grab samples collected during the daytime. If this range is not complied with an assessment must be carried out and if deemed necessary then 24 hour DO measurements must taken. The existing Salmonid Regulations standard of 7mg/l recorded over a 24 hour period is proposed as a minimum environmental quality standard (EQS) for Dissolved Oxygen.
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DO Transitional and Coastal A DO standard for coastal and transitional waters has been proposed in line with those percent saturation values currently adopted in the EPA’s Assessment of (TSAS) for coastal and transitional waters. As with the freshwater standard a lower limit (5%ile) and a super saturation limit (95%ile) have been proposed. Statistical analysis of unpolluted marine sites showed that the values adopted by TSAS represented appropriate EQSs values.
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BOD For rivers, statistical analysis identified a Trigger Action Value (TAV) of less than 2mg/l as annual median. If this annual median TAV is not complied with investigation and, where appropriate, follow-up action must take place to address the source of the elevated BOD. A maximum Environmental Quality Standard (EQS) of less than 5mg/l in rivers is also based on statistical analysis and links to the value of 5mg/l set in the Salmonid regulations. This EQS is an absolute maximum with a site failing WFD status objectives if any single sample is recorded above 5mg/l. A TAV of less than 4mg/l is proposed as a 95%ile of recorded samples, this is in line with values adopted by the EPA in their water quality management plans. An EQS of less than 5mg/l is proposed as a 98%ile of recorded samples in estuaries, this value is derived from the statistical analysis of unpolluted site data and ties in with values proposed for rivers and the Salmonid Regulations.
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pH pH ranges have been proposed for both hard and soft waters to identify natural acidification conditions in rivers and lakes. This was determined by linking the pH and alkalinity data with summary maximum and minimum statistics extracted for hard and soft water sites
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Ammonium The proposed EQSs are based on the statistical analysis. The data supported the development of separate standards for ammonium concentrations at high and at good status sites. The EQSs relates to annual median of readings at a river site.
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DIN The TAV of 2.6mg/l for the freshwater end of an estuary is derived from the EPA’s Trophic Status Assessment Scheme (TSAS) criterion for DIN, this has been shown to link to changes in biological status and is supported by statistical analysis of all unpolluted sites. The TSAS value of 0.25 mg/l DIN also has been proposed as a TAV for the outer (high salinity) part of an estuary. Values for DIN are shown in both mg/l and μM units to reflect the different units currently used in coastal and transitional monitoring programmes. The concentrations range between 2.6mg/l - 0.25mg/l is equivalent to ≈185μM - 18μM.
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MRP The proposed annual median EQSs for MRP of 34 µg P/l and 50 µg P/l in rivers for high/good and good/moderate boundaries respectively are based on statistical analysis. The more stringent proposed river annual median TAVs of 16 µg P/l and 30 µg P/l MRP for high/good and good/moderate boundaries respectively have also been derived statistically. The TAVs represent the levels that half of the sites (50% of the samples) achieve and are consistent with the standards in the Irish Phosphorus Regulations. Breach of the parallel (more stringent) TAV, in line with the existing Phosphorus Regulations, necessitates action at Member State level to investigate the cause of and take measures to prevent a failure of the EQS. The proposed EQS is set at an absolute status failure limit with any breach being reported to the European Commission
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Specific Relevant Pollutants
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Specific Relevant Pollutants were included for EQS development in Ireland for the following reasons: Substances from the Irish Dangerous Substances Directive which were not included on the WFD Priority Substances list. General inorganic and organic chemicals for which EQSs have been developed by UK TAG Pesticides for which EQSs have been developed by UK TAG Substances which were showing in the screening monitoring programme
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Specific Relevant Pollutants In this study international regulatory bodies have been relevant ecotoxicological datasets that have been collated by national and evaluated along with data from the peer reviewed literature. Technical reports were developed by WRc for each standard. These reports were also reviewed by a Peer review group consisting of Irish Ecotoxicologists.
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Specific Relevant Pollutants The following 11 Specific Relevant Pollutants in the ROI have new proposed standards Chromium Cypermethrin 2,4-D Diazinon Dimethoate Linuron Mecoprop Phenol Glyphosate Mancozeb Monochlorobenzene
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Specific Relevant Pollutants It was agreed to retain the S.I. 12 of 2001 standards for the following standards 7 parameters: Arsenic Copper Cyanide Fluoride Toluene Xylenes Zinc Fluoride, Toluene and Xylene the new proposals were less stringent than the current standards under the DS directive Arsenic, Copper, Cyanide and Zinc there was a lack of adequate data to produce robust new standards. Further work will be done at a later date on these metals.
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