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2008-2010 Surface Water Standards Triennial Review and Implementation Connie Brower Nikki Remington-Julie Grzyb-Sandra Moore NC Division of Water Quality
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Triennial Review The State is obligated under the federal “Clean Water Act” to review surface water quality standards every three years
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Clean Water Act Requirements Limit the amount of pollutants that can be present in surface waters Outline conditions of the surface water that will ensure protection of the designated uses Protection must include physical, chemical and biological integrity of the waters
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Anticipated Major Changes: Triennial Review (2008-2010) Chlorophyll a Aquatic life metals standards 2,4 D standard (Water Supply only) Clarifications and reorganization of Red Book regulations
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Chlorophyll a Current “max not to exceed” language modified to “not greater than 10 percent of data shall exceed” Proposed change reflects DWQ’s current interpretation of the chlorophyll a standards 303(d) listing purposes Addition of a regional standard for mountains and upper piedmont 25 ug/L
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Mountain and Upper Piedmont Waters Per 2B.0202: all of the waters of the Hiwassee; Little Tennessee, including the Savannah River drainage area; French Broad; Broad; New; and Watauga River Basins; and those portions of the Catawba River Basin above Lookout Shoals Dam and the Yadkin River Basin above the junction of the Forsyth, Yadkin, and Davie County lines.
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Review of National Criteria and Science Since 1980’s - US EPA has published revisions to many metals To date, North Carolina has not adopted those recommended changes Proposed revisions to metals standards reflect the most current science
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Metals Toxicity Toxicity of metals is influenced by many factors such as…. Form and speciation of metal pH, TSS, DOC, TOC, etc… EPA’s national criteria take some of these factors into account Dissolved metals Hardness based criteria with equations
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Dissolved Metals Current standards are “total” metals Dissolved metals better represent the bioavailable fraction Dissolved fraction varies in natural waters With the exception of Mercury and Selenium, DWQ has proposed the use of dissolved metals standards
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Dissolved Metal Standards Implementation Upon permit renewal, once adopted, new criteria for metals will be used to calculate limits Permits are, have and must be written as total metals per 40 CFR 122.45 (c)
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Hardness Dependent Metals For some metals: ↓ water hardness is associated with ↑ aquatic toxicity ↓ water hardness is associated with ↑ aquatic toxicity Proposed numerical standards are based upon a default hardness of 25 mg/L Metal specific formulas are also proposed to allow more localized applications of proposed standards
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Metals Standards Implementation Some metals standards are hardness dependent NPDES permits must incorporate protective concentrations that consider instream water hardness Applicable in-stream hardness for use with metals equations: – –10th percentile of local 8 digit HUC
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10 th Percentile Hardness by 8-Digit HUC Hardness Data: 1969-2001 843 stations 37,530 samples
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8-Digit HUC Hardness
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Metal Current Total Aquatic Life Standard (ug/L) Proposed Dissolved Freshwater Standard (ug/L) Chronic 50 mg/L Hardness Chronic 25 mg/L Acute 25 mg/L Arsenic50150340 Beryllium6.5 65 Cadmium*2 / 0.4 trout0.150.82 / 0.51 trout Chromium (total)50Proposed for removal Chromium III *none24180 Chromium VInone1116 Copper *7 (AL)2.7 (AL)3.6 (AL) Iron1 mg/L (AL)Proposed for removal Lead *250.5414 Nickel *8816140 Silver *0.06 (AL) 0.30 (AL) Zinc *50 (AL)36 (AL)
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Stakeholder Concerns Goals Today – Provide links with guidelines to help answer questions for your permitted facility Who will likely receive permit limits and / or additional monitoring ? How can I calculate these predicted permit limits? How can I assess the economic impact of the proposed dissolved metal standards?
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User Guide
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Located under NPDES Wastewater website – Quick Links User Guide and Permit Limit Calculators to assist Permittees in understanding how the proposed Surface Water Standards (dissolved metals) will impact NPDES Permit Limits http://portal.ncdenr.org/web/wq/swp/ps/npdes Permit Limit Calculators
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Calculator 1 Estimates the Total Recoverable Metal Permit Limits for dissolved metals standards Uses: – –Proposed default hardness of 25 mg/L – –NPDES Permitted Flow (MGD) – –Receiving stream’s summer 7Q10 (cfs) Calculator 1 should provide conservative permit limit estimates for each facility because it uses the lowest hardness proposed under the revised regulations
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Calculator 2 Also estimates Total Recoverable Metal Permit Limits for dissolved metals using: – –Combined hardness of permittee's 8- digit HUC hardness and the facility's effluent hardness, a mass balance approach – –A default hardness of 25 mg/L is used if the mass balance of the combined hardness data is less than 25 mg/L
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Implementation: Hardness Determination For Stream hardness – –Use 10th percentile hardness of 8-Digit HUC For Effluent hardness – –Permittee data, NPDES will use the 10 th percentile of monthly effluent hardness values over a 1-2 year period. – –NPDES will request permittees to submit once/month sampling data with application for renewal. – –If no effluent hardness data, use 25 mg/L default value
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What is my facility’s applicable hardness? To Determine a Permittee’s receiving stream’s allowable dissolved metal concentration use the following Hardness mass balance equation: (H in-stream, mg/L * 7Q10, MGD) + (H effluent, mg/L * Plant flow, MGD) (7Q10, MGD + Plant flow, MGD) Mass balance hardness less than 25 mg/L? Use default of 25 mg/L Mass balance hardness greater than 400 mg/L? Upper bound = 400 mg/L
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CALCULATOR 2 0.4310.431.040.0
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To assess impact, complete Calculator 1 or 2 …. Observe current permit limits and estimated permit limits; gather laboratory metals data If effluent data equals or exceeds the estimated Permit Limits, assume limits & monitoring will be added to facility's next permit renewal If, for the last 5 years, all the effluent sampling data shows the metal as “less than the PQL” and the estimated permit limit is greater than the PQL, it is not likely a limit/monitoring will be placed in the NPDES permit
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Remember to …. Examine Pre-treatment Impacts (if applicable) Staff have prepared information to assist you! http://portal.ncdenr.org/web/wq/swp/ps/pret Contact Deborah Gore or Dana Folley 919- 807-6383 or 807 - 6311
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Fiscal Impact NC General Statutes require an assessment of fiscal impact when regulations are modified Fiscal Note must be completed and APPROVED by Office of State Budget Management (OSBM) prior to formal public comment period and public hearings
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Fiscal Impact DWQ mailed out requests for information on costs and benefits related to these proposals Monday, June 7 th Deadline for submission of costs/benefits is Tuesday, September 7 th From these documents, NC DWQ will draft a State required Fiscal Note for approval by OSBM Public Comment period will begin after this Fiscal Note is completed and approved
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Timelines January/March 2010 – EMC granted our request to proceed to Notice of Public Hearings June 7, 2010- websites available to assist permit holders http://portal.ncdenr.org/web/wq/swp/ps/npdes http://portal.ncdenr.org/web/wq/swp/ps/npdes September 7 th – End of timeframe to submit fiscal information to DWQ for inclusion in OSBM Fiscal Note Fall 2010: Staff develops OSBM Fiscal Note Spring 2011 ?: Public Hearings announced…
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Contacts Connie Brower connie.brower@ncdenr.gov 919-807-6416 Nikki Remington 919-807-6413 Julie Grzyb 919-807-6389
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Links to Website http://portal.ncdenr.org/web/wq/home http://portal.ncdenr.org/web/wq/ps/csu/swtr irev http://portal.ncdenr.org/web/wq/swp/ps/np des http://portal.ncdenr.org/web/wq/swp/ps/pret
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Hardness Dependent Equations Metals criteria are expressed as formulas Example: Chronic Standard for Copper.960 * e^0.8545[ln(hardness)]-1.702 Source: NRWQC
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Dissolved Standard Implementation A Translator is required to convert from dissolved metal standard to a total metal permit limit Translator answers the question: "What fraction of metal in the effluent will be dissolved in the receiving water?"
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