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Connie Brower NC DENR Division of Water Resources.

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Presentation on theme: "Connie Brower NC DENR Division of Water Resources."— Presentation transcript:

1 Connie Brower NC DENR Division of Water Resources

2 Triennial Review of Standards  For the US EPA to approve modifications to a state’s standards, criteria must be sufficient to maintain protection of human health and aquatic life  The Triennial Review is toxicity based

3 Proposed Changes:  Human Health standards  Aquatic life metals standards  Clarifications/reorganization of water quality standards regulations

4 2,4 D: chlorophenoxy herbicide Incorporation of updated non-cancer information provided through US EPA IRIS

5 Manganese The current water quality standard for Manganese is proposed to be removed from the regulations Naturally occurring levels of Manganese in North Carolina waters are elevated

6 Proposed Changes to Aquatic Life Standards

7 Review of National Criteria and Science Since 1980’s - US EPA has published revisions to several metals To date, North Carolina has not adopted those recommended changes Metals standards are proposed for modification to reflect current science 15A NCAC 02B.0211 and.0220

8 Aquatic Life Standards Acute Criterion  For Metals:  Acute standards are proposed (along w chronic)  Exceptions: Selenium & Mercury (chronic only)  Duration information is proposed  96 hour average - chronic  1 hour average - acute

9 Flow Design Criterion  1Q10 flow criterion for implementation of the acute standards  Flow design based upon federal guidance  Currently in use by NPDES permit writers (daily max)

10 Metals Toxicity  Toxicity of metals is influenced by factors such as….  Form and speciation of the metal  pH, TSS, DOC, TOC, water hardness, etc…  EPA’s national criteria take some of these factors into account  Dissolved metals  Hardness-based criteria with equations  Cu Biotic Ligand Model (10 co-parameters)

11 Dissolved Metals  With the exception of Mercury and Selenium, DWR proposes the use of dissolved metals water quality standards  Dissolved metals standards better represent the bioavailable fraction

12 Hardness-Dependent Metals  For some metals: ↓ water hardness is associated with ↑ aquatic toxicity  Metal specific equations that include provisions for localized hardness applications are proposed

13 Hardness-Dependent Metals Equation-based instream standards are proposed Formula for Cadmium (chronic): {1.101672-[ln hardness](0.041838)} ∙ e^{0.7998[ln hardness]-4.4451} Numerical instream standards illustrated using a hardness of 25 mg/l are presented in proposed rules for clarification purposes Applicable Cadmium (chronic) illustrated standard at an instream hardness of 25 mg/l (or lower) = 0.15 ug/l

14 Flexibility of Applicable Instream Hardness Values The ability to use applicable instream hardness concentrations between 25 mg/l to 400 mg/l To assess compliance with the equation based standard, hardness is sampled with metals analysis

15 Dissolved Metal Standards: Implementation in Ambient Monitoring Collect instream sample for metal & hardness analysis Filter in field (to capture the dissolved portion) Routine metals analysis by laboratory Enter lab reported hardness into the equation(s) from 2B rules to calculate each metal standard Compare reported dissolved metals instream concentration to the sample specific metal standard to determine compliance.

16 Dissolved Metal Standards Implementation in NPDES permits 40 CFR 122.45 (c): permits are written as total recoverable metals NPDES will employ EPA published translators for this purpose Translator answers the question: What fraction of metal in the effluent will be dissolved in the receiving water?

17 Hardness-Dependent Metals NPDES Implementation Permits will incorporate protective metals levels that consider in-stream and effluent water hardness In-stream hardness for NPDES use: Median percentile of local 8 digit HUC data Effluent hardness for NPDES use: Median percentile of effluent hardness data

18 Metal Current Total Freshwater Aquatic Life Standard Proposed Dissolved Standard at 25 mg/l hardness (ug/L) Chronic at 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 Manganese** current WS std**Proposed for removal Nickel *8816140 Silver0.06 (AL) 0.30 (AL) * Zinc *50 (AL)36 (AL)

19 Biological Confirmation Assessment of the biological integrity of the stream will supersede instream metal sampling results when determining attainment of aquatic life use Exceptions: Mercury and Selenium

20 Variances In accordance with 15A NCAC 02B.0226 – variances from the state water quality standards may be approved by the Commission on a case-by-case basis. Comments received with respect to the applicable variances will be forwarded to the Surface Water Protection Section for evaluation during the next permit cycle review

21 Fiscal Impact (NC GS 150B)  Fiscal impacts detailed  Fiscal analysis prepared & submitted to Office of State Budget Management (OSBM)  OSBM has certified that proposed rules & fiscal note meets the requirements of NC GS 150B-19.1  Alternatives considered:  No action  Adoption of revised Total vs Dissolved Metals

22 Fiscal Impacts  Projected outcomes (~2950 permittees):  ~96% wastewater dischargers not affected  ~106 facilities get new limits for metal(s)  ~21 facilities revert to monitoring only  Estimated impact:  $181 m in costs over 30 year period, Net Present Value  $195 m in benefits over 30 year period, Net Present Value

23 Projected Timeline  November 19, 2013 Public Hearing  January 3, 2014 End of Comment Period  March 13, 2014 Hearing Officer’s Report  March–April 2014 Complete Fiscal Note Draft proposed regulations  May 2014WQC review of proposals Request approval for Public Hearings **** Request to proceed to EMC  Summer 2014Public Hearings  Fall / Early winter 2015 EMC approval request

24 Request to Proceed to EMC to Ask for Permission to Proceed to Public Hearing with Surface Water Quality Standards Rule Amendments to 15A NCAC 02B and Approval of the Fiscal Note in accordance with NC GS 150B-19.1(e). (WQC may request a “30-day waiver” to proceed to EMC the next day)

25 Questions? Connie Brower Classifications and Standards/ Rules Review Branch Connie.Brower@ncdenr.gov 919-807-6416 http://portal.ncdenr.org/web/wq/ps/csu/swtrirev


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