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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. Triennial Review.
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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
Triennial Review The State is obligated under the federal “Clean Water Act” to review surface water quality standards every three years
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
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
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 standardfor mountains and upper piedmont • 25 ug/L
Mountainand 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.
Review of National Criteria and Science • Since 1980’s - US EPAhas published revisions to many metals • To date, North Carolina has notadopted those recommended changes • Proposed revisions to metals standards reflect the most current science
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
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
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)
Hardness Dependent Metals • For some metals: ↓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
Metals Standards Implementation • Some metalsstandards 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
10th Percentile Hardness by 8-Digit HUC Hardness Data: 1969-2001 843 stations 37,530 samples
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?
Permit Limit Calculators 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
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
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
Implementation: Hardness Determination For Stream hardness Use 10th percentile hardness of 8-Digit HUC For Effluent hardness Permittee data, NPDES will use the 10th 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
What is my facility’s applicable hardness? To Determine a Permittee’s receiving stream’s allowable dissolved metal concentration use the following Hardness mass balanceequation: (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
CALCULATOR 2 0.43 10.4 31.0 40.0
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,allthe effluent sampling data shows the metal as “less than the PQL”and the estimated permit limit isgreater than the PQL, it is not likely a limit/monitoring will be placed in the NPDES permit
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
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
Fiscal Impact DWQ mailed out requests for information on costs and benefits related to these proposals Monday, June 7th Deadline for submission of costs/benefits is Tuesday, September 7th From these documents, NC DWQ will draft a State required Fiscal Note for approval by OSBM Public Comment periodwill begin afterthis Fiscal Note is completed and approved
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 • September 7th – 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…
Contacts Connie Brower connie.brower@ncdenr.gov 919-807-6416 Nikki Remington 919-807-6413 Julie Grzyb 919-807-6389
Links to Website http://portal.ncdenr.org/web/wq/home http://portal.ncdenr.org/web/wq/ps/csu/swtrirev http://portal.ncdenr.org/web/wq/swp/ps/npdes http://portal.ncdenr.org/web/wq/swp/ps/pret
Hardness Dependent Equations • Metals criteria are expressed as formulas • Example: Chronic Standard for Copper .960 *e^0.8545[ln(hardness)]-1.702 Source: NRWQC
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?"