Mercury Method 1631: It’s Not As Bad As We Thought It Would Be Dana Folley, PERCS Unit 2005 NC Pretreatment Workshop August 23, 2005 Charlotte, NC

Mercury Sources Natural Sources - volcanoes, forest fires, soils Manmade Sources - coal-fired power plants, incinerators, manufacturing, dental amalgam WWTP –sewer pipe slime bio-accumulates Hg, releases Hg when slough off –Sediments accumulate Hg, heavy flow sends Hg to WWTP –WWTP equipment with mercury – bearings, switches - seals fail Mercury crosses state, regional, global boundaries

Minamata Disease Japan 1956

Minamata Memorial MAYBE DELETE??

EPA Saves Snowball in Vegas (2004)! Waynesville – 10/04 1/2 cup spilled, cleaning lady to hospital, house decon- taminated Asheboro – 2005 resident collects periodic table elements - 39 lbs, plus!

North Carolina Fish Consumption Advice Issued in April 2002 Advises restricted consumption of largemouth bass, chain pickerel, bowfin caught from NC waters Establishes range of south and east of I-85

Water Bodies on 303(d) List for Mercury 303(d) list to EPA of impaired NC waters - based on actual fish tissue analysis –Entire Lumber River Basin –Roanoke River (Va portion too?) –Parts of Neuse River main stem (NEW) –Albemarle Sound –Atlantic Ocean - for King Mackerel only –7 other creeks, rivers, and lakes in the Cape Fear, Roanoke, Pasquotank, White Oak and Yadkin Basins

Water Quality Standards - Water NC WQS: –Aquatic Life (Freshwater chronic): 12 ng/l (0.012 ug/l) –Aquatic Life (Saltwater chronic): 25 ng/l Great Lakes WQS: –Human Health:1.8 ng/l –Wildlife:1.3 ng/l EPA Criteria –Aquatic Life (Freshwater acute):1,400 ng/l –Aquatic Life (Freshwater chronic): 770 ng/l Drinking Water Standard - 2,000 ng/l NC Groundwater WQS – 1,100 ng/l

Water Quality Criteria- Fish Tissue EPA Human Health Criterion: –0.3 mg Methyl Hg/kg fish NC DHHS Fish Advisory: –0.4 mg Total-Hg/kg fish Compare to Japan 1956 Minamata Exposure: –Residents consumed fish with 20 mg methyl mercury per kg of fish during several meals per week for years How to convert fish tissue criteria to water column criteria?

EPA Method Why use it?

EPA Method Clean Sampling

NC Method 1631 Requirements Based on EPA agreement, DWQ required Method 1631 for effluent sampling at applicable NPDES facilities beginning September 1, –Current or potential NPDES limit is 200 ng/l or below (see mercury limit calculator on PERCS mercury webpage) –And –Mercury is pollutant of concern (on NPDES limits page, pretreatment program, or major municipal)

Method DMR Effluent 1631 Results NEEDS A LOT OF WORK TO BRING UP TO DATE First Year Results - 96% of effluent samples below the WQS (<12 ng/l). Why such good results? –Clean sampling, pretreatment, pollutant removal, etc.

NC Mercury NPDES Permitting Requirements Mercury limit now expressed as Weekly Average Class III and IV WWTPs - Weekly effluent Class I and II WWTPs -Twice per month effluent For new limits, propose compliance schedule to allow for source evaluation, budgeting, etc.

NC NPDES Permitting for Non-Impaired Waters WWTP Receiving Waterbody is not Hg-impaired i.e, not on 303(d) list Calculate NPDES limit in normal fashion, taking into account dilution at 10 year drought stream flow (7Q10) Perform normal Reasonable Potential Analysis (RPA) with 7Q10 dilution If “reasonable potential” exists for WWTP to violate limit, add limit and Compliance Schedule

NC NPDES Permitting for Hg-Impaired Waters WWTP Receiving Waterbody is Hg-impaired and on 303(d) list EPA assumes upstream is already at NC WQS, so do not allow 7Q10 dilution NPDES limit will be equal to NCWQS = 12 ng/l Perform Reasonable Potential Analysis (RPA) with NO dilution If “reasonable potential” exists for WWTP to violate limit, add limit and Compliance Schedule Facility can collect upstream samples to test assumption.

NC NPDES Permitting for Hg- Impaired Waters with TMDLs Current TMDLs (Lumber, Cashie) have shown point sources to be minimal contributor to mercury load. TMDL can be expressed in NPDES permits as a mass load limit (eg. grams/day) or require implementation of a Pollution Prevention (P2) strategy. PERCS and Division of Pollution Prevention and Environmental Assistance (DPPEA) currently preparing P2 language.

NC NPDES Compliance For those with limits already, generic SOC with P2 requirement is being developed for any non-compliant facilities. Regions continue with civil penalty discretion.

NC NPDES Discharge Monitoring Reports (DMRs) Enter mercury data in same units as are on NPDES limits page. Enter all effluent mercury data, even LTMP/STMP.

NPDES Compliance - Pretreatment Remember MSDSs don’t tell you about inactive ingredients or contaminants. What if mercury is in ambient or raw water supplies? –Drinking Water Standard - 2,000 ng/l –NC Groundwater WQS – 1,100 ng/l If Mercury is everywhere, what good will slapping “zero” limits on a few “big bad SIUs” do? Dentists!!!!!!

Method 1631 and Pretreatment Requirements NC DWQ PERCS will only require 1631 for other locations (Influent, Uncontrollable, SIU, etc.) if there is a problem at your effluent, i.e., you are having significant limits violations December 18, 2002 PERCS webpage

Method 1631 and Pretreatment Of the few Pretreatment POTWs that had been having detections above 200 ng/l using 245.1, most are NOT having any hits any where near 200 ng/l with 1631 and 1669!!!!!!! 24 HWAs using 1631 for effluent, 9 also using 1631 influent –18 approved, 6 more in house

Method 1631 and Pretreatment ave of ave range of ave Influent –Only –only Effluent – 0.68 –Max individual effluent 102.4

Method 1631 and Pretreatment ave of ave range of ave Removal Rate96%87% - 99% MAHL triples or quadruples 5 without tertiary filters – no real difference

Method 1631 and Pretreatment Uncontrollable ave of ave range of ave Sampling Mass balance – 470 EPA Literature 300

NC Water Quality Standard (WSQ) Current NC WQS adopted in 1989 based on EPA’s 1988 Water Quality Criteria EPA’s new (January 2001) Ambient Water Quality Criteria is expressed as 0.3 mg/kg methyl mercury in fish tissue Need Bio-accumulation Factors (BAFs) to translate WQC into total mercury surface water quality target/standard EPA Guidance on this still not out

NC Eastern Regional Mercury Study (ERMS) Gather NC specific stream and fish tissue data needed to calculate BAFs and perform translation Implemented Nov 2002-Aug 2003 Final Report on web-site next year Mercury Study Extension – covers the French Broad to the Pasquotank

ERMS Target water column levels to protect human health (fish consumption) Goal 3a: Target water levels

ERMS Measured Total Mercury in WWTP effluentMAYBE NOT USE if DMR sum shows same Goal 4: Mercury in effluent

DWQ Water Quality Standard Using Method 1631, NC Mercury WQS will be exceeded in surface waters in some cases. Appears existing WQS is not protective of consumption of largemouth bass except for smaller fish, and even then not in all cases. Although recommended by EPA, BAF approach assumes relationship between mercury fish tissue and mercury (or methyl mercury) in water column is linear. This may not be true. Need EPA WQC Implementation Guidance

And now for the big picture…

Mercury Questions? All s are PERCS - Pretreatment: ?????????, NC DWQ, PERCS Unit (919) ext. ???, – –NC DWQ Mercury 1631 letters (NPDES - 8/30/02 and 8/1303; Pretreatment 12/18/02) –Mercury NPDES limit calculator –Method 1631 and 1669 (clean sampling) documents –Presentations, guidance, and links

Mercury Questions? NPDES: Tom Belnick, NC DWQ, Point Source Branch (919) ext. 543 – NC DWQ Laboratory (919) –Metals Unit Roy Byrd, Lead Chemist, ext DWQ 1631 lab up and running!!! –Laboratory Certification Unit James Meyer, Supervisor, ext

Mercury Questions? ERMS/TMDL/303(D) List: Michelle Woolfolk, NC DWQ, Modeling&TMDL Unit (919) ext. 505 – WQS: Connie Brower,NC DWQ Standards Unit (919) ext. 380, – Fish Advisories: Luanne Williams, NC Dept Health and Human Services (919)

Mercury Questions? Biological Assessment (Fish tissue) –Mark Hale, Planning - Basinwide Plans – Ambient & Coalition Monitoring –

Mercury - Summary Mercury can be bad in the environment and to human health, especially as Methyl mercury Incidents of Mercury Contamination are still occurring Some NC waters have fish exceeding health criteria, DHSS issued fish consumption advice notices for half of NC

Mercury - Summary Most NC NPDES facilities below NC WQS –Those in significant violation can get P2 SOCs NPDES Civil Penalty Discretion Continues New/Renewal NPDES Limits will be weekly averages New NPDES Limits will include compliance schedule TMDL Limits may be expressed as P2 schedules

Mercury – Summary (continued) Method 1631 works well on WWTP influent, uncontrollable, and SIUs WWTP site-specific 1631 removal rates much higher than EPA Literature Site-specific 1631 Uncontrollable within range of EPA literature DWQ PERCS may adopt NC literature removal rate and uncontrollable

Mercury – Summary (continued) DWQ continues to study NC site- specific mercury water body conditions and basis for NC WQS

Questions?