1. Mercury TMDL Review & Permitting Strategy Update
Jeff Poupart
Water Quality Permitting Section Chief
Division of Water Resources

2. Mercury TMDL Review Background
Mercury affects nerve cells in the brain and spinal cord
Persistent in environment, bioaccumulative
NC DHHS statewide fish consumption advisory for largemouth bass
Not just a NC problem
Atmospheric deposition significant mercury source

3. Mercury TMDL Review Total Maximum Daily Load
Section 303(d) of Federal Clean Water Act
NC Statewide Mercury TMDL
Approved by EMC - September 13, 2012
Wastewater Permitting Strategy also approved by EMC
Approved by EPA - October 12, 2012

4. Mercury TMDL Review NC statewide mercury TMDL
2002 = baseline year
TMDL target = 0.3 mg/kg mercury in fish tissue
12 ng/l is aquatic life criterion, not human health
67% reduction in total mercury loading needed
Wastewater sources have met reduction
NC air sources expected to meet by 2016

5. Mercury TMDL Review In NC
Atmospheric deposition = 98%, wastewater = 2%
In-state air ≈ 16%, out-of-state air ≈ 84%
TMDL provides statewide aggregate load for mercury in wastewater = 81 lbs/year
TMDL + permitting strategy ensure mercury contributions from wastewater remain low

6. Permitting Strategy Update
Strategy Components
Monitoring
“Reasonable potential” analysis
Water quality-based limits
Mercury Minimization Plans
Technology-based maximum – 47 ng/l

7. Permitting Strategy Update
How and who gets limits, MMPs
Look for effluent sampling values >47ng/L
Look for average sampling >12ng/L, taking upstream into account
If neither, monitoring only
Perform Reasonable Potential Analysis
Based on Instream Waste Concentration of discharge into river
Facilities that do receive a limit will be phased approach first 4 yrs of 5 yr permit

8. Permitting Strategy Update
Mercury Minimization Plans
Best Management Practice
Acceptable alternative to WQBELS in most cases
Preferable to very low facility-specific permit limits
Template developed in stakeholder process
Customizable, flexible
Low administrative burden – results every 5 years
Other states require MMPs for smaller facilities

9. Permitting Strategy Update
Mercury Minimization Plans for >2MGD
Look for values>Practical Quantitation Level (PQL)
Mercury is tested using EPA Method 1631E
PQL ~0.5ng/L
Permitting strategy requires MMP whenever there is “consistent detectable” mercury
MMP also required if permitee had a limit for mercury

10. Permitting Strategy Update
Since January 2013 DWR has issued 444 permits
80 Majors/364 Minors (57 w/ permitted flow >2 MGD)
41 permits with Mercury Minimization Plan required
37 w/ permitted flow >2 MGD
46 w/ mercury limits or monitoring
19 Majors/27 Minors (13 w/ permitted flow >2 MGD)
34 w/ monitoring requirement
12 w/ permit limits

11. Permitting Strategy Update
Impact on wastewater permits
Less frequent monitoring
Fewer facilities with limits
More mercury minimization plans
Lower costs overall
Why?
TMDL documents source contributions
TMDL provides statewide allocation for wastewater

12. Questions. Permitting: jeff. poupart@ncdenr. gov TMDL: kathy
Questions? Permitting: TMDL: