Wastewater Permits in a TMDL World

1. Wastewater Permits in a TMDL World Katrina Kessler Marco Graziani.

2. Considerations • Legal Authority • Watershed Approach • Trifecta; Regulations, Schedules, and Backlogs • Reconciling Differences

3. Federal Water Pollution Control Act 1972 • NPDES program is born • Section 402 of CWA • Established maximum permit term of 5 years • Established TBELs and WQBELs • Provided for authority to delegate state programs • WQS and Implementation Plans are born • Section 303 of CWA • Directed states to implement WQS, identify impairments, and establish TMDLs

4. Effluent Limits 101 Restricts discharge of pollutants, expressed in terms of mass or concentration Technology based limits designed achieve “elimination of discharge of pollutants,” developed by analyzing data from similar discharges Water quality limits designed to achieve water quality standards in the receiving water, developed through analysis of effluent data along with ambient data

5. Effluent Limit Determination When TBEL doesn’t protect receiving water must develop a WQBEL Review discharge data, account for dilution in receiving water, determine if there is potential to exceed in-stream standard Limit applied if reasonable potential to cause or contribute to an exceedance of standard exists

6. Watershed Approach Highlights • Manage WQ using a 10-year cycle via major watersheds • Integrate biology, chemistry and physical/habitat monitoring • Integratecitizen and local partners • Identifyimpairments and waters in need of protection • Coordinate management efforts within a watershed • Track trends over time

7. 10 year Intensive Watershed Monitoring Schedule *

8. Rotating through the Major Watersheds Year 1 – 2 Monitor chemistry & biology Note potential priority mgmnt zones Assess WQ Develop 303(d) List Year 5 – 10 WLA into NPDES permits Award $ to local water partners Track BMP effectiveness Year 3-4 Stressor identification Set priority mgmnt zones Modeling TMDL and protection plans WQBEL? Every 10 Years 8

9. Regulations, Schedules, and Backlogs Required to issue permits on a 5 year schedule WQBEL required when discharges have “reasonable potential” TMDL is most comprehensive way to set WQBEL TMDLs done according to a different schedule Inherent conflict between 10 yr schedule and five year NPDES permit cycle Commitment to Minnesota citizens to use data collected during monitoring, modeling, and assessment work to inform permit decisions Commitment to EPA to keep backlog down Cannot delay permit issuance until TMDL completion

10. Permitting Ahead of TMDLs • Depth and breadth of data are accumulating • Assessment, stressor ID, modeling, and TMDLs take time • Need to develop WQBELs in advance of TMDLs • Effluent limit and permit staff are currently using data to set limits prior to assessment and TMDL process • Completed a pilot project in 2011

11. Watershed WQBELs • Develop WQBELs by watershed • Evaluate RP considering all sources, including non-point sources, within a watershed • Rely on land use data and models • Approach used to set WQBEL for 590 point sources upstream of Lake Pepin • Proposed approach for implementing river eutrophication standards • Would work for other conservative pollutants • Early coordination with TMDL staff is critical! • Assurance that assumptions will be honored

12. Pre-TMDL Outstanding Questions When is a site specific standard appropriate? What are the best tools to use to make valid point source and non-point source assumptions? How to insure that TMDLs will honor pre-TMDL modeling and assumptions? Does it make a difference if a TMDL is years off verses only a year or so in the future? How should TMDLs deal with discharges at a concentration < WQS?

13. Pre-TMDL Outstanding Questions • What about anti-backsliding? • If a TMDL WLA translates into a less restrictive WQBEL than what was included in a pre-TMDL permit, can a less restrictive limit be applied? • Yes according to… • 402(o)(2): new information (other than revised regulations, guidance or test methods) is available that was not available at the time of permit issuance which would have justified a less stringent effluent limitation • 402(o)(3): prohibits relaxation of effluent limitations in all cases if a revised limit would result in violation of WQS • 303(d)(4)(A): allows for establishment of less stringent WQBEL when receiving water is impaired if the permittee: 1) has a WQBEL based on a TMDL and 2) a relaxed WQBEL will result in attainment of WQS

14. Post-TMDL Outstanding Questions • What is the appropriate amount of detail to include in TMDLs related to WLA and implementation timelines? • Aggregate WLAs require much more work/time to implement into permits • If a TMDL includes an implementation timeline that sequentially spells out point source and non-point source reductions that can be helpful when developing permit conditions and schedules of compliance • What about situations when dischargers are not included in TMDLs?

15. Outstanding Questions • How do permits account for the time in takes to come into compliance with WQBEL? • Schedules of Compliance (SOC) • SOC require compliance with WQBEL ASAP • ASAP may extend beyond projected TMDL date, can’t simply buy for time for completion • Completed TMDL implementation plan may define ASAP • Anticipated changes to a WQBEL cannot be considered in SOC • What if ASAP is not as soon as reasonable? • Logistics of public notice/public participation of watershed based WQBEL