Post-Construction Compliance Monitoring

1. Adrienne Nemura LimnoTech National Perspectives, Developments, and Advanced Wet Weather Solutions Workshop April 22-24, 2009 Chicago, IL Post-Construction Compliance Monitoring

2. Take-away Messages Draft your Phase II permit language before you propose a post-construction monitoring program Agree on the minimum requirements for compliance Do not incorporate LTCP or the �program� by reference Do not accept conditions/limits that you cannot meet Remember: each CSO situation is site-specific

3. Background (1) The CSO Policy applies to EPA and the NPDES program Regulatory agencies should put xyz in permits Language about the post-construction compliance monitoring/assessment is not specific Developed before EPA�s guidance on ambient monitoring

4. Background (2) EPA�s NPDES regulations require effluent monitoring & reporting EPA�s guidance on ambient monitoring for eligible dischargers Encourages permit writers to offer incentive of reduced effluent monitoring in exchange for discharger doing ambient monitoring Supports watershed approach Case-by-case consideration for intermittent discharges

5. CSO Policy: LTCP Section 9. Post-Construction Compliance Monitoring Program The selected CSO controls should include a post-construction water quality monitoring program adequate to verify compliance with water quality standards and protection of designated uses as well as to ascertain the effectiveness of CSO controls. This water quality compliance monitoring program should include a plan to be approved by the NPDES authority that details the monitoring protocols to be followed, including the necessary effluent and ambient monitoring and, where appropriate, other monitoring protocols such as biological assessments, whole effluent toxicity testing, and sediment sampling.

6. Monitoring to Develop a LTCP Monitor and model for system characterization CSO flow and effluent quality Receiving water flow and quality Characterization of other sources (sometimes) Model the effectiveness of CSO controls to decide which controls are appropriate Model to show (or presume) that CSO control will comply with water quality standards Use of continuous models preferred for assessing intermittent, highly variable discharges

7. Issues for Proposing a Post-Construction Compliance Monitoring Program �verify compliance with water quality standards� Wasn�t the monitoring & modeling for the LTCP sufficient to do this? �ascertain effectiveness of CSO controls� Apply collection system model to evaluate performance of CSO controls or monitor the discharges �plan to be approved by the NPDES authority� Are effluent and ambient monitoring necessary? If biological assessments, WET testing, and sediment sampling weren�t needed to select controls�

8. CSO Policy: Phase II Permit Section 2. Phase II Permits--Requirements for Implementation of a Long-Term CSO Control Plan d. A requirement to implement, with an established schedule, the approved post-construction water quality assessment program including requirements to monitor and collect sufficient information to demonstrate compliance with WQS and protection of designated uses as well as to determine the effectiveness of CSO controls.

9. Issues for a Phase II Permit (1) Similar language only different Is it an �assessment� program or a �monitoring� program? Are CSO controls working as designed? Are the remaining CSOs causing WQ standards violations? Policy includes a �plan� but does not discuss implementation of the plan Does not define how data are to be used for developing effluent limits

10. Issues for a Phase II Permit (2) �demonstrate compliance with WQS� Didn�t we do that in the LTCP? Permits are supposed to contain WQBELs (not ambient monitoring) �ascertain the effectiveness of CSO controls� Metrics used to select CSO controls are typically related to frequency and volume of CSO discharged Permit writer has to define what is required to �ascertain effectiveness� of implementation of LTCP Discharger may need to take the lead on developing language that can be met

11. Recap: CSO Phases of Permitting Phase 1 � NMCs and Develop LTCP Phase 2 � NMCs, Implement LTCP, comply with WQBELs (meaning, compliance with performance standards of the selected CSO controls to achieve WQ goals) Phase 3 � Comply with WQBELs Difference between �compliance monitoring program� and �compliance with permit limits�

12. Take-away Messages Draft your Phase II permit language before you propose a post-construction monitoring program Agree on the minimum requirements for compliance Do not incorporate LTCP or the �program� by reference Do not accept conditions/limits that you cannot meet Remember: each CSO situation is site-specific

13. Questions? Adrienne Nemura Vice President LimnoTech 501 Avis Drive Ann Arbor, MI 48105 Tel. 734-332-1200 anemura@limno.com

14. References EPA (1996). U.S. EPA NPDES Permit Writer�s Manual. www.epa.gov/npdes/pubs/owm0243.pdf (pdfp. 156) EPA (1995). CSOs: Guidance for Permit Writers. cfpub.epa.gov/npdes/cso/guidedocs.cfm (p. 4-30 & 5-2) EPA (1995). CSOs: Guidance for Long-Term Control Plan. cfpub.epa.gov/npdes/cso/guidedocs.cfm (p. 4-15) EPA (1999). CSOs: Guidance for Monitoring and Modeling. www.epa.gov/npdes/pubs/sewer.pdf (p. 2-11) EPA (1996). Interim Guidance for Performance-Based Reductions of NPDES Permit Monitoring Frequencies. www.epa.gov/npdes/pubs/perf-red.pdf