Agenda

1. Whole Effluent Toxicity Sublethal Limitations Workgroup January 19, 2010(please sign in and include an email address)

2. Agenda • Welcome • Purpose and Introductions • Workgroup Ground rules • EPA Sublethal Requirement • General Updates • What are other States doing? • Topics to discuss in subsequent meetings

3. Purpose of Workgroup • To discuss how the Division will incorporate numeric sublethal WET limitations in permits. • Timing – • Short timeframe, and therefore the purpose of these meetings will be to briefly discuss topics and collect ideas • Identified Topics • 1) When sublethal limits may be evaluated; 2) how RP may be determined; 3) what a sublethal limit will look like; 4) what happens if the limit is violated

4. WG Goals & Groundrules • Workgroup Goals http://projects.ch2m.com/cwqf/Workgroups/guidlines.pdf • open discussion on key issues and topics with goal of obtaining consensus where possible, and/or understanding of issues where disagreement remains • Workgroup Chair – Andrew Neuhart (WQCD) • Workgroup Coordinator – Nancy Keller (Pueblo) • Email list – Please sign up • Information and Documents posted on WQ Forum Website – Workgroups - WET

5. WG Goals & Groundrules • Groundrules • Come to each meeting prepared for the scheduled discussion, e.g. having reviewed any relevant draft documents that have been circulated prior to the meeting. • Speak up so that everyone can hear. Only one person should speak at a time. • Be concise in asking questions and/or stating your perspective on an issue. • Avoid personal attacks. Be respectful of others’ perspectives and responsibilities.

6. WG Goals & Groundrules • Groundrules • Look for similarities that may exist in spite of differences. Listen carefully to the perspectives/ proposals raised by others and respond in a manner that moves the discussion forward. • Clearly identify remaining differences that are not resolved by work group discussions. • Avoid sneak attacks. Respect the process by letting others know of positions and actions that will be taken regarding the issues being discussed.

7. Agenda • Introductions • Who • Representing • EPA Statement of Chronic Toxicity Requirement – as stated in September 2009 meeting by EPA headquarters

8. General Updates • Ensure the new WET Policy includes/matches the requirements from the following documents: • Short-term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms, Fourth Edition, October 2002 • Methods for Measuring the Acute Toxicity of Effluents and Receiving Waters to Freshwater and Marine Organisms, Fifth Edition, October 2002 • USEPA. 1991a. Technical support document for water quality-based toxics control. Office of Water. Washington, DC. EPA/505/2-90-001. • EPA Region 9, 10 (and 8) Toxicity Training Tool.

9. General Updates Updated references through the new policy Potential to remove the chronic lethality endpoint or change from IC25 to an LC (available in ICIS: 50 or 10) Potential removal of Statistical Difference endpt Addition of how to request ATP Potential to identify the dilution ratios Merge/Elimination of Biomonitoring Guidance and Laboratory Guidelines for WET (Mar 98) into one policy (by reference to EPA docs)

10. Current WET Limits At this time Colorado permit WET limits are based on lethality to the test species (acute as an LC50 > 100% effluent, or chronic as IC25 “as defined by lethality”, at the IWC). Growth and reproduction are report only conditions, measured as part of the chronic test procedure.

11. Future WET Limits • Inclusion of numeric limitations for chronic sublethal effects. • How do we get there? • Determine when to include sublethal limits • Identify criteria for RP • Determine what the limitations will look like • Determine compliance/enforcement response to failed sublethal tests

12. What are Other States Doing?

13. What are Other States Doing?

14. Topic Identification Item 1 • When are sublethal limitations considered ? • EPA TSD – 100:1 or less dilution, site specific between 100:1 and 1000:1 dilution • Colorado – currently 10:1 or less (with exemptions) • Topics • What should the chronic dilution criteria be? • Exemptions? • Or should it be considered for all discharges or a subset there of? • Multiple determinations – dilution ratio, aquatic life class or expectations, type of pollutants, others?

15. Topic Identification Item 2 • How to Determine RP? • EPA – quantitative based on TU’s • Colorado – qualitative based on major/minor, pollutant evaluation, quantitative if data available • Topics • Qualitative vs Quantitative (need to go to TU’s or direct comparison with IWC + margin of safety) • Multiple lines of evidence – automatic if exceedance • New facilities or facilities without data • Requiring test results with renewal applications

16. Topic Identification Item 3 • What will a limit look like? • EPA – acute LC50 at 100% effluent, chronic IC25 with dilution • Colorado – acute LC50 at 100%, chronic lethality IC25 (as expressed by lethality) AND Stat Diff at the IWC (need to fail both), report sublethal • Topics • TU or IWC • continue with dual endpoints? (is stat diff similar to NOEC/LOEC or a comparison between replicates?) • Mixing zones?

17. Topic Identification Item 4 • What if a violation occurs? • EPA – accelerated testing – 6 tests, if 1 fails move to PTI/TIE, potential TRE • Colorado – accelerated testing 2 in a row or 3 of 5, move to PTI/TIE, potential TRE • Topics • Auto compliance schedule, PTI/TIE, TRE • Compliance Unit response, ERG

18. Next Meeting • February 9th – 9:30 to 12:30 – CDPHE • When do we look at sublethal. • How should RP be determined. • Additional ideas or follow up information due by January 25th (allow for time to add to agenda and ensure documents posted to Forum website)