Draft Field-Based Methods for Developing Aquatic Life Criteria for Specific Conductivity
EPA has published a draft document, Field‑Based Methods for Developing Aquatic Life Criteria for Specific Conductivity. Elevated water salinity, as measured by conductivity, has been shown to negatively affect aquatic life in freshwaters. Elevated conductivity is associated with multiple sources, including discharge from wastewater treatment facilities, surface mining, oil and gas exploration, runoff from urban areas, and discharge of agricultural irrigation return waters.
The draft methods provide flexible approaches for developing science-based conductivity criteria for flowing waters that reflect ecoregional- or state-specific factors. Once final, states and authorized tribes located in any region of the country may use the methods to develop field-based conductivity criteria for flowing waters. This draft document provides a scientific assessment of ecological effects and is not a regulation. EPA is accepting public comments until February 21, 2017 on the draft document.
- Fact Sheet (December 2016)
- Federal Register Notice: Draft Field-Based Methods for Developing Aquatic Life Criteria for Specific Conductivity (December 23, 2016)
- Public Review Draft: Field-Based Methods for Developing Aquatic Life Criteria for Specific Conductivity (December 2016)
- Appendix A: Case Study I Supporting Materials
- Appendix B: Case Study II Supporting Materials
- Appendix C: Example Case for Estimation of Background Specific Conductivity
- Appendix D: Development of a Background-to-Criterion Regression Model for Geographic Applicability
- Appendix E: Combined Data Set for Case Studies I and II
- Appendix F: Case Example Using an Alternative Measure of Exposure ([HCO3− + SO42−])
- Appendix G: Case Example Using an Alternative Assessment Endpoint (Species of Fish)
- Field Data Sets Used in the Draft Document (zip)(1 pg, 15 MB)
- External Peer Review