Water: Water Quality Standards Academy
Preparation for Deriving the CMC: Assessing Acute Effects Data
- Listing Impaired Waters and Developing TMDLs
- Monitoring & Assessment
- NPDES Permit Program
- Human Health Ambient Water Quality Criteria
- Aquatic Life Criteria
- EPA's Role
- Two Concentration-Related Criteria
- Steps in Deriving the Criteria
- Prioritizing Chemicals
- Collecting Effects Data
- Assessing Acute Effects Data
- Calculate the GMAVs
- Rank the GMAVs
- Calculate the FAV
- From FAV to CMC
- Factoring in Water Characteristics
- CCC Approach Based on Available Data
- Assessing Chronic Effects Data
- CCC Calculation of the FCV
- FCV to CCC
- Criteria Review Process
- Site-Specific Criteria
Basic Course: Supplemental Topics
Assessing the quality and completeness of collected data includes screening the data for validity based on such criteria as:
- Use of a control.
- Use of a single species and compound for each test.
- Use of species from North America.
- Use of flow-through tests if the compound is volatile or easily degrades.
- Reporting of water characteristics (e.g., hardness or pH) when relevant to toxicity.
All valid toxicity data are used in ALC development, since confidence in a criterion usually increases along with the amount of acceptable data. A three-step calculation process results in a Final Acute Value, which is then used to derive the Criterion Maximum Concentration. These FAV calculation steps are listed below and described on the next several pages of the module.
- Calculate the Genus Mean Acute Values.
- Rank the Genus Mean Acute Values.
- Calculate the Final Acute Value.
Illustration. View graphic showing overview of ALC derivation. Proceed to the Illustration. » (Note: This link launches a pop-up window.)