Every three years, the Alaska Department of Environmental Conservation (ADEC) conducts a comprehensive review of the Water Quality Standards (WQS) in 18 AAC 70. This review helps to keep the pollution limits for Alaska's waters up to date by integrating the latest science, technology, policy, and federal requirements into how the State regulates water quality.

2021-2023 Triennial Review

Questions submitted during 2021-2023 Public Notice Period

Question: Regarding the Fish Consumption Rate, you’ve already formed a work group and sought public input, you’ve already reviewed this topic on previous Triennial Reviews. What happens now? What will it take for DEC to adjust the Fish Consumption Rate to a realistic number in this state? When can we expect it to be adjusted?

Answer: DEC Leadership is reviewing the Human Health Criteria Workgroup Report and associated documents. DEC has not established a timeline as to when it may take action on the DEC fish consumption rate and updates to state water quality standards at 18 AAC 70.

Question: There was talk recently of revising the mixing zone regulations. Does this have anything to do with EPA’s attempt to change mixing zones to allow them in anadromous salmon streams? If not, what’s the reason for revisiting Alaska’s mixing zone rule?

Answer: The language in the TR Issue Summary is referring to Zones of Initial Dilution (ZIDs). In certain cases discharges utilize diffuser technology which creates rapid and complete mixing in a very brief period of time and space in a receiving water. Under federal guidance– a discharger could be issued a dilution allowance rather than a mixing zone. DEC is exploring whether having explicit language that references ZIDs and dilution allowances. There is no proposal to modify any other aspects of the existing language at 18 AAC 70.240 at this time.

Question: Will existing Tier 3 water nominations be reviewed for designation through this Triennial Review process? If not, why not? Similarly, if a new Tier 3 water nomination were to be put forward through this Triennial Review process, would it be reviewed by DEC for designation? If not, why not?

Answer: See the DEC guidance pertaining to the nomination of Tier 3 waters. In short, if someone was to nominate a water as Tier 3 during the 2021-2023 TR, that nomination would be noted in the Response to Comments summary with the following response (Policy and Procedure Number 05.03.104 (2018))

EPA Submission Documents

• pending

Public Notice

• Public Notice Triennial Review 2021-2023 (PDF)

Proposed 2021-2023 Triennial Review Issues

• Proposed 2021-2023 Triennial Review Issues

Fact Sheets

• Triennial Review Temperature Fact Sheet
• Triennial Review Process (PDF)
• Human Health Criteria in Alaska Water Quality Standards (PDF)

Archived Fact Sheets

Archived Documents

Contact Info

• Brock Tabor
• Environmental Program Specialist
• Alaska Department of Environmental Conservation
• Division of Water
• Water Quality Standards, Assessment & Restoration
• Telephone 907-465-5185
• Email brock.tabor@alaska.gov