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Mixing Zones

A “mixing zone” is an area in a water body surrounding, or downstream of, a pollution discharge where the effluent plume is diluted by the receiving water. Put simply, mixing zones create sacrifice areas that violate Clean Water Act standards designed to protect water bodies and their designated uses (such as fishing and swimming), and embrace the long-discounted notion that “dilution is the solution to pollution.” Mixing zones are a primary reason why the congressional goal to end pollution discharges to our nation’s waters by 1985 has not been achieved.

Mixing zoneA “mixing zone” is an area in a water body surrounding, or downstream of, a pollution discharge where the effluent plume is diluted by the receiving water. Mixing zones undermine the Clean Water Act’s (CWA) purpose “to restore, and maintain the chemical, physical, and biological integrity of the nation’s waters,” by allowing pollutant discharges into sensitive waterways that harm aquatic life, particularly anadromous fish stocks. Put simply, mixing zones create sacrifice areas that violate Clean Water Act standards designed to protect water bodies and their designated uses (such as fishing and swimming), and embrace the long-discounted notion that “dilution is the solution to pollution.”  Mixing zones are a primary reason why the congressional goal to end pollution discharges to our nation’s waters by 1985 has not been achieved.

Background

Mixing zones are nothing new, and in fact, are implemented in nearly every state in the nation.  However, Congress never even mentioned the term “mixing zones” when it passed the Clean Water Act in 1972.  But over time, industry lawyers and municipal governments concocted this legal fiction that now dominates most large discharges throughout Alaska and beyond.  In the Cook Inlet, the present mixing zone policy threatens not only the fish, shellfish and whales that require clean water and healthy habitats, but also the countless Alaskan families who rely on sport, commercial, personal use and subsistence fishing.  The largest mixing zone discharges in Cook Inlet come from municipal sewage and the oil and gas industry.

Oil and Gas Dumping in Cook Inlet

Cook Inlet is the only coastal water body in the United States where EPA allows the oil and gas industry to dump toxic drilling and production wastes into important subsistence, commercial, and recreational fisheries. On May 27, 2007, the EPA approved the General Permit for the discharge of pollutants from oil and gas facilities in federal and state waters located in Cook Inlet, Alaska. The permit increased the amount of toxic dumping in Cook Inlet, and allows the oil industry to discharge approximately 100,000 gallons of oil and over 835,000 pounds of toxic metals each year.

On October 21, 2010, the Ninth Circuit Court of Appeals issued an unpublished decision which left in place the Clean Water Act permit that allows the oil and gas industry to virtually triple the amount of toxic pollution it dumps annually into Cook Inlet fisheries. Cook Inletkeeper et al v. U.S. Environmental Protection Agency, No. 07-72420, (9th Cir. October 21, 2010). Cook Inletkeeper, along with a coalition of fishing and Alaska Native groups responded sharply to the court opinion: “Chevron has raked in over $10 billion in profits so far this year, yet they refuse to properly treat the toxic waste they dump into our subsistence fisheries,” said Tom Evans, an Alaska Native and a member of the Nanwalek IRA Council in Lower Cook Inlet. “This is a human rights issue – our elders and our kids have a right to clean water and healthy fisheries.”

At the heart of the matter are nationwide standards called Effluent Limitation Guidelines – or ELGs – which define the best available technology for oil and gas industry waste treatment in the nation’s coastal and offshore waters.  These standards recognize that zero discharge is the best available technology for every coastal water body in the country, EXCEPT Cook Inlet.  EPA’s rationale for excluding Cook Inlet from the same rules found elsewhere rests on assumptions about technology, industry activity, and economic feasibility.  Yet since EPA promulgated the ELG’s in 2006, these assumptions have all changed. Today, the conditions strongly favor stricter standards for toxic industry waste.  Cook Inletkeeper and others are now actively pursuing changes to the ELGs to bring Cook Inlet into line with the rest of the nation.

Exemption for Spawning Streams

Salmon splashing in creek.As March 2014, mixing zones are not allowed in salmon spawning areas, including lakes, streams, rivers, “or other flowing fresh waters” (exceptions are allowed if spawning commences after the pollution discharge has been authorized – i.e. if anadromous fish move into a stream that was categorized as “non-spawning” the year before, those fish are not protected).

In 2004, Governor Frank Murkowski spearheaded a regulation change that was slated for implementation in 2006 for mixing zones, which loosened the requirements in spawning streams. The change would remove a prohibition against mixing zones in grayling, northern pike, whitefish, salmon, and other fish spawning areas and created exceptions to the spawning streams off-limits rule. This has not taken place, however, because the EPA in Region 10 has not approved the 2006 rule change.  In 2007, Alaska Representatives Paul Seaton, Les Gara, and Gabriele LeDoux put forth a bill (HB 74) that sought to ban mixing zones in spawning streams. Unfortunately, this bill did not pass. Protection of Cook Inlet and all of Alaska’s water requires a similar citizen initiative, with regulatory state-wide, scientifically-based water quality and mixing zone standards. These standards must recognize these water bodies as sensitive ecosystems upon which residents depend for their livelihood.  The standards should place water quality above the special interests that influence and ignore regulations, and lessen the quality of life for Alaskans.

Mixing Zones Do Not Meet the Objectives of the Clean Water Act and the EPA

The Clean Water Act neither officially recognizes, nor prohibits, mixing zones. “[W]henever…the discharges of pollutants from a point source…would interfere with the attainment or maintenance of that water quality…which shall assure protection of public health, public water supplies, agricultural and industrial uses, and the protection and propagation of a balanced population of shellfish, fish, and wildlife, and allow recreational activities in and on the water, effluent limitations…shall be established which can reasonably be expected to contribute to the attainment or maintenance of such water quality.” (CWA 33 U.S.C. §1312(a))

The EPA has included mixing zones within their regulatory framework, but it is part of an implementation policy and not a substantive regulation. In other words, the regulations promulgated by the EPA permit the states, rather than the federal government, to regulate mixing zones at their discretion. (40 CFR Section 131.13.) The EPA also guides states to craft a policy that ensures mixing zones:

The vague nature of this approach has permitted the intrusion of pollution into important salmon spawning areas, directly contrary to the clear intent of the Clean Water Act. Instead, the EPA should honor the intent of the Clean Water Act, and require pollution discharges to meet applicable standards at the end of the discharge.  If mixing zones are allowed, they should be a rarity, with a high bar to show there's no way to properly treat the waste.  As always, these issues only happen with citizen involvement and pressure on legislators. Until then, mixing zones will continue to allow large volumes of pollution to Alaskan waters, with little regard for the impacts they cause.

Additional Sources:

EPA Mixing Zones Standards and Guidance

The Mixing Zone Manual Or How to Stop the Dilution-Solution... (Earth Island Institute)

AK Mixing Zones Guidance Documents:

AK Department of Environmental Conservation (2009)

NOAA (2004)

Progressive Alaska: Look at HB74, Permit State Approved to Triple Dump Loads, etc.

Protect Wild Fish from Pollution Initiative

Mixing Zone Application

NMFS ESA S. 7 Consultation for Mixing Zones and Their Effect on Belugas

AK Minerals Commission on Mixing Zones

Evaluation of Effects of Permit Reauthorization on Endangered Species