Welcome to the Mixing Zone

by Gershon Cohen
Campaign to Safeguard America's Waters (C-SAW)

In September of 1998, Earth Island launched the Campaign to Safeguard America's Waters (C-SAW) to stop the authorization of mixing zones (pollution-dilution zones) in federal wastewater discharge permits.

Polluters save money by using mixing zones to legalize the dumping of pesticides, herbicides, and other industrial contaminants into our lakes, rivers and coastal waters. Instead of applying established water quality standards at the point of discharge, state and federal regulators use mixing zones to increase pollution allowances based on the volume of the receiving water. Meanwhile, the vast majority of the public remains unaware that millions of gallons of toxic substances are being watered down every day into "legal" discharges within mixing zones that may extend from a few feet in length to miles downstream from the point of discharge. Mixing zones make waters unsafe to drink, unfit to play in, and incapable of supporting aquatic life. (See EIJ Winter/ Spring 1998 for more background on the mixing-zone loophole in the Clean Water Act.)

Over the past year, C-SAW has turned up the heat on the mixing-zone issue by (1) providing technical and strategic support to local organizations challenging specific pollution discharge permits that contain mixing zones; and (2) initiating an attack on the underlying principles of mixing zone authorization.

Muck in Montana
The Smurfit/Stone pulp mill releases wastes into the Clark Fork River, directly from outfall pipes and indirectly as groundwater seepage from the mill's 800 acres of treatment ponds. The mill's permit allows it to exceed all six of Montana's effluent parameters: Biological Oxygen Demand(BOD), Total Nitrogen, Total Phosphorus, Total Suspended Solids (TSS), Color and Temperature and therefore further degrade the Clark Fork's ability to support aquatic life. Under Montana regulations, Smurfit's discharge of wastes into habitat that is protected for drinking and fish harvesting is legal - because it has been given a mixing zone in the Clark Fork that is 9 miles long.

According to Tony Tweedale of Montana's Coalition for Health, Environment, and Ecological Right), "the coffee-colored plume hugs the shoreline for miles beyond the mill site and treatment ponds." Geoff Smith of the Clark Fork-Pend Oreille Coalition adds, "the downstream edge of the mixing zone was chosen because of its convenience as a testing location, not because of any concern for water quality."

Pollution in Puerto Rico
Activists in Puerto Rico are fighting seven mixing zones - six from antiquated sewage treatment plants that also release polluted wastes from nearby industrial facilities.

According to Sarah Peisch of Centro Accion de Ambiental, "the outfalls only meet primary treatment standards - 70 percent of the solids remain in the effluent. Many of the discharges and their mixing zones are adjacent to critical coral reef and fish habitat, less than a mile offshore from major recreational areas enjoyed by thousands of residents and visitors to Puerto Rico's beaches."

The group also is fighting a proposed mixing zone at a Gulf Oil refinery in San Juan Bay that would include a laundry list of toxic wastes including cyanide, barium, manganese, and phenolic hydrocarbons. In California, C-SAW's John Stonich is investigating a State Water Resources Board policy that automatically provides a tenfold dilution allowance to any discharger who releases pollutants into "deep water" - any waterbody with sufficient volume to provide a tenfold dilution at the point of discharge. Numerous "deep water" mixing zones are authorized in relatively shallow waterbodies, such as San Francisco Bay.

C-SAW and the Earthjustice Legal Defense Fund are also leading a broader attack on state and federal mixing zone regulations, arguing that mixing zones are squarely at odds with the intent of the Clean Water Act (CWA). Congress realized when it passed the CWA in 1972 that the goal of zero discharge would not be reached overnight. The EPA was therefore required to adopt a federal Antidegradation Policy (ADP) that permitted pollution discharges that posed no threat to "existing uses" such as drinking water, fish propagation, and recreation in public waterways. The EPA justifies removing "existing uses" protections from waters inside mixing zones based on the notion that Congress did not intend the CWA to protect the whole waterbody, but rather the waterbody as a whole. This is a strange interpretation of a law that once set, as a national goal, the total elimination of "the discharge of pollutants into the navigable waters." The Clean Water Act required all states to incorporate ADPs that met or exceeded the Federal ADP into their water quality regulations. The EPA, however, permits every state to circumvent the ADP by exempting all waters within mixing zones.

Most states simply ignore the intent of the ADP. Alaska, in a demonstration of true frontier chutzpah, has adopted an ADP that explicitly excludes all waters in mixing zones. C-SAW has asked the EPA to reject the entire Alaska standards package under review.

Montana similarly circumvened federal ADPs in mixing zones. Steve Mashuda of Earthjustice explains: "The CWA's antidegradation rules require States to conduct a public and scientific review of all polluting activities to guarantee that already polluted waters do not get any worse, that cleaner waters are degraded only where absolutely necessary, and that pristine waters remain pristine. Montana's mixing zone regulations turn these requirements on their head by suspending the application of antidegradation rules within mixing-zones." The Earthjustice Montana office has filed suit in the federal court.

Mixing zones exist to save polluters money - money that should be spent on cleaning polluted effluent. If you know, or suspect, that a mixing zone has been granted in a local waterbody, contact C-SAW at Box 956, Haines, AK 99827, or phone (907) 321-4121.

Gershon Cohen (gershon@seaknet.alaska. edu) is the Project Director of C-SAW.