• picture
  • picture
  • picture
  • picture
Public Radio's Environmental News Magazine (follow us on Google News)

Mixing Zones

Air Date: Week of

In a trial run for an expected nationwide ban, the EPA says no more “mixing zones” in the Great Lakes region for 22 highly toxic chemicals. Mixing zones are places in which it was thought water dilutes pollutants, but new research shows that’s not always the case. The Great Lakes Radio Consortium’s David Sommerstein reports.


CURWOOD: Envision the oil slick that trails an outboard motor. If you watch long enough, the oil seems to disappear into the surrounding water. What you're looking at is called a mixing zone. The Clean Water Act of the early 70s used mixing zones as a compromise between environmental and industrial concerns. The law allows factories to release some toxic chemicals directly into water at high concentrations. The idea was that the chemicals would be diluted in the mixing zone to lower levels downstream. But the U.S. Environmental Protection Agency recently announced a phase-out of mixing zones in the Great Lakes and the St. Lawrence River. The ban will serve as a test case for similar standards nationwide. The Great Lakes Radio Consortium's David Sommerstein tells us why.

(Water slapping)

SOMMERSTEIN: On a blustery day along the St. Lawrence River in northern New York, Ken Jock stands on Racquet Point. It's Mohawk tribal land. Jock directs the environment division of the St. Regis Mohawk tribe. He points out an abandoned shack and dock. He says the area used to be a popular fishing camp.

JOCK: We used to be a fishing and hunting, trapping community that was the traditional way of providing for your family.

SOMMERSTEIN: The St. Lawrence and its tributaries are central to Mohawk culture, spirituality, and the tribe's economy. But when toxic fish advisories began popping up, it was no longer possible to make a living fishing, so the camps closed. Jock looks upriver to the factories on both sides of the U.S.-Canadian border. He blames the discharge pipes of these plants for disrupting his people's lifestyle.

JOCK: The solution to controlling that pollution is not to dilute it within a mixing zone. You have to cut it off right at the source.

SOMMERSTEIN: The U.S. Environmental Protection Agency agrees with Ken Jock. It recently announced a ban on mixing zones in the Great Lakes watershed for twenty-two toxic chemicals. They're called bioaccumulative chemicals of concern, or BCCs. They include PCBs, dioxin, and mercury. The EPA singled out these pollutants because they don't dilute and disappear as once thought. Instead, research now shows they build up in fish and aquatic plants over time. Charles Fox is the assistant administrator for the EPA's Office of Water.

FOX: These are chemicals that might get into the Great Lakes through the air or through the water. They don't really flush out of the system, and they stay there and they can be accumulated into the food chain. So that ultimately, the fish that we eat on our kitchen table could be contaminated with toxic chemicals.

SOMMERSTEIN: The mixing zone ban has been in the works since 1995, when the bi-national Great Lakes Water Quality Agreement beefed up pollution guidelines in the region. Most Great Lakes states have already banned mixing zones for these chemicals in an effort to protect the cleaner upper lakes: Superior, Huron, and Michigan. Only New York, Ohio, and Pennsylvania still need to put the new regulations in place. The EPA says the ruling will reduce these toxic pollutants in the Great Lakes by 700,000 pounds in the coming years. But industry groups say the ban will have little practical effect because most BCCs were banned years ago in all eight Great Lakes states. The ban on mercury, however, is where industry will feel the pinch. Mercury is a contaminant in the production process. It's not a raw material. The EPA predicts a ninety percent reduction in mercury discharges from the ban. Joe Mayhew, spokesman for the American Chemistry Council, which represents manufacturers, agrees it's important to reduce mercury levels in the water. But, he says, the ban places an undue financial burden on industry.

MAYHEW: Mercury is just a trace contaminant in a lot of things. To comply with these rules, what you do is you treat your discharges down to essentially zero, and that is an extremely expensive proposition.

SOMMERSTEIN: The EPA estimates the ban will cost industry up to $35 million to implement. Mayhew puts that figure closer to a billion dollars. Mixing zones are still permitted in the U.S. and Canada for many other chemicals, and with tens of thousands of different chemicals being produced in both countries each year, it's tough to predict how much the ban of these twenty-two toxins will improve overall water quality in the Great Lakes. Meanwhile, the Great Lakes ban on mixing zones will serve as a test case for a national ban the EPA is expected to propose next year.

(Water splashing)

JOCK: It's just a beautiful area.

SOMMERSTEIN: Standing by the abandoned fishing camp on the St. Lawrence, Ken Jock says the St. Regis Mohawks see the river's health over a longer term than even the EPA's timeline.

JOCK: I think that the river can rebound. I think that it's all a matter of time; twenty-two chemicals right now is just a start.

SOMMERSTEIN: Jock says despite the polluted water, his people still derive their spirituality from the river as they have for generations. And he expects those beliefs to outlast the legacy mixing zones leave behind. For Living on Earth, I'm David Sommerstein.



Living on Earth wants to hear from you!

Living on Earth
62 Calef Highway, Suite 212
Lee, NH 03861
Telephone: 617-287-4121
E-mail: comments@loe.org

Newsletter [Click here]

Donate to Living on Earth!
Living on Earth is an independent media program and relies entirely on contributions from listeners and institutions supporting public service. Please donate now to preserve an independent environmental voice.

Living on Earth offers a weekly delivery of the show's rundown to your mailbox. Sign up for our newsletter today!

Sailors For The Sea: Be the change you want to sea.

Creating positive outcomes for future generations.

Innovating to make the world a better, more sustainable place to live. Listen to the race to 9 billion

The Grantham Foundation for the Protection of the Environment: Committed to protecting and improving the health of the global environment.

Contribute to Living on Earth and receive, as our gift to you, an archival print of one of Mark Seth Lender's extraordinary wildlife photographs. Follow the link to see Mark's current collection of photographs.

Buy a signed copy of Mark Seth Lender's book Smeagull the Seagull & support Living on Earth