Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: WEDNESDAY, June 20, 1990 TAG: 9006200005
SECTION: NATIONAL/INTERNATIONAL PAGE: A-4 EDITION: STATE
SOURCE: Cox News Service
DATELINE: TEMPE, ARIZ. LENGTH: Medium
Testing the flow, the men hoist down a robot sampling unit and spray it with ultraviolet evidence powder before climbing back into the night to make their escape.
Sherlock Holmes would be proud.
Things are changing in the sewers. The waste-water workers in Tempe are not all blue-collar grunts with deadened nostrils and questionable grime beneath their fingernails - some of them are highly trained investigators on the trail of high-tech crime.
They call themselves sewer cops, and they prowl drains and culverts searching for the traces of hazardous wastes that unscrupulous businessmen dump into the system.
The industrial waste section of the Tempe's waste-water department was formed in 1983 in response to a growing number of high-tech industrial facilities and small shops that used hazardous chemicals. The chemicals are dangerous, some highly toxic. Industrial Waste Supervisor Alan Jensen estimates there are 25 to 30 businesses in Tempe that use cyanide.
"Once the hazardous material is released into the environment, you can't call it back," Jensen said.
The same chemicals that are hazardous to our health are hazardous to bacteria, too. That's a big part of the problem - sewage treatment plants run on bacteria.
Like a giant stomach, the bacteria in treatment plants digest the sewage, passing it as recycled water. But if the bacteria are killed off, by cyanide or any toxic waste, the system shuts down. In sewer talk, it's known as an "upset stomach."
"It's just like a person," Jensen said. "The tanks regurgitate, and away it goes."
That can be costly or even dangerous, so the inspectors are armed with numerous state and federal statutes that make flushing the chemicals illegal.
Disposal companies charge from $100 to $700 a barrel to take away these wastes. Hence, it's the smaller, growing companies that are often the worst offenders. They simply don't want to pay the extra costs.
Tracking the offender down is the hard part. Strange chemical odors are often a sign that a polluter is dumping again, and investigators also rely on tips. But routine checks on sewer drains throughout the city are often the first indicators of trouble.
Inspectors often plant robotic samplers in the sewer late at night and can program them to begin sampling days later - that way, plant operators can't readjust their dumping schedules to get around the sampler. Ultraviolet powder sprayed on the samplers lets inspectors know if the robotic snoops have been tampered with - a simple show of hands under ultraviolet light spotlights the guilty worker.
by CNB