State will check mercury output at power plants

Colorado will start monitoring mercury emissions from power plants, a step toward a state rule dramatically slashing mercury emissions over the next decade.

Colorado's Air Quality Control Commission approved the monitoring rule Thursday.

Colorado Springs Utilities' two coal-fired plants, Martin Drake and Ray Nixon power plants, don't release enough mercury into the air to require continuous monitoring, nor will they be required to meet mandatory reductions, said Michael Brady, Utilities' technical services supervisor.

Federal environmental authorities estimate Colorado emits some 1,400 pounds of mercury a year, but an exact measure won't be known until the power plants are monitored. Mercury pollution can cause birth defects and heart problems. It can damage lakes and rivers, harming fish and birds and prohibiting anglers from eating what they catch.

In February, a federal court struck down proposed U.S. Environmental Protection Agency limits on mercury emissions. Colorado officials, like those in a handful of other states, decided to write their own.

Brady said Utilities officials have expected the new rules, and both coal plants fall beneath a threshold of 29 pounds of airborne mercury emissions a year. The average annual mercury release is 20 pounds at Nixon and 12 pounds at Drake, he said.
"Because of that, we are not required to do monitoring on a continuous basis. We only have to do periodic monitoring," Brady said. "We also fall below the thresholds where reductions are required."

Under the periodic monitoring, Utilities officials will do stack tests at regular intervals and report the results to the state.
There are 11 plants in Colorado that will be monitored for mercury emissions.