When Great River Energy’s Coal Creek Station, the largest power plant in North Dakota, recently decided to upgrade its aged, mercury-containing switches in an effort to further its commitment to protect the environment and provide a safer workplace, the plant selected mercury-free Jerguson Tri-Magnet Level Switches from the Clark-Reliance^® Instruments and Controls Group. As the only ISO 14001-certified power plant in North Dakota, Coal Creek Station understands the importance of continuously evaluating and improving its environmental performance.

“The level switches we were using to monitor levels of our feed water heaters were older and contained mercury,” explains George Welder, E&I maintenance planner at Coal Creek. “The time was right to find a new, mercury-free solution.”

Welder first went to the OEM of the in-place switches to seek a mercury-free alternative. “They really didn’t have what I was looking for,” he recounted. “The alternatives they offered did not fully meet our needs, and installation of the new switches seemed as though it would be inconvenient and expensive.”

Finding the Solution

Then, while attending an energy conference, Welder found what he was looking for on display at the Clark-Reliance booth. After initial discussions with Clark-Reliance personnel, Welder was confident that the cost-effective, mercury-free Jerguson Tri-Magnet Level Switch would be an ideal replacement for his old feed water heater switches.

Welder trusted Clark-Reliance because of the company’s reputation, and the fact that other Clark-Reliance level equipment was in use and operating dependably in other parts of the Coal Creek Station plant.

“Some of the Clark-Reliance equipment here goes back a long time -- maybe close to 30 years,” he said.

The Jerguson Tri-Magnet Level Switches have been in operation at Coal Creek Station since May 2007.

“The new switches are very rugged and dependable, and most importantly, they are mercury-free and safe for the environment. Dealing with spilled mercury is an extremely difficult task, but it’s one we won’t have to worry about with these new switches,” said Welder.

Customers can also retrofit their current, contaminated level switches with Jerguson’s mercury-free, field upgradeable switch mechanism.