WILLMAR - Coal is no longer king with Willmar Municipal Utilities.

The decision has been made to instead use primarily natural gas to power the plant.

For the past several weeks, the utilities staff and the Municipal Utilities Commission have been negotiating a long-term, uninterruptible natural gas supply contract to provide fuel to the plant until at least July 1, 2020. At that time, the utilities' district heating program will be discontinued. Whether the power plant will remain in operation after district heat is shut down is still being discussed.

Jon Folkedahl, director of electricity production with Willmar Utilities, said staff have been doing calculations regarding coal versus natural gas and found that natural gas prices have recently been cheaper than coal. Switching to natural gas will also make it easier to run the power plant with fewer people - it's expected that some employees may decide to leave before the July 2020 end of the district heating program.

Boiler 3, which can run on both natural gas and coal, will now be run only during the winter months.

"We've decided to, in a cost saving measure, to run number 3 as little as possible," Folkedahl. During the rest of the year, boiler 4 will run on natural gas.

The coal currently piled behind the power plant should be the last delivered. Folkedahl said the owner of the Montana mine where the coal is purchased has been told Willmar will no longer be purchasing the fuel and does not need any more rail deliveries.

"This is our emergency, emergency backup," Folkedahl said of the coal pile.

Natural gas is a cleaner burning fuel than coal. It also will help improve the utilities' stormwater runoff, since less coal will be stored outside.

"We want to be as environmentally friendly as possible," Folkedahl said.

The power plant has a stormwater management plan in place, which the Minnesota Pollution Control Agency oversees. As part of the plan, stormwater runoff from the power plant is tested and if it exceeds water quality benchmarks, like total suspended solids, the utilities is required to try to resolve the issues.

"We are required to take steps to mitigate the issues," Folkedahl said.

Since 2011 the utilities has been working on a plan to improve the quality of the stormwater runoff.

"They did have coal finds in it, but also had issues with just dirt, sand, normal stuff," Folkedahl said.

The mitigation plan had included constructing a sand filter which the water would have run though. However, with the long-term, ongoing discussions about the future of the power plant, the major work on the mitigation plan continued to be delayed.

"It's been in the budget for quite a number of years now. We hesitated to go to a lot of expense and construction if we didn't know if it was going to be there," Folkedahl said.

Now the larger project has been tabled completely, and Folkedahl said the utilities will do a few smaller projects to help eliminate any runoff from the coal pile.

The MPCA is on board with Willmar's plans regarding the plant and the stormwater project.

"As you might expect, they were pleased to hear that we wouldn't be burning coal," Folkedahl said.

While the fuel switch at the plant will change some of the operations at the utilities, customers should not see a difference.

"We have triple redundancy in place to protect their interest," Folkedahl said.

Probably the biggest effect the switch to natural gas could have is how the customers feel about the plant itself.

"The majority of people will feel better that their power plant is running on gas versus coal," Folkedahl said.