The tiny town of Osage is situated in Northeastern Wyoming, about an hour and a half drive from Gillette by way of Moorcroft and Upton. It’s nestled in the bentonite foothills of the Black Hills and both Upton and Osage have nice stands of tall ponderosa pines. At one time, it was the sight of a coal-fired power plant owned by Black Hills Power that they began building in January of 1947 and the plant’s open house was held on May 12th, 1950. It was built to meet the increased demand for power post-World War II and at the time, was the biggest project Black Hills Power had undertaken.

At one point in the winter of 2002/2003, Gary’s Welding Inc. was commissioned to replace a portion of a stack at the power plant.
The bottom part of the stack was in good condition, but the top part had some corrosion and needed to be replaced. We had Empire Steel in Billings, Montana build the new section for us according to our specifications.
The new part of the stack was an ¼ inch thick, 8 ft. in diameter, 30 ft. long section of COR-TEN steel. It came with a nice, new work platform as well.
COR-TEN is specifically made for outdoor applications because it is corrosion-resistant and has great tensile strength. (For the nerds, read more here: https://www.azom.com/article.aspx?ArticleID=12974). COR-TEN is also made to not need paint – it’s great for artsy buildings or sculptures where a rusted, aged look is wanted. We chose to have the new part of the stack painted though, ’cause who wants see a rusty stack on the horizon, right? And it needed to fit in with the rest of the plant.
Because it was wintertime in Wyoming, this project posed another challenge. But we were excited for the opportunity to problem solve and come up with a way to get the

stack looking and operating like brand new in a short amount of time. The day that we actually replaced the stack turned out nice and sunny, which was a huge plus! The new portion was delivered to the plant and Gary and his team spent two days preparing everything on the ground and on the stack for the replacement.
A crane was brought in for the day of the replacement – and from the time the crane showed up to finish – the whole replacement process took between 8 and 10 hours. That included all the cutting, removing, replacing, welding and finishing the ladder!
Here are some pictures of that day:
Old portion of the stack being cut and lifted off.
Old portion gone and awaiting the new part (above).
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New section being placed (above) and finishing things up on the ladder and
ladder cage (below).
About a month after the replacement was complete, we contracted Sphere out of Gillette to come and sandblast and paint the old section of the stack so it would look more uniform.

Sadly, the plant was decommissioned in 2013 along with the Neil Simpson 1 plant in Gillette and the Ben French plant in South Dakota. The updates needed to comply with Federal regulations at that point were too costly, and Black Hills Power had them closed down.

We were sad to see her go, but are proud to have been a small part at the Osage plant. Aside from this project, we spent many years doing tube replacements and other boiler work at the plant. Good memories!
GWInc.