1906 - 1920: Union Pacific Coal Company's No. 3 Mine in Hanna
The Union Pacific Coal Company's No. 3 mine in Hanna was closed in 1920 because the mine was worked out. The No. 3 mine opened coal production in 1906. The mine was open for 15 years and produced a total of 2,130,342 tons of coal over that time. The mine’s peak production was 326,751 tons of coal produced with 170 workers in 1910. Over time the Hanna Basin mines (Hanna, Elmo, Sampo, Carbon, Dana, and Wagon mines) experienced a total of 372 miner deaths. The No. 3 mine in Hanna was responsible for 6 of the 372 deaths.