An undated view of the culm trestle at Short Mountain Colliery, Lykens Valley Coal Company, Bear Gap, Dauphin County, Pennsylvania. The culm, or combination of dirt, coal dust and rock as well as other unmarketable material, was taken as refuse from the breaker and spread on a large mound between the Wiconisco Creek, north of Lykens, and the operations of the colliery. When the colliery began to process the culm to create a fuel for the Lykens Power Plant at the site (after 1919), a washery was constructed which separated the dirt, rock and other unable material from the small particles of coal and coal dust that would be sent to the pulverizing mill to create the fuel to generate electrical power.
Across the top of the photo is the borough of Lykens. Just below, is the culm mound. In 1919, the mound was said to contain about two-and-a-half million tons of material which had been disposed of between the Wiconisco Creek, north of Lykens, and the colliery operations in Bear Gap. The mound was so high that residents of Lykens were unable to see the mountains to their north.
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