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.
The large white band across the center of the photo is the culm mound which was said in 1919 to be 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. Berry Mountain can be seen in the distance, and the borough of Lykens is seen between the mountain and the culm mound.
Another use that was found for the culm was the creation of coal briquettes and a plant was constructed for that purpose just to the west of the trestle. That plant was in operation from about 1919 into the 1950s. This briquette plant provided employment for some after the Short Mountain Colliery closed in the early 1930s, but certainly not as many as were employed when the mines were in full operation.
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