I would think that that has come from all the coal mining that has been done in the erea for years.The spring itself is running out of a reclaimed hillside that was mined more than 22yrs. ago. Thats how the pond got to be originaly constructed. It was built by the mining Co. to catch sediments & stop soil erosion. It has a very thick all clay lining but due to the age, 15ft depth & trees growing on the dam I do have seepage at the base of the dam. It does still fill much faster than it leaks out though.

Dan B