Coal oversupply concerns sink Walter Energy and Alpha Natural By: MarketMinute.com Stock News September 24, 2014 at 18:42 PM EDT Concerns about an oversupply of coal continued to weigh down shares of Walter Energy Inc. (NYSE: WLT) 57 cents to close at $2.24 and Alpha Natural Resources Inc. (NYSE: ANR) 33 cents to close at $2.55.