popped nearly 7% in the previous session. Shares of the Tampa-based miner of coking coal (the kind used in steelmaking) were giving back 2% to $124.60. >>Basic Materials M&A: 4 Possible Deals Walter reported operating income of $144.7 million. On a per-share basis, the company said income from continuing operations came to $1.75 a share. That number includes more than $7 million in costs related to an acquisition and "long-term environmental monitoring," Walter said. Stripping out those costs, the company would have earned $1.85 a share. But that still came in below the consensus Wall Street forecast of $1.98 a share. Revenue, too, disappointed. Walter said its top line amounted to $400.8 million. Analysts were calling for revenue of about $440 million. In a note to clients Tuesday morning, analyst Mark Parr, of KeyBanc Capital Markets, blamed the shortfall on what Walter Energy called "difficult mining conditions" at its mines in Alabama. The problems led to lower-than-expected coal sales volumes during the quarter, Parr said. Walter said in its fourth-quarter report that those difficult conditions continued into January. Thus, Parr suggested in his note, first-quarter earnings estimates might need to come down. Walter gave a bit of guidance on this front, forecasting first-quarter sales volumes of metallurgical coal between 1.6 million and 1.8 million tons. By comparison, Parr had estimated 2 million tons. -- Written by Scott Eden in New York >To contact the writer of this article, click here: Scott Eden. >To follow the writer on Twitter, go to http://twitter.com/ScottEden. >To submit a news tip, send an email to: firstname.lastname@example.org.