Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of Walter Energy (WLTGQ), a producer and exporter of metallurgical coal used in steelmaking, tumbled as much as 11% after a regulatory filing today showed the company is attempting to refinance some of its outstanding debt.

So what: Walter Energy is seeking permission from its lender to repay a $407 million loan, and to refinance that loan with looser restrictions. Bloomberg reported that Walter Energy needs this concession since, under the current terms with its lender, it must also make repayments on a $978 million term loan B. If Walter Energy's lender complies with its requests, it would ease some of the coal company's' near-term obligations and give it more time to cut costs and wait for coal prices to stabilize and demand to improve.

Now what: Between rapid industrialization in China and India and a stabilizing U.S. economy, met coal should be nearing its trough. While a much smaller part of Walter Energy's business, I'm part of the dissenting group that believes thermal coal could still be a viable investment. On both counts, Walter Energy could be approaching its bottom. However, to survive and thrive once things turn around in the steep sector-wide downturn, Walter Energy needs to dig deep to reduce costs.