Peabody’s shares sunk by 13.5% while those of Cloud Peak Energy sunk by 11.3% in a day of volatile trade and amid gloom on coal mining and resources stocks.

Regulatory forces in the US and the declining market last month prompted broking house UBS to put a “sell” recommendation on Peabody Energy as well as on Powder River Basin powerhouse Cloud Peak Energy.

A report by industry analysts Wood Mackenzie last week suggested two-thirds of coal mines are losing money at current coal prices.

Peabody Energy may have to restructure with growing pressure on its balance sheet and the ongoing malaise in the US coal mining industry, a report by broking house JP Morgan states.

Several US coal mining companies are now facing the prospect of bankruptcy, with Arch Coal facing Chapter 11 risks, it states.

“Peabody bought itself time with its recent asset sale of three western bituminous mines for $US358 million in cash but we continue to feel that with the outlook for both coal and gas uninspiring for next year, we feel, Peabody may still have to restructure,” the JP Morgan report states.

“The two upcoming triggers are the large $70 million coupon payment due in March and a state review of its qualifications to self-bond its Wyoming AROs in Q2 2016.”

After a failed debt exchange, Arch is in talks with creditors for a possible restructuring as it highlighted in its Q3 earnings release. It has $90 million in coupon payments due on December 15 which could trigger a chapter 11 filing, according to JP Morgan.

Last month Cloud Peak Energy’s subsidiary Cloud Peak Energy Logistics LLC entered into an amended throughput agreement with Westshore Terminals to eliminate both parties’ volume obligations for the period 2016 through 2018 in exchange for a series of payments.

Under the amended agreement, Cloud Peak Energy made an upfront payment to Westshore and will make quarterly payments from 2016 through 2018 in lieu of the previous take-or-pay commitments during this three-year period.