Sherry Appleman awoke abruptly in the middle of the night less than 48 hours after a pipeline rupture last month sent thousands of barrels of heavy crude oil into the streets and swamps of Mayflower, Ark.

"I couldn't breathe. My throat and nose and eyes were burning really bad," recalled Appleman, who lives on Lake Conway, about a mile outside the 22-home evacuation zone -- but next to a slough now full of the thick, sticky diluted bitumen. "I could smell that horrible smell. I got really scared."

ExxonMobil, owner of the ruptured Pegasus pipeline, maintains that none of the leaked Wabasca heavy crude mined from Canada's tar sands region has migrated into Lake Conway. The company also said air quality has remained safe for residents outside the immediate cleanup areas.

Nevertheless, health concerns are increasing.

Arkansas Attorney General Dustin McDaniel has set a Wednesday deadline for Exxon Mobil to comply with a subpoena demanding a slew of crucial pieces of evidence.

"When I left the site of the spill last week, I said that I came away with more questions than answers," McDaniel said Tuesday.

McDaniel hopes documents will start to answer some of the questions that linger over the oil spill that's rocked the community of Mayflower.

"Things about this industry, things about this type of crude, things about the environmental damages that are caused,"  he said.

Two women who live near an ExxonMobil pipeline that ruptured last week and spilled thousands of barrels of oil in central Arkansas filed a federal lawsuit against the company on Friday.

The class-action complaint from Kimla Greene and Kathryn Jane Roachell Chunn comes a week after ExxonMobil Pipeline Co.'s Pegasus pipeline ruptured in Mayflower, about 25 miles northwest of Little Rock. Crews are still working to clean up oil that spewed onto lawns and roadways and almost fouled nearby Lake Conway.

The women are seeking money to make up for "a permanent diminishment in property value," according to the complaint. Their complaint says the women are bringing their lawsuit on their own behalf and for other people who live near the pipeline in Arkansas.

Glacial ice in the Peruvian Andes that took at least 1,600 years to form has melted in just 25 years, scientists reported Thursday, the latest indication that the recent spike in global temperatures has thrown the natural world out of balance.

The evidence comes from a remarkable find at the margins of the Quelccaya ice cap in Peru, the world’s largest tropical ice sheet. Rapid melting there in the modern era is uncovering plants that were locked in a deep freeze when the glacier advanced many thousands of years ago.

Dating of those plants, using a radioactive form of carbon in the plant tissues that decays at a known rate, has given scientists an unusually precise method of determining the history of the ice sheet’s margins.