. >> reporter: it was a sunday afternoon after church 13 years ago that beverly butler and her husband bob lit a fire she says moments later, their home exploded >> this ball of fire hit me in the face, and the next thing i knew, he hollered, we got to get out, the house is on fire. >> reporter: like the house that blew up over the weekend in plum, pennsylvania, the butlers' home three hours north in bradford is surrounded by old abandoned and unplugged oil and gas wells. the butlers' fire was so intense, investigators said they could provide no conclusive explanation for the gas explosion, and the cause of the explosion in plum is still under investigation, though pennsylvania officials told nbc news abandoned wells are being looked at as one possible cause the dangerous remnants of 100 years of searching for oil and gas, often dug by companies now long out of business, leaving open holes, which can cause toxins and dangerous greenhouse gases to leak into water supplies and, in some extreme cases, cause explosions nearly 5 million people across the country live within a half mile of o

but it's also something that can help us combat climate change. >> reporter: as for beverly butler, she wants answers. >> kids kept telling me, mom, there's something else he's got in store for you. something else you have to do. and i kind of figure maybe this is it, what he wants me to do. >> reporter: to see this through. >> to make sure that this does not happen to anybody else >> reporter: cynthia mcfadden, nbc news, bradford, pennsylvania. >>> the death toll in the dominican republic has risen to 27 after an explosion in a hardware store a 4 month old baby is among the victims. the country's emergency services says an additional 59 are injured. four buildings were destroyed. the president says the cause is under investigation. >>> amazon pharmacy is launching a new feature that will automatically apply coupons to reduce the price of insulin to as low as $35 a month. the discount will apply to more than 15 major brands, including eli lilly and sanofi this will help simplify the process of searching for coupons and help people save on life-saving medication that has been notoriously