Three House Democrats have accused Halliburton and 11 other energy companies with pumping more than 32 million gallons of diesel fuel into the ground in 19 states in violation of the Safe Water Drinking Act. In a letter to the U.S. Environmental Protection Agency, California’s Henry Waxman, Massachusetts’s Edward Markey and Colorado’s Diana DeGette contend Halliburton and others dumped the fluid during a phase of natural gas extraction known as “hydrofracking.”