By JONATHAN MATTISECHARLESTON, W.Va. (AP) a¿¿ West Virginia Gov. Earl Ray Tomblin and U.S. Sen. Joe Manchin on Monday proposed tighter regulations for chemical storage facilities after a spill contaminated the water supply for 300,000 people. Tomblin, the Democratic governor, urged passage of a chemical storage regulatory program. The bill aims to address shortcomings that allowed 7,500 gallons of coal-cleaning chemicals to seep into the Elk River on Jan. 9. Freedom Industries, which owned the plant that leaked the chemicals, filed for Chapter 11 bankruptcy Friday. Freedom Industries' safety flaws, including a last-resort containment wall filled with cracks, went largely undetected, because as a facility that neither manufactured chemicals, produced emissions, or stored chemicals underground, it was not subject to environmental regulations, state Department of Environmental Protection officials have said. The chemical that spilled also wasn't deemed hazardous enough for additional regulation. The material flowed 1.5 miles downstream and made it into West Virginia American Water Company's water supply. Below-ground tanks storing chemicals face environmental regulations, but ones above the surface fall into a regulatory loophole, officials have said. The department made several routine visits to the Charleston site between 2002 and 2012, but found no violations. The governor's bill, which hasn't been filed yet, would mandate annual inspections of above-ground chemical tanks, and would require water systems serving the public to draft emergency plans in case of spills. Storage facilities would self-report locations, construction and maintenance of tanks, and file annual reports. They would need to detail their spill-prevention mechanisms, and would be subject to penalties from the Department of Environmental Protection if they don't comply. "This proposed legislation will ensure that all above-ground storage facilities are built and maintained consistent with required safety standards," Tomblin said. Manchin, D-W.Va., wants the federal government to set standards for state-run regulatory efforts. His proposal would require states to inspect chemical facilities that could threaten a public water system every three years. Others would be inspected every five years. States could recoup costs from responding to emergencies. The bill is also supported by U.S. Sens. Jay Rockefeller, D-W.Va., and Barbara Boxer, D-Calif.