By VICKI SMITHMORGANTOWN, W.Va. (AP) â¿¿ West Virginia regulators have made many changes to ensure massive coal slurry ponds don't fail from the bottom and flood underground mines, but federal officials said Thursday they must do more to document and reduce risks from nearby mining activity. Mining has the potential to destabilize loose or liquefied contents, and it's not good enough to rely on mine maps that may be outdated and inaccurate, the Office of Surface Mining and Reclamation Enforcement said in its third report on West Virginia's 132 slurry impoundments. Field director Roger Calhoun said OSM issued a variety of recommendations that the state Department of Environmental Protection is voluntarily embracing, but "not because we found any dire conditions." "We don't have any imminent threats to be taken care of," he said. West Virginia has already taken action where it knew mining was occurring, Calhoun said. "What we've said is, look again at minable seams" and rely on drilling, remote sensing technologies and other tools to ensure that mine activity is not happening. "If there's not mining," he said in a conference call with reporters, "there's no risk." The reviews began after the massive failure of a former Massey Energy impoundment in Martin County, Ky., in 2000. Slurry burst through the bottom of a 68-acre holding pond, sending black goo through an underground mine and into 100 miles of waterways. The spill polluted the water supply of more than a dozen communities and killed aquatic life before reaching the Ohio River. OSM says there have been three smaller failures, all in Virginia, since 1996. West Virginia has more slurry impoundments than any other state, but it hasn't had a major failure since 1972, when the earthen dam at Buffalo Creek collapsed after heavy rain. The ensuing flood killed 125 people, injured 1,100 others and left some 4,000 homeless.