OAKLAND (AP) — Conservation groups are suing California's oil and gas drilling regulators over hydraulic fracturing, charging officials with failing to properly study the practice's environmental impacts. The lawsuit filed Tuesday in Alameda County Superior Court charges the California Department of Conservation, Division of Oil, Gas and Geothermal Resources, also known as DOGGR, with failing to adequately monitor possible pollution caused by hydraulic fracturing, or "fracking." Fracking is the practice of shooting water and chemicals at high pressure into underground rock formations to release oil or gas to the surface.