The Texas Commission on Environmental Quality has set the hearing for 7 p.m. at the boardroom of the city of San Antonio's Development and Business Services Center at 1901 S. Alamo St. A similar hearing was Tuesday in Austin. The commission is not proposing changes to the rules that put special conditions on construction over the environmentally sensitive Edwards Aquifer and the areas that drain into it. But the agency is required to hold annual hearings on the rules. The aquifer can be easily polluted because it's readily refilled by rainfall runoff and stream flows in a 5- to 40-mile-wide area of exposed limestone that's marked with caves and faults. Annalisa Peace, executive director of the Greater Edwards Aquifer Alliance, a coalition of 41 groups seeking to protect the aquifer and its related Hill Country ecosystems, said the alliance will again ask for tougher development rules. "We're disappointed that TCEQ has taken little action to strengthen the Edwards rules following our 2005 recommendations, which were signed on to by 35 large statewide groups," Peace said. "So we're reiterating our comments from 2005 and ask that TCEQ act now to incorporate these measures before further degradation of the Edwards Aquifer and its ecosystem occurs." The San Antonio Water System will be asking the state agency to beef up its staffing and to spend more time inspecting structures designed to filter pollutants from stormwater flows, said SAWS spokeswoman Anne Hayden. The Edwards Aquifer Authority is in the midst of proposing rules on hazardous materials storage that would require many businesses to upgrade storage tanks and other containment measures. It won't be suggesting changes to the state rules, an authority spokesman said. Next month, the staff of the state agency is scheduled to propose increases in fees for reviewing all plans required for building over the aquifer's recharge and contributing zones. Separate public hearings will be held on the increases, which were authorized in a bill the Legislature approved this year. jneedham@express-news.net