EPA surveying damage storm did to landfill

The U.S. Environmental Protection Agency has investigated the storm-damaged breach in the old Sunrise landfill that allowed a flood of wastes to flow into a trench four miles from the source of the valley's drinking water.

Scientists from the EPA's Washington, D.C., headquarters last week surveyed the 35-foot by 70-foot hole torn into the dumpsite's cap during the Sept. 11 storm, said Lois Grunwald, who is in charge of landfills at the federal agency's San Francisco office.

The wastes ripped through a channel built to drain floodwaters from the east side of the site. The channel flows ran into the Las Vegas Wash, which drains the surface, ground and treated sewage waters from the valley. Six miles downstream Southern Nevada receives its drinking water.

"The EPA has been monitoring efforts to properly close the site since February," Grunwald said Thursday. "The EPA is aware of the severe storm and the damage it caused, including erosion and breach of the cap."

Grunwald said the Nevada Environmental Protection Division and the Clark County Health District are in charge of ensuring the landfill is secured.

Silver State Disposal Service Inc., operated the site until 1993. Silver State attorney Robert Groesbeck said up to 2.6 inches of rain fell at the landfill, making the Sept. 11 storm a 100-year event. But the National Weather Service said while the storm was severe, 1.5 inches of rain fell, making it a 25- to 50-year storm.

Silver State has been working to clear debris left from the flood, Groesbeck said.

The EPA has offered the Nevada Division of Environmental Protection and the Bureau of Land Management any technical assistance to ensure public and environmental protection, Grunwald said.

The NDEP is overseeing air pollution control, water monitoring and the cap replacement. The BLM raised the issue of a faulty cap in 1996 after its consultants discovered high levels of methane gas escaping from cracks in the landfill. One crack was 100 feet long.

The 760-acre site is leased by Clark County from the BLM. In turn, the county leased the site to Silver State in 1962 for a municipal dumpsite. Under a closure agreement, Silver State is responsible for maintaining the landfill and its cover.

The landfill must be maintained for 30 years under federal environmental regulations.

The EPA expressed its concerns about the landfill cover in a letter sent to county Public Works Director Marty Manning in March. Not only must the cap remain intact, the EPA said, but air pollution from methane gas and ground water monitoring are also required.

The EPA told Manning "immediate action" was necessary to properly close the landfill.

The county health district's Air Pollution Control Division has been monitoring gases from the landfill since spring. In addition to the landfill, sewage treatment plants in the area also produce odors.

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