Monday, June 16, 2003 | 11:16 a.m.
After more than a year, the state still has not approved a consultant's ground water monitoring plan for old wastewater evaporation ponds in Henderson, so plans to build 7,000 homes overlooking the Las Vegas Wash are on hold.
However, state officials and industrial representatives may be close to finalizing a cleanup plan.
It is the biggest environmental cleanup project in the state's history.
"We are still doing a large-scale evaluation of that area," said Allen Biaggi, Nevada Division of Environmental Protection administrator. "It's potentially a win-win situation for everybody."
It will be at least a few more years before homes could be built on the site, Biaggi said.
In addition to analyzing the area for heavy metals and pesticides, the state and the Southern Nevada Water Authority are checking ground water sources for benzene, a volatile organic compound that is common at gas stations and diesel fueling stops around the state, Biaggi said. Exposure to high levels of benzene causes cancer in humans, according to the Department of Health and Human Services.
There is no indication benzene has threatened Southern Nevada's drinking supply in Lake Mead, Biaggi said.
The federal limit for benzene in drinking water is five parts per billion, equal to a pinch of salt dissolved in an Olympic-sized swimming pool.
"However, we do not want to ignore potential environmental problems," he said. As far as benzene is concerned, it breaks down on its own and can be treated with beneficial bacteria, he said.
But that's not to say the cleanup at the former industrial site is a simple task.
Another Nevada Division of Environmental Protection official said the ground water monitoring plan for the Henderson site is expected "in weeks."
Drilling new wells at the site could begin this summer.
Jennifer Carr, an environmental administrator for the state Bureau of Corrective Actions, said Basic Remediation Co., a sister company of developer LandWell Co., had made progress on the environmental cleanup plans.
The state added ground water testing to Basic Remediation's list in spring 2002. The company estimates it will cost from $20 million to $40 million to clean up the site, depending on what scientists find in expanded testing.
There will be no building of homes, however, until state environmental officials are assured the contaminated soils and ground water have been addressed, Carr said.
Contamination appears most concentrated on 400 acres within 2,400 acres of land planned for development north of Boulder Highway and Lake Mead Drive. It remains unclear how deep the contaminants have leached into the soil and whether ground water will have to be pumped and treated.
The ponds are downhill from Southern Nevada's major industrial complex, built during World War II. After the plants produced about 166 million tons of magnesium to build light, fast planes, titanium metal continued to be manufactured. Pesticides were made there, as well as ammonium perchlorate, a booster for rocket and space shuttle fuels.
While titanium is still manufactured, the company, the state and the developers are working to clean up the contamination that includes solvents, heavy metals and pesticides.
"They have to meet rigorous steps through us," Carr said. "Optimistically, we are hoping (the final cleanup plan) is months away."
The state and the company are reviewing how to contain and clean up contaminants that are a legacy of 62 years of chemical manufacturing that began in 1941 with the Federal Defense Corp.'s production of magnesium.
A succession of private manufacturers, including Basic Magnesium Inc., dumped pesticides, arsenic, lead and other hazardous chemical by-products until 1976 when Congress passed laws governing chemical waste disposal. Today, about 100 acres of evaporation ponds remain active, used by Titanium Metals Corp.
Scientists working for LandWell conducted the initial soil tests at the BMI complex in 1995. Since that time, scientists have done another 60,000 soil tests.
When researchers discovered asbestos in the dry soils surrounding the ponds, Basic Remediation stockpiled contaminated piles of soil and encapsulated it to keep asbestos fibers in place, Carr said.
The soils became contaminated when industries disposed of wastewater running into the ponds on the the surface.
A plan has been approved to construct a landfill on Warm Springs Road, not far from LandWell's office, for the cleanup, Carr said.
However, the state's Bureau of Waste Management has not granted a permit to build the landfill, she said. Last summer officials delayed plans to transport 2 million cubic tons of contaminated soil while BRC finalizes the design of the proposed landfill.
Meanwhile, efforts continue to remove the rocket fuel booster ammonium perchlorate from the Las Vegas Wash. Wash waters enter Lake Mead, the major water source for the Las Vegas Valley.
The Southern Nevada Water Authority reported nine parts per billion of perchlorate in the lake's water this spring.
Kerr McGee Corp. and American Pacific Co., both makers of the salt ammonium perchlorate that boosts shuttle and rocket engine performance but can slow down human thyroid activity, have been treating contaminated water before it enters the wash for more than two years.
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