SANTA FE, New Mexico (Reuters) - Following a massive wildfire, crews at the Los Alamos National Laboratory have begun removing contaminated soil from nearby canyons out of a concern that flash flooding could wash toxins into the Rio Grande, officials said on Monday.
The Rio Grande is a source of drinking water for many communities in New Mexico, including the capital Santa Fe.
The Las Conchas wildfire, which scorched land in the canyons near Los Alamos before it was turned away from the lab earlier the month, has added urgency to the soil removal efforts because flash floods could rush unimpeded through canyon floors stripped of vegetation, officials said.
That concern is heightened by the monsoons that have arrived on schedule in northern New Mexico. The National Weather Service on Monday put out a flash-flood watch for the fire area through at least Wednesday.
The soil in the canyons above Los Alamos National Laboratory, the linchpin of American's nuclear weapons industry, contains materials with trace amounts of radiation and hazardous chemicals such as polychlorinated biphenyls (PCBs) that were dumped there decades ago, said Fred deSousa, spokesman for the lab's environmental control division.
Over the weekend, about 1,200 cubic yards of contaminated soil was removed primarily from two canyons -- Los Alamos and Pajarito -- that run through lab property, deSousa said.
The erosion control effort, which included the installation of 600 feet of water diversion barriers, will continue this week, he said.
Meanwhile, National Weather Service forecasts for the region in the coming days call for showers and thunderstorms, with hail, lightning and winds up to 45 miles per hour.
The monsoons bring with them the promise of helping to contain the Las Conchas wildfire, which is 50 percent contained and has burned nearly 150,000 acres since it broke out on June 26, when winds knocked an aspen tree against power lines.
"It's such a Catch-22 with the rains," said Arlene Perea, a fire information officer. "The rains are welcome, but we know there are some problems with it."
Last week, Governor Susana Martinez issued an emergency declaration to free up about $700,000 in state funds for flood mitigation efforts across the state.
On Monday, forestry officials seemed as hopeful as they have been since the fire began.
"We got a big rain on the fire this morning, and things are really looking good, especially on the north end," Perea said.
That area includes the Santa Clara Indian reservation where firefighters have been battling to save sacred and cultural Pueblo sites, including Chicoma Mountain, regarded as "the center of all" by many tribes.
Containment lines were said to be holding on the three sides of the mountain that were burning.
Fire lines also were holding north of Los Alamos and the nearby Pajarito Mountain ski resort.
Editing by Alex Dobuzinskis