LOS ALAMOS, N.M. (AP) - Crews at the Los Alamos National Laboratory have completed the first of a series of projects designed to prevent any trace of nuclear and other contamination from being washed downstream by flooding triggered by the huge Las Conchas fire.

Lab spokesman Fred deSousa says crews installed water diversion barriers and removed more than 1,200 cubic yards of sediment over the weekend. They also sealed wells and installed sampling stations that will test runoff.

The work is designed to help stabilize canyons and prevent runoff from stirring up trace amounts of Cold War-era contamination.

The fire burned only one acre of lab property but did burn off vegetation in two canyons upstream. Heavy runoff from monsoon storms is expected to cause flash-flooding over the summer.

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