Sunday, Oct. 12, 2008

Surprises found at old Hanford pistol range

By Annette Cary, Herald staff writer

Every Hanford cleanup project seems to have its surprises, and that's the case with even a seemingly straightforward project like cleaning up the old pistol range used by the Hanford Patrol.

Starting in the mid-'40s, the Hanford Patrol used firing ranges facing the north side of Gable Mountain for target practice in the center of the nuclear reservation. Pistols, rifles, machine guns and other small arms were fired toward the side of the mountain, along with grenades.

The cleanup of the firing ranges "is somewhat different because there is not radiation or something near reactors," said Cameron Hardy, Department of Energy spokesman at the site once used to make plutonium for the nation's nuclear weapons program. "But in cleaning up the site we have to think of a whole host of things, like relics from the '40s."

So far DOE contractor Washington Closure Hanford only has been assigned cleanup of the 7-acre pistol range. But the 55 acres used for target practice also included a rifle range, a machine gun range and a range for firing grenades from rifles.

The ranges are down a 1.5-mile dirt road that is seldom used, in part because Gable Mountain is considered a sacred Indian site and access to it by Hanford workers is restricted.

Washington Closure started preparing for the pistol range's cleanup two years ago by walking down the area, which has not been used for decades. They found plenty of bullets, along with a few live rounds.

But they also found two unexploded grenades lying in the dirt. They were about 8 inches long and shaped like a bomb with fins -- a type that was fired with a rifle.

"We realized we could not just got out and dig," said Rex Miller, field remediation operations manager for Washington Closure.

Signs were posted warning "Danger -- Keep out -- Possible unexploded ordnance."

This spring, an unexploded ordnance team was hired through subcontractor TerranearPMC to do a full walk-down of the pistol range and a nearby area that would be needed for waste containers.

First the site was cleared of visible metal debris, including a third unexploded grenade the team discovered.

Then seven unexploded ordnance technicians marked off grids and scanned them with sophisticated metal detectors. They created a map dotted with X's showing metal in the dirt, underneath pavement and in the hillside. They knew those could be wire, or grenades.

But before digging began Washington Closure, working with DOE and the Hanford Patrol, brought in an Army explosive ordnance disposal team from Yakima. They blew up the three grenades in June, concluding after the explosion that they were tear gas grenades.

Then a crew started digging up each suspicious area on the road into the firing range, in the embankment and under the asphalt. They found a lot of metallic rock and pieces of wire.

They also found another unexploded grenade in the bank of the hill and a fuse from a grenade. The grenade likely is filled with tear gas but that won't be confirmed until the Army comes back later this month to explode it, Miller said.

Subcontractor Federal Engineers & Constructors came in during September and made quick work of digging up the lead-contaminated soil. The dirt then was checked again by the unexploded ordnance team to make sure nothing of concern remained.

"We did a lot to ensure workers were protected," Miller said. "It should have been a slam dunk, but we took prudent measures to bring the right people in."