'Gamma-Bob' hunts radioactive capsule

CREDIT: Tucker Wireline Services

The cylinder that has gone missing, pictured in inset above, is only about 19 millimetres long and 12 millimetres wide. It is part of a larger device, called a lithology density tool, which is used in petroleum exploration. The tool is about 75 centimetres in length.

EDMONTON -- An expert in radiation from Ottawa is on his way to Edmonton to help track down a tiny, but possibly dangerous, radioactive device that went missing on Tuesday.

Bob Grasty, who helped recover radioactive pieces from a Soviet satellite that crashed in Canada 1978, will join the search for the silver metallic cylinder, which is smaller than an AA battery and is part of a system used by oilfield companies in petroleum exploration and normally kept in a shielded container.

The cylinder contains radioactive material called cesium-137, used by the drilling industry to help characterize rock strata.

Workers at Tucker Wireline Services Canada said they last saw the device last Sunday, but found its container empty on Tuesday after the crew had travelled hundreds of kilometres through Saskatchewan and Alberta.

Mr. Grasty's expertise was requested Friday, and he was on a flight to Alberta yesterday. A radioactive guru, Mr. Grasty now runs his own business -- Gamma-Bob Inc. -- which has him working as a consultant with geophysicists and nuclear power plants, says his wife, Jenny. Mr. Grasty, 63, was the head of airborne geophysics during part of his 27 years at the Geological Survey of Canada.

An official with the Canadian Nuclear Safety Commission said the lost device is dangerous but only if it comes in close contact with people.

"This is a radioactive substance that emits gamma radiation, and it can cause radiation burns if it's close to the body for more than a few minutes," spokesman Michel Cléroux said.

The commission, which acts as Canada's nuclear energy and materials watchdog, has suspended Tucker Wireline's licence to use nuclear materials while the investigation continues.

Aside from radiation burns, exposure to cesium-137 may also increase the risk of cancer. This can happen even without touching the cylinder, said Carl Schumaker, a radiation safety expert at University of Alberta.

Within the cylinder are two curies -- units -- of cesium-137. Standing just a metre away from it for about 10 minutes would expose a person to more radiation than is deemed safe for an entire year, Schumaker says.

"It's not a small amount. It would certainly be a hazard to anybody that's within a reasonably close distance to the source."

According to a 1998 study by the International Atomic Energy Agency, "to the untrained eye, this unshielded source appears to present little hazard, and often persons have put the source in their pocket and taken it home, resulting in death or the amputation of limbs."

The small cylinder was last seen at an oil-drilling site 35 kilometres southwest of the village of Pierceland in northwestern Saskatchewan.

Since then, the Tucker Wireline truck carrying the cylinder has been to the company's branch in Leduc just south of Edmonton, and to another oil-drilling site in Wandering River, about 160 kilometres north Edmonton.

It was at Wandering River that workers discovered that the cylinder was missing.

"It's a major concern," said Jeff Levack, sales manager at the company's Canadian head office in Calgary. "The search is focusing along the highways, and in the bush where we were in Saskatchewan.

"Where we would really have a problem is if someone were to find the source, not know what it is, and pick it up and carry it around in their pocket."

As of last night, six hundred kilometres of roads in Alberta and Saskatchewan had been searched. Mr. Levack said workers are using gamma-radiation detectors mounted on trucks to search for the cylinder, and the company is considering using an aircraft.

Allan Seitz, a radiation safety expert and president of Alara Consultants Inc. in Edmonton, said while it's unlikely someone will be exposed to radiation from the cylinder, the potential exists.

Since 1996, there have been three incidents in which Alberta oilfield companies have lost their radioactive sources -- though they were all later found.

Some residents of Pierceland, a village of fewer than 500 people located northeast of Prince Albert near the Alberta boundary, were not impressed.

"It's strictly and totally negligent," said Jim Pettit from Shorty's Back coffee shop.

Pierceland Mayor Jim Krushelnitsky wasn't happy about the incident either.

"The people in town don't have a great worry but they want to see this thing found."