Employees of Environmental Assessment Services are living the good life this summer, getting paid to go fishing.

To make final plans for the environmental cleanup of the Hanford nuclear reservation, the Department of Energy and its regulators need to know more about the extent of contamination in the Columbia River.

That requires checking hundreds of fish, in part to assess their condition, but chiefly to test for any Hanford chemicals or radionuclides that could harm anyone eating those fish.

Someone has to catch the fish. And Environmental Assessment Services of Richland has been given that dirty job.

This past week, employees were fishing for sturgeon and walleye.

Boaters on the Columbia likely have seen their set lines, a commercial fishing technique the company is being allowed to use to catch 30 sturgeon for the study.

Two orange buoys that look like exercise balls bob in the water at each end of a set line. Underneath, eight hooks are baited with a seafood banquet -- squid, shad or commercially available trout -- and hung with 30-pound lead weights to keep them on the bottom of the river where the sturgeon feed.

On Tuesday morning Bruce Curet and Sam Gilbo of the company, accompanied by Tim Kiser of the U.S. Fish and Wildlife Service, were pulling in set lines just downriver from the White Bluffs.

First to break the surface of the water was an empty hook. Next, another empty hook. The third was empty too, but it had been pulled nearly straight, a sign that a sturgeon likely grabbed a snack and then pulled off.

Environmental Assessment Services keeps only those fish that are 43 to 54 inches long.

"Most of the oversize fish straighten out the hook, which is what we want," Curet said.

The next several hooks yielded only clumps of milfoil and some fleshy pink bait still on the line.

"Murphy's Law," Curet said. "There were four here yesterday."

But at another set of buoys the crew had better luck.

As they pulled the line up with a winch, the water surface was broken by the splash of a struggling fish before the sturgeon was quickly hooked onto a line alongside the boat while the other hooks were checked.

Sturgeon are ugly, believed to look much the same today as they did millions of years ago. They have no scales, but a row of boney plates called scutes runs the length of their bodies.

Their bellies are white, and this one's glowed in the morning sun as Kiser pulled it out of the water enough to run a scanner up and down its sides, checking for any microchip implanted in a previous study.

Once the crew flipped it onto its back in the boat, the fish went quiet. They measured it for the record, even though it obviously wasn't a keeper at just 32 inches long.

One of the men leaned over the boat and held it in the water for a few minutes to make sure it was oriented. He let it go and it disappeared.

The sturgeon have spawned and are slowly making their way downriver, said Brett Tiller, president of Environmental Assessment Services, which is doing the work as a subcontractor to Washington Closure Hanford. The trick is to find where they might be hanging out on a particular day.

When they find a good spot, the bite still drops off after a couple of days as the sturgeon get wise and the lines have to be moved to another area.

Since Environmental Assessment Services crews started fishing in July, they've caught 114 sturgeon but just 13 were the right size to keep. The youngest of them likely are about 15 years old. The largest sturgeon caught, which was returned to the river, measured 9 feet 8 inches.

But sturgeon aren't all the researchers are after. The crews started fishing in January, catching 100 whitefish. They've also caught 100 bass.

They're working on walleye now, which is a sweet job for the staff.

The whitefish, like 100 suckers and 100 carp to be caught later this summer, were collected through electrofishing. An electric current is run into the water from a boat near the shore to stun the fish. Then any fish of the right species are scooped up with nets.

But walleye must be caught with a fishing pole, just like the recreational anglers on the river use. Crews caught and kept their 27th walleye Tuesday morning and will keep spending their days on the river until they have 100 at least 18 inches long.

Testing will be done on a variety of organs and flesh from the 530 total fish in the study, with the smaller fish combined in groups of five for samples.

Labs under contract to Washington Closure Hanford will check for a wide variety of contaminants that might be linked to the past production of plutonium at Hanford for the nation's nuclear weapons program. Those include isotopes of plutonium and uranium, metals and PCBs.

The Washington State Department of Health has been hired to do quality assurance work for the study, and could choose to send some of the samples to be tested independently. Previous sampling has been done and has not led the Department of Health to issue any warnings specifically for fish caught near Hanford.

But this study, the most comprehensive conducted related to fish and Hanford, should provide more complete information. In addition to fish, assessment of the river also includes sampling of river water, soil on Hanford islands and sediment from the river.

Once all the data is collected and combined with extensive data collected in past decades, it will be used to assess the risk in different scenarios -- such as a Native American who eats fish every day from the Columbia River.

Then the Department of Energy, the state and the Environmental Protection Agency will decide if more investigation is needed or if enough is known to make final cleanup plans for Hanford land along the Columbia River, said Ella Feist, DOE manager of mission completion.

DOE is working to have most environmental cleanup along the river completed by 2015.

But more fish still are needed for the assessment.

Tuesday morning the Environmental Assessment Services crew fishing for sturgeon pulled in one keeper -- a 44-inch fish. They reset their lines and checked 80 hooks again 12 hours later.

In the meantime, they had some work to do -- figuring out where the sturgeon might be feeding. And for that they got out their fishing poles to spend a little time before they reset their buoys and lines.