Hanford’s Work With Robotic Arm Slow And Halting At Tank Farms

Mar 21, 2012

RICHLAND, Wash. – At the Hanford Nuclear Reservation in southeast Washington, the race is on to clean up radioactive sludge buried in aging underground tanks. Some of that waste has already leaked into the soil not far from the Columbia River. But attempts to use high-tech robotics to hose out waste tanks haven't gone as planned. And an important federal cleanup deadline is fast approaching. Correspondent Anna King visited one Hanford tank farm to see what’s causing the delays.

More than a year ago, I went to see the Mobile Arm Retrieval System, or MARS, being installed at Hanford’s so called C Farm. MARS is a massive, highly sophisticated, swivel-y robotic arm. It’s designed to clean radioactive sludge out of house-sized underground tanks. Back then, Scott Sax was a manager for the government contractor Washington River Protection Solutions.

Sax: “If the mobile arm retrieval system works like it’s designed, works like we think it will, it will help us pick up the pace dramatically …”

This promotional video shows the robotic arm blasting a dark witch’s brew of chemicals and radioactive isotopes. It’s an incredible technical challenge to clean up the leftovers from World War II and the Cold War.

MARS was supposed to be a game changer. But it has fallen far short of picking up the pace. Since 2010, the mobile arm system has only worked in an actual tank for four weeks. So what went wrong? An important pump, that’s part of the waste cleanup system and was supposed to last 5 to 10 years, broke down in December. And that pump had to be removed.

Recently I trekked back out to central Hanford to see that delicate operation. The guy in charge here is Kent Smith. He’s a serious, ex-Navy engineer with a focused gaze. He manages tank farm cleanup for Washington River Protection Solutions.

King: “So what’s happening Kent?”

Smith: “OK, so the crane is beginning to pull the pump out of the tank …”

Dozens look on as a handful of workers on scaffolding cover the pump in heavy-duty yellow plastic. It’s the size of a semi-truck trailer and emerges from the underground tank bit by bit. Imagine a giant banana coming out of a circus tent. After hours of work, the pump is safely deposited on the ground and the people in white suits high five.

This expensive machine is now rendered radioactive garbage. In fact it’s so radioactive, experts can’t tear it apart to see exactly what went wrong. Smith says it’s disappointing the pump had such a short life -- after it took nearly a year to just install and get working.

Smith: “But again these are very harsh environments for these pumps to be operating in. As a result you end up with failures.”

A federal judge has ordered the entire C Farm to be cleaned up by 20-14. Smith says his company is doing its best to work fast, but not at the expense of safety.

Smith: “Part of my job is to make sure that the people that do the work are buffered against that kind of schedule pressure. Because nothing would prevent us from meeting this milestone worse than having some kind of event.”

In the last 14 years federal contractors have cleaned out seven tanks. Six of those are in C Farm. There are 10 large ones left to go just in that farm alone. Deadline: 20-14. Smith’s company says it can make that goal. I asked Washington State Ecology’s tank farm manager Jeff Lyon whether that’s realistic.

Lyon: “We are all concerned about that deadline, and we are wondering how they’re going to make it. They have been slipping startup dates on all those other tanks ever since they started planning for it because of these difficulties.”

The MARS is scheduled to start work again by next month. Including C Farm, there are still a total of 170 more tanks to clean out here at Hanford.

Copyright 2012 Northwest Public Radio