Special Robotic Tools Used in First-Ever Retrieval Of Cooling Coil Samples From SRS Waste Tanks

January 13, 2011

SRR guides demonstration of SCIX technology to remove radioactive constituents from liquid waste tanks.
Marshall Nielsen, senior project manager with Savannah River Remediation's F Tank Farm, points to coil cutter device used to cut pipes for accessing tank soil samples.

AIKEN, S.C. – According to a Savannah River Remediation (SRR) tank closure manager, one of three tools known as a Coil Cutting device will be used in a first-time-ever retrieval of cooling coil sections for sampling from a waste tank at the Department of Energy's Savannah River Site.

Two other tools will be used to sample residual waste material inside Tanks 5 and 6 as part of the process of operationally closing F Area tanks.

SRR officials say these sample tools will provide waste-related data from both tanks 5 and 6 that will assist in achieving operational closure.

Toby Hess, SRR Control Account Manager for Tanks 5 and 6 in the Waste Removal and Tank Closure Project, said the role of the closure sampling is directly correlated to SRR's mission to operationally close waste tanks.

"Tanks 5 and 6 are two tanks being prepared for closure and, once sampled, are ready for us to isolate and put grout inside them," Hess said.

He also notes that Tanks 18 and 19 are likewise being prepared for grouting after high-level, radioactive waste material has already been removed from the tanks.

The F-Area sampling process will deploy the three tools to retrieve waste samples from the waste tank interior.

The devices are implemented in the following manner:

  1. Crawler sampler: The robotic crawler, aka "G.I. Joe," crawls along the tank's ground-floor via two rubber track belts scraping sample material with a robotic arm lifting material into a basket for transport and examination.
  2. Core sampler: A straw-like device with a flexible bottom lip inserted into high level radioactive waste mounds inside tanks with objective of securing sample specimens and placing into a transport basket. Ultimately, samples will be taken to Savannah River National Laboratory (SRNL) for examination.
  3. Coil Cutter: A device used to help secure samples from waste tank cooling coils. In the accompanying photo, the (red) coil cutter works in conjunction with a grabber assembly. The coil cutter's hydraulic cylinder works to shear a candidate coil pipe section allowing the grabber to remove the sample section from the tank for examination.

Hess said sampling preparations started in September and would require about a month for each tank to be thoroughly sampled using the core, robotic crawler and the coil cutting device, the latter which he compares to a hydraulic plunger.

Both tanks should be completely sampled and prepared for isolation in the second quarter of 2011, he said. To date, at SRR, 15 waste tanks are in some phase of closure -- the most ever in the history of SRS.

A variety of SRR worker capabilities have been necessary to complete this project, said Hess. They include maintenance workers, radiological control, operations, work control and construction employees.

"Significantly enough, this will be the first time that we've ever retrieved a piece of cooling coil from a waste tank," Hess re-emphasized.

Savannah River Site is owned by U. S. Department of Energy. The SRS Liquid Waste contract is managed by SRR, a team of companies led by URS Corp. with partners Bechtel National, CH2M Hill and Babcock & Wilcox. Critical subcontractors for the contract are AREVA, Energy Solutions and URS Safety Management Solutions.

Point of Contact: Dean Campbell, Manager, Public Affairs dean.campbell@srs.gov