SOIL RADIONUCLIDE (-S) SEPARATION PILOT STUDY

ART Engineering, LLC

Hanford Project: Separation of Radionuclides Uranium, Thorium, Cesium  

This was the first pilot study for separation of radionuclides from impacted soils performed at the United States Department of Energy (DOE) Hanford, Washington site.  ART was responsible for all phases of the pilot study including:

Radionuclide Separation

Soil Feeding

Soil Separation - Plant Detail

 

The objective of this pilot study was to evaluate the capability and effectiveness of soil washing for removal of radionuclides from soils at the 300-FF-1 Operable Unit (OU).  Specifically, the pilot test was to determine the capability of soil washing to reduce the volume of contaminated material to <90% by weight, and to meet the specified treatment standards. The results of the soil washing operation were incorporated into the Phase III Feasibility Study in the context of evaluating soil washing for full-scale remediation at specified areas of the site.

 

The test was conducted on soils contaminated with low-level uranium, metals and organics.  Contamination originated from nuclear weapons production operations at the site from World War II until 1975.  Soils from two areas within the OU were processed (1) 300 tons of soil containing metals, organic materials and low-level uranium and, (2) 80 tons of soil containing elevated concentrations of copper and uranium.

 

The pilot plant utilized at this site had a throughput capacity of 10-15 tons per hour in a mobile, easily erectable configuration.  The plant consisted of a feed hopper, a double-deck wet screen, hydrocyclones, attrition scrubber, sand dewatering screen, sludge thickening and dewatering units, and the required supporting peripheral equipment.  The pilot study was successful in meeting the goal of >90% reduction by weight and was also successful in achieving the specified test performance standards.

 

Upon completion of the tests, ART submitted a written report to Westinghouse-Hanford Company for incorporation into the Feasibility Study. The following test results were attained:

 

 

Concentration

Contaminant

Test

Performance

Standard

Feed

Process

Oversize

(Clean)

Sand

(Clean)

Fines

(Residual)

 

Cu (ppm)

11,840

2,800

199

1,180

22,000

U-238 (pCi/g)

50

132

5.5

28.5

1,660

U-235 (pCi/g)

15

4.5

0.3

1.4

58

Cs-137 (pCi/g)

3.0

0.13

0.05

0.3

0.68

Co-60 (pCi/g)

1.0

0.08

<0.04

<0.06

0.93

  

RETURN to PROJECT EXPERIENCE

RETURN to HOME