Concrete Grinder at the Hanford Site, Richland, Washington

Site Name:

Hanford Site


Richland, WA

Period of

November 1997


Field demonstration

Concrete Grinding
- Flex Model LD 1509 FR hand-held concrete grinder (6 lbs)
- 5-in diamond grinding wheel (10,000 rpm)
- 1.25-in. vacuum port for dust extraction
- Powered by 110 VAC, 11 amps

Cleanup Authority:
Not identified

Technical Contacts:
Stephen Pulsford, BHI, 509-373-1769
Greg Gervais, USACE, 206-764-6837
DOE Contacts:
John Duda, FETC

Jeff Bruggeman, DOE-RL

- Beta/gamma radiation

Waste Source:
Operation of a nuclear research reactor

Type/Quantity of Media Treated:
Debris (concrete) - 54ft2

Purpose/Significance of Application:
Demonstration of a light weight hand-held grinder to decontaminate radioactive concrete surfaces

Regulatory Requirements/Cleanup Goals:
The objectives of the demonstration were to evaluate the capability of a light weight, hand-held grinder in removing concrete

- Removed concrete from 54ft2 of walls and floors in the demonstration area to a depth of 1/16 in. at a rate of 48ft2/hr
- Contamination levels following demonstration were below free-release levels

Cost Factors:
- The costs for the Flex LD 1509 FR concrete grinder are - $649 equipment cost plus $205 for a replacement diamond grinding wheel; grinder can be rented for $25/day or $75/week
- The cost for the hand-held grinder were 40% less than the baseline technologies (scaller and scabbler)

The Flex concrete grinder is a lightweight, hand-held unit used to remove concrete and coatings from concrete surfaces. The electric powered grinder is equipped with a diamond grinding wheel and a vacuum port for dust extraction. The grinder was demonstrated on walls and flooring at the C reactor that were contaminated with beta/gamma radiation.

During the demonstration, the grinder removed concrete to a depth of 1/16 in from a total area of 54ft2. At the end of the demonstration, radioactivity levels were below free-release levels. The Flex grinder was compared to two baseline technologies - scabbler and scaler. The Flex grinder was found to be easier to use, more flexible, and more efficient that the baseline technologies, and overall to cost about 40% less. However, the life of the grinding wheel (manufacturer recommended change after 500ft2 at a depth of 1/16 in and the cost of a replacement wheel ($205) should be factored into the decision to use the technology. No specific changes or modifications to the grinder are needed for full-scale deployment.