ML12334A779

Official Exhibit - NYS000261-00-BD01 - EPA Technical Brief, Evaluation of Five Technologies for the Mechanical Removal of Radiological Contamination from Concrete Surfaces (March 2011) (EPA Technical Brief)

ML12334A779
Person / Time
Site:	Indian Point
Issue date:	03/31/2011
From:	Environmental Protection Agency
To:	Atomic Safety and Licensing Board Panel
SECY RAS
References
RAS 21596, 50-247-LR, 50-286-LR, ASLBP 07-858-03-LR-BD01
Download: ML12334A779 (3)

Text

United States Nuclear Regulatory Commission Official Hearing Exhibit Entergy Nuclear Operations, Inc.

In the Matter of:

(Indian Point Nuclear Generating Units 2 and 3)

ASLBP #: 07-858-03-LR-BD01 Docket #: 05000247 l 05000286 Exhibit #: NYS000261-00-BD01 Identified: 10/15/2012 NYS000261 Admitted: 10/15/2012 Withdrawn: Submitted: December 21, 2011 Rejected: Stricken:

Other:

Evaluation of Five Technologies for the Mechanical Removal of Radiological Contamination from Concrete Surfaces

Background

Because of its potential for deployment as a terrorist weapon in an urban setting, the radiological dispersion devise (RDD), the dirty bomb, is a very real and significant danger. The National Response Framework, the federal document that details how the nation responds to such threats, identifies the U.S.

Environmental Protection Agency (EPA) as a lead federal agency for decontamination following a radiological incident. This response to a radiological incident could include decontamination of buildings, equipment, and outdoor areas.

Thus, to support its designated role, EPAs National Homeland Security Research Center evaluated the performance of five mechanical decontamination tools for their ability to remove the radioactive isotope Cs-137 (Cesium-137) from the surface of unpainted concrete. In addition, NHSRC evaluated these tools for various deployment-related characteristics.

The work, completed in 2010, is described in a series As part of U. S. EPAs Office of Research and of reports. These peer-reviewed reports provide Development, the National Homeland Security Research rigorous evaluations of the efficacy of five Center (NHSRC) provides products and expertise to commercially-available surface cleaning tools of the improve our nations ability to respond to environmental type that could be employed to decontaminate contamination caused by terrorist attacks on our nations concrete surfaces following an RDD incident water infrastructure, buildings and outdoor areas.

releasing Cs-137.These reports can be accessed via NHSRC conducts research related to:

the NHSRC website (www.epa.gov/nhsrc/). The reports provide information that emergency x Detecting and containing contamination from responders can use in recommending or selecting chemical, biological, and radiological agents appropriate technologies for use during cleanup x Assessing and mitigating exposure to operations. This information can also be used to contamination assist federal, state, and local emergency x Understanding the health effects of contamination management authorities and emergency response x Developing risk-based exposure advisories planners to prepare for radiological homeland security x Decontaminating and disposing of events. contaminated materials.

Results A summary of the decontamination efficacy results is presented in Table 1. Unpainted concrete coupons (standardized samples) were contaminated with Cs-137 and the amount of contamination (radiological activity) deposited on each coupon was measured.

Each coupon was then treated with the decontamination technology under investigation March 2011 This document does not constitute nor should be construed as an EPA endorsement of any particular product, service, or technology.

and the amount of contamination was re-measured. The efficacy of the decontamination technology is expressed as percent of contamination removed (%R) and decontamination factor (DF). These efficacy measures are determined based on the following relationships:

%R = (1-Af/Ao) x 100%

DF = Ao/Af

%R = percent of contamination removed DF = decontamination factor Ao = radiological activity from the surface of the coupon before decontamination Af = radiological activity from the surface of the coupon after decontamination For each technology, the product name in Table 1 is hyperlinked to the corresponding report in the EPAs Science Inventory database. Deployment-related characteristics are presented in Table 2 grouped by type of technology (grinding vs. ablative).

Table 1. Decontamination Efficacy Decontamination Efficacy Product Technology Type

%R DF Dust Director with Wire Brush Grinding 38 r 7 1.6 r 0.2 Dust Director with Diamond Flap Wheel Grinding 89 r 8 14 r 8.5 CS Unitec Sander Grinding 54 r 10 2.3 r 0.07 River Technologies Rotating Water Jet Ablative 36 r 4 1.6 r 0.09 Empire Abrasive Blast nVac Ablative 96 r 3 41 r 21

%R, percent of contamination removed; DF, decontamination factor Table 2. Deployment Characteristics Parameter Grinding Technologies Ablative Technologies Decontamination Rate Approximately 1-3 m2/hr Approximately 5 m2/hr Applicability to irregular surfaces Irregularities kept some grinding heads Very applicable as surface is receiving from making good contact with the a pressurized blast of abrasive or surface; the more aggressive the water; ablative technologies are not grinding head the greater the final dependent on the surface terrain contact area Skilled labor requirement Brief training session adequate Brief training session adequate Utilities required 110V for both grinder and vacuum High pressure air compressor, hot water pressure washer Extent of portability Very portable Equipment requirements more significant, but hoses would likely allow access to most locations Setup time 30 minutes 2 days to assemble equipment, but once together setup would be minimal March 2011 This document does not constitute nor should be construed as an EPA endorsement of any particular product, service, or technology.

Table 2. Deployment Characteristics (cont)

Parameter Grinding Technologies Ablative Technologies Secondary waste management Very little waste as vacuum very Water spray during water blasting was effective in dust collection difficult to contain and could cause contaminant re-aerosolization which would be a safety concern; grit blasting vacuum worked well Surface damage CSU Sander - minor visible surface RT Rotating Water Jet - no visible damage surface damage DD Wire Brush - minor visible surface EA Blast nVac 2 mm of coupon damage, discoloration of surface surface removed leaving exposed aggregate DD Diamond Flap Wheel - top 1-2 millimeters of coupon removed leaving exposed aggregate Technology Evaluation Reports Referenced Drake, J. 2011. CS Unitec ETR180 Circular Sander for Radiological Decontamination.

Technology Evaluation Report. Washington, D.C.: U.S. Environmental Protection Agency.

EPA/600/R-11/018.

Drake, J. 2011. Empire Abrasive Blast NVac for Radiological Decontamination. Technology Evaluation Report. Washington, D.C.: U.S. Environmental Protection Agency. EPA/600/R-11/014.

Drake, J. 2011. Industrial Contractors Supplies, Inc. Surface Dust Guard with Diamond Wheel for Radiological Decontamination. Technology Evaluation Report. Washington, D.C.: U.S.

Environmental Protection Agency. EPA/600/R-11/013.

Drake, J. 2011. Industrial Contractors Supplies, Inc. Surface Dust Guard with Wire Brush for Radiological Decontamination. Technology Evaluation Report. Washington, D.C.: U.S.

Environmental Protection Agency. EPA/600/R-11/016.

Drake, J. 2011. River Technologies LLC 3-Way Decontamination System for Radiological Decontamination. Technology Evaluation Report. Washington, D.C.: U.S. Environmental Protection Agency. EPA/600/R-11/015.

Contact Information For more information, visit the NHSRC Web site at www.epa.gov/nhsrc Technical

Contact:

John Drake (drake.john@epa.gov)

General Feedback/Questions: Kathy Nickel (nickel.kathy@epa.gov)

March 2011 This document does not constitute nor should be construed as an EPA endorsement of any particular product, service, or technology.