Date of Award

3-22-2018

Document Type

Thesis

Degree Name

Master of Science in Industrial Hygiene

Department

Department of Systems Engineering and Management

First Advisor

Jeremy Slagley, PhD.

Abstract

The radioactive fallout from the Fukushima Daiichi nuclear reactors accident and the ongoing threat of nuclear or radioactive terrorism have forced the need for urban radiological decontamination into the forefront. Many of the established decontamination techniques are not ideally suited for the urban milieu. One of the keys to maximize the effectiveness of long-term remediation and recovery in the urban environment is immediate mitigation within a few days of the incident and before a rain event. The Integrated Wash-Aid, Treatment, and Emergency Reuse System (IWATERS) provides a potentially safe and effective method for early responders and remediation teams to perform decontamination operations in urban areas. The system is set up with water barriers to catch wash water coming off of the building, pumps are then used to move the water through a series of absorbent beds, ion exchange filter, and finally into a holding bladder for eventual reuse. The goal of this research was to characterize: filter bed sizes for the decontamination of a modeled city block, exposure rates pre and post decontamination, and equivalent dose to early responders. The research found that the expected cesium activity from an entire city block can be contained safely in a filter bed of approximately one cubic meter. Shielding of the filter bed brings exposure rates down to a negligible level and enables the filter beds to be deployed in multiple configurations. The highest estimated exposure rate at the working locations of 0.66 milliroentgen per hour is kept below the Nuclear Regulatory Commission public exposure rate limit of 2 milliroentgen per hour. In addition, the worst-case expected equivalent dose of 46 millirem for a person who was exposed at the middle of the street for the entire decontamination process is below the 5,000 millirem guideline of the Environmental Protection Agency protective action guide for emergency responders and the 5,000 millirem per year limit for occupational radiation workers set by the Nuclear Regulatory Commission.

AFIT Designator

AFIT-ENV-MS-18-M-233

DTIC Accession Number

AD1056532

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