MARSSIM Overview

SADA version 4 includes a Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM) module. MARSSIM implements a nonparametric statistical methodology for the design and analysis of final status decommissioning surveys for the Nuclear Regulatory Commission. Nonparametric statistical methods for testing compliance with decommissioning criteria are provided for the case where radionuclides of concern are in background and also for when they are not in background. The tests implemented are the Sign Test and the Wilcoxon Rank Sum Test. The tests are performed in conjunction with an Elevated Measurement Comparison to provide confidence that the radiological criteria specified for license termination are met. Principles and methods from the Data Quality Objectives process are used for the planning of final site surveys. Methods for determining the number of samples for obtaining statistically valid comparisons with the cleanup criteria and the methods for conducting the statistical tests with the collected data are included.

A fairly focused approach is used in SADA for MARSSIM. This module was created under the close guidance of the NRC. The steps for performing MARSSIM analysis are as follows.

1. Create an empty SADA file.

2. Establish site boundaries and survey units.

3. Parameterize and create one or more MARSSIM sample designs.

4. Name/lock the created designs.

5. Import data into the empty SADA file

6. Associate newly imported contaminants with named designs.

7. Perform MARSSIM analysis.