MAROS: A Decision Support System for Optimizing Monitoring Plans

Abstract

The Monitoring and Remediation Optimization System (MAROS), a decision-support software, was developed to assist in formulating cost-effective ground water long-term monitoring plans. MAROS optimizes an existing ground water monitoring program using both temporal and spatial data analyses to determine the general monitoring system category and the locations and frequency of sampling for future compliance monitoring at the site. The objective of the MAROS optimization is to minimize monitoring locations in the sampling network and reduce sampling frequency without significant loss of information, ensuring adequate future characterization of the contaminant plume. The interpretive trend analysis approach recommends the general monitoring system category for a site based on plume stability and site-specific hydrogeologic information. Plume stability is characterized using primary lines of evidence (i.e., Mann-Kendall analysis and linear regression analysis) based on concentration trends, and secondary lines of evidence based on modeling results and empirical data. The sampling optimization approach, consisting of a two-dimensional spatial sampling reduction method (Delaunay method) and a temporal sampling analysis method (Modified CES method), provides detailed sampling location and frequency results. The Delaunay method is designed to identify and eliminate redundant sampling locations without causing significant information loss in characterizing the plume. The Modified CES method determines the optimal sampling frequency for a sampling location based on the direction, magnitude, and uncertainty in its concentration trend. MAROS addresses a variety of ground water contaminants (fuels, solvents, and metals), allows import of various data formats, and is designed for continual modification of long-term monitoring plans as the plume or site conditions change over time.

Reducing Spatial Sampling in Long-Term Groundwater Monitoring Networks Using Ant Colony Optimization

“…As in other LTM optimization works [2], this study assumes that the contaminant plume is stable because of previous contaminant transformation or remediation activities and that the groundwater monitoring data used for optimization has undergone review and standard quality assurance/quality control practices. Thus LTM optimization is considered during the later stages of remediation projects.…”

“…Reference [2] developed the monitoring and remediation optimization system (MAROS), which is a decision support system that uses a ranking rule-based approach combined with Delaunay triangulation to reduce sampling locations and statistical methods to reduce sampling frequency. Reference [5] developed the Geostatistical Temporal/Spatial (GTS) optimization algorithm, which is a site specific technique based on kriging and is applicable to sites with a large number of monitoring wells.…”

Assessment of the Groundwater Protection Program Y-12 National Security Complex, Oak Ridge, Tennessee

“…Results generated from the software tool can be used to develop lines of evidence, which, in combination with expert opinion, can be used to inform regulatory decisions for safe and economical long-term monitoring of groundwater plumes. For a detailed description of the structure of the software and further utilities, refer to the MAROS 2.1 Manual (AFCEE, 2003; http://www.gsinet.com/software/MAROS_V2_1Manual.pdf) and Aziz et al, 2003.…”

The Scenarios Approach to Attenuation-Based Remedies for Inorganic and Radionuclide Contaminants

“…For example, the MAROS program (Aziz et al 2000;Aziz et al 2003) is a public-domain freeware developed by the U.S. Air Force that can help identify trends in temporal groundwater datasets.…”