Approximate Cost: Free

Source:  GSI website (http://www.gsi-net.com/en/software/free-software/maros-30.html)

Current Version: version 3.0

Operating System Needs: Microsoft Office Access 2007 or 2010; Windows 7 (older versions of software are available compatible with Windows XP and earlier versions of MS Office)

Input Structure: Microsoft Excel spreadsheet or Access database


The Monitoring and Remediation Optimization System (MAROS) software was developed by GSI Environmental Inc. (GSI) on behalf of Air Force Civil Engineer Center (AFCEC), known previously as Air Force Center for Engineering and the Environment (AFCEE), in 1998. It is a public-domain, data management and evaluation tool specifically designed to improve long-term groundwater monitoring (LTM) programs using both qualitative and quantitative methods. MAROS provides both:

  1. Optimization routines, to help determine the appropriate number of sample locations, sampling frequency, and laboratory analytes for the specified monitoring objective
  2. Statistical analysis tools to evaluate the plume stability condition and the effectiveness of natural attenuation and active remediation efforts

Add-Ins Available


Ease of Use and Data Import

The MAROSMonitoring and Remediation Optimization Software tool analyzes groundwater data collected from a network of permanent or semi-permanent groundwater monitoring locations. Modules within the MAROS tool evaluate affected groundwater sites where substantial site characterization has already occurred. MAROS is not specifically designed for detection monitoring programs. The intended use of this software is to review data and evaluate the efficacy of the network to address site monitoring and remediation objectives.

The MAROSMonitoring and Remediation Optimization Software software uses site-specific data from the full historical record for statistical analysis and review. Groundwater analytical data can be imported into the software from AFCEC'sAir Force Civil Engineer Center's Environmental Resource Program Information Management System (ERPIMS) database or Microsoft Excel or Access files. Minimum data requirements for the MAROS tool include data from at least six monitoring locations with detected concentrations of contaminants and at least four sampling events. The software can evaluate data from as many as 200 wells (speed of calculations may be slow with more than 200 wells). Input files include data such as well name, X, Y coordinates, sample date, contaminant name, analytical result, detection limit, and data flags. 

The software can currently import data for over 2,000 different chemicals that may be dissolved in groundwater. Internal MAROSMonitoring and Remediation Optimization Software databases contain regulatory screening levels from various programs and physical parameters for these chemicals. Data from these databases are used to prioritize contaminants for long term monitoring optimization (LTMO) analyses.

Types of Distributions

The software contains modules that prioritize contaminants, calculate summary statistics, find outliers, identify data distributions, determine temporal trends at individual wells (using both Mann-Kendall and linear regression techniques), and calculate plume stability metrics and their trends over time (such as total dissolved mass, center of mass, and spread of mass).


MAROSMonitoring and Remediation Optimization Software has several data visualization options that allow you to review concentration versus time graphs and tables prior to more in-depth analyses. You can export results of analyses either as formatted reports, spreadsheet output, or database output at various locations in the software.

Primary Uses for Groundwater Data Analysis

The program uses individual well statistics to prioritize wells in the network and identify locations that have attained cleanup goals. Optimization analyses identify redundant locations using qualitative decision logic and a nearest neighbor spatial geometry approach, estimate plume concentration uncertainty to recommend new well locations, and use a sampling frequency module to recommend optimal sampling intervals.




AFCEC (Air Force Civil Engineer Center). 2012. "Monitoring and Remediation Optimization System (MAROS) Software, User's Guide and Technical Manual." In: Air Force Center for Environmental Excellence.

AFCEE (Air Force Center for Engineering and the Environment).1997. AFCEE Long-Term Monitoring Optimization Guide Version 1.1. Brooks AFB, Brooks City, TX, Air Force Center for Environmental Excellence.

AFCEE. 2004. Monitoring and Remediation Optimization Software User's Guide. Air Force Center for Environmental Excellence. http://www.gsi-net.com/software/MAROS_V2_1Manual.pdf.

Aziz, J. A., C. J. Newell, M. Ling, H. S. Rifai and J. R. Gonzales. 2003. "MAROS:  A Decision Support System for Optimizing Monitoring Plans." Ground Water 41(3): 355-367.

Ling, M., H.S. Rifai, C.J. Newell, J.J. Aziz, and J.R Gonzales. 2003. “Groundwater Monitoring Plans at Small-Scale Sites:  An Innovative Spatial and Temporal Methodology”, Journal of Environmental Monitoring, 5: 126-134.

Ling, M., H. S. Rifai, J. J. Aziz, C. J. Newell, J. R. Gonzales, and J. M. Santillan. 2004a. “Strategies and Decision-Support Tools for optimizing Long-Term Groundwater  Monitoring Plans-MAROS 2.0”, Bioremediation Journal,  8 (3-4): 109-128.

Ling, M., H. S. Rifai, and C. J. Newell. 2004b. "Optimizing Long-Term Monitoring Networks Using Delaunay Triangulation Spatial Analysis Techniques", Environmentrics,  Accepted, August 2004.

Vanderford, M. 2010. "A Comprehensive Approach to Plume Stability." Remediation Winter 2010: 21-37.


Publication Date: December 2013

Permission is granted to refer to or quote from this publication with the customary acknowledgment of the source (see suggested citation and disclaimer).


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