Approximate Cost: Free

Source:  Request from Philip Hunter, AFCEC (formerly AFCEE), [email protected], or John Hicks, Parsons, [email protected]

Current Version: v1.0

Operating System Needs: Windows XP Service Pack 3, Windows Vista, Windows 7

Input Structure: Microsoft Excel spreadsheet or comma-separated values (CSV) file


The 3-Tiered Monitoring Optimization Tool (3TMO) was developed by Parsons and ENVIRON International Corp. on behalf of Air Force Civil Engineer Center (AFCEC), known previously as Air Force Center for Engineering and the Environment (AFCEE), in 2011. This program is a comprehensive, public domain, user-friendly, long-term monitoring optimization (LTMO) decision support tool. Across the spectrum of monitoring approaches, this tool emphasizes the qualitative and intuitive aspects of optimization. The program offers more efficient performance and successful implementation of LTMO evaluations. In addition, 3TMO presents guidance for other aspects of monitoring programs, including use of passive or low-flow sampling methods, sample shipment, purge water disposal, field quality assurance/quality control samples, and data management. This program incorporates substantive qualitative considerations into the analysis, and output can be augmented by user-entered considerations and rationale. 

Add-Ins Available


Ease of Use and Data Import

3TMO3-Tiered Monitoring Optimization Tool applies user input for project information, well parameters, contaminants, and sample data. Enter tabular data directly into the data input grids or import information from correctly formatted Excel or CSVcomma-separated values files. Enter other data through the functions accessible from the Data Input submenu on the Framework Overview home page or from the LTMO Framework menu links. Well parameters must be loaded before sample data; the sample data well IDs must be entered into the Well Parameters table before they can be successfully loaded. Example data input files are available from the Help menu, Example Project link, and can be used as templates for creating site-specific data upload files.

The 3-Tiered approach is sufficiently sophisticated, comprehensive, and rigorous to yield credible and useful results, yet at the same time it is intuitive and easy to understand. The spatial analysis that 3TMO3-Tiered Monitoring Optimization Tool offers is a relatively straightforward qualitative analysis that can be performed to evaluate the spatial importance of monitoring locations using the Map Tool.

Types of Distribution

The Mann-Kendall test for trends is included in 3TMO3-Tiered Monitoring Optimization Tool which is a nonparametricStatistical test that does not depend on knowledge of the distribution of the sampled population (Unified Guidance). trend test. The software does not include tests to determine the distribution of the data (such as normal, lognormalA dataset that is not normally distributed (symmetric bell-shaped curve) but that can be transformed using a natural logarithm so that the data set can be evaluated using a normal-theory test (Unified Guidance).).


Results of statistical analyses can be exported to Excel for formatting to a user-defined specification.

Primary Uses for Groundwater Data Analysis

This public domain software tool supports LTMOlong term monitoring optimization evaluations at the groundwater contaminant plume or site level (not on an installation-wide basis). The tool is intended for use by environmental managers, contractors, and regulators at sites of varying size and complexity, and is scalable dependent on the available level of information. It provides a credible alternative for sites where LTMO practitioners must incorporate a substantial qualitative evaluation into the overall LTMO analysis. Although the tool was designed for optimization of groundwater monitoring networks, portions of it could conceivably also be used to assess surface water monitoring networks (such as temporal trend evaluation and spatial evaluation).


Limitations and Data Requirements


Nobel, C. and Anthony, J.A. 2004. "Three-Tiered Approach to Long-Term Monitoring Program Optimization." Bioremediation Journal 8 (3-4): 147-165.


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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