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Software and Tools

Air Quality Models

CMAQ: The Community Multiscale Air Quality Modeling System

The Community Multiscale Air Quality Modeling System (CMAQ) is an active open-source development project that consists of a suite of programs for conducting air quality model simulations. CMAQ combines current knowledge in atmospheric science and air quality modeling, multi-processor computing techniques, and an open-source framework to deliver fast, technically sound estimates of ozone, particulates, toxics and acid deposition.

Other EPA Air Models

Other EPA Air Models and resources include:

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Analytical Method Search Tools

Selected Analytical Methods for Environmental Remediation and Recovery (SAM) 2022

EPA's Selected Analytical Methods for Environmental Remediation and Recovery (SAM) identifies analytical methods to be used by laboratories performing analyses of environmental and building material samples following a contamination event.

National Environmental Methods Index

The National Environmental Methods Index (NEMI) is a searchable database that allows scientists and environmental professionals to find and compare analytical and field methods for all phases of environmental monitoring. Users can perform a general search or filter a search by analyte, chemical, microbiological, population/community, toxicity, statistical, and regulatory.

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Contaminant Fate and Transport Model

SPARROW Modeling Program

SPAtially Referenced Regression on Watershed attributes (SPARROW) is a watershed modeling tool that estimates the amount of a contaminant transported from inland waterbodies to larger water bodies by linking monitoring data with information on watershed characteristics and contaminant sources. Interactive, online SPARROW mapping tools allow for easy access to explore relationships between human activities, natural processes, and contaminant transport.

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Ecological Models

EPA Ecosystem Services Tool Selection Portal

EPA's Ecosystem Services Tool Selection Portal is a resource to help communities incorporate the benefits of local ecosystems into their environmental planning and decision-making. Risk assessors, contaminated site practitioners, or others interested in environmental decision-making can review results from the Portal to learn about various tools that pertain to their specific criteria.

SAS: Software Application for SMASH (Spectral Mixture Analysis for Surveillance of Harmful Algal Blooms)

The Software Application for Spectral Mixture Analysis for Surveillance of Harmful Algal Blooms (SMASH) is an application to facilitate mapping of potentially harmful algal blooms in reservoirs, rivers, and lakes from remotely sensed data. More specifically, SAS is designed to exploit the detailed observations of reflectance available within a hyperspectral image to infer which particular kinds of algae or cyanobacteria might be present within the water body.

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Emergency Response Tools

EPA Emergency Response Tools

Through experiences in the field and site-related activities, EPA's Environmental Response Team (ERT) has determined a need for automating specific manual processes and tasks. As a result, a variety of utilities and tools have been developed to assist OSCs, RPMs, Task Leaders, as well as field personnel in managing and performing their site-related duties. The purpose of this website is to enhance the support service provided to ERT software users. A number of resources are available to help resolve problems, request support, and suggest improvements to ERT products and service.

EPA On-Scene Coordinators Software and Databases

This site is intended to be a tool to help streamline the work of OSCs and provide them a forum to share information and lessons learned with OSCs around the country.

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Environmental Assessment and Analysis Tools

Source History Tool

The Source History Tool was developed for ESTCP's program to help site personnel reconstruct long-term contaminate source histories that extend back to the beginning of the original source release using soil core data collected in low permeability zones.

Spatial Analysis and Decision Assistance (SADA)

Spatial Analysis and Decision Assistance (SADA) is a free software package from the University of Tennessee that integrates modules for visualizing contaminant concentrations, geospatial analysis, statistical analysis, human health risk assessment, cost/benefit analysis, sampling design, and decision analysis. SADA can be used to address site-specific concerns when characterizing a contaminated site, assessing risk, determining the location of future samples, and when designing remedial action.

EPA On-line Tools for Site Assessment Calculation

OnSite was developed to provide modelers and model reviewers with prepackaged tools ("calculators") for performing site assessment calculations. The philosophy behind OnSite is that the convenience of the prepackaged calculators helps provide consistency for simple calculations and access to methods and data that are not commonly available.

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Environmental Data Management Tools

Scribe: Environmental Field Data Capture

Scribe is a software tool developed by EPA's Environmental Response Team (ERT) to assist in the process of managing environmental data. Scribe captures sampling, observational, and monitoring field data. Examples of Scribe field tasks include Soil Sampling, Water Sampling, Air Sampling and Biota Sampling. Scribe can import electronic data including Analytical Lab Result data (EDD) and Sampling Location data such as GPS. Scribe supports handheld extensions, Scriblets, to capture and import sampling and monitoring data collected on handheld PDAs.

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Environmental Impact Tools

Spreadsheets for Environmental Footprint Analysis (SEFA)

EPA developed Spreadsheets for Environmental Footprint Analysis (SEFA), a set of analytical workbooks, to help decision-makers analyze the environmental footprint of a site cleanup project, determine which cleanup activities drive the footprint, and adjust project parameters to reduce the footprint. Information to be input by the user may be gathered from project planning documents, field records and other existing resources. Automated calculations within SEFA generate outputs that quantify 21 metrics corresponding to core elements of a greener cleanup.

Tool for Reduction and Assessment of Chemicals and Other Environmental Impacts (TRACI)

The Tool for Reduction and Assessment of Chemicals and Other Environmental Impacts (TRACI) is an environmental impact assessment tool that provides characterization factors for Life Cycle Impact Assessment (LCIA), industrial ecology, and sustainability metrics and can be applied to processes, products, facilities, companies, and communities.

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Groundwater Flow and Hydrology Models

GFLOW: Groundwater Flow Analytic Element Model

GFLOW is an analytic element model, which solves steady state groundwater flow in a single aquifer. GFLOW supports three-dimensional particle tracking, but employs the Dupuit-Forchheimer approximation, thereby ignoring resistance to vertical flow. GFLOW features a "MODFLOW extract" feature that allows a complete set of MODFLOW files to be written for a subdomain of the model. All aquifer properties and hydrological features are automatically duplicated in the MODFLOW files. Additional features: Areas of differing aquifer properties, horizontal barriers with resistance to flow (slurry walls), 3D flow near a partially penetrating well, local transient flow near a well (Theis solution), steady state interface flow in coastal aquifers, and PEST support for parameter optimalization. GFLOW supports both vector and raster graphics as background maps, including DXF, Shapefile, TIFF, and JPG files.

Mann-Kendall Toolkit

The GSI Mann-Kendall Toolkit is a free, simple, easy-to-use software tool to help environmental professionals efficiently conduct concentration trend analyses for any groundwater constituent. The tool can be used to demonstrate the plume stability condition (expanding, stable, or decreasing) and track the progress of remediation efforts, in a quantitative and consistent manner.

MODFLOW and Related Programs

MODFLOW is a modular hydrologic model and is considered an international standard for simulating and predicting groundwater conditions and groundwater/surface-water interactions. MODFLOW programs are capable of simulating coupled groundwater/surface-water systems, solute transport, variable-density flow (including saltwater), aquifer-system compaction and land subsidence, parameter estimation, and groundwater management.

PHAST - A Computer Program for Simulating Groundwater Flow, Solute Transport, and Multicomponent Geochemical Reactions

PHAST is a computer program that simulates multicomponent, reactive solute transport in three-dimensional saturated groundwater flow systems. PHAST is a versatile groundwater flow and solute-transport simulator capable of modeling a wide range of equilibrium and kinetic geochemical reactions. The flow and transport calculations are based on a modified version of HST3D that is restricted to constant fluid density and constant temperature. The geochemical reactions are simulated with the geochemical model PHREEQC, which is embedded in PHAST.

PHAST can be used in studies of migration of nutrients, inorganic and organic contaminants, and radionuclides; in projects such as aquifer storage and recovery or engineered remediation; and in investigations of the natural rock/water interactions in aquifers.

Geologic Frameworks for Groundwater Flow Models

Groundwater modelers should be familiar with and have access to systematic methods for translating physical subsurface geology into a numerical representation. Other hydrogeologists will benefit from understanding the process. This book introduces techniques for creating the underlying geologic framework of groundwater flow models. It is arranged around a hypothetical site with contaminated groundwater, beginning with a discussion of data collection and geologic interpretation, then delves into the steps required to build a realistic numerical model. The reader will find that many of the methods and calculations can be applied with tools as simple as paper and pencil. Links to publicly available computing resources are provided where possible.

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Groundwater Plume Models and Tools

Matrix Diffusion Toolkit

The Matrix Diffusion Toolkit, developed for the Department of Defense's Environmental Security Technology Certification Program (ESTCP), is a free software tool that can assist site personnel to effectively and efficiently estimate the effects matrix diffusion will have at their site, and share the results with stakeholders. The Toolkit is Microsoft Excel-based and provides the following tools to calculate and evaluate matrix diffusion effects:
  • Square Root Model - this module provides planning-level estimates of the mass discharge (in units of grams per day) caused by release from a low-k diffusion-dominated unit (typically silt or clay) into a high permeability advection-dominated unit (typically sand or gravel).
  • Dandy-Sale Model - this module allows users to perform contaminant transport via advection and transverse diffusion in the transmissive layer, and transport via transverse diffusion in the low-k zone. The module also provides planning-level estimates of the low-k zone and the transmissive zone.
  • Matrix Diffusion Related Tools - Additional tools related to matrix diffusion are provided, including the NAPL Dissolution Calculator, Plume Magnitude Information, Low-k Zone Remediation Alternatives, and a 14-Compartment Model.

FOOTPRINT: A Screening Model for Estimating the Area of a Plume Produced From Gasoline Containing Ethanol

FootPrint is a simple and user-friendly screening model used to estimate the length and surface area of benzene, toluene, ethylbenzene, and xylene (BTEX) plumes in ground water, produced from a spill of gasoline that contains ethanol. Ethanol has a potential negative impact on the natural biodegradation of BTEX compounds in ground water. The primary objective of the software is to predict the increase in surface area of the plume of BTEX compounds or any other chemical of concern (COC) due to the presence of ethanol in ground water. FootPrint estimates the area of a plume of particular BTEX compounds that are contained within two biodegradation zones: 1) a zone that is immediately adjacent to the source, where ethanol is present in high concentration and no biodegradation of the BTEX compounds (or other COC) is allowed, and 2) a second zone, where the ethanol concentration is negligible due to the natural biodegradation of ethanol in the first zone and biodegradation of the BTEX compound (or other COC) contributes to attenuation in concentration of the BTEX compounds. FootPrint is based on the modified version of the Domenico model (1987) published by Martin-Hayden and Robbins (1997). This model is an approximate analytical solution of the advective-dispersive solute transport equation with first-order decay. The model of Martin-Hayden and Robbins (1997) was further modified in FootPrint to allow zero-order decay as well (see Appendix B of the user's manual for details). As a result, FootPrint can independently describe the natural biodegradation of ethanol and/or the BTEX compound with either a zero-order rate constant or a first-order constant. FootPrint can also be used to estimate the surface area of the plume and the concentration at any given point within the plume when the COC is decaying at a constant rate (first- or zero-order) in the absence of ethanol.

Mass Flux Toolkit

The Mass Flux Toolkit, developed for the Department of Defense ESTCP program, is an easy-to-use, software tool that enables users to learn about different mass flux approaches, calculate mass flux from transect data, and apply mass flux values to manage groundwater plumes. The Toolkit presents the user with three main options:
  • a module to calculate the total mass flux across one or more transects of a plume, calculate the uncertainty in the calculation, and plot mass flux vs. distance to show the effect of remediation/impact of natural attenuation processes;
  • a module allowing users to perform critical dilution calculations for plumes approaching production wells or streams. An additional feature calculates the capture zone of the supply well and compares it to the transect used to calculate the mass flux, directing the user to alter the transect dimensions if the transect does not encompass the capture zone; and
  • a module that provides a review of theory and methods of estimating mass flux.

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Model Search Tool

EPA Science Models and Research Tools (SMaRT) Search

SMaRT Search (EPA Science Models and Research Tools) is a searchable database that enables easy access to detailed information about ORD tools as well as instructions on how to download and use them. Features include an easy-to-use simple search that lets you quickly find information, and an advanced search to narrow down by environmental topic area, platform, and scientific application type.

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Models to Assess Exposure

EPA Modeling Products to Assess Exposures

EPA's Center for Exposure Assessment Modeling (CEAM) provides proven predictive exposure assessment techniques for aquatic, terrestrial, and multimedia pathways for organic chemicals and metals.
  • Groundwater Models
    Simulation models and database software designed to quantify the movement and concentration of subsurface contaminants.
  • Surface Water Models
    Simulation models and database software designed to quantify movement and concentration of contaminants in lakes, streams, estuaries, and marine environments.
  • Food Chain Models
    Simulation models and database software designed to determine exposure levels and effects of environmental contaminants on organisms which make up the food chain.
  • Multimedia Models
    These simulation models were designed to quantify the movement and concentration of contaminants traveling through groundwater, surface water, and food chain media.
  • Total Maximum Daily Load (TMDL) Models and Tools
    Simulation models and database software designed to quantify movement and concentration of contaminants in lakes, streams, estuaries, and marine environments.
  • Data Provisioning and Modeling Tools
    Software tools, data, and documents to facilitate exposure assessment.

EPA Fate, Exposure, and Risk Analysis (FERA)

EPA uses a variety of tools to evaluate the health risks and environmental effects associated with exposure to "criteria" air pollutants, including photochemical oxidants, such as ozone, and toxic air pollutants.

Lead at Superfund Sites: Software and Users' Manuals

This website provides access to software and Users' Manuals for the Integrated Exposure Uptake Biokinetic Model for Lead in Children (IEUBK), and the Adult Lead Methodology (ALM).

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Per- and Polyfluoroalkyl Substances (PFAS) Tools

PFAS Analytic Tools

To support EPA's Per- and Poly-Fluoroalkyl (PFAS) Strategic Roadmap, the Agency is compiling and integrating a collection of data that can be used to evaluate what is known about PFAS manufacture, release, and occurrence in communities. As part of this effort, EPA is integrating data available nationally with other information from states, Tribes, and localities that are testing for PFAS pursuant to their own regulatory or voluntary data collection initiatives. The data included in the PFAS Analytic Tools have a wide range of location-specific data and, in general, are based on national scope, and readily accessible, public information repositories.

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Planning Tools


AMDTreat 6.0 Beta is a computer application for estimating the long-term costs of the abatement of mine drainage discharge, commonly referred to as Acid Mine Drainage (AMD). AMDTreat 6.0 Beta can assist a user in estimating costs and sizing facilities to abate water pollution, using passive or chemical treatment technologies. Treatment systems, vertical flow ponds, anoxic limestone drains, anaerobic wetlands, bioreactors, caustic soda, hydrated lime, pebble quicklime, soda ash treatment and other systems can be evaluated.

HRS Quickscore

HRS Quickscore was created to assist in scoring sites using EPA's Hazard Ranking System (HRS). HRS Quickscore is an electronic set of HRS scoresheets that executes real time site score calculations. It was designed to assist in developing a conceptual site model for Superfund site assessments. This product is intended for use by those individuals who plan and implement Preliminary Assessments (PAs), Site Inspections (SIs), and other data collection efforts according to the HRS rules, as well as those individuals that write and review HRS documentation records.

Federal Remediation Technologies Roundtable Decision Support Tools (DSTs) Matrix

DSTs are interactive software tools used by decision-makers to help answer questions, solve problems, and support or refute conclusions. They can be incorporated into a structured decision-making process for environment site clean-up. DSTs often support multiple functions, such as data acquisition, spatial data management, modeling, and cost estimating. The Federal Remediation Technologies Roundtable matrix is a table that provides general information about each DST, such as the types of files that may be imported to, or exported from, the DST, the characteristics of applicable sites (contaminants and media) and the functions it performs. All DSTs that were evaluated are free to the public.

ProUCL Software

ProUCL is a comprehensive free statistical software package with statistical methods and graphical tools to address many environmental sampling and statistical issues. EPA regions, states, contractors, and and other stakeholders use ProUCL to establish background levels, determine outliers in data sets, and compare background and site sample data sets for site evaluation and risk assessment.

Pacific Northwest National Laboratory Visual Sample Plan (VSP) Software

This beta version software package is downloadable free of charge. The software assists development of cost-effective, statistically-based sampling plans, and is is applicable for any two-dimensional sampling plan. VSP calculates the number of samples under various scenarios, includes cost considerations, and provides random or gridded sampling locations for overlay on a site map. The website also provides training information and links to other sites that provide software for use in contaminated site cleanup.

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Remediation System Tools

Monitoring and Remediation Optimization System (MAROS)

The Monitoring and Remediation Optimization System (MAROS) software has been developed by Groundwater Services Inc. and the University of Houston for the Air Force Center for Engineering and the Environment (AFCEE) in accordance with the AFCEE Long-Term Monitoring Optimization guide. The software provides site managers with a strategy for formulating appropriate long-term groundwater monitoring programs that can be implemented at lower costs. MAROS is a decision support tool based on statistical methods applied to site-specific data that accounts for relevant current and historical site data as well as hydrogeologic factors (e.g. seepage velocity) and the location of potential receptors (e.g., wells, discharge points, or property boundaries). Based on this site-specific information the software suggests an optimization plan for the current monitoring system in order to efficiently achieve the termination of the monitoring program.

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Technology Screening Tools

FRTR Technology Screening Matrix

The Federal Remediation Technologies Roundtable (FRTR) Matrix is a user-friendly tool for screening potentially applicable technologies for a remediation project. The matrix allows you to screen 49 in situ and ex situ technologies for either soil or groundwater remediation. Variables used in screening include contaminants, development status, overall cost, and cleanup time. Detailed information on each technology is also available, including direct links to the database of cost and performance reports written by FRTR members.

BioPIC Tool for the Selection of Bioremediation Approaches at Chlorinated Solvent Sites

The Department of Defense's (DoD) Environmental Security Technology Certification Program (ESTCP) has developed an easy-to-use tool called BioPIC to facilitate bioremediation decision-making based on site-specific physical and biogeochemical characteristics. This research project determined the relationship between biogeochemical parameters and degradation rates for known degradation pathways of chlorinated ethenes (primarily PCE, TCE, and daughter products). Data from 90+ sites was used to establish correlations between the naturally attained rate constant and the abundance of specific parameters. Associations were then established for parameters such as Dehalococcoides (Dhc) densities, reductase densities, dissolved oxygen, oxidation-reduction potential, magnetic susceptibility, Fe(II), Mn(II), methane, ethane, total organic carbon, and others. These associations were used to develop a quantitative framework and decision logic for the screening tool. Based on site-specific conditions, the tool will provide screening considerations to determine if monitored natural attenuation (MNA), biostimulation, biologically mediated abiotic reductive dechlorination, or bioaugmentation is the most appropriate remedial approach.

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Vapor Intrusion Models and Tools

EPA Spreadsheet for Modeling Subsurface Vapor Intrusion (Johnson and Ettinger Model Spreadsheet Tool, Version 6.0)

This website provides an updated spreadsheet tool developed by the EPA for estimating indoor air concentrations and associated health risks from subsurface vapor intrusion into buildings. The tool is based on the analytical solutions of Johnson and Ettinger for contaminant partitioning and subsurface vapor transport into buildings.

Vapor Intrusion Screening Level Calculator

The Vapor Intrusion Screening Level (VISL) calculator identifies chemicals that are considered to be sufficiently volatile and toxic to warrant an investigation of the soil gas intrusion pathway when they are present as subsurface contaminants. The calculator provides generally recommended, media-specific, risk-based screening-level concentrations for groundwater, near-source soil gas, sub-slab soil gas, and indoor air. These screening-level concentrations (i.e., the VISLs) are based on default residential or nonresidential exposure scenarios, a target cancer risk level of one per million, and a target hazard quotient of 0.1 for potential non-cancer effects.

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