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Environmental Modeling Community of Practice

Exposure Assessment Models Recent Additions

Listed below are some of the recent additions and updates available on the Exposure Assessment Models Web site maintained by the EPA Center for Exposure Assessment Modeling (CEAM). To receive e-mail notification of additions and updates, you may subscribe to the CEAM discussion listserv.

October 2020

WMOST Additions

An updated version 2 of the Hydroprocessor for WMOST was added with an associated user guide.  The Hydroprocessor allows the user to process outputs from SWAT and HSPF files for use in WMOST.  Version 2 includes updates to ensure compatibility with SWAT models created in HAWQS.

A report on a new case study based on WMOST v 3.01 was added. A case study application of EPA’s Watershed Management Optimization Support Tool (WMOST v3.01) was carried out to inform management options for the heavily urbanized watershed of Cabin John Creek (CJC), MD, a tributary to the Potomac River, for the 10-year period 2014 - 2025. CJC was chosen as a representative case study of a watershed required to meet loading targets for both the Chesapeake Bay Total Maximum Daily Load (TMDL) as well as a Maryland nontidal stream TMDL for total suspended solids (TSS), but without water supply constraints.

A new Benefits Module with user guide and theoretical documentation were added. The new Benefits Module for WMOST embedded within ScenCompare v. 2 enables stakeholders to calculate the value of additional water quality benefits associated with water resource management as well as additional co-benefits. Water quality benefits (or costs) include both changes in costs of drinking water treatment and total nonmarket benefits (i.e., use and nonuse) of water quality changes. Co-benefits valued include (1) change in housing property value due to improved aesthetic quality of the landscape from increases in green space, (2) air pollution removal and energy savings benefits related to canopy cover, and (3) air pollution removal and energy savings benefits related to green roofs.

October 2019

Hydrologic Micro Services was added:

CEAM developed a hydro-informatics platform called Hydrologic Micro Services (HMS) to address the importance of interoperability, transparency,  reproducibility, and efficiency in environmental modeling.

The HMS platform is a collection of hydrologic and water quality data provisioning web services and modeling components. HMS data provisioning web services purvey raw data through online script requests for hydrologic parameters including precipitation, air temperature, solar radiation, soil moisture, evapotranspiration, surface and subsurface flow, and runoff. A component is a distinct software module that the user can incorporate and link into existing models.

June 2019

WMOST version 3.01 was updated:

WMOST v3.01 Changes Made to Version 3.0:

Implemented by EPA

  • Options file addition – The optimization module now creates an options file for NEOS optimization runs which allows the user to change settings for the maximum number of iterations from the default of 3000 up to a maximum of 10000 and for the tolerance value of the cost objective function (0.0001 is recommended).  The tolerance value determines how (relatively) close the final solution has to be to the optimum.
  • Loading units option for metric tonnes – This option allows users to enter loading time series for suspended sediment in metric tonnes/time step instead of pounds/time step.  To facilitate optimization algorithms, decision variables should be of similar magnitude in the region of interest (near the solution).  Ideally a unit change in any variable should produce a unit change in the objective function.  NEOS has some preconditioning routines to handle scaling but can’t always resolve problems (See https://www.solver.com/standard-excel-solver-problems-poorly-scaled-models, http://www.math.uwaterloo.ca/~hwolkowi//henry/reports/talks.d/t09talks.d/09waterloomatlab.d/optimTipsWebinar/html/optimTipsTricksWalkthrough.html#40) for more discussion of this issue.  Initial runs of WMOST v3 to optimize management for total suspended sediments tended to run into scaling problems. Changing the units of loading time series for TSS from pounds/time step to metric tonnes/time step helped to make optimizations run more efficiently for TSS.
  • Annual load target option – An option to set annual load targets instead of daily loading targets was added.
  • Fixed look-up table vulnerability
    • Previously look-up tables for dropdown lists were incorporated to the right of the portion of each WMOST tab used for entering data with font color set to white
    • Font color of look-up tables for drop down lists was changed to red boldface and associated columns are now hidden.  A warning message was added at the top of the look-up tables to prevent the user from deleting or modifying these lists.
  • ScenCompare Utility was added.

Implemented by Abt

  • Replaced Optimize button (it was corrupted, leading to the optimize error and crashing)
  • Changed where precipitation and temperature statistics are calculated from
    • Previously, precipitation was calculated from the “Precipitation” sheet and temperature was calculated from the “Stormwater-Data” sheet. This lead to issues when a user skipped processing the data for either tab.
    • Now, precipitation and temperature are calculated from the “Hydro_Stage” hidden tab, which is populated whenever a user uses the baseline hydrology module. If a user does not use the module, they need to calculate their climate statistics separately.
  • Corrected issue with pulling the flows needed for the Graphs module on the Lookup Tables tab
    • The flows were coming from an external tab, but the lookup formula was pulling a cell from the lookup tab
  • Added a conversion in the Graphs module
    • The flow from SW to external is graphed in the Graphs module and was missing a conversion from MGD to cfs for the graph
  • Changes to the Scenario Log File macro
    • Removed if statements that only printed stormwater data if it was present in order to make the log files the same length whether a user used the stormwater module or not.
    • Changed order of stormwater data (put stormwater land use sets before the stormwater module data)
    • Revised code that added the HRU ID from the hydrology databases (change primarily made for v3.1 for HCAM application, but applied to v3 to minimize differences in log files between the two versions).
  • Corrected calculation of fit statistics on Calibration tab
    • Previously if there were missing values in measured time series, this introduced errors into the calculation of fit statistics
    • The form of formulas was changed to eliminate errors due to missing values
  • Corrected reporting of total cost on Results tab
    • Occasionally, total costs were incorrectly reported on the Results tab even though component costs were reported correctly
    • Simplified reporting of total cost by adding code to include an extra “display cost” command in the Wcommand.amp file which generates an explicit listing of the final objective value (cost = nnn.nn) that can be easily recognized by code in the Results Module.

May 2019

WASP 8.32 was updated:

WASP 8.32 includes the following enhancements:

  • Corrected Issue associated with Phosphorus Flux to SOD Module
  • Corrected Flow Routing Transport Option
  • Cleanup Interface Database
  • Updated Output Routines
  • Added New Output File Containing Major Fluxes
  • Enhanced the Import Routine for WASP7 Files to include periphyton
  • Organic Chemical/Nano Chemical and Solids/Nano Solids model is complete
  • Updated precision in sediment transport algorithm
  • Enhanced the Toxicant Model BMD Output
  • Updated timestep optimization routine to include settling
  • Add option for setting timestep optimization sensitivity for adjustment
  • Updated analytical solution for solids settling
  • Fixed issue with POC Decay Derivative Calculation
  • Re-worked how external data links are refreshed
  • Added Segment Meta Data File for BMD Output Files

February 2019

Virtual Beach version 3.0.7 was updated:

VB 3.0.7 Enhancements Include:

  • Added plotting capabilities on the MLR modeling tab - users can visualize P(exceedance) for either model fits or predictions
  • Delete directory call is now forced
  • Fixed an io error when closing the software
  • Changed the GBM/PLS plotting methods to allow plotting of both dates and strings in the datasheet ID column (column 1)

October 2018

DFLOW was added:

DFLOW is a Windows-based tool developed to estimate user selected design stream flows for low flow analysis and water quality standards. This latest version can be readily used by regulators in state and EPA regional offices, modelers, or anyone else interested in calculating design flow statistics.

The Definition and Characteristics of Low Flows was added:

This page provides background information on the definition and characteristics of low flows, the relationship between low flows  and aquatic life criteria and design flows.

September 2018

The AQUATOX model was updated:

version 3.2

AQUATOX 3.2 includes the following interface enhancements:

  • Update to AQUATOX Database Management System:  The paradox database management system (used in previous versions) has been replaced with SQLite databases.   
  • Capability to save all inputs and outputs to a text file:  AQUATOX now can write all model inputs and outputs in ASCII format by saving files with a “*.txt” extension.  This allows users to view and change model inputs without using the graphical user interface.
  • Command Line Version:  Users may now execute and manipulate the model using a DOS command prompt.  
  • For information about how to use each of these interface updates, please see the Release 3.2 User’s Manual.

In addition to the changes discussed above, changes were made to the model to represent the “nearshore marine environment” as discussed here.

Nearshore Marine Environment

AQUATOX Release 3.2 was designed to extend the existing AQUATOX estuarine version to include improved capabilities for situations encountered in the nearshore marine environment. Several changes were required to model food webs in the marine environment.  The most notable updates include:

  • Additional equations to model the physical complexity of oyster reefs and the marsh-edge environment.
  • The capability to model size-classes of oysters and crabs within the model.
  • New invertebrate-modeling capabilities including allometric bioenergetics equations and burrowing refuge from predation.  
  • To better represent marine-biology conventions, the guilds used by AQUATOX to characterize these state variables were reorganized.
  • Four new nearshore-marine studies are included in this version representing “marsh edge,” “exposed beach,” “soft bottom,” and “oyster reef” habitats.  Numerous nearshore-marine animal- and plant-parameter records have been added to the AQUATOX databases.
  • For full details about these changes please see the AQUATOX Release 3.2 Technical Documentation.

July 2018

The GCSOLAR model was published:

version 1.0 July 2018

  •  This release (1.0 July 2018) of the GCSolar program differs from earlier versions of the program in that it is written in C# whereas the previous versions were written in FORTRAN. 
  • This version also permits the user to interact with the application using graphical user interface.

June 2018

The Wellhead Analytic Element Model (WhAEM)  was updated:

version 3.3.2

Major CHANGES BETWEEN VERSIONS 3.2.1 and 3.3.2.

  • The WhAEM installation folder structure has been modified to be compatible with the security requirements of the latest Windows operating systems. The application folder now only contains executables and no files will be written to this folder. The user application data folder contains the various documents associated with WhAEM and the WhAEM help system. The WhAEM projects are stored in the My Documents folder. Additionally, the file written by "contour.exe" is now deleted and recreated for each new contour set. This is to overcome read-only security settings.
  • Base maps in WhAEM are managed by ESRI's MapObject LT 2 and reprojections have been removed from the Tools menu in WhAEM. The user will be responsible for all map management using state-of-the-art GIS software. Additionally, the BBM Base Map Browser has also been removed from the Tools menu.  The user can access BBM files from an EPA website as explained in the WhAEM Help system. 3. The WinHelp system for WhAEM has been replaced by an updated HTML Help system. The HTML Help system is fully compatible with all newer Windows operating systems.
  •  

May 2018

The Water Quality Analysis Simulation Program (WASP) was updated:

version 8.1

  • Corrected Issue associated with Phosphorus Flux to SOD Module
  • Corrected Flow Routing Transport Option
  • Cleanup Interface Database
  • Updated Output Routines
  • Added New Output File Containing Major Fluxes
  • Enhanced the Import Routine for WASP7 Files to include periphyton
  • Organic Chemical/Nano Chemical and Solids/Nano Solids model is complete

February 2018

The Watershed Management Optimization Support Tool (WMOST) v3.0 has been  added to the CEAM website. WMOST is a decision support tool that facilitates integrated water management at the local or small watershed scale. Integrated water management involves coordination across multiple programs for land, water, and related resources (stormwater, wastewater, drinking water, land conservation) to find sustainable and cost-effective solutions.

May 2016

The Model Performance Evaluation and Scenario Analysis (MPESA) Tool was developed to provide users with the ability to assess the performance with which models predict time series data (e.g., streamflow). The tool was developed specifically for the Hydrological Simulation Program-Fortran (HSPF) and the Stormwater Management Model (SWMM) models.

March 2016

Watershed Management Optimization Support Tool (WMOST) v2 has been added to the CEAM site. The Watershed Management Optimization Support Tool (WMOST) is a decision support tool that evaluates the relative cost-effectiveness of management practices at the local or watershed scale. WMOST models the environmental effects and costs of management decisions in a watershed context, which is, accounting for the direct and indirect effects of decisions.

February 2016

Virtual Beach version 3.0.6 (VB3.0.6) has been added to the CEAM site.  Virtual Beach facilitates the development of statistical models of pathogen indicator levels at recreational beaches.

October 2015

Better Assessment Science Integrating Point and Nonpoint Sources (BASINS) is a multipurpose environmental analysis system designed to help regional, state, and local agencies perform watershed- and water quality-based studies.

September 2015

  • A new tool that allows users to combine GRAY and GREEN Tool calculations when
    building complex FTABLES has been added in the HSPF BMP Toolkit. Using this
    tool, HSPF users can build FTABLES and paste it on to User Control Input (UCI)
    file. The FTABLE builder generated FTABLES should not create formatting
    problems when pasted on to a UCI file..
  • The Gray Infrastructure Tool has the following features
    • Natural channel with flood plain panel added
    • Default depth increment of 0.5 is used for Natural Channel with FP
    • Units option added – SI or US units. Default option is US units
    • Conversion options added wherever necessary
    • Additional options added to FTABLE such as clear FTABLE
    • Significant digits for FTABLE calculations is changed to 4
    • Previously a default Cd value is used for calculations (under-drain and riser) but now a user defined value is used  
    • Default values of Cd for riser orifice and under-drain textboxes is changed to 0.6
    • Previously a default increment value of 0.1 is used for all the channel panels but now user can specify the increment
  • The Green Infrastructure Tool has the following features
    • Units option added – SI or US units. Default option is US units
    • Additional options added to FTABLE such as clear FTABLE
    • Significant digits for FTABLE calculations is changed to 5
    • Previously a default Cd value was used for calculations (under-drain and riser) but now a user-defined value option is given
    • Conversion options added wherever necessary
    • Default values of suction head and hydraulic conductivity are changed based on units selected in infiltration panel
    • Default values of Cd for riser orifice and under-drain textboxes is changed to 0.6.
    • Previously a default increment value of 0.1 is used for all the channel panels but now user can specify the increment
  • HYDROLOGICAL SIMULATION PROGRAM – FORTRAN (HSPF) DATA FORMATTING TOOL (HDFT)
    • Because HSPF requires extensive input data, the HSPF Data-Formatting Tool (HDFT) allows users to format model input data and import it into a WDM file. This tool is also for users who are building their data from scratch from study areas outside of the United States. HDFT aids HSPF’s GRAY and GREEN infrastructure modeling applications that use sub-hourly temporal resolutions. GRAY infrastructure is most often used in urban environments where stormwater usually flows into stormwater system pipes before reaching a local stream, lake, or wastewater treatment plant. GREEN infrastructure systems mimic natural processes to infiltrate, evaporate, and/or reuse stormwater to maintain the pre-development hydrology and water quality of urban environments.

August 2015

  • The Water Quality Analysis Simulation Program (WASP) version 7 is an enhancement of the original WASP (Di Toro et al., 1983; Connolly and Winfield, 1984; Ambrose, R.B. et al., 1988). This model helps users interpret and predict water quality responses to natural phenomena and manmade pollution for various pollution management decisions. WASP is a dynamic compartment-modeling program for aquatic systems, including both the water column and the underlying benthos. WASP allows the user to investigate 1, 2, and 3 dimensional systems, and a variety of pollutant types. The state variables for the given modules are given in the table below. The time varying processes of advection, dispersion, point and diffuse mass loading and boundary exchange are represented in the model. WASP also can be linked with hydrodynamic and sediment transport models that can provide flows, depths velocities, temperature, salinity and sediment fluxes. This release of WASP contains the inclusion of the sediment diagenesis model linked to the Advanced Eutrophication sub model, which predicted sediment oxygen demand and nutrient fluxes from the underlying sediments.
  • The Desktop HDFT is a tool for converting Time Series Data from character delimited file formats to formats compatible with other scientific applications.

July 2015

The Model Performance Evaluation and Scenario Analysis (MPESA) Tool was developed to provide users with the ability to assess the performance with which models predict time series data (e.g., streamflow). The tool was developed specifically for the Hydrological Simulation Program-Fortran (HSPF) and the Stormwater Management Model (SWMM) models, other models can also use it if they generate time series output data.

June 2015

The Evapotranspiration Calculator estimates evapotranspiration time series data for hydrological and water quality models. The tool was developed specifically for the Hydrologic Simulation Program - Fortran (HSPF) and the Stormwater Management Model (SWMM), but can be used with other models if they use time series ET data as input.

March 2014

The AQUATOX Ecosystem simulation model version 3.1 has been added to the CEAM site.  AQUATOX is an ecosystem simulation model that predicts the fate of various pollutants, such as excess nutrients and organic chemicals, and their effects on aquatic ecosystems, including fish, invertebrates, and aquatic plants. AQUATOX is a valuable tool for ecologists, biologists, water quality modelers, and anyone who performs ecological risk assessments for aquatic ecosystems. EPA has just released an enhanced version of AQUATOX, Release 3.1, which includes many model interface enhancements and some conceptual model refinements.

December 2013

  • Watershed Management Optimization Support Tool WMOST version 1.0 has been added to the CEAM site.  WMOST is intended to be used as a screening tool as part of an integrated watershed management process such as that described in EPA’s watershed planning handbook (EPA 2008).1 The objective of WMOST is to serve as a public-domain, efficient, and user-friendly tool for local water resources managers and planners to screen a wide-range of potential water resources management options across their watershed or jurisdiction for cost-effectiveness as well as environmental and economic sustainability (Zoltay et al 2010).
  • Published a modification to Virtual Beach version 3.0 (Virtual Beach version 3.0).

September 2013

  • Virtual Beach version 3.0 (Virtual Beach version 3.0) has been added to the CEAM site.  Virtual Beach facilitates the development of statistical models of pathogen indicator levels at recreational beaches. VB3.0 reads input data from a text or Excel file, assists the user in preparing the data for statistical analysis, and provides three analytical techniques for model development:  multiple linear regression (MLR), partial least squares regression (PLS), and a gradient boosting machine (GBM).  With an integrated mapping component to determine the geographic orientation of the beach, the software can automatically decompose wind/current speed and direction into along-shore and onshore/offshore components.  VB3.0 can produce new variables from sets of variables in the input file (e.g., means, minimums, maximums, differences, sums, products), and it can test an array of transformations on the independent variables to maximize the linearity of the relationship between the response and those independent variables.  In the MLR module, automated censoring of models with a high degree of multi-colinearity occurs during the selection process. The PLS and GBM modules institute 5-fold cross-validation during model development to avoid over specification.  The prediction module of VB3.0 has a direct link to the USGS EnDDaT system to automatically retrieve data for beach sites in the Great Lakes region.

September 2010

  • CEAM has posted a new application, Virtual Beach. Virtual Beach version 2.0 (VB2.0) is a software package designed to construct site specific Multi-Linear Regression (MLR) models for the prediction of pathogen indicator levels at recreational beaches. VB2.0 reads input data from a text file or Excel document, assists the user in preparing the data for a multiple linear regression (MLR) analysis, enables automated model selection using a wide array of possible model evaluation criteria, and provides predictions using a chosen model and new observational data. With an integrated mapping component to determine the geographic orientation of the beach, the software can automatically decompose wind/current speed and direction into along-shore and onshore/offshore components for later analysis. Data can be examined visually using simple scatterplots to gage relationships between the response and independent variables. VB2.0 can quickly produce second-order interaction terms between main effects, and it can also test an array of transformations on the independent variables in order to maximize the linearity of the relationship between the response and those independent variables. The software includes exhaustive and genetic algorithm (GA) search routines for finding the "best" models from a large array of possible choices. Automated censoring of models with a high degree of multicollinearity (large Variance Inflation Factor) occurs during the selection process. Models can be constructed either using previously collected or forecasted environmental data.

August 2010

  • CEAM has posted an updated version of the Watershed Health Assessment Tools Investigating Fisheries (WHATIF). WHATIF v3.1 incorporates an expanded and enhanced toolset that encompasses regional EMAP data of Mobile Bay Estuary, Alabama that extends WHATIF's geographical domain. WHATIFv3.1 incorporates a new general purpose query tool the Database Exploration Tool, with the output being site data records that match the query. Also a new Mobile Bay Fish Assemblage Predictor tool, species relative abundance based, is included in WHATIFv3.1 that allows a user to predict a fish assemblage at a location of interest based on characteristics of that location.

January 2009

  • CEAM has posted an updated version of the Web-based Interspecies Correlation Estimation (Web-ICE) application. The Web-ICE Species Sensitivity Distribution (SSD) modules have been updated to include selection of multiple surrogate species. Web-ICE generates an SSD from the combined estimated toxicity values of all predicted species for all surrogate species (maximum of 25 surrogates), which are use to predict toxicity hazard levels. The modules include a new option to show additional information for each predicted toxicity value, such as surrogate species, degrees of freedom, model R2, p-value, mean square error, cross-validation success rate, and taxonomic distance.

March 2008

  • CEAM has posted an updated Microsoft Excel 2003 based model, SERAFM (Spreadsheet-based Ecological Risk Assessment for the Fate of Mercury). SERAFM is a process-based, steady-state modeling system incorporating a series of process modules that predict speciated mercury concentrations (Hg0, HgII, MeHg, HgT) in water (filtered and unfiltered) and sediments, and total mercury concentrations in fish tissue.
  • Please refer to the release notes for a detailed list of releases and changes.

March 2008

  • CEAM has posted an updated Microsoft Excel 2003 based model, SERAFM (Spreadsheet-based Ecological Risk Assessment for the Fate of Mercury). SERAFM is a process-based, steady-state modeling system incorporating a series of process modules that predict speciated mercury concentrations (Hg0, HgII, MeHg, HgT) in water (filtered and unfiltered) and sediments, and total mercury concentrations in fish tissue.
  • Please refer to the release notes for a detailed list of releases and changes.

March 2008

  • The Bioaccumulation and Aquatic System Simulator (BASS) has been posted on CEAM. BASS is a model that simulates the population and bioaccumulation dynamics of age-structured fish communities.
  • BASS has be used to:
    • investigate the bioaccumulation of chemical pollutants within a community or ecosystem
    • explore population and community dynamics of fish assemblages that are exposed to a variety of nonchemical stressors such as altered thermal regimes associated with hydrological alterations or industrial activities, commercial or sports fisheries, and introductions of non native or exotic fish species.

September 2007

  • An updated version of the U.S. EPA's Wellhead Analytic Element Model, Wellhead Analytic Element Model (WhAEM) WHAEM2000, has been posted on the CEAM web site. WhAEM2000 for Windows (98/NT/2K/XP), is a groundwater flow model designed to facilitate capture zone delineation and protection area mapping.
  • A detailed list of changes is available in the release notes.

September 2007

  • The Environmental Fluid Dynamics Code (EFDC) has been posted on CEAM. EFDC is a multifunctional surface water modeling system which includes hydrodynamic, sediment-contaminant, and eutrophication components.
  • EFDC has be used to:
    • study high fresh water inflow events in the northern portion of the Indian River Lagoon, Florida
    • model flow through high vegetation density-controlled wetland systems in the Florida Everglades.
    • discharge dilution studies in the Potomac, James and York Rivers.
    • salinity intrusion studies include the York River, Indian River Lagoon and Lake Worth.
    • sediment transport studies include the Blackstone River, James River, Lake Okeechobee, Mobile Bay, Morro Bay, San Francisco Bay, Elliott Bay - Lower Duwamish Waterway, and Stephens Passage.
    • power plant cooling studies include Conowingo Reservoir, the James River and Nan Wan Bay.
    • contaminant transport and fate studies include the Blackstone and Housatonic Rivers, James River, San Francisco Bay, and Elliott Bay - Lower Duwamish Waterway.
    • water quality eutrophication studies include Norwalk Harbor, Peconic Bay, the Christina River Basin, the Neuse River, Mobile Bay, the Yazoo River Basin, Arroyo Colorado, Armand Bayou, Tenkiller Reservoir, and South Puget Sound.

August 2007

  • CEAM has posted an updated version of the Web-based Interspecies Correlation Estimation (Web-ICE). Web-ICE estimates the acute toxicity of a chemical to a taxon (i.e., the predicted species, genera, or family) without test data from the known toxicity of the chemical to a species with test data (the surrogate).
  • WebICE now provides expanded functionality for aquatic taxa models and sensitivity distributions.
  • A JavaScript-enabled web browser is required to operated Web-ICE.

August 2007

  • The EXAMS - PRZM Exposure Simulation Shell (EXPRESS) model has been updated and posted on CEAM. EXPRESS is designed to facilitate a rapid and consistent assessment of aquatic pesticide exposure on a variety of crops. EXPRESS is a joint project of the USEPA Office of Pesticide Programs' Environmental Fate and Effects Division (OPP/EFED) and the USEPA Office of Research and Development (ORD). A detailed list of changes is available in the release notes.

May 2007

  • Web-based Interspecies Correlation Estimation (Web-ICE) has been posted on CEAM. Web-ICE estimates the acute toxicity of a chemical to a taxon (i.e., the predicted species, genera, or family) without test data from the known toxicity of the chemical to a species with test data (the surrogate). ICE models are least square regressions between the surrogate species and the predicted taxa to estimate the toxicity of that chemical to the predicted species, genus or family. Web-ICE replaces the desktop application, ICE. A JavaScript-enabled web browser is required to operated Web-ICE.
  • Web-ICE can be used to:
    • Predict toxicity to wildlife taxa.
    • Generate Species Sensitivity Distributions.

April 2007

  • CEAM has posted a new ecosystem assessment tool, Watershed Health Assessment Tools Investigating Fisheries (WHATIF). WHATIF is software that integrates a number of calculators, tools, and models for assessing the health of watersheds and streams with an emphasis on fish communities in the Mid-Atlantic Highland region. The tool set consists of hydrologic and stream geometry calculators, a fish assemblage predictor, a fish habitat suitability calculator, macro-invertebrate biodiversity calculators, and a process-based model to predict biomass dynamics of stream biota (the BASS model).
  • These models can be used to:
    • Watershed health assessment.
    • Prediction of stream hydraulic geometry based on mean annual flow conditions.
    • Prediction of stream hydraulic geometry based on Bankfull flow conditions.
    • Prediction of fish habitat suitability.
    • Prediction of fish assemblage.
    • Prediction of macro-invertebrate biodiversity (EPT and MBII).
    • Simulation of bio-accumulation.
    • Investigate sensitivity of processes and model parameters.
    • Screening analysis, such as prioritization of areas for restoration and comparison of alternative watershed and habitat management scenarios.

February 2007

  • CEAM has re-posted the 3DFEMWATER/3DLEWASTE models (source code only). 3DFEMWATER/3DLEWASTE, Three-Dimensional Finite Element Model of Water Flow Through Saturated-Unsaturated Media (3DFEMWATER) and Three-Dimensional Lagrangian-Eulerian Finite Element Model of Waste Transport Through Saturated-Unsaturated Media (3DLEWASTE) are related and can be used together to model flow and transport in three dimensional, variably-saturated porous media under transient conditions with multiple distributed and point sources/sinks.
  • These models can be used to apply the assimilative capacity criterion to development of wellhead protection areas. A detailed list of changes is available in the release notes.

October 2006

  • CEAM has posted a new Microsoft Excel 2003 based model, SERAFM (Spreadsheet-based Ecological Risk Assessment for the Fate of Mercury). SERAFM is a process-based, steady-state modeling system incorporating a series of process modules that predict speciated mercury concentrations (Hg0, HgII, MeHg, HgT) in water (filtered and unfiltered) and sediments, and total mercury concentrations in fish tissue.
  • SERAFM was specifically developed to serve as a screening-level tool to investigate mercury cycling and exposure concentrations in water bodies and associated impacted wildlife exposure risk, as well as a research tool to investigate mercury processes within the watershed and water body.

October 2006

  • CEAM has updated the EXPRESS model (EXAMS - PRZM Exposure Simulation Shell). EXPRESS is designed to facilitate a rapid and consistent assessment of aquatic pesticide exposure on a variety of crops. EXPRESS is a joint project of the USEPA Office of Pesticide Programs' Environmental Fate and Effects Division (OPP/EFED) and the USEPA Office of Research and Development (ORD). A detailed list of changes is available in the release notes.

May 2006

  • CEAM has updated the PRZM3. PRZM3 is the most recent version of a modeling system that links two subordinate models, PRZM and VADOFT, in order to predict pesticide transport and transformation down through the crop root and unsaturated zone. A detailed list of changes is available in the release notes.

May 30, 2006

  • CEAM has updated the MINTEQA2 model for use on Windows 2000 and XP computer systems. The MINTEQA2 model and its associated PRODEFA2 software were recompiled and released as version 4.03. Model functionality remains unchanged, however, the system is now compatible with a wider range of Windows operating systems. A detailed list of changes is available in the release notes.
  • A new component database containing Monomethylmercury (MMHg) and Tributyltin (TBT) is also distributed with MINTEQA2 version 4.03. The addition of this new database and accompanying documentation will permit researchers to simulate the aqueous chemical speciation of MMHg and TBT.

April 17, 2006

  • Two models developed by the EPA Center for Public Health and Environmental Assessment (CPHEA) are now available through CEAM.
  • The Interspecies Correlation Estimations (ICE) for Acute Toxicity to Aquatic Organisms and Wildlife program was developed to allow prediction of acute toxicity to taxa with limited toxicity databases such as endangered species.
  • The Acute-to-Chronic Estimation (ACE) with Time-Concentration-Effect Models program was developed to allow prediction of chronic toxicity from acute toxicity datasets.

January 10, 2006

  • Hurricane Katrina Modeling Demonstration - EPA and Battelle have a CRADA agreement to attempt to link near-field models, such as the Visual Plumes UM3 model, with large-scale hydrodynamic models, such as Battelle's implementation of the Finite Volume Coastal Ocean Model (FVCOM). This download is a preliminary demonstration of FVCOM applied to flood waters generated by Hurricane Katrina and discharged to Lake Pontchartrain.

Additions and updates on the Exposure Assessment Models Web site prior to 2006 are available.