OSWER Models Study: Promoting Appropriate Use of Models in Hazardous Waste / Superfund Programs PHASE I FINAL REPORT May 26,1989 Information Management Staff Office of Program Management and Technology Office of Solid Waste and Emergency Response ------- OSWER Models Study: Promoting Appropriate Use of Models in Hazardous Waste / Superfund Programs PHASE I FINAL REPORT May 26,1989 Information Management Staff Office of Program Management and Technology Office of Solid Waste and Emergency Response ------- ACKNOWLEDGEMENT The OSWER Information Management Staff (IMS) wishes to thank all those who have contributed to this effort, especially members of the Hazardous Waste / Superfund Research Committee, OSWER's Technology Staff, the Office of Solid Waste, the Office of Emergency and Remedial Response, the Office of Air Quality Planning and Standards, EPA Regions ffl and V, Office of Research and Development (ORD) Headquarters offices and ORD laboratories in Athens, GA, Ada, OK, Cincinnati, OH, and Research Triangle Park, NC. American Management Systems, Inc. (AMS) assisted OSWER IMS in preparing this report. AMS collected information, conducted interviews with study participants, and provided analytical support throughout the study. AMS services were provided under Contract No. 68-01-7281. ------- OSWER Models Study-- Promoting Appropriate Use of Models In Hazardous Waste / Suoerfund Programs Table of Contents Page Executive Summary i 1. Background and Methodology : 1-1 1.1. Purpose 1-2 1.2. Project Plan 1-3 1.3. Project Activities 1-4 2. Overview of the Modeling Environment 2-1 2.1. Scope and Size 2-1 2.2 Key Research Organizations and Modeling Centers 2-3 2.3. Computing Environment 2-5 2.4. Model Development, Verification, and Validation 2-6 2.5. Model Selection and Application 2-8 2.6. Levels of Usage 2-9 2.7. User Support 2-10 3. Modeling Environment Category Descriptions 3-1 3.1. Ground Water Modeling 3-2 3.2. Exposure Assessment Modeling 3-12 3.3. Air Dispersion Modeling 3-17 3.4. Modeling for Hazardous Waste Engineering 3-23 3.5. Surface Water Modeling 3-25 3.6. Drinking Water Modeling 3-28 ------- Table of Contents (cont'd) Page 4. Review of Management Issues 4-1 4.1. Importance of Modeling 4-2 4.2. Need for Guidance 4-4 4.3. Model Development, Calibration, Verification, and Validation 4-6 4.4. Hardware and Software 4-8 4.5. Model Selection and Application 4-9 4.6. User Support Organizations and Networks 4-10 5. Recommendations 5.1. Task Area 1: Initiation, Additional Studies, and Preparation of Management Plan 5-1 5.2. Task Area 2: Development of Guidance 5-4 5.3. Task Area 3: Establishment of User Support Networks 5-6 Appendix A: Interview Guide A-l Appendix B: Interview List. B-l Appendix C: Bibliography C-l Appendix D: OSWER Models Inventory - Abbreviated D-l ------- Executive Summary During the 1970s and 1980s, there has been a steady increase in the frequency with which computerized, mathematical models are used at EPA by program office staff as tools for supporting regulatory decision-making. Models offer valuable new capabilities and significantly increase predictive power under conditions of incomplete information or uncertainty. On the other hand, as model development and usage proliferates, senior managers and technical staff are concerned about the difficulty in ensuring that models will be applied in appropriate and valid ways. Many models now run on Agency-standard personal computers and are readily available to non-experts with no formal training in model development or application. At EPA, these concerns are underscored by recent cases in which the application of a model has been challenged in court (e.g., McLouth Steel Products Corp. v. Thomas. 1987). Many of the model management issues affecting the Agency as a whole are particularly relevant to the programs managed by the Office of Solid Waste and Emergency Response (OSWER) and mandated by the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response Compensation and Liability Act (CERCLA). The Information Management Staff in OSWER's Office of Program Management and Technology (OPMT) has conducted this Models Study in order to develop a better understanding of the scope and size of the modeling environment of hazardous waste / Superfund (HW/SF) programs, to identify associated management issues, and to prepare a set of recommendations for promoting the appropriate use of models. The scope of the study is on computer- based mathematical models used to predict or simulate environmental effects. Physical models are not included in the study, and there is limited emphasis on management and economic (i.e., "cost") models. The purpose of this report is to describe the OSWER modeling environment, to identify management issues, and to make recommendations for future improvement initiatives. The Information Management Staff coordinated this project with the members of the HW/SF Research Subcommittees. Those members have provided sources of information and comments on the draft findings, issues, and recommendations. The project team collected its baseline information through in-person and telephone interviews at EPA Headquarters, Regional Offices, and several Office of Research and Development (ORD) research facilities. During these information gathering activities, the project team ------- compiled the OSWER Models Library, a collection of over seventy reference documents, and the OSWER Models Inventory, a computerized database containing descriptive information on over 300 models. The OSWER modeling environment is comprised of several heterogeneous modeling categories focusing on different environmental media, processes, and pathways. The six categories are: Ground Water, Exposure Assessment, Air Dispersion, Surface Water, Hazardous Waste Engineering, and Drinking Water. The following observations are presented in this report: • Scope and Size. There are more than 310 models of interest to hazardous waste / Superfund programs. • Key Research Organizations and Modeling Centers. The primary organizations involved in development are the EPA Office of Research and Development (especially through research laboratories in Ada, Athens, Cincinnati, and Research Triangle Park), EPA program offices (e.g., OSW, OERR, OPMT, OAQPS), universities and affiliated academic institutions (e.g., International Ground Water Modeling Center), and private scientific and engineering firms. • Computing Environment. The majority of existing models are written in FORTRAN. Older models run primarily on mainframes or minicomputers, but many have been adapted to run on microcomputers. Newer models are primarily targeted for delivery on microcomputers or workstations, using a variety of languages and tools. • Development, Verification, Validation. Currently, efforts for model development are evenly distributed between equation development, software development, model modification, and the combination of existing models. This is in contrast to the past, when the major emphasis in modeling was on equation development and programming. Model verification and validation are topics of much discussion and some controversy in the modeling community. There are no universally accepted definitions of model verification and validation. • Model Selection and Application. Model selection requires expert knowledge of both the process to be modeled and the models available. Model application is the process of using a particular model to make predictions and conduct analyses. Depending on how well the model fits the scenario, validation steps are often repeated as part of die model application process. As a model becomes widely distributed and applied in different scenarios, it becomes difficult to keep track of its performance under different circumstances. If ------- • Levels of Usage. This study has not been able to determine the exact frequency of model usage. There are no tracking systems to monitor actual usage in the field, but the facts to support the claim that model usage is widespread and growing steadily include: (1) thousands of copies of models are being requested yearly, (2) the availability of microcomputers and microcomputer based models, (3) the scope and emphasis of OSWER programs. Ground water, exposure assessment, and engineering models appear to be the types most commonly used for OSWER programs • User Support. The need for user support has been recognized by the modeling community, but a fundamental lack of human resources limits the quality of support services. Mechanisms such as technology transfer activities, training seminars, electronic bulletin boards, user groups, and clearinghouses for documentation are available to most modelers, but flexible, application-specific support and consultation with a modeling expert are needed in many instances. Based on the information gathered in describing the OSWER modeling environment and following discussions at several meetings with members of the Hazardous Waste / Superfund Research Subcommittees from OSWER and ORD, the project team identified and analyzed six major management issues: • Issue #1: What is the relative importance of models in supporting hazardous waste / Superfund program activities? • Issue #2: Is formal guidance on modeling necessary? If so, how should the guidance be developed and by whom? • Issue #3: How should OSWER and ORD manage model development, calibration, verification, and validation? • Issue #4: What types of standards should be imposed on hardware and software? • Issue #5: How should model selection and application be occurring in the field? • Issue #6: What types of user support organization and products should be created for model users? The analysis of these issues and discussions with OSWER and ORD members of the Hazardous Waste / Superfund Research Subcommittee generated a series of alternative action items. The project team developed a recommended action plan that organizes '" the various action items into a manageable sequence and ------- recognizes the importance of obtaining endorsement from top management in OSWER and ORD in order to carry out a multi- year, interdisciplinary improvement effort. Three major task areas are proposed: • Task Area 1: Initiation/ Additional Study/ and Preparation of Management Plan. This task area includes briefings for OSWER and ORD senior management on results of the Models Study/ development of a detailed management plan for modeling improvements/ conducting additional studies of the legal and policy issues related to modeling/ and gathering more in-depth information on model usage in the Regional offices. The overall purpose of the tasks is to educate senior managers and obtain top-level endorsement for future plans/ including commitment of resources/ and clarification of roles and responsibilities. • Task Area 2: Development of Guidance for Modeling. This task area covers the development of the various types of guidance necessary for modeling in Hazardous Waste / Superfund Programs. Three guidance products are specified: (a) guidance on model development/ validation/ and verification/ focused on the concerns of model developers and addressing peer review and the relationship between validation and Data Quality Objectives (DQO); (b) reviews of the current and future computing approaches for models/ including periodic 'Technology Updates" and suggestions for maintaining and distributing modeling software; (c) guidance on selection and application of models/ focused on model users in the Regional offices. • Task Area 3: Establishment of User Support Network for HW/SF Modeling. Several new user support mechanisms and/or organizational relationships are called for. Regional Modeling Groups (RMGs) are envisioned as a service bureau in each Region/ providing a central pool of modeling expertise. RMG staff will have a portion of their time dedicated to fulfilling their RMG roles and will communicate directly with the ORD Modeling Centers and the OSWER Modeling Support Group. The ORD Modeling Centers will be the primary source of scientific and technical support for Regional model users. They will have a media orientation, reflecting the strengths of different labs in different media/ and they will develop models, modify codes, add enhancements, conduct . training courses, consult with users about specific modeling applications, and pro-actively monitor the field performance of the models they are supporting. The OSWER Modeling Support' Group will have a dual mission: first, it will be primarily responsible for managing the development and dissemination of guidance materials on modeling; second, it will provide RMGs and other users with specific policy and jv legal advice on model applications. This includes reporting ------- on significant policy and legal events that affect the future use of models (e.g., court cases, new regulations). The anticipated timeline for the action plan covers the latter half of FY '89 through FY '92. Preliminary resource estimates include a minimum of 15 FTEs and at least $300K of extramural funds. Both the timeline and the resource requirements will be specified in greater detail in the OSWER-ORD Models Management Plan which will be developed under Task Area 1 of the Action Plan. ------- Section 1. Background and Methodology Senior EPA managers and Agency support groups such as the Science Advisory Board (SAB) have recognized the increasing frequency with which program office staff are using computerized, mathematical models to predict environmental effects and make regulatory decisions. Several major factors are contributing to this trend, including: • It is either technically infeasible or too costly to gather complete data for some of EPA's newer, broad-ranging programs, and the use of models helps to support decision- making under conditions of incomplete information or uncertainty. • A larger proportion of environmental scientists and engineers receive training in mathematical forrmilation and solution techniques and are actively seeking ways to apply these methods to EPA's regulatory programs. • Developments in computer technology have increased the number of tools available to the modeler, made it easier to develop models, significantly increased their speed, and added to output options (e.g., graphics, maps). In particular, the wider availability and lower cost of microcomputers has eliminated many of the barriers between modelers and programmers and between programmers and end users. Computing technologies such as artificial intelligence and supercomputers have emerged from research labs and are now being used to solve modeling problems. • Scientific research on environmental processes during the past several decades has steadily advanced modelers' knowledge of physical and chemical processes and their ability to predict the transport and fate of many pollutants. As the number of models increases and users become a more diverse group, with widely varying levels of knowledge and experience, it becomes increasingly difficult to ensure that models are used appropriately. At EPA, these concerns are underscored by cases in which the application of a model has been challenged in court. An example is the 1988 court decision in McLouth Steel Products Corp. v. Thomas. No. 87-1049, that EPA failed to provide sufficient public notice and opportunity for comment on its plan to use the VHS model (Vertical Horizontal Spread model, EPA 1985) to grant or deny a de-listing petition under the RCRA program. 1-1 ------- SAB's Environmental Engineering Committee has recently produced a "Resolution on the Use of Mathematical Models for Regulatory Assessment and Decision-Making." It identifies critical issues that must be addressed in order to improve the use of models throughout EPA. Included in the resolution are calls for creating a central modeling coordination group to provide guidance in model selection and validation; ensuring that EPA hires and supports larger numbers of engineers and scientists with appropriate model development and application skills; ensuring that a systematic model management process is in place to respond to the introduction of new computer technologies and modeling approaches; and establishing proper peer review procedures at various levels. Section 1.1. Purpose In the Office of Solid Waste and Emergency Response (OSWER), the programs mandated by RCRA and CERCLA present unique opportunities to use models to improve regulatory decision-making. Under RCRA, for example, engineering models can help assess the costs and benefits of alternative containment approaches at Treatment, Storage, and Disposal facilities (TSDs). At Superfund sites, models can be used to predict transport and fate of pollutants in multiple media — ground water, air, surface water, and drinking water. For these types of analyses, decision makers can rely on models to provide predictive information and improve their understanding of the environmental processes under consideration. However, even though RCRA and CERCLA programs present many opportunities for using models, there are no standards or guidelines on when and where specific models should be used. The Office of Air Quality Planning and Standards (OAQPS) is an example of a program office that has developed guidelines for applying models to specific types of regulatory decisions. One modeling challenge for OSWER is to ensure that models are being applied appropriately and consistently, while recognizing that there may be hundreds of different scenarios and site-specific issues affecting model usage under RCRA and CERCLA. In addition, OSWER must address other modeling challenges, such as providing adequate technical support, delivering sufficiently powerful computers to model users, and training program office staff. The Information Management Staff in OSWER's Office of Program Management and Technology initiated this models study in October, 1988, in order to develop a better understanding 1-2 of the scope and size of the modeling environment for hazardous ------- waste / Superfund (HW/SF) programs, and to identify associated management issues. Project kick-off meetings were held with OSWER and ORD members of the Hazardous Waste / Superfund Research Committee. One of the products of these meeting was the development of the following project charter: For the purposes of this modeling study, the following definition for the term model, as set forth b\j the American Society for Testing and Materials (ASTM, 1984) in a protocol for evaluating environmental chemical-fate models, will apply: A model is an assembly of concepts in the form of a mathematical equation that portrays understanding of a natural phenomenon. This study is concerned with models that are used by the Office of Solid Waste and Emergency Response to support programmatic decisions and compliance and enforcement actions. In particular, the focus is on models that use computer software to perform numerical computations and prepare estimates based on physical laws, probabilities, and statistics; the results of these models help predict environmental or scientific effects. The scope of the study may extend to economic and management models (e.g., cost recovery, workload estimation), but these are not the highest priority. Physical models will not be addressed by the study. The purpose of this report is to describe the OSWER modeling environment, review various management issues associated with modeling in HW/SF programs, and present a recommended action plan for promoting appropriate model use. Section 1.2. Project Plan The project plan for the Models Study included three major tasks: • Task 1 — conducting interviews, reviewing reference materials, and conducting analysis to accurately and concisely describe the current modeling environment for hazardous waste / Superfund programs; • Task 2 — incorporating feedback received on the modeling environment description and working with ORD and OSWER managers to identify and prioritize management issues associated with model development, usage, and support; 1-3 ------- Task 3 - preparing a final report and action plan specifying future activities designed to further promote the efficient and effective use of models to support OSWER program activities. Section 1.3. Project Activities Two kick-off meetings were held at the end of October, 1988, to initiate the project. The first was attended by ORD subcommittee members of the Hazardous Waste / Superfund Research Committee and project team members from the OSWER Information Management Staff and American Management Systems, Inc.,. The second meeting was attended by OSWER subcommittee members of the Committee and the project team. The scope and priorities for the modeling study were key issues at both meetings. Participants stressed the need to clarify terms and establish basic definitions. As a follow-up activity, the project team prepared the project charter presented above in Section 1,2. Following the kick-off meetings, the project team collected comments from the OSWER and ORD subcommittee members and gathered information on important points of contact identified during the meetings. A flexible Interview Guide (see Appendix A) was prepared in order to ensure consistency for the interviews but allow the project team to explore special topics in-depth with the interviewee as appropriate. Beginning in November, 1988, and through February 27,1989, the project team conducted forty-nine in-person and three telephone interviews at EPA Headquarters, Regional Offices, and several ORD research facilities, located in the cities shown in Exhibit 1.3-1. Appendix B lists the names, dates, and locations of the interviews. During the interviewing sessions and through other information gathering activities, the project team has also compiled the OSWER Models Library, a collection of over seventy reference documents such as model user's guides, modeling studies, and research papers. Appendix C contains the current bibliography for the OSWER Models Library. Another product developed for this project is the OSWER Models Inventory, a database of descriptive information on over 300 models of interest for HW/SF programs. Appendix D confirms expects for the OSWER Models Inventory. At the conclusion of the information gathering phase in March, 1989, the project team issued a draft report entitled "Description of the Hazardous Waste / Superfund Modeling Environment." That report described the OSWER modeling environment, providing information on past and present modeling activities and identifying over 300 models of interest to ------- HW/SF programs. The information presented in that report has now been updated to incorporate comments received from document reviewers. Much of the content of that report is reprinted Sections 2 and 3 of this document. Philadelphia, PA Washington, D.C. Indianapolis, IN • Cincinnati, OH • Exhibit 1.3-1. Interview Locations On April 4th, the project team met with members of the HW/SF Research Subcommittees from OSWER and the Office of Research and Development (ORD). The purpose of this meeting was to review the draft report cited above and to begin identifying management issues for modeling. The project team prepared a Review of Management Issues which discusses six major issue areas in a logical sequence. For each of the issue areas, this section provides a re-cap of key findings related to the issues, presents a preliminary conclusion/resolution for the issue, and identifies several alternative action items. This review is now contained in Section 4 of this document. Following the April 4th meeting, the project team met again with members of the ORD and OSWER HW/SF Research Subcommittees on April 25th to discuss the management issues identified earlier and prepare the recommendations now contained in Section 5 of this document. The section on Recommendations organizes the various issues and related action items into a concise action plan for achieving the desired improvements for models management and usage. It also outlines a suggested sequence of events and describes responsibilities and specific products. 1-5 ------- Sections 4 and 5 are based primarily on the discussions that took place at the April 4th and 25th meetings, and the project team's subsequent analysis of those issues. Other sources of input include individual meetings with key OSWER and ORD managers and information gathered at a meeting of the Science Advisory Board held on April 6th-7th to discuss Agency-wide modeling issues. 1-6 ------- Section 2. Overview of the Modeling Environment Section 2.1 This section provides a high-level, comparative overview of the HW/SF modeling environment. In keeping with the purpose of this report, the information presented here and in Section 3 is descriptive, not evaluative; it is the basis for the review of management issues and recommendations presented in Sections 4 and 5. The modeling environment includes several heterogeneous modeling categories focusing on different environmental media, processes, and pathways. The major categories comprising the modeling environment are: • Ground Water Modeling • Exposure Assessment Modeling • Air Dispersion Modeling • Surface Water Modeling • Modeling for Hazardous Waste Engineering • Drinking Water Modeling. The organization of modeling activities into these six categories generally mirrors the way modeling activities are organized within ORD and the way information was presented to the project team. However, these categories are not mutually exclusive, and there are numerous models that are relevant to multiple categories (e.g., exposure assessment models focused on surface water pathways). For a more detailed description of the categories, see the individual, category-by-category sub-sections in Section 3. Scope and Size 2-1 This study has so far identified 311 models of interest to hazardous waste / Superfund programs. This is a conservative estimate, subject to several qualifiers. First, the estimate includes only models that fit the definitions and focus for this project — i.e., computerized mathematical models used to make predictions based on physical laws, probabilities, and statistics. Desk-top ------- procedures are not included. Second, the estimate includes mostly EPA related models identified through the interviews (see Appendix B for a list of names and dates) and reviews of reference documents listed in the Bibliography (Appendix C). A comprehensive survey of academic institutions, government agencies, and industrial organizations was not conducted. Finally, because no tracking systems exist to monitor actual usage and model validation experiences in the field, models included in this total are only those cited by the interviewees as having been used in hazardous waste / Superfund programs or those whose functional description matches with one or more OSWER program requirements. The total universe of all possible models could be two or three times the initial estimate, depending on the definitions and criteria used. Among the universe of available models, a comparatively small subset appears to be used intensively by OSWER program staff at EPA Headquarters and in the Regions. For instance, of the twenty eight air dispersion models identified, one model in particular, the Industrial Source Complex (ISC) model, is used much more frequently than other air models because its orientation and assumptions are more compatible with RCRA and CERCLA program requirements. As show in Exhibit 2.1-1, the largest single category of models is ground water models, numbering over 240 and accounting for nearly eighty percent of the total model inventory. None of the other model categories contains more than 30 models. In terms of scope, models exhibit a wide range of variability across several dimensions: • Temporal scales vary from minutes and seconds to decades and even millennia (e.g., for some ground water models). • Spatial scales vary from molecular sizes (e.g., for models of chemical reactions) to hundreds of miles (e.g., for air dispersion models). • Numerical methods vary from simple analytical solutions to complex, multidimensional numerical simulations. • Models predict outcomes for events ranging from chemical interactions to biological processes to physical movement of particles and liquids through various media. Models also address engineering problems (e.g., for landfills, incinerators). • Models can be used to support decision-making for a wide range of programmatic activities — from permitting to compliance checking to enforcement to remediation. 2-2 ------- Hazardous Waste Drinking Engineering Water Exposure Air Dispersion, Emissions 27 Surface Water 21 Exhibit 2.1-1. Number of models in each category Section 2.2. Key Research Organizations and Modeling Centers ORD laboratories are the lead EPA organizations for research and model development. Individual laboratories focus on specific categories of models — for example, the Robert S. Kerr Environmental Research Laboratory (RSKERL) is the lead lab for ground water research and modeling, and the Environmental Research Laboratory at Athens (ERL-Athens) is the focal point for surface water models and a variety of exposure assessment models. Some of the labs have established specialized modeling support centers. RSKERL works closely with the International Ground Water Modeling Center, which is part of the Holcomb Research Institute at Butler University in Indianapolis, Indiana. ERL- Athens has created the Center for Exposure Assessment Modeling (CEAM). CEAM is a matrix organization that has established relationships with researchers, modelers, and technical support staff at Athens and other parts of ORD. Several of the labs are involved in more than one type of modeling. Exhibit 2.2-1 shows ------- the various relationships between model categories and ORD labs. The specific types of modeling activities conducted by these labs is described in more detail in Section 3. c Modeling Categories Ground Water Modeling ORD Labs and Affiliates I Exposure Assessment Modeling c c c c Air Dispersion Modeling Modeling for Hazardous Waste Engineering Surface Water Modeling Drinking Water Modeling Robert S. Kerf ERL, Ada, and Holcomb Research Institute ERL-Athens and the Center for Exposure Assessment Modeling Air Research and Exposure Assessment Laboratory, RTF Risk Reduction Engineering Laboratory, Cincinnati Environmental Monitoring and Systems Lab, Las Vegas Air and Energy Engineering Laboratory, RTF Exhibit 22-1 In addition to the ORD laboratories, there are a variety of other organizations that directly or indirectly support modelers and model users. These include: • The OSWER Office of Program Management and Technology (OPMT). One of OPMT's main modeling activities has been in the area of ground water modeling, where it procured and deployed the Ground Water Workstation in each of the ten Regions. The workstation provides a pre-packaged set of four models and a limited set of other automated tools. OPMT has established a network of Technology Support Centers for Remedial Project Managers (RPMs) and On-Scene Coordinators (OSCs). This effort includes the creation of the Ground Water Forum, Engineering Forum, and Exposure Assessment Forum, designed to provide Superfund staff with a convenient way to identify appropriate media or technology experts. • The Office of Solid Waste (OSW). OSW has been involved in modeling to varying degrees over the past several years. OSW currently maintains a modeling oversight role and sponsors some model development efforts within ORD. In addition, 2-4 ------- OSW is supporting an internal effort to develop a ground water model called the EPA Composite Landfill Model. The Center for Environmental Research Information (CERI). CERI is an ORD organization based in Cincinnati, Ohio, that supports technology transfer throughout the Agency by producing and distributing technical reports and sponsoring various types of seminars and training courses. CERI is not involved in model development directly, but can serve as a distributor of models or documentation on models. CERI has agreed to provide this type of support for expert systems being developed by the ORD. CERI also assists with the testing of expert systems in various stages of development. The Office of Toxic Substances (OTS). OTS has supported the development of GEMS, the Graphical Exposure Modeling System. GEMS has been used by OSW for hazardous waste incinerator regulations, unsaturated zone modeling, and estimation of physical-chemical properties for waste constituents. Section 2.3. Computing Environment The computing environment consists of the hardware, software, and peripheral equipment used to develop and run models. As a group, modelers have no established forum for discussing new product offerings and alternative computing approaches, but there are common characteristics and trends in computing for the various model categories. The following observations about computing environments are applicable to all modeling categories, unless noted otherwise: • The increasing availability and power of microcomputers has had a major impact on model development and usage. Most modelers now use microcomputers for development and target micros as their delivery platform. • DOS-compatible micros with math co-processors are now the modeler's most common hardware unit. Other hardware includes Apple Macintoshes, Hewlett Packard microcomputers, SUN workstations, VAX minicomputers, and IBM mainframes. • No official software standard exists for models, but because of its popularity and acceptance, FORTRAN has become a de facto standard for some model developers. There is a high level of interest in standardizing FORTRAN styles and selecting a 2.5 common version that will ensure portability across platforms ------- (i.e., ANSI FORTRAN 77). This "standard" has been promoted for hydrologic models by the U.S. Geological in a report entitled "FORTRAN 77 Coding Conventions and Documentation Software" (USGS Open File Report, Kittle, Runbe, and Flyn, 1986). • A variety of other programming languages are used as well, including C, Pascal, and Basic. Some models draw upon the capabilities of software packages for managing data and improving input and output features. Packages include dBASE, HyperCard, Lotus 1-2-3, and expert system shells. • Supercomputer technology is not an immediate priority given the current set of research initiatives and model development priorities. There are a few exceptions to this, for example in the air programs, where issues such as acid rain and global warming may necessitate the development of a new class of large-scale computer models. Even though modelers rely on the same basic hardware and software tools for computing, they employ different model development approaches and place different degrees of emphasis on software engineering issues. User interfaces and model output capabilities vary significantly from model to model. Models provide widely varying levels of on-line help, ease of entry for input values, and elegance of reports. User interface issues are resolved differently, depending on the sophistication of the model and the orientation of the modeler. Some modelers have an "anti- menu" philosophy and assume the user will be a proficient programmer with in-depth understanding of the internal workings of the model. In some cases, users must almost always consult with the modeler on how to run the model. These types of models typically run in batch mode on a mainframe while the inputs are entered through an editor or through programming statements. At the other end of the spectrum, there are model interfaces which assume the user is a non-expert. These models may have interactive front-ends with on-line help. Non-programmers can easily enter and edit input values. A few recently developed models have incorporated window-based, icon-oriented front-ends. Section 2.4. Model Development, Verification, and Validation The term "model development" refers to: (1) initial development of equations; (2) programming of computer code; (3) modification of existing model codes to handle new types of calculations and simulations; and (4) linking of previously 2-6 incompatible models. A significant amount of model ------- development activity falls into the last two categories. The impetus for model development comes as a response to events such as: • Outgrowths from primary research into some new area of environmental science, hydrology, or other discipline (e.g., as dissertation topics or EPA funded R&D projects) • Requirements for analyzing contamination problems at a particular site or group of sites with a certain set of distinguishing characteristics (e.g., in response to requests from EPA Headquarters or Regional offices) • Needs for developing decision support tools in order to implement programs, created by new legislation or sets of regulations (e.g., Clean Air Act, RCRA, CERCLA). The primary organizations involved in development of the models identified in this study are the EPA Office of Research and Development (primarily through its research, laboratories in Ada, Athens, Cincinnati, and Research Triangle Park), EPA program offices (e.g., OSW, OERR, OPMT, OAQPS), universities and affiliated academic institutions (e.g., the International Ground Water Modeling Center (IGWMQ), and private scientific and engineering firms. A significant amount of introspective analysis in the modeling community has been devoted to addressing model development, selection, verification, validation, and application issues. Two recent reports touching on these issues are "Groundwater Modeling: An Overview and Status Report" and "Selection, Application, and Validation of Environmental Models" (for references, see the Bibliography in Appendix C). The Agency's Exposure Assessment Group (EAG) has produced some suggested definitions and guidance on model validation. Ongoing efforts include work by a Technical Panel of the Risk Assessment Forum to develop an Agency position on model validation in predictive exposure assessments. Despite these efforts, no hard and fast rules yet exist to govern model development and validation processes. The consensus among modelers is that this may not be desirable anyway, as there are generally understood "rules of the road" and principles of "good science." Moreover, the model development and validation process is strongly influenced by institutional factors such as who is sponsoring the effort, what type of standards are imposed by the sponsor, and the intended use of the model. For example, a researcher developing a model in art academic setting (e.g., as a dissertation) may be subject to different peer review requirements than a modeler working in an ORD laboratory. Controversy has sometimes surrounded the definition of _ _ terms such as "verification" and "validation." The general ------- consensus is that verification and validation address two separate questions: (1) For verification, "Are the numerical equations of the model properly captured in the computer code?" and (2) For validation, "Not is the model absolutely valid, but is it being applied in a valid manner?" As implied by these questions, verification is more limited to development of model codes, whereas validation takes place both as part of the development effort and as part of the application process. Modelers typically conduct some type of validation as part of their development effort, but this is often limited by a lack of resource availability. The validation of a model using "real" field data can take years of effort. For example, the exposure assessment model PRZM underwent five years of validation efforts (at considerable cost) to determine the valid boundaries for the application of the model. Section 2.5. Model Selection and Application To select a model, an analyst must have information about the particular site or scenario being studied, plus a thorough understanding of the strengths and weaknesses of available models. A framework for model selection in the Superfund program was developed in 1985 (see "Modeling Remedial Actions at Uncontrolled Hazardous Waste Sites" in the Bibliography, Appendix C). This framework is sufficiently general mat it could be used by OSW with some minor modifications. Responsibilities for model selection vary from case to case, but an EPA project officer at Headquarters or in a Regional office will be the final decision-maker. In some cases, contractors make recommendations on appropriate models for a particular analysis. EPA staff concur or disagree with these recommendations based on their own experience or technical advice supplied by ORD modeling experts. (ORD has developed a prototype expert system which can help a modeler select the correct model). Model application is the process of using a particular model to make predictions and conduct analyses. Depending on how well the model fits the scenario, validation steps are often repeated as part of the model application process. As a model becomes widely distributed and applied in different scenarios, it becomes difficult to keep track of its validity under multiple stresses. Site-specific . models must be both calibrated and validated every time they are used at a new site. Modelers and managers stress that there is no foreseeable way to eliminate the possibility that models will be misused, but there are ways to reduce the likelihood of this happening. Ensuring that 2-8 model users have the necessary knowledge and experience to ------- properly apply the model and understand the limitations of its predictive power is one crucial requirement for meeting this challenge. In the Superfund program, the Regional Project Managers (RPMs) rely on contractors to utilize models for various parts of the Remedial Investigation / Feasibility Study (RI/FS) process. RPMs do not need to be modelers, but they must have a clear understanding of how to apply models appropriately and know when an in-depth review of a modeling exercise is warranted. Section 2.6. Levels of Usage This study has not been able to determine the exact frequency of model usage. There are no tracking systems to monitor actual usage in the field, but several facts support the claim that model usage is widespread and growing steadily: • During FY '88, CEAM distributed over over 1,500 copies of the dozen models it manages; over 1,900 copies were distributed in FY '87. • The increasing availability of microcomputers in the field and the trend toward micro-based models has significantly reduced entry barriers. OSWER's Ground Water Workstation provides a readily accessible modeling tool for all ten Regional offices. • The scope of OSWER programs and the growing emphasis on exposure- and risk-based decision-making make modeling the only feasible course of action in many cases. Monitoring can be too costly and take too long. Even though model usage as a whole may be on the rise, the usage of models by personnel in the Regional offices tends to be restricted by a lack of time, computer availability, training, and other resource issues. Actual usage levels vary significantly from Region to Region and across media. Ground water, exposure assessment, and engineering models are the types most commonly used for OSWER programs. Although modeling growth is difficult to quantify, exposure modeling is probably the most rapidly expanding category. 2-9 ------- Section 2.7. User Support Numerous mechanisms are in place to support model users, including: • Technology transfer activities (e.g., the OSWER Technology Support Project for RPMs and OSCs, which includes the establishment of groups such as the Ground Water Forum and Engineering Forum) • Periodic training seminars and short courses (e.g., ground water modeling courses sponsored by the Ada lab, short courses taught by IGWMC) • Electronic bulletin boards (e.g., the OSWER bulletin board at Headquarters, the CEAM bulletin board in Athens, and the UNAMAP bulletin board in RTF) • Clearinghouses for documentation (e.g., the CERI, CEAM, and IGWMC). Despite the availability of this type of support, there is a limited amount of coordination among the different activities. Users often have difficulty determining where to go first for various types of support. The most pressing user support needs can be directly linked to human resource issues. In conjunction with the installation of the Ground Water Workstation, some Regions have established dedicated modeling support groups, but other Regions have no staff members devoted to modeling and very few staff with modeling experience. Most Regional RCRA and CERCLA program staff have heavy demands on their time (e.g., some RPMs manage thirty or more sites simultaneously) and have no time to devote to developing additional modeling expertise. Often, because of their busy schedules, those who could benefit most from additional training on modeling are the least likely to attend training when it is offered. Managers in the Regions are sometimes reluctant to allow their staff to attend modeling courses because it takes valuable time away from day-to-day priorities. 2-10 ------- Section 3. Modeling Environment Category Descriptions This section provides individual descriptions for the six modeling categories identified in this study: • Ground Water Modeling • Exposure Assessment Modeling • Air Dispersion Modeling • Surface Water Modeling • Modeling for Hazardous Waste Engineering • Drinking Water Modeling. These descriptions offer an in-depth look at the types of modeling and support activities being conducted by the various EPA Headquarters, ORD research laboratories, and Regional offices. Each description covers the size and scope of the modeling category, the relationship of these types of models to OSWER programs, the key organizations and modeling centers, and individual findings on model development, usage, and support. The organization of modeling activities into these six categories generally mirrors the way modeling activities are organized within ORD and the way information was presented to the project team. In order to minimize confusion and avoid double counting, models are assigned to only one of the categories, although there are cases where a particular model could be included in multiple categories. The Exposure Assessment and Engineering categories, in particular, represent modeling disciplines and cut across media such as surface water, drinking water, and air. Later phases of this project will address the need to develop more precise categories. The documents referenced by footnotes in this section can be found in the Bibliography in Appendix C. The convention used for footnotes is (Xn), where X is a one-letter code for the model category and n is a sequence number. 3-1 ------- Section 3.1. Ground Water Modeling Size and Scope Ground water modeling is the largest single category of models used to support OSWER program activities. Estimates vary depending on how they are grouped and defined, but conservatively, there are over 250 ground water models that are related to OSWER requirements or have been used by OSWER program staff. Ground water modeling is also one of the most dynamic categories in terms of development of new model codes and the increasing number of cases in which models are being used to support programmatic decisions. A major reason for the size of this category is the of the medium itself. As Exhibit 3.1-1 shows, ground water models simulate many different relationships between ground water and other elements of the hydrosphere. •vaporatloi U DW A ER f Zft N /Q UJ F 3-2 Exhibit 3.1-1 (reprinted from G10) Added to this set of relationships are the numerous temporal and spatial scales which the models address. Spatial scales range from less than a nanometer to hundreds of kilometers. Temporal scales cover both steady-state and time-dependent conditions and can range from minutes and seconds in real-time systems to ------- hourly, daily, weekly, or monthly for field systems, to years, decades, and millennia for long-term risk simulations (e.g., for radioactive wastes). Another dimension of the ground water modeling field is the difference in characteristics between models describing hydraulic behavior of fluids in various subsurface environments and models describing the transport and fate of chemicals in the subsurface. Finally, there is a distinction between site-specific and generic models. Site-specific modeling is particularly relevant to hazardous waste sites falling under the purview of RCRA and CERCLA. Generic models are useful in situations where environmental analysis must be applied to many sites where data availability is limited or other constraints make site-specific modeling infeasible. Relationship to OSWER Programs Environmental legislation and regulations, including RCRA and CERCLA, address four common requirements for managing ground water quality: • Establishment of criteria for location, design, and operation of waste disposal activities to prevent contamination of ground water or movement of contaminants to points of withdrawal or discharge. • Assessment of the probable impact of existing pollution on ground water at points of withdrawal or discharge. • Development of remediation technologies which are effective in protecting or restoring ground water quality without being unnecessarily complex or costly, and without unduly restricting other land use activities. • Regulation of the production, use, and/or disposal of specific chemicals possessing an unacceptably high potential for contaminating ground water when released to the subsurface (G21). Ground water models may address one or more of these requirements in a variety of different applications. For example, the predictive capabilities of ground water quality models are used to evaluate design alternatives for waste disposal facilities, locate areas of potential environmental risk, identify pollution sources, and assess possible remedial actions. 3-3 ------- Key Ground Water Research Organizations and Modeling Centers Robert S. Kerr Environmental Research Laboratory Holcomb Research Institute There are several key EPA and affiliated organizations involved in ground water modeling. Because ground water modeling is a broad, multidisciplinary field, this section focuses on OSWER-related ground water modeling activities. For example, the U.S. Geological Survey has been involved in ground water modeling since the late 1960s and has developed a comprehensive suite of generic simulation and parameter estimation models. The Robert S. Kerr Environmental Research Laboratory (RSKERL) in Ada, Oklahoma, is the lead ORD laboratory for ground water research. RSKERL focuses on the transport and fate of contaminants in the subsurface, development of methodologies for protection and restoration of ground water quality, and evaluation of the applicability and limitations of using natural soil and subsurface processes for the treatment of hazardous wastes. RSKERL carries out research through in-house projects and cooperative and inter-agency agreements with universities, national laboratories, and other research centers. Many of these projects involve some type of research and development activity related to the creation or refinement of ground water models. The Holcomb Research Institute (HRI) at Butler University in Indianapolis, Indiana, established The International Ground Water Modeling Center (IGWMC) in 1978 to advance and support the application of ground water models by regulatory and oversight agencies involved in developing effective ground water management programs. IGWMC is supported partly by HRI and partly by EPA (through RSKERL in Ada). The Center operates a clearinghouse for ground water modeling software, organizes and conducts short-courses and seminars, carries out a research program supporting its technology transfer and educational activities, and does verification and validation for some models. IGWMC also maintains close ties with ground water modelers at USGS and has established an agreement to provide similar types of support to the European Economic Community. In the future, IGWMC will include European ground water models into its existing model inventory and clearinghouse function. 3-4 ------- Athens Environmental Research Laboratory OSWER'sOfficeof Program Management and Technology Office of Solid Waste Findings The Athens Environmental Research Laboratory (A-ERL) collaborates with RSKERL in several ground water research and model development efforts. In particular, A-ERL supports PRZM and MINTEQ, both of which are used in ground water analysis, the former for root zone soil/water exposure and the latter for geochemical analysis. Later this year, A-ERL will begin supporting RUSTIC, an integrated soil/ground water model. The Office of Program Management and Technology (OPMT) provides management and technical support for Headquarters and Regional Offices. OPMT's primary involvement in ground water modeling is through the deployment and support of the Ground Water Workstation (GWWS) in each of the ten regions. GWWS is a microcomputer (PC-AT) equipped with a math co-processor, plotter, and light pen. Four models were supplied with the initial release of the GWWS, and OPMT is now evaluating requirements for the next generation of GWWS. OPMT has also helped to establish a Ground Water Forum through its Technology Support Project. The purpose of the Forum is to provide a channel for communication on ground water issues, including modeling. The Forum has one or more representatives from each Region and two ORD representatives (from RSKERL and the Environmental Monitoring and Systems Laboratory in Las Vegas). The Office of Solid Waste (OSW) has been involved in ground water modeling to varying degrees in the past. Currently, the Technical Assessment Branch in OSW's Characterization and Assessment Division is developing a ground water model called the EPA Composite Landfill Model (EPACLM). At one time, OSW had a larger in-house modeling group, but now, OSW maintains more of an oversight role, supporting the development of models by ORD and supporting users of ground water models in the Regional offices. The findings presented below have been synthesized from numerous interviews conducted at EPA Headquarters, RSKERL, Regional Offices, and HRI (see Appendix B for names and dates) and through the review of a variety of ground water modeling reference materials (see Appendix C). 3-5 ------- Ground water modeling has matured rapidly since numerical methods were first used in ground water hydrology in the mid- Mode/ Developmen t 1950s. In the 1960s, the availability of computer technology made it possible to simulate ground water systems efficiently through the use of software instead of physical scale models or electric analogs (G10). Today, IGWMC has identified approximately 800 ground water models which are in various stages of development and usage. Models are being developed by a variety of government agencies, such as EPA and USGS, universities, and industrial organizations, such as energy and mining companies. One example of the work being done within EPA is at RSKERL, where recent model research and development efforts include: • The Regulatory and Investigative Treatment Zone Model (RITZ). • OASIS • Contaminated Profile (CONTPRO). Some model development efforts begin in an academic setting as research projects. These tend to be more focused on modeling new processes or improving predictive power in ground water systems. Other efforts are initiated as the direct result of requests from program offices such as Regional Waste Management Divisions. Such was the case for CONTPRO, which was originated after a request from EPA Region nt. (CONTPRO is currently being developed at Oklahoma State University and is written in Microsoft C). Typically, before RSKERL staff get involved in a modeling effort, requests for assistance are directed from the Regional offices to their Ground Water Forum Representative and then to the lab managers. New modeling initiatives typically follow in the wake of advances in primary research. RSKERL is actively participating and/or sponsoring ground water research in several new areas, such as flows of multi-phase fluids, fractured/structured rock problems, biotransformations in ground water, and the mobility of large molecules through the soil. The increasing availability of microcomputers has had a significant impact on model development. In ground water modeling, there is a general consensus that microcomputers and workstations are the preferred platforms for development and delivery. Most ground water researchers are now targeting micros as their delivery environment and there is a greater proportion of modelers who develop their own code. At RSKERL, for example, there are numerous IBM compatible microcomputers and one Apple Macintosh, and the ratio of staff to micros is close to 1:1. RSKERL plans to continue to upgrade its computing capacity in the 3*6 ------- future, and is now considering the purchase of several more Macintoshes. Currently, there are few models requiring significant increases in computing capacity that would necessitate the use of supercomputer technology, although in the future this technology might be extremely valuable in answering long-term risk questions for large areas and populations (e.g., predicting the long-term effects of ground water contamination in a large aquifer on human health in a metropolitan area). Modelers report that data entry and user interface issues are still a major obstacle affecting usability. They note the importance of good software engineering practices in producing quality front- end capabilities such as data entry screens in contributing to the acceptance of a model by users. RTTZ is a PC-based model that provides a good example of a simple and effective user interface consisting of three data entry screens. OASIS is an example of an effort designed to incorporate an icon-oriented user interface as a front-end for ground water models: it is based on the Macintosh and uses HyperCard software to provide users with simple point- and-click commands. OASIS then passes the user inputs to a model, which in this case, is a FORTRAN model called BIOPLUME. The ground water modeling community has devoted a great deal of attention to analyzing development, application, verification, and validation issues. IGWMC has taken the lead in many of these efforts to describe and recommend standard model development and application procedures (see documents in the Bibliography under "Ground Water", Appendix C). These studies and interviews with ground water modelers can be summarized as follows: • There are generally understood "rules of the road" and principles of "good science," but there are no universally accepted standards for model development, application, and use. • Managers and modelers do not always agree on definitions for key terms such as "verification" and "validation." For EPA purposes, the way around this controversy is to focus on answering two questions: (1) For verification, "Are the numerical equations of the model properly captured in the computer code?" and (2) For validation, the key question is whether the model is being applied appropriately, given the model's assumptions and the characteristics of the specific modeling case. • There is no foreseeable way to entirely eliminate the possibility that models will be misused, but there are ways to reduce the likelihood of this happening. Some modeling experts feel that the best way to do this is to focus on improving the knowledge 3-7 ------- Model Ueveiopmen t Ground water modeling has matured rapidly since numerical methods were first used in ground water hydrology in the mid- 1950s. In the 1960s, the availability of computer technology made it possible to simulate ground water systems efficiently through the use of software instead of physical scale models or electric analogs (G10). Today, IGWMC has identified approximately 800 ground water models which are in various stages of development and usage. Models are being developed by a variety of government agencies, such as EPA and USGS, universities, and industrial organizations, such as energy and mining companies. One example of the work being done within EPA is at RSKERL, where recent model research and development efforts include: • The Regulatory and Investigative Treatment Zone Model (RITZ). • OASIS • Contaminated Profile (CONTPRO). Some model development efforts begin in an academic setting as research projects. These tend to be more focused on modeling new processes or improving predictive power in ground water systems. Other efforts are initiated as the direct result of requests from program offices such as Regional Waste Management Divisions. Such was the case for CONTPRO, which was originated after a request from EPA Region ffl. (CONTPRO is currently being developed at Oklahoma State University and is written in Microsoft C). Typically, before RSKERL staff get involved in a modeling effort, requests for assistance are directed from the Regional offices to their Ground Water Forum Representative and then to the lab managers. New modeling initiatives typically follow in the wake of advances in primary research. RSKERL is actively participating and/or sponsoring ground water research in several new areas, such as flows of multi-phase fluids, fractured/structured rock problems, biotransformations in ground water, and the mobility of large molecules through the soil. The increasing availability of microcomputers has had a significant impact on model development. In ground water modeling, there is a general consensus that microcomputers and workstations are the preferred platforms for development and delivery. Most ground water researchers are now targeting micros as their delivery environment and there is a greater proportion of modelers who develop their own code. At RSKERL, for example, there are numerous IBM compatible microcomputers and one Apple Macintosh, and the ratio of staff to micros is dose to 1:1. RSKERL plans to continue to upgrade its computing capacity in the 3*6 ------- future, and is now considering the purchase of several more Macintoshes. Currently, there are few models requiring significant increases in computing capacity that would necessitate the use of supercomputer technology, although in the future this technology might be extremely valuable in answering long-term risk questions for large areas and populations (e.g., predicting the long-term effects of ground water contamination in a large aquifer on human health in a metropolitan area). Modelers report that data entry and user interface issues are still a major obstacle affecting usability. They note the importance of good software engineering practices in producing quality front- end capabilities such as data entry screens in contributing to the acceptance of a model by users. RTTZ is a PC-based model that provides a good example of a simple and effective user interface consisting of three data entry screens. OASIS is an example of an effort designed to incorporate an icon-oriented user interface as a front-end for ground water models: it is based on the Macintosh and uses HyperCard software to provide users with simple point- and-click commands. OASIS then passes the user inputs to a model, which in this case, is a FORTRAN model called BIOPLUME. The ground water modeling community has devoted a great deal of attention to analyzing development, application, verification, and validation issues. IGWMC has taken the lead in many of these efforts to describe and recommend standard model development and application procedures (sese documents in the Bibliography under "Ground Water", Appendix C). These studies and interviews with ground water modelers can be summarized as follows: • There are generally understood "rules of the road" and principles of "good science," but there are no universally accepted standards for model development, application, and use. • Managers and modelers do not always agree on definitions for key terms such as "verification" and "validation." For EPA purposes, the way around this controversy is to focus on answering two questions: (1) For verification, "Are the numerical equations of the model properly captured in the computer code?" and (2) For validation, the key question is whether the model is being applied appropriately, given the model's assumptions and the characteristics of the specific modeling case. • There is no foreseeable way to entirely eliminate the possibility that models will be misused, but there are ways to reduce the likelihood of this happening. Some modeling experts feel that the best way to do this is to focus on improving the knowledge 3-7 ------- and experience of the model users, not to worry about flawless software. • Model validation is a continual process. Modelers are typically involved in some type of validation effort for their model, but as the model becomes more widely distributed and applied in different scenarios, it becomes difficult to keep track of its successes and failures. Model clearinghouses and user support groups can make a major contribution in this area. • Peer review processes for models are mostly determined by the organization sponsoring the development. For example, peer review procedures within EPA are often different from those followed by universities. • Some modelers suggest that high level attempts to establish a standard set of approved models may have the undesirable effect of limiting innovation. • Model selection is a complex issue that involves clearly answering such difficult questions as: "What is the specific question that must be answered?" and "What level of uncertainty is acceptable?". • Often there is a trade-off between selecting a model that best fits the ground water conditions and one that best fits the regulatory scenario. Usage and Support The organizations identified earlier all directly or indirectly support ground water modeling in the field: RSKERL, IGWMC, OPMT, and the Ground Water Forum. RSKERL and IGWMC are the main sources providing guidance on model selection, application and validation. They also conduct training through "short courses" and Regional seminars. OPMT supports the Ground Water Workstation program which has deployed a microcomputer equipped with a basic modeling tool kit in each of the ten Regions. OPMT has also sponsored training on the workstation and provided documentation. The Ground Water Forum provides a central forum for the discussion of ground water issues, including modeling. IGWMC is the primary user support organization for ground water modeling, maintaining a database of approximately 800 models, including documentation for approximately 300 models. IGWMC manages and distributes codes for 50-60 models. IGWMC has also provided testing and validation services to model users. In the future, IGWMC would like to expand its offerings to include an electronic bulletin board and maintain a more complete set of QA information for each model (e.g., track records of model performance under various scenarios). Some models may have many different versions and changes are often managed on an ad _ _ hoc basis. 3*8 ------- IGWMC also provides testing and validation services to model users. At the high end, IGWMC works directly with the model users and/or developers to discuss technical issues and address requirements for refinement and validation. At the low end, IGWMC may provide users with some limited documentation and advise them to "use at your own discretion." For IGWMC, it is becoming increasingly challenging to effectively support non-expert users as ground water models become more complex and incorporate new issues (e.g., microbiology). Therefore, developing and maintaining forums for user and modeler communication, such as user groups and bulletin boards, will be of greater importance in the future. Regional office staff devote a significant portion of their efforts to reviews of contractors' proposals, work plans, and remediation efforts. Many contractors submit models and their results to the EPA for review. The Regional office must determine if the proper model has been chosen for the site, and whether or not the model has been applied in a valid manner. Therefore, the EPA reviewer needs to understand the available models and their valid application, and be able to identify cases where an in-depth review of a contractor's work is warranted. In some contested cases, EPA reviewers may need to compare their own modeling results with modeling results of regulated facilities, Principal Responsible Parties (PRPs), and their consultants. Alternative model assumptions, parameters, and boundary conditions must be considered carefully in order to validate the model application. In the Regional offices, the use of ground water models is limited by constraints on time, human resources, and computer resources. The following user support issues were identified by the Regions: • To be used effectively by staff in the Regional Waste Management Divisions, models must be easy to learn and significantly improve either the quality of decision-making or the efficiency with which decisions can be made. • The expertise and knowledge to use models cannot be acquired quickly in most cases. In most cases, the users are not modeling experts. They may have training in hydrology, geology, toxicology, management, or environmental science, but typically, they will not have in-depth modeling experience. Models are just one of several tools they rely on to perform their jobs. • Limited availability of computer resources and lack of computer skills increase the costs of using models both in terms of time and money. Some models require users to procure additional software packages or hardware (e.g., math _ _ co-processors), and many models assume the user has a 3*9 ------- certain amount of computer expertise in order to input data and run the model. These requirements and assumptions create entry barriers for unprepared and uninitiated model users. In addition to these user support issues, Regional model users identified a variety of entry barriers for modeling. These include: • Data input is too time consuming. • Data is not always available. • The model does not make use of all the information available. • The model makes too many assumptions. • The model is too complex to understand. • Debugging input files takes too much time. Regional model users are satisfied with some of the types of user support available to them. Some have contacts in ORD laboratories or academia, whom they call on for assistance. Some user groups and training classes are viewed as helpful, but only if the modelers can return from the classes and immediately apply what they have learned. Some formal training in ground water modeling has been attempted on a national scale. During the summer of 1988, for example, RSKERL completed a series of three-day seminars in each of the ten EPA Regions. These seminars provided attendees with descriptions for a selected subset of models, explained model assumptions and variability, and included some hands-on training. Source code was distributed for some of the models. The seminars were attended by a combination of Superfund and RCRA staff from the Regions, as well as contractor staff The coordinator of these seminars provided the following observations: • Model usage varies significantly from Region to Region, and depends on the level of expertise in the Regional or EPA-HQ program offices, the availability of an appropriate model with sufficient documentation, and the complexity of the problem to be analyzed. • Some Regions have in-house hydrologists and geologists who are experienced modelers. Other Regions have practically no staff with any in-depth modeling experience. • On average, Regional staff involved in RCRA and CERCLA programs face heavy demands on their time (e.g., some RPMs manage more than twenty sites simultaneously) and have no time to devote to acquiring additional modeling expertise. 3-10 ------- • Often, because of their busy schedules, those who could benefit most from additional training are the least likely to attend training when it is offered. Regional staff often skip modeling courses because of more pressing day-to-day activities. • Basic computer literacy is sometimes a significant obstacle to making the training sessions worthwhile. RSKERL and IGWMC agree that more technical expertise is needed in all Regions. Regional staff do not need to be modelers, but they need to be knowledgeable generalists who can make decisions after reviewing information from a variety of sources (e.g., ORD, PRPs, contractors). The Regions also need computer support staff who can eliminate some of the confusion created by difficult user interfaces and complex sets of operating instructions for some models. RSKERL plans to continue sponsoring seminars and training on ground water models and is now assessing priorities and formats for future courses. 3-11 ------- Section 3.2. Exposure Assessment Modeling Size and Scope Relationship to OSWER Programs Exposure assessment modeling is a growing category of models useful for supporting OSWER program activities. This study has so far identified more than a dozen readily available models, not including the many under development by various universities and research organizations. The number and variety of available exposure assessment models has increased steadily in recent years because they have proven to be valuable components of risk-based decision processes. This trend is likely to continue in the 1990s. The majority of exposure assessment models identified so far focuses on ecological exposure where water is the primary pathway. They represent a wide range of analysis techniques, including simple analytical procedures suitable for screening analysis, computerized steady-state models, state-of-the-art continuous simulation models, and interactive graphics. Exposure assessment models relating to human exposure also exist for air and other pathways. Exposure assessment modeling is usually directly related to transport and fate modeling in various media, and therefore, coordination and cross-fertilization among the various research organizations with in-depth expertise in these media is necessary. Exposure assessment models have been used under various legislative mandates, including RCRA, and CERCLA. Exposure assessment models can be used by Regional RCRA and Superfund staff and their consultants to make decisions on issues such as human and ecological exposures resulting from contamination at Superfund sites and emissions resulting from hazardous waste incinerators. Examples of the types of capabilities available to OSWER through the exposure assessment models identified so far include: • multimedia modeling of organic chemical and heavy metal pollutant fate • regional and local air contaminant modeling • source and site characterization, monitoring, and measurement 3-12 marine and estuarine pollutant fate modeling ------- Key Exposure Assessment Research Organizations and Modeling Centers pollutant dose-response modeling ecological impact and ecological risk assessment. (El) Center for Exposure Assessment Modeling This section briefly describes the major exposure assessment modeling centers and research organizations identified in this study. Exposure assessment can be applied to most environmental media, and organizations other than those listed here may also be engaged in exposure assessment modeling. An example of an organization which has not been categorized here under exposure assessment is the Atmospheric Research and Exposure Assessment Laboratory (AREAL) which was created recently to increase the emphasis on developing exposure assessment models for air. AREAL is categorized under Air Dispersion Modeling in this report because it is not yet heavily involved in exposure modeling and most of its prior modeling activities are related to air dispersion analyses. The Center for Exposure Assessment Modeling (CEAM) was established in July, 1987 to meet the scientific and technical exposure assessment needs of EPA program offices at both the Headquarters and Regional levels, as well as state environmental agencies. CEAM is the OSWER-designated Technical Support Center for Ecological Risk Assessment. The Center is also the focal point for a variety of general Agency support activities related to the scientifically defensible application of state-of-the-art exposure assessment technology for environmental risk-based decisions. CEAM provides exposure assessment technology, training and consultation for analysts and decision-makers operating under various legislative mandates, including RCRA, and CERCLA. CEAM is a matrix organization within ORD which draws its exposure assessment expertise from its parent laboratory, the Environmental Research Laboratory at Athens, Georgia (ERL- Athens), plus affiliated laboratories including ERL-Duluth; the Environmental Monitoring Systems Laboratory, Las Vegas, NV (EMSL-Las Vegas); ERL-Narragansett; the Atmospheric Research and Exposure Assessment Laboratory (AREAL), Research Triangle Park (formerly, the Atmospheric Sciences Research Laboratory and the Environmental Monitoring Systems Laboratory at RTP); ERL- Gulf Breeze;; and EMSL-Cincinnati. CEAM currently supports twelve exposure assessment models, six of which are related to remedial actions. Other models are currently being integrated into the CEAM program. 3-13 ------- Office of Toxic Substances Atmospheric Research and Exposure Assessment Laboratory Findings Model Developmen t The Office of Toxic Substances (OTS) has supported the development of GEMS, the Graphical Exposure Modeling System. GEMS has been used by OSW for hazardous waste incinerator regulations, unsaturated zone modeling, and estimation of physical-chemical properties for waste constituents. AREAL focuses on exposure assessments for air pathways and is currently working on basic assumptions about units of exposure. One existing model is called the Simulation of Human Activity Patterns (SHAPE). SHAPE predicts carbon monoxide exposure for humans under various activity scenarios. Field tests and data collection for this model are now being conducted in Denver, Colorado, and Washington, D.C. The findings presented below have been synthesized from numerous interviews conducted at EPA Headquarters and several ORD laboratories (see Appendix B for names and dates) and through the review of a variety of exposure assessment modeling reference materials (see Appendix C). In the exposure assessment category, recent model development efforts have concentrated on the integration and combination of existing models, rather than on the development of entirely new models. New models are also being developed, but a greater emphasis has been placed on conjunctive use of various types of models addressing different exposure pathways and/or environmental processes. For example, one research project under way at ERL-Athens involves piecing together several models, essentially using the outputs of one model as the inputs for the next. This is a complex task which attempts to make estimates based on estimates. One thrust of this project is to isolate and identify the basic levels of complexity which can be handled within acceptable bounds of uncertainty. Another thrust of the investigation is to develop consistent interfaces between models. Other model development projects focusing on ecological risk assessment, land disposal of hazardous wastes, and exposure assessment models for pesticides include: • Multimedia Exposure Assessment Model for Hazardous Wastes • Pesticide Ground Water Exposure Assessment Model • Terrestrial Environmental Exposure Assessment Model. Another ERL-Athens research effort is focused on validating certain model assumptions for Eco-Risk models such as FGETS. For GEMS, recent development work has produced a PC-based user interface which can be readily distributed and used. 3-14 ------- CEAM has established several basic development standards for models distributed by the Center. These include hardware, software, portability, and documentation guidelines and criteria which must be met before the Center will accept a model for support and distribution. The CEAM software standard is ANSI FORTRAN 77; all models are compiled successfully using four different FORTRAN compilers before they are approved for distribution. This procedure assures portability between a variety of hardware platforms including mainframes (IBM, PRIME, Cyber, HP), minicomputers (VAX), and microcomputers (IBM PC/AT). Comprehensive scientific and user documentation is also required for acceptance. CEAM also plays a significant role in the verification, validation, and quality control of exposure assessment models. For verification, CEAM undertakes a detailed code-level review of models. This assures internal consistency and valid representation of scientific equations. CEAM has worked with the EPA Office of Water to develop waste load allocation guidance documents, which address some model application and validation issues, but do not provide specific guidelines. CEAM participates in validating exposure assessment models primarily through two activities: peer review journals and user group meetings. The issue of model validation is itself a research topic at CEAM. For example, the exposure model PRZM underwent five years of validation efforts (at considerable cost) to determine the valid boundaries for the application of the model. Model Usage and Although CEAM functions influence the development of Support exposure assessment models, the primary purpose of the Center is to provide expert support services for the users of CEAM models. CEAM provides services in three primary functional areas: • Model Distribution and Maintenance. This functions ensures that those conducting exposure assessments have access to the necessary models, databases, and analytical techniques. This involves model acquisition, preparation, maintenance, distribution, support, and quality assurance. CEAM distributes and supports a set of twelve exposure assessment models; three to four models will be added to this set during the next year. Distribution includes model codes as well as documentation and reference materials. CEAM distributed over 1,500 copies of models last year and over 1,900 copies in FY '87. One tool used to support the distribution and support function is an electronic bulletin board. The bulletin board enables callers to download model codes and some types of documents, as well as leave messages and ask questions about particular models. About one-third of the models distributed last year were sent out electronically via the bulletin board. The remaining two-thirds of the models were distributed in user-requested formats on floppy disks or tapes. 3.15 Four full-time CEAM staff members, including contractors, ------- are dedicated to the technical provision function. This function also covers the maintenance of a user database, model recalls, issuance of updated codes, and software reviews to ensure uniform coding styles and constructs. CEAM conducts line-by-line code reviews for some of the models it distributes. The Center does not function as a clearinghouse for all exposure assessment models. As research and development lead to new or improved modeling capabilities, CEAM updates presently supported models and adopts new models. • Technical Support. CEAM offers extensive technical support for all of the models distributed by the Center. Support includes training and seminars, phone support, input data analysis and error correction through the bulletin board, site- specific guidance, and access to subject matter experts. CEAM emphasizes support because some type of technical assistance is required for most model applications. Phone support is provided mainly through contractor staff. CEAM staff provides direct consulting support for those models they thoroughly understand; they provide contact with outside experts for other models. Training consists of three- to five- day short courses in the use and application of certain CEAM models. CEAM presented two short courses in FY88: "Models of Exposure and Bioaccumulation of Organic Toxicants in Surface Waters," held in Washington, DC, and Boulder, Colorado, and the "Metals Equilibrium Speciation Model (MINTEQA2)," held in Boulder, Colorado. Three short courses are planned for FY89. CEAM provides site-specific guidance in cases where the exposure assessment modeling expertise of the CEAM staff is needed. An example of this is the support requested by OSW at a wood preservative waste site in Georgia. CEAM staff members used PRZM and FGETS, two CEAM models, to assist with the analysis of the waste site. CEAM staff may assist with model selection and application when requested. • Demonstration. The purpose of technical demonstration is to specifically demonstrate the models and techniques supported by the Center. Through these demonstrations, CEAM can promote new analysis techniques and address specific management issues. One technical demonstration currently underway is an eco-risk analysis in the Clark Fork River, Montana. The analysis team was drawn from the staffs of ERL Athens and ERL Duluth. CEAM currently supports only twelve models because of the interest in providing solid technical support for each of the available models. Therefore, models are added to CEAM inventory at a gradual rate which ensures they can be effectively supported with existing resources. 3-16 ------- Section 3.3 Air Dispersion Modeling Size and Scope Relationship to OSWER Programs 3-17 Air dispersion models have been managed and used over a longer period of time than most other model types. The core set of EPA air dispersion models, called the Users Network for Applied Modeling of Air Pollution (UNAMAP), has existed since 1973. UNAMAP consists of 23 air dispersion models of various types which have been funded and/or developed by EPA. Historically, air dispersion models have been used primarily to support development of State Implementation Plans (SIPs) mandated by the Clean Air Act, and to conduct new source reviews. Because of the difficulty and high cost of collecting air monitoring data with comprehensive spatial and temporal coverage, models have been widely used in many air quality ^assessments, supported by actual air data where possible. The use . of models is authorized by Federal regulations (40 CFR, Parts 51 and 52) issued under the authority of the Clean Air Act. These regulations specify the EPA Guideline on Air Quality Models as the official guidance document for determining which UNAMAP models are best suited to a particular regulatory requirement. Criteria influencing the selection of the preferred models include: short-term (1-24 hours) vs. long-term (monthly, seasonal, or annual); type of source (single, multiple, complicated, buoyant); type of terrain (simple or complex); and land use (urban, rural). Many of the widely used air dispersion models pre-date RCRA and CERCLA and are oriented toward air regulatory programs managed by the Office of Air Quality Planning and Standards (OAQPS). In recent years, however, there has been increasing interest in using air models to support OSW and OERR programs. For OSW, one of the main areas of interest is in modeling air dispersion patterns in order to predict the transport of pollutants emitted from hazardous waste incinerators. For OERR's purposes, air dispersion models can be valuable in assessing volatilization of pollutants from Superfund sites. Exhibit 3.3-1 shows some of the air contaminant pathways from a landfill. Models can sometimes be the only feasible way to determine safe courses of action, such as evacuation in emergency cases where there are sudden releases of hazardous materials into the air. Air modelers in ORD have identified some of the air models that are most directly applicable to OSWER programs. These include a model that can be used at landfill sites containing hazardous wastes and a model that simulates instantaneous releases of hazardous materials and could be used in an emergency response situation. ------- DIRECT AIR EMSSKMS OF VOLAT1LES * PARTCULATE MATTER QA8VENTMQ FROM VENTS VOLATILIZATION OF UNSOLVED SPECIES M GROUND WATER LATERAL HKIRATION OFVOLATILES FROM SOLID WASTE LATERAL MIGRATION OFVOLATILES FROM CONTAMMATEO SCNLSALEACHATE Exhibit 33-1 (reprinted from A7) Key Air Dispersion Research Organizations and Modeling Centers Atmospheric Research and Exposure Assessment Laboratory 3-18 Three major air dispersion modeling centers and research organizations have been identified through the project team's interviews at EPA Headquarters, ORD laboratories, and selected EPA Regional Offices. The Atmospheric Research and Exposure Assessment Laboratory (AREAL), in Research Triangle Park, North Carolina, formerly the Atmospheric Science Research Laboratory (ASRL), and the Environmental Monitoring Systems Laboratory (EMSL) manage the UNAMAP set of models. Activities supporting UNAMAP include software maintenance and issuance of new model codes. AREAL is currently operating an electronic bulletin board. The bulletin board is used to distribute copies of models and a limited amount of documentation, and it provides a communication channel for UNAMAP users. AREAL is now assessing future plans for continued operation of the bulletin board. One option under consideration is transferring responsibility for the bulletin board to OAQPS (see below). AREAL's research and model development activities include application of existing models in new regulatory settings, development of a climatological Point, Area, and Line Source model (PAL), and research on indoor air pollution. AREAL also provides technical support for other offices and agencies such as the Office of Toxic Substances (OTS) and the Federal Emergency Management Agency (FEMA). ------- Air and Energy The Air and Energy Engineering Research Laboratory (AEERL) Engineering Research conducts research on preventing Hazardous Air Pollutant / Laboratory Volatile Organic Compound (HAP/VOC) emissions and ensuring effective application of control devices. This research supports the development of New Source Performance Standards (NSPS) and State Implementation Plans. AEERL also provides direct engineering technical support to EPA Regional Offices and state and local agencies. One of AEERL's ongoing research projects with direct relevance to OSW is the investigation of hazardous waste puffs from rotary kiln incinerators. This project involves the use of a small scale rotary kiln to measure the behavior of various materials under different combustion scenarios. Later phases of this project are likely to include some type of model development activity. Office of Air Quality The Office of Air Quality Planning and Standards (OAQPS) in Planning and Standards Research Triangle Park, North Carolina, is the program office responsible for developing the Guideline on Air Quality Models. During the 1970s and 1980s, OAQPS has worked directly with AREAL and AEERL (and formerly, with ASRL) on the development, review, and application of many of the UNAMAP models. OAQPS is now beginning work on updating the Guideline and has established a work group, with OSWER membership, to produce the revisions. OAQPS is also involved in the development of several air emissions models (in collaboration with the Risk Reduction and Engineering Laboratory in Cincinnati). OAQPS has relied in the past on AREAL and the National Technical Information Service (NTIS) to distribute the UNAMAP models. Current initiatives include the establishment of a new electronic bulletin board to replace AREAL's existing bulletin board. AREAL will continue to be involved in model development, application and validation and will continue to provide technical support for UNAMAP users. OAQPS will procure new hardware and establish a more formal user support group to operate the bulletin board. OAQPS has recently established a joint effort with OERR and the EPA Regions called the Air/Superfund Coordination Program. The purpose of this program is provide technical support in areas such as using air models to predict volatilization at Superfund sites. Findings The findings presented below have been synthesized from numerous interviews conducted at EPA Headquarters and 3 19 Regional offices, AREAL, AEERL, and OAQPS (see Appendix B for ------- names and dates) and through the review of a variety of air dispersion modeling guideline documents and reference materials (see Appendix C). Model Development The major research initiatives likely to add to the inventory of air models in the future are: • indoor air pollution • exposure assessments for air pathways • source apportionment for air toxics • studies of atmospheric transformations for ozone • regional and national acid rain studies. As for some of the other modeling categories, the trend in air modeling is increased emphasis on microcomputers and workstations for model development and delivery. Again, user interfaces are a key issue. Because of the need for large, complex regional air models to address issues such as acid rain and global warming, air has a more immediate need for supercomputer technology than some other areas. One of the unique aspects of the air modeling environment is the existence of OAQPS's Guideline on Air Quality Models which specifies preferred models for certain types of applications. The Guideline has the force of regulation since it is incorporated by reference in the Federal Register sections addressing Clean Air Act requirements. Two major factors led to the development of the Guideline: (1) the requirements set forth by the Clean Air Act that specified the use of models for developing air quality management plans; (2) the characteristics of the air medium make effective monitoring very difficult. OAQPS will be revising the Guideline in the future and has established a work group to produce the update. The work group will have three representatives from outside of the air program, including two OSWER representatives. 3-20 ------- The core group of models contained in UNAMAP changes periodically; the current version of UNAMAP is the sixth since its Model Usage and inception in the early 1970s. Presently, the UNAMAP models are a Support fairly stable set. UNAMAP is the main support mechanism for users of air dispersion models. There is a steady demand for the models and AREAL estimates that about half of all requests are for regulatory purposes (e.g., Prevention of Significant Deterioration (PSD) analysis). The National Technical Information Service (NTIS) distributes the complete series of UNAMAP models on magnetic tape at a cost of $1,285. The modeling codes available through NTIS are written primarily in ANSI FORTRAN 77. Some of the UNAMAP models are available in PC format, but this type of customization is usually left to the users or to private companies wishing to re-market the UNAMAP models. OAQPS has created compatible mainframe and PC versions for some models (e.g., ISC). A second option for obtaining the models is to use the AREAL electronic bulletin board. The bulletin board provides mostly source code, although AREAL intends to make more text files (e.g. documentation) available in the future. AREAL is assessing whether to continue its current use of the bulletin board, expand it, or transfer this responsibility to OAQPS. OAQPS has begun preparations for housing the bulletin board and plans to use a SUN workstation with four external ports as the host. OAQPS is also undertaking an initiative to improve the overall quality of documentation for UNAMAP models. AREAL issues periodic changes to UNAMAP through Versions and within Versions, through Changes. The current UNAMAP series is Version 6, Change 8. Mailing lists of all requestors are maintained and changes are sent out automatically. AREAL staff also provides consulting for users, although the staff stresses they are only providing information on the technical aspects of the models, not passing judgement on regulatory issues. During recent years, the user profile has changed to include a larger proportion of non-experts. One of the modeling support areas of relevance to OSWER is the Air/Superfund Coordination Program. This is a joint effort between OAQPS, OERR, and the Regions to evaluate and assist with the use of air models at Superfund sites;. The program is funded with Superfund resources, including contract money and Regional FTEs. Each Region has a designated Air/Superfund Coordinator who facilitates the air analysis portions of Superfund site investigations and remedial actions. At the Regional offices, air models are often needed to estimate the impacts of remediation efforts on air, including air stripping, incineration, and volatilization. Six of the twenty-three UNAMAP models have been identified as having applicability in RCRA and Superfund remediation sites. Of these six models, one ------- model, the Industrial Source Complex model (ISC), is the most commonly used. Other UNAMAP models are not widely applicable to Superfund and RCRA sites because of differences in the focus of the models, such as the orientation toward tall stack emissions versus wide area volatilization. Region HI is one of the most active Regions in the Air/Superfund Coordination Program, and has designated two modelers from the Air Management Division to provide support for Superfund analyses. These individuals spend approximately twenty-five percent of their time on Superfund related air analysis activities. Of this time, a little more than half is used for applying air models at specific Superfund sites. Air models were used by Region HI modelers at a total of twelve Superfund sites in 1988. Modeling activities include both reviewing the modeling efforts of contractors and hands-on modeling requested by the Remedial Project Manager. The modeling tools and techniques required for RCRA sites are similar to those of Superfund sites, but air models were used at only one or two RCRA sites in 1988. OAQPS's Guideline on Air Quality Models is not generally applicable to modeling in OSWER programs because of different regulatory requirements and different spatial scales. Currently, Superfund air modelers depend on their own expertise and past experiences with air models. OAQPS and the Regional offices are developing a document titled Procedures for Conducting Air Pathway Analyses for Superfund Activities, which addresses issues of consistency and quality in Superfund air analyses. This four volume document, currently in draft form, provides guidance on modeling and monitoring procedures to be used at Superfund sites. The document will also have relevance in RCRA air analyses. 3-22 ------- Section 3.4. Modeling for Hazardous Waste Engineering Size and Scope Relationship to OSWER Programs Hazardous Waste Engineering Research Organizations and Modeling Centers 3-23 The project team has identified four engineering models that are particularly relevant to Hazardous Waste Engineering / Superfund programs. The models are useful in the evaluation of earthen dike structures, hazardous waste incinerators, landfills, and liners. Although numerous other engineering models have been developed and may be in use by Regional offices, contractors, or industry, these four were of primary interest to the interviewees from OSWER and ORD: • Geotechnical Analysis for Review of Dike Stability (CARDS) - assists in the evaluation of existing and planned earth dike structures at hazardous waste facilities; • Energy-Mass Balance Model (EMBM) - simulates the performance of industrial incinerators for a variety of combustion scenarios; • Hydrologic Evaluation of Landfill Performance (HELP n) - models hydrologic effects at hazardous waste sites; • Soil Liner Model (SOILINER) - simulates the dynamics of infiltration through a compacted soil liner. More detailed information on these models is provided in the Models Inventory. Engineering models are used to support decisions meeting both RCRA and CERCLA requirements. For example, these types of models can be used to evaluate the design and configuration of Treatment, Storage, and Disposal Facilities (TSDs), as required by RCRA. Incinerators, soil liners, dikes, and other hazardous waste control technologies have been addressed by various types of engineering models. CERCLA applications for engineering models focus on containment approaches and remedial techniques such as incinerators for contaminated soils, impermeable barriers, and landfill caps. The Risk Reduction Engineering Laboratory (RREL) in Cincinnati, Ohio, which houses the former Hazardous Waste Engineering Research Laboratory (HWERL), is one of the key organizations involved in engineering models. RREL is responsible for the development and distribution of the four models mentioned above. ------- The Air and Energy Engineering Laboratory (AEERL) is also involved in engineering research. One of AEERL's current research projects is evaluating rotary kiln incineration of hazardous wastes. This effort will most likely result in the development of one or more models simulating various aspects of incineration. Other laboratories involved in engineering models include the Las Vegas Environmental Monitoring and Systems Laboratory (EMSL), and the Environmental Research Laboratory, Athens, Georgia (ERL Athens). Findings As compared to some other modeling categories, engineering models are a small group in terms of numbers. The models vary in terms of complexity according to the particular treatment technology they simulate. A few engineering models such as HELP n are widely distributed and account for the vast majority of total models distributed. FORTRAN is the primary language used for developing engineering models. Interviewees identified less than five ongoing ORD research projects that may lead to model development. Two examples are AEERL's research on rotary kiln incinerators mentioned above and an effort at RREL to develop a metals partitioning model mat predicts how metals behave under a variety of incineration scenarios. There are no formal user support and model distribution networks for engineering models. RREL typically provides copies of models on blank diskettes supplied by the requestor. RREL is considering establishing an arrangement with the Center for Environmental Research Information (CERI) to provide documentation and support. They have also considered providing this type of service through the National Technical Information Service (NTIS), but feel that CERI will be more economical and more responsive, (see the description of CERI in Section 2.3). RREL is also working with the Office of Solid Waste to investigate the use of expert systems technology for supporting the evaluation of "Method 90-90" data on flexible membrane liners. 3-24 ------- Section 3.5. Surface Water Modeling Size and Scope Surface water modeling covers a variety of processes which occur in the surface bodies of water. Modelers group these water bodies into three categories: rivers and streams, lakes and reservoirs, and estuaries and bays. Within these categories, lakes are sub-categorized into stratified or well mixed, and estuaries are sub-categorized into stratified, well mixed, or partly mixed. Of the three categories, estuaries and bays is the most complex because of the numerous forces acting on the waters, including tides, thermal mixing, and the Coriolis (spinning earth) effect. Because the transport of hazardous materials in surface water pathways is dependent on both the water and the underlying sediments, many surface water models simulate processes both in the water and in the sediments which underlie and intermingle with the water. Exhibit 3.5-1 diagrams the chemical and biological processes which occur in surface waters. VOLATILIZATION ATMOSPHERE MATER 01 X SEDINEK t DIRECT PHOTOLYSIS DISSOLVED POLLUTANT HYDROLYSIS-) OXIDATION FFUSION -1 TS ^ N BIODEGRADATION 1 ADSORPTION « DESORPTION BIOACCUHULATION '^Sp^ DISSOLVED BIOTA SENSITIZED PHOTOLYSIS P ARTICULATE HYDROLYSIS ADSORP DESORPTION * 1 L^«>4J DEPURATION 1 < 01 PARTKULATE POLLUTANT TION E-BI TEJ ' ^ACCUMULATION SEDIMENTATION -BIODEGRADATION * DAUGHTER PRODUCTS ALSO SUSCEPTABLE TO CHEMICAL PROCESSES 3-25 Exhibit 3.5-1 (reprinted from H7) This study has identified over thirty different surface water models representing a variety of water body categories, temporal scales, and dimensions. Other identifying characteristics of surface water models include the type of contamination source, such as ------- Relationship to OSWER Programs Key Surface Water Research Organizations and Modeling Centers Findings Model Developmen t non-point surface runoff or point sources, and the processes modeled, such as water flow, contaminant transport, or contaminant exposure. Surface water models can be valuable tools for performing analyses for both RCRA and Superfund programs. In cases involving illegal dumping or accidental discharges of hazardous wastes, there may be direct impacts on surface waters. Even for many land-based containment and remedial actions, analysts must often account for surface water runoff. For example, when applying for permits under RCRA, TSD facilities must show that surface water runoff from their sites will not pose any danger to humans or the environment. 3-26 There are a variety of ORD organizations involved in the development of surface water models and related research, including the Environmental Research Laboratories (ERLs) at Athens, Cincinnati, Narragansett, and Duluth, and the Environmental Monitoring and Systems Laboratory in Las Vegas. Historically, Athens-ERL has been the lead organization for developing and supporting surface water models and conducting related research. Athens-ERL's Center for Exposure Assessment Modeling (CEAM) supports five surface water toxicant models: WASP4, EXAMS H, HSPF9, SARAH,and DYNTOX It also supports QUAL2E, a conventional pollutant model, and DYNHYD4, a hydrodynamic model (see Section 3.2 for a more complete description of the types of services provided by Athens - ERL). CEAM evolved from the former Center for Water Quality Modeling, which was also housed at Athens. The findings presented below have been synthesized from the project team's interviews and the review of several reference documents on surface water modeling (see Appendices B and C). Surface water models are developed by a variety of organizations, including EPA and other Federal agencies such as NOAA and the Department of Agriculture, national research laboratories such as Oak Ridge, universities/ and private companies. No widely recognized guidelines exist for the development and validation of surface water models. The computing environments for the surface water models identified so far are similar to most other categories. Models have historically been developed in FORTRAN, primarily on IBM ------- mainframes. The current trend is a move towards microcomputer- based models which can be more widely used. Model Usage and Several guidelines partially addressing the selection and Support application of surface water models have been produced by EPA in recent years. These include Modeling Remedial Actions at Uncontrolled Hazardous Waste Sites and Selection Criteria for Mathematical Models Used in Exposure Assessments. Surface Water Models. These guidelines address the issues of proper model selection, application, and on-site validation. Also provided are case studies of example applications. Surface water models are not used extensively by OSWER program staff. They tend to be applied only in special cases. No clearinghouses, user support groups, bulletin boards, or training programs were identified as supporting surface water modelers. 3-27 ------- Section 3.6. Drinking Water Modeling Size and Scope Relationship to OSWER Programs Key Drinking Water Research Organisations and Modeling Centers One drinking water model relevant to OSWER programs, known as the Packed Column Air Stripping Model, has been included in the Models Inventory. This model has been used in determining the feasibility of air stripping for controlling moderately volatile synthetic organic chemicals (VOCs). It models the engineering process of air stripping VOCs from drinking water. Numerous other drinking water models oriented to engineering aspects of drinking water systems have been developed, but this model has the greatest potential for use by OSWER programs. Drinking water models relate to RCRA and CERCLA programs in two areas: engineering and risk assessments. For example, remedial actions at Superfund sites sometimes require the use of an air stripper for the treatment of water. Drinking water related engineering models can be used to estimate the amount of hazardous effluent which may be produced during a clean-up effort. Drinking water quality models may also be used in exposure and risk assessments of TSDs regulated under RCRA. There is no designated "lead" organization for drinking water models. The Technical Support Division of the Office of Drinking Water, Cincinnati, has been the key organization involved in applying the Packed Column Air Stripping Model. Other EPA organizations involved with drinking water research and model development include the Risk Reduction Engineering Laboratory, Cincinnati, the Environmental Monitoring Systems Laboratory, Las Vegas, the Robert S. Kerr Environmental Research Laboratory, Athens, and the Health Effects Research Laboratory, Research Triangle Park. 3-28 ------- Findings Other than the use of the Packed Column Air Stripping Model at certain Superfund cites, OSWER programs do not make heavy use of drinking water models. No forums for the distribution or support of drinking water models were identified. No specific examples of OSWER related applications of drinking water models were provided. 3-29 ------- Section 4. Review of Management Issues This section presents six major management issues in a logical sequence. These issues were identified through several meetings with members of the Hazardous Waste / Superfund Research Subcommittees from OSWER and ORD and through the project team's analysis of the information presented above in Sections 1, 2 and 3. The six management issues are: • Issue #1: What is the relative importance of models in supporting hazardous waste / Superfund program activities? • Issue #2: Is formal guidance on modeling necessary? If so, how should the guidance be developed and by whom? • Issue #3: How should OSWER and ORD manage model development, calibration, verification, and validation? • Issue #4: What types of standards should be imposed on hardware and software? • Issue #5: How should model selection and application be occurring in the field? • Issue #6: What types of user support organization and products should be created for model users? For each issue, key project findings are recounted, a preliminary conclusion is drawn, and alternative action items are suggested. The recommendations presented in Section 3 are based on the review of these issues. 4-1 ------- Issue #1: What is the relative importance of models In supporting hazardous waste / Superfund program activities? Key Findings: • Hundreds of computerized/ numerical models are available, for many different processes and environmental media. • In cases where collecting monitoring data is technically difficult and too costly to provide the sole basis for exposure assessment the use of models, either alone or in combination with monitoring results, provides for reasonably informed predictions about environmental processes. • The need for models is generally acknowledged by program managers, engineers, scientists, and the legal community. Some managers are generally supportive of modeling, allowing their staff to spend time using models and acquiring necessary expertise. Other managers feel that modeling takes too much time away from day-to-day activities such as writing permits and performing inspections. • Actual model usage levels are unknown, and there are no mechanisms in place to keep track of performance of particular models in the field. Preliminary Conclusion; In hazardous waste / Superfund programs (HW/SF), models are not the only tools for supporting program decisions, but models are sufficiently important decision-making tools that a coordinated management strategy for modeling is necessary. Inappropriate use of models results in wasted time and effort, ineffective enforcement and remediation, and in some cases, embarrassments for the Agency. The value of models and the importance of appropriate model use need to be articulated by all levels of EPA management. Managers, in turn, must provide their staff with dear direction on modeling and its relationship to other program activities. Related Action Items; • Increase awareness of senior managers (e.g., Assistant Administrators, Division Directors, Office Directors, Regional Administrators) about modeling issues, develop a management strategy, and obtain key endorsements supporting the use of models and emphasizing the ------- importance of applying models in a valid and consistent manner. Maintain dialogue with Science Advisory Board on their Agency-wide modeling resolution. Initiate discussions with other offices which may be helpful in managing /supporting modeling at an Agency level (e.g., ODRM/NDPD and the Agency-wide Technology Transfer Staff). 4-3 ------- Issue #2; Is forma/ guidance on modeling necessary? If so, how should the guidance be developed and by whom? Key Findings; • There are no mandatory or recommended models for OSWER programs. • Guidance on model selection and application is very limited; some is being developed for the use of air models at Superfund sites. • Some users oppose the establishment of strict model selection standards and lists of prescribed models. They claim flexibility is very important because of wide ranges of variation in site characteristics and regulatory scenarios. Preliminary Conclusion: Guidance on modeling in HW/SF programs is necessary. The guidance should be flexible, and it should be modular, addressing the needs and multiple perspectives of those who will be affected. Guidance on modeling should focus on core areas such as development of algorithms and computer code, but it should also recognize the importance of data collection and quality assurance in the modeling process. Guidance will be valuable in at least three areas: development, verification and validation (V&V) (primarily for modelers); hardware and software standards (primarily for modelers); and model selection and application (primarily for users). Related Action Items: • Convene a group of modeling experts from different disciplines and organizations to prepare guidance on model development and V&V. The guidance will be applicable to all models targeted for use in HW/SF programs, and should describe the model development, calibration, verification, and validation processes for all types of models, addressing differences among media where necessary. (See Issue #3 below.) • Consult with OIRM and information management groups in other program offices about the need to develop standards for hardware and software. Determine which types of standards 4-4 are desirable and feasible. (See Issue #4 below.) ------- Establish a group of RCRA and CERCLA program experts and selected modeling experts from each major modeling discipline to develop guidance on model selection and application. The guidance should include descriptions of recommended models for different media and different types of program decisions. (See Issue #5 below.) 4-5 ------- Issue #3: How should OSWER and ORD manage model development, calibration, verification, and validation? Key Findings: • Development procedures have been discussed extensively, but there is no universal agreement on "the right way" to develop models. There are no standard peer review procedures for models. • Most modelers agree on what verification is — in order for any model to be credible/ the developer must verify that the code performs its calculations and uses its equations as intended. • Validation is more subjective because there are only degrees of validity. It is rarely possible to do a complete validation effort - it takes too much time and costs too much. For some models, it is necessary to re-validate models with field data every time they are applied. Preliminary Conclusion: Previously, discussion of standard modeling procedures has occurred in a specific media context (e.g., ground water modeling, air modeling). Validation is one of the most controversial areas, but in this area as well as others, it should be possible to get modeling experts in different domains to reach consensus on a typical "life-cycle" for a model. The fundamental objective for guidance in the area of development, calibration, and V&V is to establish an agreed upon set of procedures for testing and review that will provide users with models of known quality and performance characteristics. Strengthened guidance in this area will minimize the likelihood that models used by EPA will be declared inaccurate or invalid in legal disputes with the regulated community. Related Action Items; • Develop guidance in this area focusing primarily on model developers (e.g, ORD labs, contractors). Such guidance should describe the model development process, or life-cycle, in general terms. Resolution of controversy on the issue of validation should be based upon the principles of Data Quality Objectives (DQO). 4-6 ------- Assess need to coordinate with other organizations involved in environmental modeling (e.g., NOAA, USGS, USDA, American Meteorological Society). Specify requirements for peer review for all models intended for use in OSWER programs. Obtain endorsement of this guidance by leading modelers in different fields and top level OSWER and ORD managers. 4-7 ------- fssue #4; What types of standards should bo imposed on hardware and software? Key Findings: • Modelers are actively applying new computing technologies in developing their models, including a variety of hardware platforms and software packages. • User interfaces, data input facilities, and programming styles vary widely from model to model. • Many models are developed outside of EPA, making it difficult to tightly control hardware and software. Preliminary Conclusion: Setting strict hardware and software standards will impose constraints on model developers and may be difficult to enforce (e.g., for third-party developers). Different types of standards may be appropriate for model developers vs. model users. Related Action Items; • Develop hardware and software standards, considering the need for different standards for model developers and end users. • Stipulate when standards apply (e.g., for cases where EPA is funding the development of a model for a particular "intended use") and link to guidance on model development. • Address need for ensuring that model distributors provide software of the highest possible quality - i.e., standard procedures for making updates, testing codes, and promoting similar programming styles and practices. 4-8 ------- Issue #5: How should model selection and application be occurring in the field? Key Findings; • Some users lack the technical background to know which models are optimal for certain types of analyses. • Staff do not always fully understand how their contractors or the regulated parties are using models; contractors are heavily involved in model selection and application. Preliminary Conclusion; There is a need for guidance on model selection and application that is both media-specific (e.g., groundwater, surface water, air) and program activity-specific (e.g., RCRA Corrective Action, Superfund RI/FS). In some cases, there may be no substitute for direct communication (e.g., via a hotline) between the user and the model expert. There is a need for a more precise way to categorize models. Related Action Items; • Conduct a study of how contractors are using models in HW/SF programs, and ensure that contractors are selecting models appropriately. • Assess various options for providing guidance on model selection and implement the most cost-effective solution. Identify proportions of cases where different types of guidance are most effective — e.g., written guidance vs. automated systems vs. direct consultation with experts. • As stated under Issue #3, ensure that Data Quality Objectives are considered as part of the selection process — i.e., a model should be selected before data is collected, not vice versa. 4-9 ------- Issue #6: What types of user support organization and products should be created for model users? Key Findings; • Staff need readily available support and the backing of their management in order to use models effectively. • Different types of support are needed: (1) scientific and engineering expertise on models; (2) computer expertise on how to run models; and (3) programmatic expertise on how to make decisions based on model output. • Model usage is limited by significant entry barriers - input data is often not available, data takes too much time to enter, or model documentation does not provide adequate or understandable explanations. • High turnover in Regional offices creates constant need to train new staff. Preliminary Conclusion: The focus of user support should be on meeting the training and technical support needs of the Regional offices and their contractors. There is a need for better communication channels between Headquarters (HQ), ORD, Regional office staff, and Environmental Service Divisions (ESDs). ORD should play a major role in user support. Existing modeling centers should be strengthened and new centers established with incentives to pro- actively communicate with users to document field experiences and maintain "audit trails" for models. Related Action Items: • Establish a centralized modeling support group that can interact directly with OSWER program users in the Regions and at Headquarters. Ensure that this group has sufficient resources to provide immediate response to Regional needs and has well-established communication channels with modeling experts for various media. Provide members of this group with incentives for pro-actively supporting model users and maintaining a track record of performance for specific models. 4-10 ------- Encourage Regional offices to create modeling groups that provide support for running models for a variety of program activities and communicate regularly with ORD modeling centers and OSWER support groups. Consult with Regions that have formally or informally established these types of groups (e.g., Regions HI and IV) to identify critical success factors for this approach. Ensure effective dissemination of information to model developers and users through the issuance of newsletters, maintenance of a models dearinghouse(s), and use of electronic bulletin boards. 4-11 ------- Section 5. Recommendations These recommendations are designed to improve the management and use of models for HW/SF programs in the most effective and efficient manner possible, addressing many of the management issues presented above in Section 4. The recommendations consist of a three-part action plan, incorporating many of the action items identified in Section 4. The three major task areas in the action plan are: • Task Area 1: Initiation, Additional Study, and Preparation of Management Plan • Task Area 2: Development of Guidance for Modeling • Task Area 3: Establishment of User Support Network for HW/SF Modeling Each of these is described below. Figure 5-1 provides an overview of the tasks, responsibilities and suggested sequence of events. Figure 5-2 provides initial resource estimates for completing these tasks. Task Area 1: Initiation, Additional Studies, and Preparation of Management Plan Task 1.1. Brief OSWER and ORD senior management on results of the Models Study. The objectives for this briefing are to describe past activities and project highlights, and to obtain top-level endorsement for future plans, commitment of resources, and clarification of roles and responsibilities. Responsibilities, Products: The OSWER Information Management Staff (IMS) will coordinate the preparation and presentation for these briefings, coordinating with other OSWER and ORD offices as necessary. Two products are envisioned for this task: (a) briefing slides and other materials necessary to summarize the results of the Models Study; and (b) a policy statement or similar document, issued by the OSWER and ORD AA's offices, endorsing this new effort to manage and use models more effectively and outlining key roles and responsibilities. The recipients of this memorandum will include Regional Administrators, HQ Office Directors, and HQ and Regional Division Directors. 5-1 ------- Figure 5-1 Overview of Action Plan Task Area 1 1.1 Management Briefings 1.2 Study of Model Use 1.3 Management Plan Task Area 2 2.1 Model Development, Verification and Validation Guidelines f- 2.2 Computing Alternatives Manual 2.3 Selection Guide Task Area 3 3.1 Establish Regional Modeling Groups 3.2 Define Roles, Working Agreements for Modeling Centers 3.3 Create OSWER Modeling Support Group Weeks from Start-up 8 16 24 32 40 48 56 H£-A Ij^^^^j^^^^L ^•wk m^^^ I-A-A I ±_ Organizations OSWER L L L L L P P L ORD P L L ROs P P P L P Key: Briefings, Meetings Draft Deliverable L P Deliverable Milestone Lead Participant 5-2 ------- Figure 5-2 Initial Resource Estimates Task Area 1 1.1 Management Briefings 1.2 Study of Model Use 1.3 Management Plan Task Area 2 2.1 Model Development, Verification and Validation Guidelines 2.2 Computing Alternatives Manual 2.3 Selection Guide Task Area 3 3.1 Establish Regional Modeling Groups 3.2 Define Roles, Working Agreements for Modeling Centers 3.3 Create OSWER Modeling Support Group Weeks from Start-up 8 16 24 32 40 48 56 ^ \-&r± Subtotal 1 A A 1 f V ^L h-iV-A Subtotal I ^ i _ ., ^ 1 «™ Subtotal Resources* FTIis .05 .05 .06 .16 .17 .17 .16 .5 6-15 8-10 2-3 16-28 $K 5-7 35-40 12-15 52-62 100- 150 40-45 100+ 240- 295+ TBD TBD TBD TBD FY 89 89 89 90 90 90 91/92 91/92 91/92 Notes: All estimates provided here are initial resource estimates only. More detailed estimates for Task Areas 2 and 3 will be developed under Task 1.3, the OSWER/ORD Management Plan for Models. Estimates provided here are for the tasks specified in the proposed Action Plan; overlap with other initiatives has not been fully considered. * * TBD=To Be Determined 5-3 ------- 5-4 Task 1.2. Complete an in-depth study of actual model usage in HW/SF programs, focusing on Regional users and contractors. This study will build upon the information already gathered for the models study, including the national survey of modeling conducted by Region V for the Groundwater Workstation. The study will include an historical review of cases where modeling has had significant resource impacts, both in terms of savings attributed to the use of a model and costs of applying models and performing V&V. Court cases involving disputes over models will also be reviewed, and the Office of General Counsel will be consulted to identify major legal issues related to modeling. Another key component of this study will be the identification of options for enhancing the skills and training Regional users. Responsibilities, Products: The OSWER Information Management Staff will be the lead organization for this study. Regional offices will participate in this study by supplying information about their usage of models and providing contacts for contractors. The product will be a report providing an in-depth analysis of Regional needs for models training, and identifying the most commonly used models on a program-by-program and media-by-media basis. Responsibilities, Products: The OSWER Information Management Staff will work with ORD to develop the OSWER Management Plan for Models. The plan will specify roles and responsibilities, resource requirements, and detailed time lines. Task Area 2: Development of Guidance for Modeling Task 2.1. Develop Guidelines for Model Development, Calibration, Verification, Validation, and Peer Review. This guidance will address two types of models: (a) new model development efforts that are funded by OSWER or targeted for OSWER use; and (b) existing models that are being modified for use by OSWER programs. The target audience for this guidance is model developers, within EPA and outside the Agency, who wish to promote their models for use in OSWER programs. The resulting guidance document will describe a typical model "life-cycle," addressing relevant differences for models in various media. Peer review requirements will be specified, including acceptance criteria for models (e.g., public domain software, documentation standards). For validation, particular attention will be paid to data collection issues and the relationship between validation and Data Quality Objectives (DQO). Responsibilities, Products: ORD will take the lead on developing Guidelines for Model Development, Calibration, Verification, ------- Validation, and Peer Review. The guidelines will be general enough to apply them to models for different media and pathways. Whenever possible, these guidelines will build upon existing documents addressing these issues, including direct references to other appropriate material. Task 2.2. Develop a Manual on Alternative Computing Technologies for HW/SF Models. This manual will directly complement the guidance developed under Task 2.2, providing model developers with information on the current and future state-of-the-art in computing approaches for models. The current OSWER and Agency-wide computing environments will be described in order to ensure that model developers understand hardware and software constraints from different perspectives (e.g., OSWER, ORD, OIRM/NDPD, and Regional offices). The manual may be supplemented with periodic "Technology Updates," issued semiannually or annually. The manual may also include descriptions of various "recommended" computing approaches and suggestions for maintaining model codes and distributing updated software. Responsibilities, Products: The OSWER Information Management Staff will develop the Manual on Computing Technologies for Modeling. Model developers from ORD and other sources will provide input for this manual. The Office of Information Resources Management (OIRM) will assist in reviewing the documents and provide information on Agency- wide computing trends. Task 2.3. Develop a Selection and Application Guide for Models in Hazardous Waste / Superfund Programs. This guidance will be focused on model users in the Regional offices. The Guide will provide both a media and program orientation so that the user can easily locate information on models that are appropriate for a particular type of analysis and a particular program decision. The effort to develop this Guide will include an in-depth review of the Models Inventory by modeling experts and OSWER program experts; the purpose of this will be to identify a subset of preferred or appropriate models in various categories. Responsibilities, Products: The OSWER Information Management Staff will work with the OSWER Technology Staff and appropriate ORD offices to establish a multidisciplinary project team to develop the Selection and Application Guide for Models in HW/SF programs. Development work will be coordinated with related ORD and OSWER initiatives (e.g., ATTIC, OTTRS1 Information Clearinghouse, OSWER1 s Technology Support Project). The Guide may either take the form of an automated reference tool (e.g., an expert system) or a paper-based "modeler's desk reference." The development team will include experts on models and OSWER program experts, and may include system i-_i- development personnel if an automated tool is chosen. ------- Task Area 3: Establishment of User Support Network for Hazardous Waste / Superfund Modeling. Figure 5-3 provides an overview of the user support network described below under Tasks 3.1, 3.2, and 3.3. Task 3.1. Establish a Network of Regional Modeling Groups (RMGs). These groups will act as a service bureau, providing a central pool of modeling expertise in each Region. The RMGs will be staffed by individuals with expertise in specialty areas (e.g., ground water, air, computer skills), who may be drawn from programs outside the Waste Management Division. The members should have a portion of their time dedicated to fulfilling their RMG roles. The RMGs will communicate directly with the ORD Modeling Centers and the OSWER Modeling Support Group (see below). ORD will provide the RMGs with scientific and technical expertise on how to use models, how to interpret results, and ORD will educate users on the assumptions of the models. OSWER will provide the RMGs with guidance on selecting the most appropriate model for a particular regulatory scenario and will assist the users in addressing policy and legal issues related to the use of a model. Responsibilities, Products: The Regional Offices, through the Waste Management Division, ESDs, and other Program Divisions, will have the lead for establishing the RMGs. OSWER will coordinate with the Regional Offices and define relationships between the RMGs, the ORD Modeling Centers, and the OSWER Modeling Support Group (see below). The RMGs will meet on a regular basis to discuss modeling issues, and they will actively communicate with their counterparts in other Regions. Task 3.2. Define Roles and Working Agreements With ORD Modeling Centers. The Centers should have a media orientation, reflecting the strengths of different labs in different media. The Centers will be the primary source of scientific and technical support for Regional model users. They will develop models, modify codes, add enhancements, conduct training courses, consult with users about specific modeling applications, and pro-actively monitor the field performance of the models they are supporting. Model developments in emerging areas such as exposure assessment should be encouraged within the context of this media- based organization (e.g., exposure assessments for surface water pathways). Each Center should develop its own expertise in multimedia and exposure assessment modeling, focusing especially on linking the Center's models for one media with those of a different media. The activities under this task should be coordinated with establishment of other types of ORD support for OSWER (e.g., the Alternative Treatment Technologies Information Clearinghouse). 5-6 ------- Figure 5-3 User Support Network for HIV / SF Modeling OSWER Modeling Support Group (OMSG) OMSG conveys program needs for new models to ORD, works with ORD to develop training courses, and refers user requests to appropriate ORD experts. ORD provides peer review, supports OMSG in developing guidance on model selection. OMSG supports RMGs in resolving policy and legal issues related to modeling; includes dis- seminating information an providing guidance on model selection. _L Regional Modeling Groups (RMGs) ORD provides technical and/or scientific support for RMGs; includes model documentation, training, hotline support for users, consulting, and code changes. RMGs report on performance attributes of models in the field. ORD Modeling Centers Air Multimedia and Exposure Assessment Surface Water Multimedia and Exposure Assessment Ground Water Multimedia and Exposure Assessment Drinking Water Multimedia and Exposure Assessment Science Advisory Board Resolutions on Agency-wide Modeling 5-7 ------- Responsibilities, Products: ORD, through the HW/SF Research Committee/ will establish the Modeling Centers, refining the charters of existing modeling centers as necessary to address OSWER's modeling needs. The role of these Centers is to be the "keepers of the code" and the home of modeling experts for a particular medium. They will respond to support requests from RMGs and well as OSWER (see 3.3 below). The Centers will produce new and revised models, documentation, technical assistance, and training. Task 3.3. Create an OSWER Modeling Support Group (OMSG). This group's mission is two-fold. First, it will be primarily responsible for managing the development of guidance materials on modeling and disseminating this information to users. OMSG will be a liaison between the ORD Modeling Centers and the RMGs, and its staff will be knowledgeable about all of the modeling guidance products described in Task Area 2. Second, it will provide RMGs and other users with specific policy and legal advice on model applications. This includes reporting on significant policy and legal events that affect the future use of models (e.g., court cases, new regulations) Responsibilities, Products: OSWER will take the lead in establishing OMSG, coordinating with related OPMT initiatives (e.g, the Technology Support Project, Groundwater Workstation). OMSG products will include information dissemination tools such as the OSWER Data Resource Directory, a models clearinghouse, an electronic bulletin board, or a periodic modeling newsletter. 5-8 ------- Appendices A: Interview Guide B: Interview List C: Bibliography D: OSWER Models Inventory Abbreviated ------- Appendix A Interview Guide • Information About the Interviewee Name, organization, etc. ~ Major activities of your organization ~ Involvement in modeling activities • Please describe any models used by you or your organization. — Name of Model Contact Person Model Supports Which Program(s)? Functional Description application area data used for input end products Technical Description hardware and software documentation assumptions and constraints types of calculations performed Please outline the key milestones in model building in your organization from inception through validation through use through termination. For a typical modeling project, discuss the following: ~ staffing requirements? — relationship and communication with program offices? research and technical work? A-1 ------- — review cycles? On which steps in the life cycle does your work focus? How consistent are modeling activities in terms of: — development approach? — tools (i.e., hardware and software)? • Does your group have any guidelines for model development? Do you know of any guidance documents? — If not, how do you approach the modeling effort? — If so, are the procedures followed? Which aspects are particularly valuable or not valuable? Where are the key bottlenecks or milestones which are difficult to traverse and why? Where are the greatest difficulties encountered? - research? - development? — implementation? use and interpretation? What are your suggestions for improvements to the modeling process in your organization which would increase the quality and timeliness of models while decreasing the cost and bureaucratic requirements? • What is the best example of a successful model and why was it successful? What attributes make some models unsuccessful? How can these pitfalls be avoided? A-2 ------- • Whom do you talk with or where do you go for information, assistance, or review of your modeling efforts? What results would you like to see from this effort? A-3 ------- Appendix B Interview List 1. Interviews at EPA-HO (Washington. DC) Office of Research and Development Name Date OfiFice Tom Baugh 11/30/88 OMMSQA Ray Thacker 11/17/88 OEETD Will LaVeille 12/8/88 OEPER Tom Miller 12/2/88 OHR LeeMulkey 12/15/88 A-ERL Anthony Donigian 12/15/88 Aqua Terra, Inc.(for A-ERL) Doug Ammon 12/9/88 Clean Sites, Inc. (formerly ORD) Office of Solid Waste and Emergency Response Name Meg Kelly Rich Steimle Ron Wilhelm Bill Wood Larry Zaragoza Jennifer Haley Alec McBride Zubair Saleem B-1 Date 1/26/89 11/18/88,1/26/89 2/13/89 11/30/88 11/18/88 12/2/88 12/6/88 12/7/88 Office OPMT OPMT OPMT Risk Assessment Forum OPMT OERR OSW OSW ------- Interviews at Robert S. Kerr Environment Research Laboratory. ORD (Ada. OK) Name Date Joe Williams 12/19/88 Tom Short 12/19/88 Carl Enfield 12/19/88 Dick Scalf 12/19/88 Jim Mercer 12/19/88 (GeoTrans, Inc.) 3. Interviews at International Groundwater Modeling Center. Holcomb Research Institute (Indianapolis. IN) Name Date Paul van der Heijde 12/20/88 Stan Williams 12/20/88 4. Interviews at Atmospheric Research and Exposure Assessment Lab (AREAL). ORD (Research Triangle Park. NO Name Date Gary Foley 1/11/89 Jack Shreffler 1/11/89 Bill Nelson 1/11/89 Bill Mitchell 1/11/89 Bill Peterson 1/11/89 Bruce Turner 1/11/89 B-2 ------- 5. Interviews at Air and Energy Engineering Research Lab (AEERL), ORD (Research Triangle Park. NO Name Date Bill Linak 1/11/89 6. Interviews at Office of Air Quality Planning and Standards (OAOPS). OAR (Research Triangle Park. NO Name Date Joe Tikvart 1/11/89 Joe Padgett 1/11/89 7. Interviews at Athens Environmental Research Lab (A-ERL). ORD. including the Center for Exposure Assessment Modeling (Athens, GA) Name Date Bob Ambrose 1/12/89 Dave Disney 1/12/89 (CSC) Tim Wool 1/12/89 (CSC) Craig Barber 1/12/89 Tom Barnwell 1/12/89 Dave Brown 1/13/89 B-3 ------- 8. Interviews at Risk Reduction Engineering Laboratory (RREL). ORD (Cincinnati. OH) Name Date John Convery 1/23/89 Bob Landreth 1/23/89 Dan Greathouse 1/23/89 Richard Eilers 1/23/89 Jim Goodrich 1/23/89 Jeff Adams 1/23/89 C.C. Lee 2/7/89 (via telephone) 9. Interviews at Technical Support Division. ODW (Cincinnati. OH) Name Date Jim Westrick 1/23/89 Mike Cummins 1/23/89 10. Interviews at Center for Environmental Research Information (CERI). ORD (Cincinnati. OH) Name Date Cal Lawrence 1/23/89 Clarence demons 1/23/89 Fran Kremer 1/23/89 Orville Macomber 1/23/89 B-4 ------- 11. Region HI Name Mark Garrison John Nevius Fred Sturniolo Gail Carron Mike Towle Joel Hennessey Date 2/27/89 2/27/89 2/27/89 2/27/89 2/27/89 2/27/89 Air Management Division Waste Management Division Waste Management Division Waiste Management Division Waste Management Division Waste Management Division 12. Region V Name Carol .Witt Date 2/8/89, 3/10/89 Region V, Waste Management Division (via B-5 ------- Appendix C Bibliography Policv/Manaaement/Proaram Issues PI. Briefing Slides on Modeling and Other Research at Athens ERL, November, 1988. P2. Conceptual Approach to Collecting and Managing Data for OSW, BAH. P3. "EPA's Ecological Risk Assessment Research Program, October 1985 - March 1988," Environmental Research Brief, EPA Environmental Research Laboratory, Athens, Georgia, August, 1988. P4. EPA Research Program Guide, FY '89, Office of Research and Development, September, 1988, EPA/600/9-88/017. P5. RCRA Orientation Manual. OSW/OSWER, January, 1986. P6. "Resolution on the Use of Mathematical Models by EPA for Regulatory Assessment and Decision-Making" (Draft), Science Advisory Board, December, 1988. P7. "Selection, Application, and Validation of Environmental Models," presented at the International Symposium on Water Quality Modeling of Agricultural Non- Point Sources, A.S. Donigian, Jr., Logan, Utah, June, 1988. P8. Superfund Exposure Assessment Manual P9. Superfund Risk Assessment Information Directory, OERR, November, 1986. P10. "Technology Support Project Guide for OSC/RPMs," Superfund Technology Support Project, Booz* Allen & Hamilton, Inc. Pll. "Technology Transfer and the EPA Library Network" P12. "U.S. EPA On-Scene Coordinator Communications and Computer Hardware and Software Needs: A Review," Meinhold, Moskowitz, Birnbaum, and Salgado, Brookhaven National Laboratory, OSWER, December, 1988. C-1 ------- Ground-Water Models Gl. "Agency Procedures and Criteria for the Selection and Application of Groundwater Models/' OWPE, June 21,1985. G2. "Applying the USGS Mass-transport Model (MOC) to Remedial Actions by Recovery Wells/1 Aly I. El-Kadi, IGWMQ Indianapolis, Indiana, September, 1987. G3. Background Document on Subsurface Fate and Transport Model, July, 1988. G4. Compendium of Methods to Determine Contaminated Soil Response Action Levels Based on Potential Migration to Ground Water, OERR/OSWER (by BAH), November, 1988. G5. IGWMC Ground Water Modeling Newsletter, June, 1988. G6. General Information, International Groundwater Modeling Center, Butler University, Indianapolis, IN. G7. Groundwater Requirements Study, 1988, AMS. G8. "Groundwater Flow and Transport Modeling," Leonard F. Konikow and James W. Mercer, Reston, Virginia, December, 1987. G9. Groundwater Management; the use of numerical models. (Second Edition) Paul van der Heijde, Yehuda Bachmat, John Bredenhoeft, Barbara Andrews, David Hotz, and Scott Sebastian, published by American Geophysical Union, Washington, DC, 1985. G10. "Groundwater Modeling: An Overview and Status Report," Paul K. M. van der Heijde, Aly I. El-Kadi, Stan A. Williams, IGWC, R.S. Kerr ERL, December, 1988. Gil. Interactive Simulation of the Fate of Hazardous Chemicals During Land Treatment of Oily Wastes; RTTZ User's Guide. Robert S. Kerr Environmental Research Laboratory, Ada, Oklahoma, January, 1988. G12. International Projects in Validating Ground-Water Flow and Transport Models (Abstract), U.S. NRC and Sandia National Laboratories C-2 ------- G13. "Lessons Learned from Hydrocoin and Intraval," U.S. NRC, September 20,1988. G14. Model Assessment for Delineating Wellhead Protection Areas, Final Report, Paul K.M. van der Heijde and Milovan S. Beljin, IGWMC, Indianapolis, Indiana, July, 1987. G15. "A New Annotation Database for Groundwater Models," Paul K.M. van der Heijde and Stan A. Williams, IGWMC, Indianapolis, Indiana, February, 1987. G16. "NRC Experiences in Hydrocoin: An International Project for Studying Ground- Water Flow Modeling Strategies," (Abstract) Thomas J.. Nicholson, Timothy J. McCartin, Paul A. Davis, and Walt Beyeler. G17. "OASIS: A Graphical Hypertext Decision Support System for Ground Water Contaminant Modeling," (Draft) Charles J. Newell and Philip B. Bedient, December, 1988. G18. "Price List of Publications and Services Available from IGWMC," IGWMC, Indianapolis, Indiana, December, 1988. G19. "Quality Assurance in Computer Simulations of Groundwater Contaminations, Paul van der Heijde, IGWMC, Holcomb Research Institute. G20. "Remedial Actions Under Variability of Hydraulic Conductivity," Aly I. El-Kadi, IGWMC, Indianapolis, Indiana, February, 1987. G21. Robert S. Kerr Environmental Research Laboratory: a description of the lab's history, current activities, organization, and publications; produced by ORD in Ada, Oklahoma; March, 1988. G22. "The Role of the International Ground Water Center (IGWMC) in Groundwater Modeling," Paul K.M. van der Heijde, IGWMC, Indianapolis, Indiana, 1987. G23. Selection Criteria for Mathematical Models Used in Exposure Assessments: Ground-Water Models, EPA, Office of Health and Environmental Assessment, Washington, DC, May, 1988. G24. "Simulation of Biodegradation and Sorption Processes in Ground Water," P. Srinivasan and James W. Mercer, Ground Water, July-August, 1988. C-3 ------- G25. "Standards of Performance for Investigative Methods Used in Assessing Groundwater Pollution Problems with Emphasis on the Use and Abuse of Numerical Models/' presented at the Water Pollution Control Federation Pre-Conference Workshop, James W. Mercer, GeoTrans, Inc., Herndon, Virginia, October, 1988. G26. Technical Assistance Directory, Groundwater Research, OEETD/ORD, March 27, 1987. G27. 'Testing, Verification, and Validation of Two-dimensional Solute Transport Models," Milovan S. Beljin and Paul K.M. van der Heijde, IGWMC, Indianapolis, Indiana, December, 1987. G28. U.S. EPA Ground-Water Modeling Policy Study Group: Report of Findings and Discussions of Selected Ground-Water Modeling Issues; Paul K.M. van der Heijde and Richard Park, International Ground-Water Modeling Center, Holcomb Research Institute, Butler University; November, 1986. G29. The Use of Models in Managing Ground-Water Protection Programs; Joseph F. Keely, Ph.D., Robert S. Kerr ERL, U.S. EPA, Ada, OK; January. 1987. Exposure Assessment Models El. Center for Exposure Assessment Modeling; Mr. Robert Ambrose, Jr., U.S. EPA ERL, Athens, GA E2. "Draft CEAM Policy on Support and Distribution of New Models" E3. "A Method for Testing Whether Model Predictions Fall Within a Prescribed Factor of True Values, with an Application to Pesticide Leaching," Rudolph S. Parrish and Charles N. Smith, Environmental Research Laboratory, Athens, Georgia. E4. Report on Proceedings: Aspects of Model Validation for Predictive Exposure Assessment, Risk Assessment Forum Colloquium, ORD, September 20,1988. E5. "Technical Support to Office of Solid Waste and Emergency Response and EPA Regional Offices for Multimedia Exposure Assessment Related to Remedial Action, FY88," Robert B. Ambrose, Jr., November, 1988. C-4 ------- E6. User's Guide for PCGEMS. the Personal Computer Version of the Graphical Exposure Modeling System. U.S. EPA Environmental Research Laboratory, Athens, GA; August, 1988. Air Dispersion Models Al. Environmental Research Brief: Description of UNAMAP (Version 6); D.Bruce Turner and Lucille Bender, U.S. EPA ERL, Research Triangle Park, NC; December, 1986. A2. Evaluation and Assessment of UNAMAP. R. Ernest Baumann and Rita K. Dehart, Battelle, Washington, DC, February, 1988. A3. Federal Register; Environmental Protection Agency; 40 CFR Parts 51 and 52; "Air Quality Models Guideline"; SeptemberX 9,1986. A4. Guideline on Air Quality Models (Revised); U.S. EPA Office of Air Quality Planning and Standards, Research Triangle Park, NC; July, 1986. A5. Handbook for Preparing User's Guides for Air Quality Models: William Petersen, John S. Irwin, D. Bruce Turner, Meteorology and Assessment Division, Environmental Sciences Research Laboratory, U.S. EPA, Research Triangle Park, NC; May, 1983. A6. "The NAAQS Exposure Model (NEM) Applied to Ozone," (Draft) Roy A. Paul, Ted Johnson, Anne Pope, and Alicia Ferdo, PEI Associates, Inc., Durham, North Carolina, February, 1986. A7. "Procedures for Conducting Air Pathway Analyses for Superfund Activities, Volume n, Estimation of Baseline Air Emissions at Superfund Sites," U.S. EPA Office of Air Quality Planning and Standards, Research Triangle Park, NC, February, 1989. A8. "Procedures for Conducting Air Pathway Analyses for Superfund Activities, Volume in, Estimation of Air Emissions from Clean-up Activities at Superfund Sites," U.S. EPA Office of Air Quality Planning and Standards, Research Triangle Park, NC, January, 1989. A9. "Validation of the Simulation of Human Activity and Pollutant Exposure (SHAPE) Model Using Paired Days from the Denver, CO, Carbon Monoxide Field Study," Wayne Ott, Jacob Thomas, David Mage, and Lance Wallace, February, 1987. C-5 ------- Surface Water Models SI. "Development of a Prototype Expert Advisor for the Enhanced Stream Water Quality Model QUAL2E," Thomas O. Barnwell, Jr., Linfield C. Brown, and Wiktor Marek, September, 1986. S2. "Dynamic Estuary Model Performance/' Robert B. Ambrose, Jr. and Stephen E. Roesch, February, 1982. S3. Proceedings of Stormwater and Water Quality Model Users Group Meeting (March 23-24,1987, Denver, CO); ed.by William James, University of Alabama, and Thomas Barnwell, Jr., Center for Water Quality Modeling, U.S. EPA Environmental Research Laboratory, Athens, GA; August, 1987. S4. Selection Criteria for Mathematical Models Used in Exposure Assessments; Surface Water Models. EPA, Office of Health and Environmental Assessment, July, 1987. Drinking Water Models Dl. "Feasibility of Air Stripping for Controlling Moderately Volatile Synthetic Organic Chemicals," Michael D. Cummins, James J. Westrick, and US EPA Office of Drinking Water. D2. "Packed Column Air Stripping Cost Model," Michael D. Cummins and James J. Westrick, June, 1988. D3. "Packed Column Air Stripping Preliminary Design Procedure," Michael D. Cummins and James J. Westrick, presented at 1986 Water Pollution Control Federation Conference, October, 1986. Hazardous Waste Engineering HI. "Bioremediation of Hazardous Waste Sites Workshop," a workshop brochure, EPA, Center for Environmental Research Information, Cincinnati, Ohio. H2. A Compendium of Technologies Used in the Treatment of Hazardous Wastes. EPA, Center for Environmental Research Information, Cincinnati, Ohio, September, 1987. C-6 ------- H3. Completed Interview Guide from Albert J. Klee, WMDDRD/RREL on the D-SSYS model. H4. Handbook, Remedial Action at Waste Disposal Sites (Revised), EPA, Office of Emergency and Remedial Response, Washington, DC, October, 1985. H5. "Hazardous Waste Management On the Occurrence of Transient Puffs in a Rotary Kiln Incinerator Simulator," William P. Linak, James D. Kilgroe, Joseph A. McSorley, Jost O.L. Wendt, and James E. Dunn. H6. "Mechanisms Governing Transients from the Batch Incineration of Liquid Wastes in Rotary Kilns," Jost O.L. Wendt and William P. Linak, June, 1988. H7. Modeling Remedial Actions at Uncontrolled Hazardous Waste Sites. OERR/OSWER, April, 1985. H8. "Project Summary: d-SSYS, A Computer Model for the Evaluation of Competing Alternatives," Albert J. Klee, EPA, Hazardous Waste Engineering Research Laboratory, August, 1988. H9. (Proceedings) Seminars — Requirements for Hazardous Waste Landfill Design, Construction and Closure Presentations, EPA, Center for Environmental Research Information, Cincinnati, Ohio, June, 1988. H10. "Waste Minimization Workshop, An Opportunity to Promote Waste Minimization through Auditing and Process Analysis Procedures," a workshop brochure, EPA, Center for Environmental Research Information, Cincinnati, Ohio. Hll. Waste Minimization Opportunity Assessment Manual, EPA, Center for Environmental Research Information, Cincinnati, Ohio, July, 1988. Information Technology II. "Advanced Computer Applications (ACA)", International Institute for Applied Systems Analysis (RASA), Laxenburg, Austria; March, 1988. 12. "Center for Advanced Decision Support for Water and Environmental Systems", University of Colorado, Boulder, CO. C-7 ------- Appendix D OSWER Models Inventory - Abbreviated Background The OSWER Models Inventory is a database containing information on models identified by this study. The information is not focused on the technical aspects of the model, but on usage and availability. The database contains models from each modeling category: Ground Water, Exposure Assessment, Air Dispersion, Surface Water, Hazardous Waste Engineering, and Drinking Water. The information in the database was gathered from both the interviews and the documents recommended to the project team. Type of Information in the Database The database contains a variety of information on each model, including: • Name, including the formal name, acronyms, and aliases. • Purpose, including the category, methods, and a text description. • Computer environment, including type of hardware, software used, and available documentation. • Developer information, especially who developed the model, where it was developed, and when it was completed or updated. • Distributor data, specifically whether or not the model code is available, and a source of distribution for the model and its documentation. • EPA organizations in OSWER, ORD, or elsewhere which are known to have either used the model or supported its development. Description The following lists of models were extracted from the OSWER Models database. All of the model information came from documents in the Bibliography (Appendix C). These documents can be a source of further information on these models. Model Name, Full Name — uniquely identify the model. Purpose — gives a short description of the model's function and application Developer ~ describes who developed the model. Affiliation — identifies the organization of the developer. Distributor — gives a point-of-contact for the model when the software is available for distribution. Source ~ provides the name of an organization which has further model information when the software is not available for distribution. For Further Information For further information on the OSWER Models Inventory, hardcopy or database, contact Mary Lou Melley of the Information Management Staff, OPMT, OSWER, 401 M St., SW, OS 110, Washington, DC, 20460, FTS 475-6760 ((202) 475-6760). D-1 ------- Ground Water Models 1. Model Name Full Name Purpose Developer Affiliation Source 2. Model Name Full Name Purpose Developer Affiliation Source 3. Model Name Full Name Purpose Developer Affiliation Source 4. Model Name Full Name Purpose Developer Affiliation Source 5. Model Name Full Name Purpose Developer Affiliation Source 6. Model Name Full Name Purpose Developer Affiliation Source 7. Model Name Full Name Purpose Developer Affiliation Source : AGU-1 : saturated flow ; K.R. Rushton, LM. Tomlinson : Dept. of Civil Engineering University of Birmingham : IGWMC : AGU-10 » : solute transport : I. Javandel, L. Doughty, C.F. Tsang : IGWMC Holcomb Research Institute : IGWMC :AQSIM : saturated flow : D.A. Blank : Tahal Consulting Engineers Ltd. : IGWMC :AQUIFEM i : saturated flow :G.F. Finder, CLVoss : U.S. Geological Survey Water Resources Division : IGWMC : AQUIFEM-1 : saturated flow : L.R. Towney, J.L. Wilson, A.S. Costa : Lab. for Water Resources & Hydroynamics, MIT : IGWMC ; AQUIFER : saturated flow : B. Sagar ; Anaytic and Computational Research, Inc. : IGWMC ; AQUIFLOW : saturated flow : G.T. Yeh, CW. Francis : Environmental Sciences Division Oak Ridge National Laboratory ; IGWMC D-2 ------- 8. Model Name Full Name Purpose Developer Affiliation Source 9. Model Name Full Name Purpose Developer Affiliation Source 10. Model Name Full Name Purpose Developer Affiliation Source 11. Model Name Full Name Purpose Developer Affiliation Source 12. Model Name Full Name Purpose Developer Affiliation Source 13. Model Name Full Name Purpose Developer Affiliation Source 14. Model Name Full Name Purpose Developer Affiliation Source : ASCOT : solute transport ; A.B. Gureghian : Office of Crystalline Respository Development Battelle Memorial Ins : IGWMC ; ASSP : AQUIFER SIMULATION SUBROUTINES PACKAGE : multiphase flow : Giesel, W., Schmidt, G., Trippler, K. : Bundesanstalt fur Geowissenschaften und Rohstoffe : IGWMC :BACRACK : fractured rock : Strack, O. D. L. ; Battelle Pacific Northwest Laboratories : IGWMC : BALANCE : hydrochemical ; Parkhurst, D.L., Plummer, L.N., Thorstenson, D.C. : U.S. Geological Survey, Water Resources Division : IGWMC ; BASIC GWF : saturated flow : A. Verruijt : IGWMC, Holcomb Research Institute ; IGWMC : BEAVERSOFT : solute transport : J. Bear, A. Verruijt : IGWMC Holcomb Research Institute ; IGWMC : BIDAT-HS2 : saturated flow ; P. Prudhomme, J.L. Henry, F. Biesel : Laboratoire Central D'Hydraulique De France ; IGWMC D-3 ------- 15. Model Name Full Name Purpose Developer Affiliation Source 16. Model Name Full Name Purpose Developer Affiliation Distributor 17. Model Name Full Name Purpose Developer Affiliation Source 18. Model Name Full Name Purpose Developer Affiliation Source 19. Model Name Full Name Purpose Developer Affiliation Source 20. Model Name Full Name Purpose Developer Affiliation Source 21. Model Name Full Name Purpose Developer Affiliation Source : BIO-ID • : solute transport : P. Srinivasan, J.W. Mercer : GeoTrans, Inc. : IGWMC ; BURGEAP-1 : Burgeap 7600HYSO Package : multiphase flow : D'Orval, M. douet : Burgeap : IGWMC ; BURGEAP-2 ; BURGEAP 7600HYSO (TRABICO MODEL) : saturated flow : M. Clouet, D'Orval : Burgeap : IGWMC ; BURGEAP-3 ; BURGEAP 7600 HYSO (TRABISA MODEL) : saturated flow : M. Clouet, D'Orval ; Burgeap : IGWMC :CADIL : solute transport : C.J. Emerson, B. Thomas, R.J. Luxmoore : Computer Sciences Oak Ridge National Lab. : IGWMC iCATTI : solute transport ; J.P. Sauty, W. Kinzelbach : IGWMC Holcomb Research Institute : IGWMC iCCASM : Cape Cod Aquifer System : multiphase flow : Guswa, J. H., LeBlanc, D. R. : U.S. Geological Survey : IGWMC Models D-4 ------- 22. Model Name Full Name Purpose Developer Affiliation Source :CFEST : heat transport : S.K. Gupta, C.R. Cole, C.T. Kincaid, A.M. Monti ; Water & Land Resources Division, Battelle Pacific NW Lab : IGWMC 23. Model Name Full Name Purpose Developer Affiliation Source iCFTTIM : solute transport : M.Th. van Genuchten : IGWMC Holcomb Research Institute : IGWMC 24. Model Name Full Name Purpose Developer Affiliation Source 25. Model Name Full Name Purpose Developer Affiliation Source : CHAINT ; fractured rock : Kline, N. W., England, R. L., Boca, R. C. : Rockwell International, Rockwell Hanford Operations : IGWMC :CHARGR : multiphase flow : Pritchett, J. W. : Systems, Science and Software : IGWMC 26. Model Name Full Name Purpose Developer Affiliation Source : CHEMRANK : solute transport : D.L. Nofziger, P.S.C. Rao, A.G. Hornsby : Institute of Food & Agric. Sciences University of Florida : IGWMC 27. Model Name Full Name Purpose Developer Affiliation Source 28. Model Name Full Name Purpose Developer Affiliation Source : COLUMN2 : solute transport : O.D. Nielsen, P. Bo, L. Carlsen : Chemistry Dept. Riso National Laboratory IGWMC CONS2-1D saturated flow C.S. Desai Department of Civil Engineering University of Arizona IGWMC D-5 ------- 29. Model Name Full Name Purpose Developer Affiliation Source 30. Model Name Full Name Purpose Developer Affiliation Source 31. Model Name Full Name Purpose Developer Affiliation Source 32. Model Name Full Name Purpose Developer Affiliation Source 33. Model Name Full Name Purpose Developer Affiliation Source 34. Model Name Full Name Purpose Developer Affiliation Source 35. Model Name Full Name Purpose Developer Affiliation Source : CONSOL-1 : saturated flow : K. Ueshita, K. Sato Dept. of Geotechnical Eng. Nagoya University IGWMC : CONSP(L/NL)-2D : saturated flow : C.S. Desai : Department of Civil Engineering University of Arizona : IGWMC :CRACK : fractured rock : Sudicky, E. A. : Institute for Groundwater Research, Univ. of Waterloo : IGWMC :CRREL : saturated flow : CJ. Daly : U.S. Army Corps of Engineers Cold Regions Research & Eng. Lab : IGWMC iCXTFIT • . : solute transport : J.C. Parker, M.Th. van Genuchten : Dept. of Agronomy Virginia Polytechn. Inst. and State Univ. : IGWMC :DELPET : DELPET-DISCRETE KERNEL GENERATOR : saturated flow : HJ. Morel-Seytoux, CJ. Daly, G. Peters : Engineering Research Center, Colorado State University : IGWMC : DELTA : saturated flow : H.J. Morel-Seytoux, C. Rodriquez, C. Daly, T. Illangasekare, Peters : Colorado State University Engineering Research Center : IGWMC D-6 ------- 36. Model Name Full Name Purpose Developer Affiliation Distributor 37. Model Name Full Name Purpose Developer Affiliation Distributor 38. Model Name Full Name Purpose Developer Affiliation Source 39. Model Name Full Name Purpose Developer Affiliation Source 40. Model Name Full Name Purpose Developer Affiliation Distributor 41. Model Name Full Name Purpose Developer Affiliation Source 42. Model Name Full Name Purpose Developer Affiliation Source : DELTIS : Deltis-Stream Aquifer Discrete Kernel Generator : saturated flow : H.J. Morel-Seytoux, T. Illangasekare : Engineering Research Center, Colorado State University : IGWMC DEWATER saturated flow B. Sagar Analytic and Computational Research, Inc. IGWMC DFT/C-1D : saturated flow C.S. Desai Dept. of Civil Engineering University of Arizona IGWMC : DISIFLAG : saturated flow : O. Berney : Land & Water Dev. Div. Food & Agriculture Organization : IGWMC ; DISPEQ : solute transport : H. Fluhler, W.A. Jury Swiss Federal Inst. of Research : IGWMC : DOSTOMAN : solute transport : King, Wilhite, Root Jr., Fauth, Routt, Emslie, Beckmeyer : E.I. Dupont de Nemours & Corp. Savannah River Lab. ; IGWMC ; DRAINMOD : estimate position of water table : W.R. Skaggs : Dept. of Biological and Agricultural Eng. North Carolina State Univ : IGWMC D-7 ------- 43. Model Name Full Name Purpose Developer Affiliation Source 44. Model Name Full Name Purpose Developer Affiliation Source 45. Model Name Full Name Purpose Developer Affiliation Source 46. Model Name Full Name Purpose Developer Affiliation Source 47. Model Name Full Name Purpose Developer Affiliation Source 48. Model Name Full Name Purpose Developer Affiliation Source 49. Model Name Full Name Purpose Developer Affiliation Source :DSTRAM : solute transport : P.S. Huyakorn ; HydroGeoLogic, Inc. : IGWMC : ECPL 704-F3-RO-011 : saturated flow ; F.T. Tracy : US. Army Engineer Waterways Automatic Data Processing Division : IGWMC :ECPL723-G2-L2440 : saturated flow : R.L. Cooley, J. Peters : Hydrologic Engineering Center, U.S. Army Corps of Engineers : IGWMC : EP21-GWTHERM : heat transport : A.K. Runchal, J. Treger, G. Segal : Dames and Moore Advanced Technology Group : IGWMC : EQ3NR/6 : hydrochemical : Wolary, T. J. : Lawrence Livermore National Laboratory : IGWMC : EQUILIB : hydrochemical : Morrey, J. R., Shannon, D. W. : Electric Power Research Institute : IGWMC :FE3DGW : saturated flow ; S.K. Gupta, C.R. Cole, F.W. Bond : Water & Land Resources Division Battelle Pacific NW Lab. : IGWMC D-8 ------- 50. Model Name Full Name Purpose Developer Affiliation Distributor 51. Model Name Full Name Purpose Developer Affiliation Source 52. Model Name Full Name Purpose Developer Affiliation Source 53. Model Name Full Name Purpose Developer Affiliation Distributor 54. Model Name Full Name Purpose Developer Affiliation Source 55. Model Name Full Name Purpose Developer Affiliation Distributor 56. Model Name Full Name Purpose Developer Affiliation Distributor : FEATSMF : variably saturated flow J.L. Neiber : Dept. of Agriculture Engineering, Cornell University :FEM301 : fractured rock : Kiraly, L. ; National Cooperative for Storage of Radioactive Waste-NAGRA : IGWMC ;FEMA : solute transport ; G.T. Yeh, D.D. Huff : Environmental Sci. Div. Oak Ridge National Lab. : IGWMC ; FEMSAT : saturated flow ; P.J.T. van Bakel ; Institute for Land and Water Management Research ; IGWMC ;FEMTRAN : solute transport : M.J. Martinez : Fluid Mechanics & Heat Transfer Div. Sandia National lab. : IGWMC : FEMWASTE : solute transport : G.T. Yeh, D.S. Ward : Environmental Sciences Division Oak Ridge National Lab : IGWMC : FEMWATER : variably saturated flow : G.T. Yeh, D.S. Ward : Environmental Sciences Division Oak Ridge National Lab : IGWMC D-9 ------- 57. Model Name Full Name Purpose Developer Affiliation Source 58. Model Name Full Name Purpose Developer Affiliation Source 59. Model Name Full Name Purpose Developer Affiliation Source 60. Model Name Full Name Purpose Developer Affiliation Source 61. Model Name Full Name Purpose Developer Affiliation Source 62. Model Name Full Name Purpose Developer Affiliation Source 63. Model Name Full Name Purpose Developer Affiliation Source ; FESOSPF : FINITE ELEMENT SOLUTION OF STEADY-STATE POTENTIAL FLOW PROBLEMS : saturated flow : R.L. Cooley, J. Peters : Hydrologic Engineering Center U.S. Army Corps of Engineers : IGWMC :FEWA : saturated flow ; G.T. Yeh, D.D. Huff : Environmental Sciences Division Oak Ridge National Lab : IGWMC : FIELD-2D : saturated flow : C.S. Desai : Department of Civil Engineering University of Arizona ; IGWMC . : FLAMINGO : solute transport : P.S. Huyakorn : GeoTrans, Inc. : IGWMC ;FLO : variably saturated flow : A. Vanderberg : National Hydrology Research Institute Inland Waters Directorate : IGWMC :FLOP : saturated flow : C. van den Akker : National Institute for Water Supply : IGWMC :FLOTRA : heat transport Sagar, B. : Analytic & Computational Research, Inc. : IGWMC D-10 ------- 64. Model Name Full Name Purpose Developer Affiliation Source 65. Model Name Full Name Purpose Developer Affiliation Distributor 66. Model Name Full Name Purpose Developer Affiliation Source 67. Model Name Full Name Purpose Developer Affiliation Source 68. Model Name Full Name Purpose Developer Affiliation. Source 69. Model Name Full Name Purpose Developer Affiliation Source 70. Model Name Full Name Purpose Developer Affiliation Distributor ; FLOWVEC ; variably saturated flow : R-L U, K.G. Eggert, K. Zachmann ; Simmons, Li & Associates, Inc. : IGWMC : FLUMP : variably saturated flow : T.N. Narasirnhan, S.P. Neuman ; Earth Sciences Division Lawerence Berkeley Laboratory Univ. Cailif. : IGWMC : FRACFLOW : fractured rock : Sagar, B. : Analytic & Computational Research, Inc. : IGWMC : FRACPORT : fractured rock : Deangelis, D.L., Yeh, G.T., Huff, D.D. : Oak Ridge National Laboratory : IGWMC FRACSL fractured rock Miller, J. D. Idaho National Engineering Lab. IGWMC : FRACSOL : fractured rock : Pickens, J. F. : INTERA Technologies, Inc. : IGWMC iFRACT : fractured rock : Pickens, J. F. : INTERA Technologies, Inc. : INTERA Technologies, Inc. D-11 ------- 71. Model Name Full Name Purpose Developer Affiliation Source 72. Model Name Full Name Purpose Developer Affiliation Distributor 73. Model Name Full Name Purpose Developer Affiliation Source 74. Model Name Full Name Purpose Developer Affiliation Source 75. Model Name Full Name Purpose Developer Affiliation Source 76. Model Name Full Name Purpose Developer Affiliation Source 77. Model Name Full Name Purpose Developer Affiliation Source ;FRACTEST i : fractured rock ; Karasaki, K. : Lawrence Berkeley Lab., Univ. of California : IGWMC ; FREESURF-1 i : saturated flow ; S.P. Neuman, P.A. Witherspoon : Department of Hydrology and Water Resources, University of Arizona : IGWMC : FRONT i : saturated flow : C van den Akker : National Institute for Water Supply ; IGWMC FRONTTRACK solute transport S.P. Garabedian, L.F. Konikow Water Resources Division U.S. Geological Survey IGWMC iGAFETTA : heat transport : G.F. Finder, P.E. Kinnmark, C.I. Voss : Dept. of Civil Engineering : IGWMC : GASOLINE : multiphase flow : Baehr, A. L. : U.S.G.S. Water Resources Div., National Center : IGWMC :GEOCHEM : hydrochemical : Sposito, G., Mattigod, S. V. : Department of Soil and Environmental Sciences : IGWMC D-12 ------- 78. Model Name Full Name Purpose Developer Affiliation Distributor 79. Model Name Full Name Purpose Developer Affiliation Source 80. Model Name Full Name Purpose Developer Affiliation Source 81. Model Name Full Name Purpose Developer Affiliation Distributor 82. Model Name Full Name Purpose Developer Affiliation Source 83. Model Name Full Name Purpose Developer Affiliation Source 84. Model Name Full Name Purpose Developer Affiliation Source : GEOFLOW : solute transport : S. Haji-Djafari, T.C. Wells : D'Appolonia Waste Mngmt. Services, Inc. : IGWMC :GEOTHER : multiphase flow : Faust, C. R., Mercer, J. W. : Office of Nuclear Waste Isolation, Battelle : IGWMC :GETOUT : solute transport : Burkholder, Cloninger, Dernier, Jansen, Liddell, Washburn : Nat'l Energy Software Center Argonne Natl. Laboratory : IGWMC :GGCP : Colder Groundwater Computer Package : solute transport : I. Miller, J. Marlon-Lambert : Colder Associates : IGWMC :GM5 : saturated flow : J.A. Liggett : School of Civil and Environmental Engineering Cornell University : IGWMC : GREASE-2 : heat transport : Huyakorn, P.S. : GeoTrans, Inc. : IGWMC GROMAGE saturated flow B.H. Gilding, J.W. Wesseling Delft Hydraulics Lab IGWMC D-13 ------- 85. Model Name Full Name Purpose Developer Affiliation Distributor 86. Model Name Full Name Purpose Developer Affiliation Distributor 87. Model Name Full Name Purpose Developer Affiliation Source 88. Model Name Full Name Purpose Developer Affiliation Source 89. Model Name Full Name Purpose Developer Affiliation Source 90. Model Name Full Name Purpose Developer Affiliation Distributor 91. Model Name Full Name Purpose Developer Affiliation Source iGROMULA » * : saturated flow : A.P.M. Broks, D. Dijkstra, J.W. Wesseling : Delft Hydraulics Lab ; IGWMC : GROWKWA : solute transport : J.W. Wesseling : Delft Hydraulics Lab. : IGWMC : GRWATER : variably saturated flow : D.K. Sunada : Dept. of Civil Eng. Colorado State University : IGWMC :GS2 : solute transport : L.A. Davis, G. Segol : Water, Waste and Land, Inc. : IGWMC ;GS3 i * : solute transport : L.A. Davis, G. Segol ; Water, Waste, and Land, Inc. : IGWMC :GW1 : calculation of heads for dewatering : B. Boehm : Abteilung Wasserwirtschaft Rheinbraun : IGWMC ; GWEFLOW : saturated flow : P.K.M. van der Heijde : Int'l Ground Water Modeling Ctr. Holcomb Research Institute : IGWMC D-14 ------- 92. Model Name Full Name Purpose Developer Affiliation Source 93. Model Name Full Name Purpose Developer Affiliation Source 94. Model Name Full Name Purpose Developer Affiliation Source 95. Model Name Full Name Purpose Developer Affiliation Distributor 96. Model Name Full Name Purpose Developer Affiliation Source 97. Model Name Full Name Purpose Developer Affiliation Source 98. Model Name Full Name Purpose Developer Affiliation Source ; GWMD-3 : GWMD3-APPROPRIATION MODEL : saturated flow : D.G. Jorgensen, H. Grubb, C.H. Bakerjr., G.E. Hilmes, E.D. Jenkins : U.S. Geological Survey Water Research Dept. University of Kansas : IGWMC : GWPATH : saturated flow : J.M. Shafer : Illinois State Water Survey Ground Water Section : IGWMC : GWSIM : saturated flow : T.R. Knowles : Texas Department of Water Resources : IGWMC : GWSIM-2 : solute transport : T.R. Knoles : Texas Dept. of Water Res. : IGWMC : GWUSER : saturated flow : C.R. Kolterman : Water Resources Center Desert Research Inst. Univ. of Nevada System : IGWMC HOTWTR heat transport J.E. Read U.S. Geological Survey IGWMC : HSSWDS : variably saturated flow : E.R. Perrier, A.C. Gibson ; Solid & Hazardous Waste Research Div. Municipal Env. Research Lab. : IGWMC D-15 ------- 99. Model Name Full Name Purpose Developer Affiliation Source 100. Model Name Full Name MODEL Purpose Developer Affiliation Source 101. Model Name Full Name Purpose Developer Affiliation Source 102. Model Name Full Name Purpose Developer Affiliation Source 103. Model Name Full Name Purpose Developer Affiliation Source 104. Model Name Full Name Purpose Developer Affiliation Distributor 105. Model Name Full Name Purpose Developer Affiliation Source ;HST3D : heat transport ; K.L. Kipp : U.S. Geological Survey and IGWMC ; IGWMC ; IASIPMAM : ITERNATIVE ALGOITHM SOLVING INVERSE PROBLEM MULTICELL AQUIFER : saturated flow : Y. Bachmat, A. Dax : Hydrological Service of Israel : IGWMC :IDPNGM : I.D.P.N.G.M. : saturated flow : V. Guvanasen : Dept. of Civil & System Engineer. James Cook Univ. North Queenlands : IGWMC :INFGR : variably saturated flow : P.M. Craig, E.G. Davis Environmental Science Division Oak Ridge Nat'l Laboratory : IGWMC : INFIL : variably saturated flow : M. Vauclin : Institute De Mecanique De Grenoble ; IGWMC : INFIL : variably saturated flow : A.I. El-Kadi : IGWMC, Holcomb Research Institute : IGWMC : INTERFACE i : multiphase flow : Page, R. H. : Water Resources Program, Princeton University : IGWMC D-16 ------- 106. Model Name Full Name Purpose Developer Affiliation Source 107. Model Name Full Name Purpose Developer Affiliation Source 108. Model Name Full Name Purpose Developer Affiliation Source 109. Model Name Full Name Purpose Developer Affiliation Source 110. Model Name Full Name Purpose Developer Affiliation Distributor 111. Model Name Full Name Purpose Developer Affiliation Distributor 112. Model Name Full Name Purpose Developer Affiliation Source : INVERS : saturated flow : W.I.M. Elderhorst : Institute for Applied Geosciences : IGWMC : IONMIG : solute transport : A.J. Russon : Fluid Mechanics & Heat Transfer Division Sandia National Lab. : IGWMC : ISL-50 : solute transport : R.D. Schmidt : U.S. Dept. of the Interior Bureau of Mines : IGWMC : ISOQUAD ; saturated flow : G.F. Pinder, E.O. Frind ; Department of Civil Engineering Princeton University : IGWMC : ISOQUAD-2 : solute transport : G.F. Pinder : Dept. of Civil Eng. Princeton University : IGWMC :KRGW i : saturated flow : H.N. Tyson : Food and Agriculture Organization, United Nations : IGWMC LAFTID saturated flow I. Herrera, J.P. Hennart, R. Yates Intituto De Geofisica Ciudad Universitaria IGWMC D-17 ------- 113. Model Name Full Name Purpose Developer Affiliation .Source 114. Model Name Full Name Purpose Developer Affiliation Source 115. Model Name Full Name Purpose Developer Affiliation Source 116. Model Name Full Name Purpose Developer Affiliation Source 117. Model Name Full Name Purpose Developer Affiliation Source 118. Model Name Full Name Purpose Developer Affiliation Distributor 119. Model Name Full Name Purpose Developer Affiliation Source iLANDFIL i : variably saturated flow : G.P. Korfiatis : Civil and Environmental Engineering Rutgers University ; IGWMC : LAS : LEAKY AQUIFER SIMULATION : saturated flow : T. Maddock : Water Resources Dev. & Mgt. Svc. Land & Water Dev.Org. Food & Agric : IGWMC MAGNUM-2D heat transport : England, R.L., Mine, M.W., Ebblad, K.J., Bace, R.G. : Rockwell Hanford Operations ; IGWMC :MAQWF : saturated flow ; D.N. Contractor, S.M.A. El Didy, A.S. Ansary : Department of Civil Engineering University of Arizona : IGWMC ; MAQWQ : solute transport : D.N. Contractor, S.M.A. El Didy, A.S. Ansary ; Dept. of Civil Sc Mechanical Engineering University of Arizona : IGWMC MARIAH heat transport D.K. Gartling Sandia Nat'l Labs IGWMC :MATTUM : heat transport : Yeh, G. T. & Luxmoore, R. J. : Environmental Sci. Div., Oak Ridge National Lab : IGWMC D-18 ------- 120. Model Name Full Name Purpose Developer Affiliation Source 121. Model Name Full Name Purpose Developer Affiliation Source 122. Model Name Full Name Purpose Developer Affiliation Distributor 123. Model Name Full Name Purpose Developer Affiliation Source 124. Model Name Full Name Purpose Developer Affiliation Distributor 125. Model Name Full Name Purpose Developer Affiliation Source 126. Model Name Full Name Purpose Developer Affiliation Source : MINEQL2 » ; hydrochemical : Westall, J. C, Zachary, J. L., Morel, F. M. M. : Dept. of Civil Engineering, Mass. Institute of Technology : IGWMC ;MMT-1D : heat transport ; F.E. Kaszeta, C.S. Simmons, C.R. Cole ; Battelle Pacific NW Labs : IGWMC MMT-DPRW heat transport S.W. Ahistrom, H.P. Foote, R.J. Serne Battelle Pacific NW Labs IGWMC : MODFLOW : saturated flow : M.G. McDonald, A.W. Harbaugh ; Ground Water Branch, WRD U.S. Geological Survey ; IGWMC : MOTGRO : multiphase flow : Van Der Veer, P. : Rijkswaterstaat, Data Processing Division : IGWMC : MOTIF : fractured rock : Guvanasen, V. : AECL Whiteshell Nuclear Research Establishment : IGWMC iMULKOM ; multiphase flow : Pruess, K. : Lawrence Berkeley Lab ; IGWMC D-19 ------- 127. Model Name Full Name Purpose Developer Affiliation Source 128. Model Name Full Name Purpose Developer Affiliation Source 129. Model Name Full Name Purpose Developer Affiliation Source 130. Model Najne Full Name Purpose Developer Affiliation Source 131. Model Name Full Name Purpose Developer Affiliation Source 132. Model Name Full Name Purpose Developer Affiliation Source 133. Model Name Full Name Purpose Developer Affiliation Source iMUSHRM : multiphase flow ; Pritchett, J. W. : Systems, Science and Software : IGWMC :MUST : variably saturated flow : P.J.M. Delaat : International Inst. for Hydraulic and Environm. Engineering iIGWMC iNETFLOW : fractured rock ; Pahwa, S. B., Rama Rao, B. S. ; Office of Nuclear Waste Isolation, Battelle : IGWMC iNTTROSIM : solute transport : P.S.C. Rao : Soil Science Dept. University of Florida : IGWMC iNLRGFM : NON-LINEAR REGRESSION GROUNDWATER FLOW MODEL : saturated flow : R.L. Cooley, R.L. Naff : U.S. Geological Survey Water Resources Division ; IGWMC : NMFD-3D N.M.F.D.3D : saturated flow D.R. Posson, G.A. Hearne, J.V. Tracy, P.F. Frenzel ; U.S. Geological Survey : IGWMC : NMODEL : solute transport : H.M. Selim, J.M. Davidson : Louisana Agricultural Experiment Station Louisana State University ; IGWMC D-20 ------- 134. Model Name Full Name Purpose Developer Affiliation Source 135. Model Name Full Name Purpose Developer Affiliation Source • 136. Model Name Full Name Purpose Developer Affiliation Source 137. Model Name Full Name Purpose Developer Affiliation Source 138! Model Name Full Name Purpose Developer Affiliation Source 139. Model Name Full Name Purpose Developer Affiliation Source 140. Model Name Full Name Purpose Developer Affiliation Source : ONE STEP : variably saturated flow : J.B. Kool, J.C. Parker, M.Th. van Genuchten : 245 Smyth hall Va. Polytechnic Inst. : IGWMC :ONE-D : solute transport : M.Th. van Genuchten, W.J. Alves ; IGWMC Holcomb Research Institute : IGWMC : PATHS : solute transport : R.W. Nelson : Battelle Pacific NW Labs : IGWMC :PE : PARAMETER ESTIMATION PROGRAM : saturated flow : J.V. Tracy : U.S. Geological Survey Water Resources Dept. National Center : IGWMC :PEP : saturated flow : D.E. Evenson : CDM Water Resources Engineers : IGWMC : PHREEQE : hydrochemical : Parkhurst, D. L., Thorstenson, D. C, Plummer, L. N. : U.S. Geological Survey, Wter Resources Division ; IGWMC : PISTON : solute transport : H. Fluhler, W.A. Jury ; Swiss Federal Inst. of Research : IGWMC D-21 ------- 141. Model Name Full Name Purpose Developer Affiliation Distributor 142. Model Name Full Name Purpose Developer Affiliation Source 143. Model Name Full Name Purpose Developer Affiliation Source 144. Model Name Full Name Purpose Developer Affiliation Source 145. Model Name Full Name Purpose Developer Affiliation Source 146. Model Name Full Name Purpose Developer Affiliation Source 147. Model Name Full Name Purpose Developer Affiliation Source : PLASM : saturated flow : T.A. Prickett, CG. Lonnquist : Consulting Water Resource Engineers : IGWMC :PUN : saturated flow : A. Levassor : Centre D'lnformatique Geologique Ecol Des Mines De Paris : IGWMC ; PLUME-2D : solute transport : P.K.M. van der Heijde : IGWMC Holcomb Research Institute : IGWMC ; PORFLOW : heat transport : Kline, N. W., Runchal, A. K., Baca, R. G. : Energy Systems Group, Rockwell International ; IGWMC ; PORFLOW H : solute transport : A.K. Runchal : Analytic & Computational Research, Inc. : IGWMC iPORFREEZE » : heat transport : Runchal, A. K. : Analytic & Computational Research, Inc. : IGWMC : PROTOCOL : hydrochemical ; Pickrell, G., Jackson, D. D. ; Lawrence Livermore National Laboratory : IGWMC D-22 ------- 148. Model Name Full Name Purpose Developer Affiliation Source 149. Model Name Full Name Purpose Developer Affiliation Distributor 150. Model Name Full Name Purpose Developer Affiliation Source 151. Model Name Full Name Purpose Developer Affiliation Source 152. Model Name Full Name Purpose Developer Affiliation Source 153. Model Name Full Name Purpose Developer Affiliation Distributor 154. Model Name Full Name Purpose Developer Affiliation Source :PT : heat transport : Bodvarsson, A. S. : Lawrence Berkeley Lab., University of California : IGWMC :PT/CCC : heat transport : M.J. Lippman, T.N. Naraimhan, D.C. Mangold, G.S. Bodvarsson : Nat'l Energy Software Center Argonne Nat'l Lab. : IGWMC :PUMPTEST : saturated flow : M.S. Beljin : IGWMC, Holcomb Research Institute : IGWMC : QTDMA : Quasi Three-Dimensional Multi-Aquifer Model : saturated flow : J.B. Weeks : U.S. Geological Survey Water Resources Division : IGWMC RADFLOW saturated flow K.S. Rathod, K.R. Rushton Int'l Ground Water Modeling Center Holcomb Research Institute IGWMC : RANDOM WALK ; solute transport : T.A. Prickett, T.G. Naymik, C.G. Lonnquist : 111. State Water Survey : IGWMC : REDEQL-UMD : hydrochemical : Harriss, D.K., Ingle, S.E., Taylor, D.K., Magnuson, V.R. : Dept. of Chemistry, University of Minnesota : IGWMC D-23 ------- 155. Model Name Full Name Purpose Developer Affiliation Source 156. Model Name Full Name Purpose Developer Affiliation Distributor 157. Model Name Full Name Purpose Developer Affiliation Source 158. Model Name Full Name Purpose Developer Affiliation Source 159. Model Name Full Name Purpose Developer Affiliation Source 160. Model Name Full Name Purpose Developer Affiliation Distributor 161. Model Name Full Name Purpose Developer Affiliation Source : REDEQL.EPA : hydrochemical : Ingle, S.E., Schuldt, M.D., Schults, D.W. : Hatfield Marine Sci. Cntr., U.S. EPA : IGWMC :RESTOR : solute transport ; J.W. Warner : Civil Engineering Dept. Colorado State Univ. : IGWMC :RTTZ : solute transport : D.L. Nofziger, J.R. Williams. T.E. Short ; Robert S. Karr Environmental Research Lab U.S. EPA : IGWMC : ROCMAS-H : fractured rock : Noorishad, J., Witherspoon, P. A. : Lawrence Berkeley Laboratory, Univ. of California : IGWMC : ROCMAS-HM : fractured rock : Noorishad, J., Ayatollahi, M. S., Witherspoon, P. A. : Lawrence Berkeley Laboratory, Univ. of California ; IGWMC : ROCMAS-HS i : fractured rock : Noorishad, J., Mcnran, M. ; Lawrence Berkeley Laboratory, Univ. of California : IGWMC : ROCMAS-HW : saturated flow ; J. Noorishad, M.S. Ayatollahi, P.A. Witherspoon : Earth Sciences Division Lawrence Berkeley Lab. Univ. of California : IGWMC D-24 ------- 162. Model Name Full Name Purpose Developer Affiliation Source 163. Model Name Full Name Purpose Developer Affiliation Source 164. Model Name Full Name Purpose Developer Affiliation Source 165. Model Name Full Name Purpose Developer Affiliation Source 166. Model Name Full Name Purpose Developer Affiliation Source 167. Model Name Full Name Purpose Developer Affiliation Source 168. Model Name Full Name Purpose Developer Affiliation Source : ROCMAS-THM : fractured rock : Noorishad, J., Witherspoon, P. A. : Lawrence Berkeley Lab., Univ. of California : IGWMC :SANGRE : heat transport : Anderson, CA. : Los Alamos Nat'l. Lab. : IGWMC ; SATRA-CHEM : solute transport : P.M. Lewis, C.I. Voss, J. Rubin : U.S. Geological Survey National Center : IGWMC : SATURN-2 : solute transport : P. Huyakom : GeoTrans, Inc. : IGWMC : SBIR ; solute transport : R.M. Li : Simous, Li & Assoc., Inc. : IGWMC : SCHAFF : heat transport : M.L. Sorey, M.J. Lippman : Nat'l Energy Software Center Argonne Nat'l Lab : IGWMC : SEAWTR : multiphase flow : Allayla, R. I. : Civil Eng. Dept, Colorado State Univ. : IGWMC D-25 ------- 169. Model Name Full Name Purpose Developer Affiliation Source 170. Model Name Full Name Purpose Developer Affiliation Source 171. Model Name Full Name Purpose Developer Affiliation Distributor 172. Model Name Full Name Purpose Developer Affiliation Source 173. Model Name Full Name Purpose Developer Affiliation Source 174. Model Name Full Name Purpose Developer Affiliation Source 175. Model Name Full Name Purpose Developer Affiliation Source ; SEEP(VM)-3D saturated flow C.S. Desai : Department of Civil Engineering University of Arizona :IGWMC : SEEP2(VM)-2D : saturated flow : C.S. Desai : Department of Civil Engineering University of Arizona iIGWMC ;SEEPV : variably saturated flow : L.A. Davis : Water, Waste and Land, Inc. : IGWMC :SEFTRAN : heat transport : Huyakorn, P.S. : GeoTrans, Inc. : IGWMC ; SESOIL : solute transport : M. Bonazountas, J.M. Wagner : Office of Toxic Substances U.S. EPA : IGWMC :SGMP : S.G.M.P. : saturated flow : J. Boonstra : Inter'l Inst. for Land Reclamation and Improvement : IGWMC : SHAFT-79 : heat transport : K. Pruess, R.C. Schroeder : Nat'l Energy Software Center Argonne Nat'l Lab : IGWMC D-26 ------- 176. Model Name Full Name Purpose Developer Affiliation Source 177. Model Name Full Name Purpose Developer Affiliation Distributor 178. Model Name Full Name Purpose Developer Affiliation Source 179. Model Name Full Name Purpose Developer Affiliation Distributor 180. Model Name Full Name Purpose Developer Affiliation Source 181. Model Name Full Name Purpose Developer Affiliation Source 182. Model Name Full Name Purpose Developer Affiliation Source : SHALT : heat transport : J.F. Pickens, G.E. Grisak : INTERA Technologies, Inc. : IGWMC : SICK-100 : saturated flow : G. Schmid ; Ruhr-University Bochum Institute F. Konst. Ingenieubau AGIV : IGWMC ;SOIL : variably saturated flow : A.I. El-Kadi : Int'l Ground Water Modeling Center Holcomb Research Institute ; IGWMC ; SOILMOP : variably saturated flow : D.L. Ross, HJ. Morel-Seytoux ; Dept. of Civil Eng. Colorado State University : IGWMC : SOLMNEQ : hydrochemical : Kharaka, Y. K., Barnes, I. U.S. Geological Survey, MS/427 : IGWMC : SOLMNQ : hydrochemical : Goodwin, B. W., Munday, M. : Atomic Energy of Canada Ltd., Whiteshell Nuc. Res. Establishment : IGWMC : SOLUTE : solute transport : M.S. Beljin : IGWMC Holcomb Research Institute : IGWMC D-27. ------- 183. Model Name Full Name Purpose Developer Affiliation Source 184. Model Name Full Name Purpose Developer Affiliation Source 185. Model Name Full Name Purpose Developer Affiliation Distributor 186. Model Name Full Name Purpose Developer Affiliation Source 187. Model Name Full Name Purpose Developer Affiliation Source 188. Model Name Full Name Purpose Developer Affiliation Source 189. Model Name Full Name Purpose Developer Affiliation Source ;SOMOF : variably saturated flow : J.W. Wesseling : Delft Hydraulics Laboratory : IGWMC SOTRAN solute transport I.L. Nwaogazie I.L. Nwaogazie Dept. of Civil Eng. Univ. of Port Harcourt IGWMC : SPLASHWATR : heat transport : Milly, P.C.D. : Massachusetts Inst. of Technology, Dept. of Civil Eng. : IGWMC :ST-2D ; saturated flow ; A.I. El-Kadi ; Int'l Ground Water Modeling Ctr. Holcomb Research Inst. Butler Univ : IGWMC STAFAN-2 fractured rock Huyakorn, P.S. Office of Nuclear Waste Isoliation, Battelle IGWMC : STAFF-2D : fractured rock : Huyakorn, P. S. : HydroGeoLogic, Inc. : IGWMC iSTFLO : saturated flow : C.R. Faust, T. Chan, B5. Ramada, B.M. Thompson : Performance Assest. Dept.of Nucl. Water Isolation Battelle Prj. Mgt : IGWMC D-28 ------- 190. Model Name Full Name Purpose Developer Affiliation Source 191. Model Name Full Name Purpose Developer Affiliation Source 192. Model Name Full Name Purpose Developer Affiliation Source 193. Model Name Full Name Purpose Developer Affiliation Source 194. Model Name Full Name Purpose Developer Affiliation Source 195. Model Name Full Name Purpose Developer Affiliation Source 196. Model Name Full Name Purpose Developer Affiliation Source ; STRESEEP-2D : saturated flow : C.S. Desai : Department of Civil Engineering University of Arizona ; IGWMC : SUGARWAT : fractured rock : Holditch, S. A., and Associates : U.S. Dept. of Energy, Morgantown Energy Technology Center : IGWMC :SUTRA : heat transport ; Voss, C. I. : U.S. Geological Survey : IGWMC : SWANFLOW : multiphase flow : Faust, C. R., Rumbaugh, J. D. : GeoTrans, Inc. : IGWMC ; SWATRE : variably saturated flow : R.A. Feddes ; Inst. for Land and Water Management Research ; IGWMC : SWENT : heat transport : INTERA, Inc. : INTERA Technologies, Inc. : IGWMC SWIFT heat transport Dillion, R.T., Cranwell, R.M., Lantz, R. B., Pahwa, S.B., Reeves M. Argonne National Lab. IGWMC D-29 ------- 197. Model Name Full Name Purpose Developer Affiliation Source 198. Model Name Full Name Purpose Developer Affiliation Source 199. Model Name Full Name Purpose Developer Affiliation Source 200. Model Name Full Name Purpose Developer Affiliation Source 201. Model Name Full Name Purpose Developer Affiliation Distributor 202. Model Name Full Name Purpose Developer Affiliation Distributor 203. Model Name Full Name Purpose Developer Affiliation Source ; SWIFT : multiphase flow Verruijt, A., Can, J. B. S. : Technical University of Delft, Department of Civil Engineering : IGWMC : SWIGS-2D : multiphase flow : Contractor, D. N. : Water and Energy Research Inst. of the Western Pacific, U. of Guam : IGWMC :SWIM : multiphase flow : Sada Costa, A. A. G., Wilson, J. L. : Lab. for Water Resources and Hydrodynamics, MIT ; IGWMC : SWIPR : solute transport : INTERA Environmental Consult., Inc. : U.S. Geological Survey Denver Federal Center : IGWMC : SWSOR » : multiphase flow : Mercer, J. W., Faust, C R. : GeoTrans, Inc. : IGWMC SYLENS saturated flow H.M. Haitjema, O.D.L. Strack School of Public & Environmental Affairs Indiana University IGWMC : TERZAGI : saturated flow : T.R. Narasimhan : National Energy Software Center (NESC), Argonne National Laboratory : IGWMC D-30 ------- 204. Model Name Full Name Purpose Developer Affiliation Source 205. Model Name Full Name Purpose Developer Affiliation Source 206. Model Name Full Name Purpose Developer Affiliation Source 207. Model Name Full Name Purpose Developer Affiliation Source 208. Model Name Full Name Purpose Developer Affiliation Source 209. Model Name Full Name Purpose Developer Affiliation Source 210. Model Name Full Name Purpose Developer Affiliation Distributor :TETRA : saturated flow : L.A. Abriola, G.F. Finder : Int'l Ground Water Modeling Center Holcomb Research Institute : IGWMC : TEXASHEAT : heat transport : Grubaugh, E. K., Reddell, D. L. Texas Water Res. Inst, Texas A&M Univ. IGWMC iTGUESS : saturated flow : K.R. Bradbury, E.R. Rothschild ; Int'l Ground Water Modeling Center Holcomb Research Institute : IGWMC : THCVFIT : saturated flow : P.K.M. van der Heijde ; Int'l Ground Water Modeling Center Holcomb Research Institute : IGWMC : THWELLS : saturated flow : P.K.M. van der Heijde : IGWMC, Holcomb Research Institute : IGWMC :TIMLAG : saturated flow : D.B. Thompson : IGWMC, Holcomb Research Institute : IGWMC : TOFEM-N : saturated flow : T.N. Olsthoorn : Nansenlael W. : IGWMC D-31 ------- 211. Model Name Full Name Purpose Developer Affiliation Source 212. Model Name Full Name Purpose Developer Affiliation Source 213. Model Name Full Name Purpose Developer Affiliation Source 214. Model Name Full Name Purpose Developer Affiliation Source 215. Model Name Full Name Purpose Developer Affiliation Distributor 216. Model Name Full Name Purpose Developer Affiliation Source 217. Model Name Full Name Purpose Developer Affiliation Source : TOUGH t : fractured rock : Pruess, K., Tsang, Y. W., Wang, J. S. Y. : Lawrence Berkeley Laboratory, University of California : IGWMC ; TRACR-3D : fractured rock ; Travis, B. J. : Los Alamos National Laboratory ; IGWMC : TRAFRAP-WT : fractured rock : Huyakorn, P. S., White, H. O., Wadsworth, T. D. : Holcomb Research Institute : IGWMC TRANQL ; solute transport ; G.A. Cederberg, R.L. Street, J.O. Leckie : Los Alamos National Lab. ; IGWMC : TRANS : heat transport : W.R. Walker, J.D. Sabey : Water Resources Research Ctr. Virginia Polytechnic Institute : IGWMC TRIGAT-HSI saturated flow P. Prudhomme, J.L. Henry, F. Biesel Laboratoire Central D'Hydraulic De France IGWMC ;TRIPM : solute transport : A.B. Gureghian : ONWI, Battelle Memorial Institute : IGWMC D-32 ------- 218. Model Name Full Name Purpose Developer Affiliation Source 219. Model Name Full Name Purpose Developer Affiliation Source 220. Model Name Full Name Purpose Developer Affiliation Source 221. Model Name Full Name Purpose Developer Affiliation Source 222. Model Name Full Name Purpose Developer Affiliation Source 223. Model Name Full Name Purpose Developer Affiliation Distributor 224. Model Name Full Name Purpose Developer Affiliation Distributor : TRUCHN/ZONE : fractured rock : Resmuson, A., Neretnieks, I. : Royal Institute of Technology : IGWMC ; TRUMP : fractured rock : Edwards, A.L., Rasmuson, A., Neretnieks, I., Narasimhan, T.N. : Royal Inst. of Technology : IGWMC TRUST : variably saturated flow T.N. Narasimhan : Water and Land Resources Division Battelle Pacific NW Lab. : IGWMC : TSSLEAK : saturated flow : P.M. Cobb, C.D. Mcelwee, M.A. Butt : Kansas Geological Survey, University of Kansas : IGWMC : TSSLEAK : saturated flow : P.K.M. van der Heijde ; IGWMC Holcomb Research Institute : IGWMC : UNSAT-1 ; variably saturated flow : M. Th. van Genuchten : U.S. Salinity Lab U.S. Dept. of Agriculture ; IGWMC : UNSAT-1D : variably saturated flow : S.K. Gupta, C.S. Simmons : Battelle Pacific NW Labs : IGWMC D-33 ------- 225. Model Name Full Name Purpose Developer Affiliation Distributor 226. Model Name Full Name Purpose Developer Affiliation Source 227. Model Name Full Name Purpose Developer Affiliation Distributor 228. Model Name Full Name Purpose Developer Affiliation Distributor 229. Model Name Full Name Purpose Developer Affiliation Source 230. Model Name Full Name Purpose Developer Affiliation Source 231. Model Name Full Name Purpose Developer Affiliation Source ; UNSAT-2 i : variably saturated flow : S.P. Neuman : Dept. of Hydrology and Water Resources Univ. of Arizona : IGWMC : UNSAT-H : variably saturated flow : MJ. Payer, G.W. Gee : Battelle Pacific Northwest Lab : IGWMC : USGS-2D-FLOW : saturated flow : P.C. Trescott, G J. Finder, S.P. Larson : VS. Geological Survey Branch of Groundwater : IGWMC : USGS-2D-TRANSPORT/MOC : solute transport : L.F. Konilow, J.D. Bredehoeft : U.S. Geological Survey : IGWMC : USGS-3D-FLOW i : saturated flow : P.C Trescott, S.P. Larson : US. Geological Survey Branch of Groundwater : IGWMC : UWIS-2D-TRANSPORT : heat transport : C.B. Andrews : Woodward-Clyde Cnslt. : IGWMC :VADOSE » : heat transport : Sagar, B. ; Analytic & Computational Research, Inc. : IGWMC D-34 ------- 232. Model Name Full Name Purpose Developer Affiliation Source 233. Model Name Full Name Purpose Developer Affiliation Source 234. Model Name Full Name Purpose Developer Affiliation Source 235. Model Name Full Name Purpose Developer Affiliation Source 236. Model Name Full Name Purpose Developer Affiliation Source 237. Model Name Full Name Purpose Developer Affiliation Source 238. Model Name Full Name Purpose Developer Affiliation Source : VAM-2D : solute transport : P.S. Huyakorn : HydroGeoLogic, Inc. : IGWMC : VAM-3D : solute transport : P.S. Huyakorn : HydroGeoLogic, Inc. : IGWMC : VARQ ; saturated flow : M.A. Butt, C.D. McElwee : Int'l Ground Water Modeling Center Holcomb Research Institute : IGWMC :VDM : VARIABLE DENSITY MODEL : saturated flow : L.K. Kuiper : U.S. Geological Survey : IGWMC : VS-2D : variably saturated flow : E.G. Lappala, R.W. Healy, E.P. Weeks : U.S. Geological Survey Denver Federal Center : IGWMC VTT : saturated flow : A.E. Reisenaurer, C.R. Cole : Water & Land Resources Division Battelle Pacific NW Lab. : IGWMC : VTTSS-2 : saturated flow : A.E. Reisenauer, C.R. Cole : Water & Land Resources Division Battelle Pacific NW Lab. ; IGWMC 0-35 ------- 239. Model Name Full Name Putpose Developer Affiliation Source 240. Model Name Full Name Purpose Developer Affiliation Source 241. Model Name Full Name Purpose Developer Affiliation Distributor 242. Model Name Full Name Purpose Developer Affiliation Source 243. Model Name Full Name Purpose Developer Affiliation Source 244. Model Name Full Name Purpose Developer Affiliation Source 245. Model Name Full Name Purpose Developer Affiliation Source : VTTSS-3 : saturated flow ; A.E. Reisenauer, C.R. Cole Water & Land Resources Division Battelle Pacific NW Lab. : IGWMC : WALTON-35 : solute transport : W.C. Walton : IGWMC Holcomb Research Institute : IGWMC ; WASTE : solute transport : B. Ross, CM. Koplik : Analytical Sciences Corp. Energy & Environment Div. ; IGWMC : WATEQ-2 : hydrochemical ; Ball, J. W., Jenne, E. A., Nordstrom, D. K. ; U.S. Geological Survey : IGWMC : WATEQ-3 > : hydrochemical : Ball, J. W., Jenne, E. A., Cantrell, M. W. : US. Geological Survey, MS/21 : IGWMC : WATEQF i : hydrochemical : Plummer, L. M., Jones, B. F., Truesdell, A. H. : U.S. Geological Survey, Water Resources Division : IGWMC : WATERFLO : variably saturated flow : D.L. Nofziger : Institute of Food & Agriculture Sciences University of Florida : IGWMC D-36 ------- Exposure Assessment Models 1. Model Name Full Name Purpose Developer Affiliation Distributor 2. Model Name Full Name Purpose Developer Affiliation Distributor 3. Model Name Full Name Purpose Developer Affiliation Distributor 4. Model Name Full Name Purpose Developer Affiliation Distributor 5. Model Name Full Name Purpose Developer Affiliation Distributor 6. Model Name Full Name Purpose Developer Affiliation Distributor 7. Model Name Full Name Purpose Developer Affiliation Distributor : DYNHYD-4 : Dynamic Estuary Model : flow, transport, and degradation in rivers and estuaries ; Feigner, K.D., Harris, H.S. : Federal Water Quality Administration, U.S. Dept. of Interior : David Disney, CEAM :DYNTOX : Dynamic Toxicity Model : predict concentrations of contaminants in surface waters : Limno-Tech : David Disney, CEAM :EXAMS-2 : Exposure Analysis Modeling System, Version 2.92 : predict concentrations of contaminants in surface water : Burns, L.A., Cline, D.M., Lassiter, R.R. : U.S. EPA, ERL-Athens, GA : David Disney, CEAM :FGETS : Food and Gill Exchange of Toxic Substances : predict bioaccumulation of nonpolar organic pollutants in fish David Disney, CEAM :GEMS : Graphical Exposure Modeling System : air, soil, and groundwater analysis : ERL-Athens, GA : Russell Kinerson, EPA OTS, (202) 382-3928 :HSPF : Hydrological Simulation Program - FORTRAN : predict contaminant concentrations in runoff, surface, ground water • U.S. EPA, ERL-Athens, GA : David Disney, CEAM : MINTEQA-2 : Equilibrium Metal Speciation Model : predict concentrations of contaminants in surface and ground waters : Felmy, A.R., Girvin, D.C., and Jenne, E.A. : U.S. EPA, ERL-Athens, GA : David Disney, CEAM D-37 ------- 8. Model Name Full Name Purpose Developer Affiliation Distributor 9. Model Name Full Name Purpose Developer Affiliation Distributor 10. Model Name Full Name Purpose Developer Affiliation Distributor 11. Model Name Full Name Purpose Developer Affiliation Distributor 12. Model Name Full Name Purpose Developer Affiliation Distributor 13. Model Name Full Name Purpose Developer Affiliation Distributor :PRZM : Pesticide Root Zone Model : predict concentrations of contaminants in ground waters : Carsel, R.F., Smith, C.N., Mulkey, L.A., Dean, J.D., Jowise, P. : U.S. EPA, ERL-Athens, GA : David Disney, CEAM : SARAH-2 : Surface Water Assessment Model : predict concentrations of contaminants in surface waters : Ambrose, R.B. and Vandergrift, S.B. : U.S. EPA, ERL-Athens, GA : David Disney, CEAM : SHAPE : Simulation of Human Activity and Pollutant Exposure : model distribution of population exposures to carbon monoxide : Ott, Wayne : U.S. EPA, ORD : Ott, Wayne, U.S. EPA, ORD :SWMM-4 : Storm Water Management Model : nonpoint source runoff from urban areas : Huber, W.C., Heaney, J.P., Nix, S.J., Dickinson, R.E., Polmann, D. : U.S. EPA, ERL-Cincinnati, OH : Tom Barnwell, U.S. EPA, ERL, Athens, GA : WASP-4 : Water Analysis Simulation Programs : predict concentrations of contaminants in surface waters : U.S. EPA, ERL-Athens, GA : David Disney, CEAM :WQA : Water Quality Assessment : predict cncntrtions of cntmnts in runoff, surface, and ground water : U.S. EPA, ERL-Athens, GA : David Disney, CEAM D-38 ------- Air Dispersion Models 1. Model Name Full Name Purpose Developer Affiliation Distributor 2. Model Name Full Name Purpose Developer Affiliation Distributor 3. Model Name Full Name Purpose Developer Affiliation Distributor 4. Model Name Full Name Purpose Developer Affiliation Distributor 5. Model Name Full Name Purpose Developer Affiliation Distributor 6. Model Name Full Name Purpose Developer Affiliation Distributor 7. Model Name Full Name Purpose Developer Affiliation Distributor : APRAC-3 : computes hourly average carbon monoxide concentrations : Simmon P.B., Patterson, R.M., Ludwig, F.L., Jones, L.B. :SRI : AREAL, NTIS :BLP : Buoyant Line and Point Source Dispersion Model : plume rise and downwash effects from stationary line sources : Schulman, L. L., and Scire, J. S. : Environmental Research and Technology, Inc. : AREAL, NTIS : CALINE-3 : California Line Source Dispersion Model : predict carbon monoxide concentrations near highways : Benson, P. E. : California Department of Transportation : AREAL, NTIS : CDM-2 : Climatological Dispersion Model-Version 2.0 : predict pollutant concentrations in rural or urban settings : Irwin, J. S., T. Chico, and J. Catalano : U.S. EPA, ASRL : AREAL, NTIS : CHEMDAT6 : estimate volatile organic compound emissions from TSDF processes :OAQPS :OAQPS : COMPLEX-1 : estimate concentrations of inert pollutants ; U.S. EPA, ASRL AREAL, NTIS : CRSTER : Single Source (CRSTER) Model : calculate concentrations from point source at polar coord, receptor : Monitoring and Data Analysis Division : U.S. EPA, OAQPS : AREAL, NTIS D-39 ------- 8. Model Name Full Name Purpose Developer Affiliation Distributor 9. Model Name Full Name Purpose Developer Affiliation Distributor 10. Model Name Full Name Purpose Developer Affiliation Distributor 11. Model Name Full Name Purpose Developer Affiliation Distributor 12. Model Name Full Name Purpose Developer Affiliation Distributor 13. Model Name Full Name Purpose Developer Affiliation Distributor 14. Model Name Full Name Purpose Developer Affiliation Distributor : HIWAY-2 : Highway Air Pollution Model : estimate concentration of non-reactive pollutants downwind of roads : Petersen, W.B. : US. EPA, ASRL : AREAL, NTIS : INPUFF : Multiple Source Gaussian Puff Dispersion Algorithm : estimate pollutant concentrations downwind of incinerator ships : Petersen, W.B., and Lavdas, L.G. : US. EPA, ASRL : AREAL, NTIS :ISC : Industrial Source Complex : assess pollutant concentrations associated w\ an industrial source : Environmental Protection Agency : US. EPA, OAQPS : AREAL, NTIS :LONGZ : calculate long term concentrations at receptors : Bjorklund, J.R., Bowers, J.F. : H.E. Cramer Co. : AREAL, NTIS : MESOPUFF-2 : Mesoscale PUFF Model : model the transport, diffusion and removal of air pollutants : Scire, J.S., Lurmann, F.W., Bass, A., and Hanna, S.R. : ERT, Inc. : AREAL, NTIS iMPTDS : Multiple Point Source Model With Deposition : estimate concentrations for inert pollutants : Rao, K.S., Satterfield, L. :ONRL : AREAL, NTIS :MPTER : Multiple Point Gaussian Dispersion Algorithm with Terrain Adjustmen : estimate concentrations for inert pollutants : Pierce, T.E., and Turner, D.B. : US. EPA, ASRL : AREAL, NTIS D-40 ------- 15. Model Name Full Name Purpose Developer Affiliation Distributor 16. Model Name Full Name Purpose Developer Affiliation Distributor 17. Model Name Full Name Purpose Developer Affiliation Distributor 18. Model Name Full Name Purpose Developer Affiliation Distributor 19. Model Name Full Name Purpose Developer Affiliation Distributor 20. Model Name Full Name Purpose Developer Affiliation Distributor 21. Model Name Full Name Purpose Developer Affiliation Distributor : PAL-2 : Point, Area, and Line Source Algorithm ; estimate short term concentrations of non-reactive pollutants ; Petersen, W.B., and Rumsey : U.S. EPA, ASRL : AREAL, NTIS :PBM : Photochemical Box Model : estimate ozone and other smog pollutants in an urban area : Schere, K.L., and Demerjian, K.L. : US. EPA, ASRL : AREAL, NTIS : PEM-2 : Pollution Episodic Model : predict short-term surface concentrations of two pollutants : Rao, K.S. : U.S. EPA, ASRL : AREAL, NTIS : PLUVUE-2 ; Plume Visibility Model II : predict transport and fate of point-source emissions : Seigneur, C, Johnson, G, Latimer, D., Bergstrom, R., Hogo, H. : SAI, Inc. : AREAL, NTIS PTPLU-2 estimate maximum surface concentrations Pierce, T.E., Turner, D.B., Catalano, J.A., Hale, F.V. HI U.S. EPA, ASRL AREAL, NTIS :RAM ; Gaussian-Plume Multiple Source Air Quality Algorithm : estimate concentrations of stable pollutants from urban sources : Catalano, J. A., D. B. Turner, and J. H. Novak : U.S. EPA, ASRL : AREAL, NTIS ROADWAY-2 predict pollutant concentrations near highways Eskridge, R.E., and Catalano, J.A. U.S. EPA, ASRL AREAL, NTIS D-41 ------- 22. Model Name Full Name Purpose Developer Affiliation Distributor 23. Model Name Full Name Purpose Developer Affiliation Distributor 24. Model Name Full Name Purpose Developer Affiliation Distributor 25. Model Name Full Name Purpose Developer Affiliation Distributor 26. Model Name Full Name Purpose Developer Affiliation Distributor 27. Model Name Full Name Purpose Developer Affiliation Distributor :RTDM : Rough Terrain Diffusion Model : estimate ground-level pollutant concentrations in rough terrain !ERT,Inc. :NTIS : SHORTZ : calculate short-term pollutant concentration : Bjorklund, J.R., Bowers, J.F. : H.E. Cramer Co. : AREAL, NTIS :TECJET : Advanced Jet Dispersion Model : modeling free jets of toxic and flammable substances : Technica International, Fullerton, CA : Technica International :TUPOS-2 : Multiple Source Gaussian Dispersion Algorithm Using On-Site Turbule : short-term impact assessment of inert pollutants : Turner, D.B., Chico, T., and Catalano, J.A. : US. EPA, ASRL : AREAL, NTIS :UAM : Urban Airshed Model : computing ozone concentrations in urban areas : Ames, J.S., Hayes, R., Myers, T.C., Whitney, D.C. : SAI, Inc. :NTIS : VALLEY • : estimate concentrations from point or area sources in complex terra : Burl, E.W. : US. EPA, OAQPS : AREAL, NTIS D-42 ------- Hazardous Waste Engineering Models l. Model Name Full Name Purpose Developer Affiliation Distributor 2. Model Name Full Name Purpose Developer Affiliation Distributor 3. Model Name Full Name Purpose Developer Affiliation Distributor 4. Model Name Full Name Purpose Developer Affiliation Distributor :EMBM : Energy-Mass Balance Model : simulation of industrial incineration : Lee, C.C U.S. EPA, Risk Reduction Engineering Laboratory, Cincinnati : Sonya Stelmack, U.S. EPA, RREL-Cincinnati CARDS : Geotechnical Analysis for Review of Dike Stability : evaluate earth dike structures at hazardous waste facilities U.S. EPA, Hazardous Waste ERL, Cincinnati, OH Landreth, Robert, U.S. EPA, HWERL, Cincinnati, OH :HELP : Hydrologic Evaluation of Landfill Performance Model : models the hydrologic effects at hazardous waste sites : Schroeder, P.R., Morgan, J.M., Walski, T.M., Gibson, A.C. : U.S. EPA, Hazardous Waste ERL, Cincinnati, OH ; Landreth, Robert, U.S. EPA, HWERL, Cincinnati, OH SOILINER Soil Liner Model simulation of liquid infiltration through compacted soil liner U.S. EPA, Hazardous Waste ERL, Cincinnati, OH Landreth, Robert, U.S. EPA, HWERL, Cincinnati, OH D-43 ------- Surface Water Model* 1. Model Name Full Name Purpose Developer Affiliation Distributor 2. Model Name Full Name Purpose Developer Affiliation 3. Model Name Full Name Purpose Developer Affiliation 4. Model Name Full Name Purpose Developer Affiliation Distributor 5. Model Name Full Name Purpose Developer Affiliation Distributor 6. Model Name Full Name Purpose Developer Affiliation Distributor 7. Model Name Full Name Purpose Developer Affiliation Distributor lACTMO : Agricultural Chemical Transport Model : nonpoint source model applicable to agricultural areas : Frere, M.H.; Onstad, C.A.; Holtan, H.W. : U.S. Dept. of Agriculture, Agricultural Research Service : Agriculture Research Service, U.S.D.A., Hyattsville, MD :AGRUN : Agricultural Watershed Runoff Model for the Iowa-Cedar River Basins : nonpoint source model applicable to agricultural watersheds : Roesner; Zison; Monser; Lyons : Water Resources Engineers, Inc. :ARM-2 : Agricultural Runoff Model : estimate pollutant loadings in agricultural areas ; Crawford, N.H., Donigian, A.S., Jr. : U.S. EPA, ERL-Athens, GA :CAFE : two dimensional hydrodynamics simulation in estuaries : Pagenkopf, J.R., Christodonlou, G.C., Pearce, B.R., Connor, J.J. ; Dept. of Civil Engineering, MIT, Cambridge, MA ; Pagenkopf, J.R., Dept. of Civil Eng., MIT, Cambride, MA :CHNHYD : Channel Hydrodynamic Model : simulating flows and water surface elevation in river networks ; Yeh, G.T. : Environmental Sciences Division, Oak Ridge National Laboratory, TN Yeh, G.T., ESD, Oak Ridge National Laboratory, TN rCHNTRN : Channel Transport Model : sediment & contaminant transport in rivers & well-mixed estuaries : Environmental Systems Division, Oak Ridge National Laboratory : Yeh, G.T., ESD, Oak Ridge National Laboratory : CREAMS : Chemicals, Runoff, and Erosion From Agricultural Management Systems : estimate pollutant loadings from agricultural areas : Knisel, W.G. : U.S. Dept. of Agriculture, Science and Education Administration : Walter Knisel, Southeast Watershed RL, U.S.D.A. D-44 ------- 8. Model Name Full Name Purpose Developer Affiliation Distributor 9. Model Name Full Name Purpose Developer Affiliation Distributor 10. Model Name Full Name Purpose Developer Affiliation Distributor 11. Model Name Full Name Purpose Developer Affiliation Distributor 12. Model Name Full Name Purpose Developer Affiliation Distributor 13. Model Name Full Name Purpose Developer Affiliation 14. Model Name Full Name Purpose Developer Affiliation :CTAP : Chemical Transport and Analysis Program : concentration distributions in water column & sediments i : HydroQual, Inc. : Gulledge, William, Chemical Manufacturers Association DWOPER Dynamic Wave Operational Model simulating river flow Fread, D.L. Hydrologic Research Laboratory, National Weather Service, NOAA Fread, D.L., NWS, NOAA, Silver Spring, MD iFETRA : transport of contaminants, sediments, in well-mixed estuaries ; Onishi, Y., Thomson, F.L. : Battelle, Pacific Northwest Laboratories : Onishi, Y., Battelle, Pacific Northwest Laboratories, WA :HEC-2 ; water surface profile in rivers for a steady flow discharge : Hydrologic Engineering Center : U.S. Army Corps of Engineers, Davis, CA : HEC, U.S. Army Corps of Engineers, Davis, CA :HEC-6 : profile water surface and stream bed : Hydrologic Engineering Center : U.S. Army Corps of Engineers, Davis, CA : HEC, U.S. Army Corps of Engineers, Davis, CA iMEXAMS : Metals Exposure Analysis Modeling System : fate and transport of metals in aquatic systems : Felmy, A.R., Brown, S.M., Onishi, Y., Argo, R.S., Yabusaki, S.B. : Battelle Pacific NW Lab : MICHRIV : transport in water & sediment in streams & nontidal rivers : DePinto, J.V., Richardson, W.L., Rygwelski, K. : U.S. EPA, ERL-Duluth D-45 ------- 15. Model Name Full Name Purpose Developer Affiliation 16. Model Name Full Name Purpose Developer Affiliation 17. Model Name Full Name Purpose Developer Affiliation Distributor 18. Model Name Full Name Purpose Developer Affiliation Distributor 19. Model Name Full Name Purpose Developer Affiliation Distributor 20. Model Name Full Name Purpose Developer Affiliation Distributor 21. Model Name Full Name Purpose Developer Affiliation Distributor :NPS : estimate nonpoint source pollutant loads in urban and rural areas : Donigian, A3., Jr., and Crawford, N.H. : U.S. EPA, ERL-Athens,GA :SEDONE : simulating hydrodynamic flow and sediment transport : Hetrick, D.M., Eraslan, A.H., Patterson, M.R. : Oak Ridge National Laboratory, TN ;SERATRA : Instream Sediment-Contaminant Transport Model : transport of contaminants & sediments in rivers : Onishi, Y., Wise, S.E. : Battelle, Pacific Northwest Laboratory for U.S. EPA : Onishi, Y., Battelle, Pacific Northwest Laboratory :SLSA : Simplified Lake/Stream Analyses : concentration distribution in water and sediments of rivers & lakes ; HydroQual, Inc. : Gullege, William, Chemical Manufacturers Association iTDMECS : Three-Dimensional Model for Estuaries and Coastal Seas : flow and contaminant transport in estuaries and coastal seas : Leendertse, J.J., Liu, S.K. : Rand Corporation, Santa Monica, CA : Liu, David, Rand Corporation, Santa Monica, CA : WATFLOW » : hydrodynamic flow in rivers and estuaries : Leendertse, J.J. : Rand Corporation, Santa Monica, CA ; Charles Sweeney, Engineering Hydraulics, Inc., Redmond, WA : WQSM ; Water Quality Simulation Model : flow and transport in well-mixed estuaries and costal seas : Leendertse, J.J. : Rand Corporation, Santa Monica, CA : Liu, David, Rand Corporation, Santa Monica, CA D-46 ------- Drinking Water Models 1. Model Name : PCAS Full Name : Packed Column Air Stripping Model Purpose : Developer : Cummins, M.D. Affiliation : U.S. EPA, Office of Drinking Water, Cincinnati, OH D-47 ------- |