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    Key Features

    Visual HELP Description

    Main Features of Visual HELP

    The Visual HELP Interface

    Creating a New Visual HELP Project

    Designing/Modifying a Model Profile

    WHI Weather Generator

    System Requirements

Key Features

• Simulate multiple landfill profiles to find the most suitable design
• Evaluate leachate mounding or leakage problems with current landfills
• Determine the effectiveness of landfill caps for reducing leachate mounding
• Design and optimize leachate collection systems

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Visual HELP Description

Visual HELP for Windows 95/98/NT is the most advanced hydrological modeling environment available for designing landfills, predicting leachate mounding and evaluating potential leachate seepage to the groundwater table. Visual HELP combines the latest version of the HELP model (v.3.07) with an easy-to use interface and powerful graphical features for designing the model and evaluating the modeling results. This latest version of the HELP model addresses many of the limitations and bugs from earlier versions, and also includes several new analysis features. Visual HELP uses the latest technologies in software engineering to introduce many new methods for visualizing and managing your projects, generating input data, presenting modeling results, and sharing data between models. The result is a powerful and easy-to-use modeling tool that makes hydrologic landfill modeling more practical and accessible than ever before! This completely-integrated modeling environment allows the user to: 1. Graphically create several profiles representing different parts of a landfill, 2. Automatically generate statistically reliable weather data for virtually any location in the world (or create your own), 3. Run complex model simulations, 4. Visualize full-color, high-resolution results, and 5. Prepare a summary document (tables and graphs) for your report For professional applications in landfill design, Visual HELP is the only software package you will ever need!

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Main Features of Visual HELP

• Easy-To-Use - The familiar design and functionality of the interface makes it extremely easy to learn and facilitates rapid model development using any of the available models.
• New Project Wizard - Creating a model is easy with a step-by-step wizard to guide you through the process (a model template is provided for to help get you started on your first project)
• Project Management - The project-based data management system liberates the user from handling of numerous files for separate projects
• Customizable Units - Choose from pre-defined unit templates or create your own unit template for all model parameters
• Input Data - The Project Tree allows you to quickly view and modify the profile data structure for each model profile, or to easily duplicate the model data files for performing multiple simulations for sensitivity analyses
• Model Profile View - The Profile View provides a graphical display of the geometry, dimensions, layer structure and stratigraphy of the model profile
• Database Links - A customizable database of soil parameters is linked to the various input forms for automatic entry of selected property values
• WHI Weather Generator - The built-in WHI Weather Generator generates up to 100 years of statistically reliable weather data to use as input
• Seamless Integration - Create the model profile(s), run the simulation(s), visualize the results, and create the report documents; all in the same graphical modeling environment
• Presentation of Results - Visual HELP comes with a powerful graphical component for visualizing the simulation results in graphical or tabular format
• Automatic Report Generator - Create a rich text document with tabulated input data, profile graphics, and a display of results, all with the click of a button
• Teamwork - Visual HELP supports teamwork environments so that project files can be run over a networked system
• Data Sharing - Export recharge data (infiltration rates) from Visual HELP to use as recharge boundary condition data in saturated zone groundwater models such as Visual MODFLOW
• Tutorials - Visual HELP comes with two step-by-step tutorials covering one example of modeling landfill hydrology and one example of estimating groundwater recharge at a site

The HELP model is a quasi-two-dimensional, deterministic, water-routing model for determining water balances. The following is a description of the HELP model as derived from the HELP program reference manual: The HELP program was developed by the U.S. Army Engineer Waterways Experiment Station (WES), Vicksburg, MS for the U.S. Environmental Protection Agency (EPA), Risk Reduction Engineering Laboratory, Cincinnati, OH, in response to needs in the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA, better known as Superfund) as identified by the EPA Office of Solid Waste, Washington, D.C. The primary purpose of the model is to assist in the comparison of landfill design alternatives as judged by their water balances. The Hydrologic Evaluation of Landfill Performance (HELP) model was developed to help hazardous waste landfill designers and regulators evaluate the hydrologic performance of proposed landfill designs. The model accepts weather, soil and design data and uses solution techniques that account for the effects of surface storage, snowmelt, runoff, infiltration, evapotranspiration, vegetative growth, soil moisture storage, lateral subsurface drainage, leachate recirculation, unsaturated vertical drainage, and leakage through soil, geomembrane or composite liners. Landfill system including various combinations of vegetation, cover soils, waste cells, lateral drain layers, low permeability barrier soils, and synthetic geomembrane liners may be modeled. Results are expressed as daily, monthly, annual and long-term average water budgets. The original version of the HELP model was first developed at WES in 1984 (Schroeder et al., 1984a and 1984b). Since then there have been many advances in the technology and scope of the model and many of the defects in the code have been corrected. The latest version of the HELP model is version 3.07 which contains many significant improvements and enhancements over the previous versions. The following is a brief outline of the enhancements that have been made since Version 2 of the HELP model (Schroeder et al., 1988a and 1988b).

• The number of layers that can be modeled has been increased
• The default soil material texture list has been expanded to contain additional waste materials, geomembranes, geosynthetic drainage nets and compacted soils
• The model now permits the use of customized soil textures
• Computations of leachate recirculation and groundwater drainage into the landfill have been added
• Leakage through the geomembranes due to manufacturing defects (pinholes) and installation mishaps (tears and punctures) is accounted for.
• Estimation of surface runoff has been improved to account for large landfill surface slopes and slope lengths
• The snow-melt model has been replaced with an energy-based model
• The Priestly-Taylor potential evapotranspiration model has been replaced with a Penman method that incorporates wind and humidity effects as well as long-wave radiation heat losses
• A frozen soil model has been added to improve infiltration and evapotranspiration predictions in cold regions
• The unsaturated vertical drainage model has also been improved to aid in storage computations

Visual HELP includes the latest version of the HELP model and Waterloo Hydrogeologic is currently working with the original developer of the HELP model (Dr. Paul Schroeder) to continue to develop and improve the HELP model to suit the advancing technology requirements of landfill engineers.

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The Visual HELP Interface

Visual HELP utilizes a very 'flat' interface structure and innovative graphical tools to give you convenient access to both the basic and advanced features of the HELP model. The result is a truly revolutionary approach to hydrological modeling that gives you more power and flexibility with your model profile than ever before. The interface is divided into three separate views, the Project Data Tree, the Profile View, and the Output View. When you open or create a project, you will be able to seamlessly switch between these views to build or modify the landfill design and model input parameters, run the simulations, and display results.

The Project Tree View displays the Visual HELP project you are working on, the names of each model profile, and each layer in the active model profile. The Project Tree View acts as a project manager allowing you to easily create and manage multiple model profiles within the same Visual HELP project. All model profiles for a project are saved in the same database for easy access and handling of the model data and simulation results. The Project Tree View also allows you to easily add layers, delete layers, edit layer properties and group multiple layers using standard Windows 95/NT right mouse button operations.

The Profile View provides a graphical representation of the landfill profile and allows you to graphically modify the layer geometry using standard 'point-and-click' and 'drag-and-drop' operations. The user can also add, delete, split or insert layers, or edit layer properties from the Profile View.

The Output View allows the user to display all of the generated weather data and modeling results using a comprehensive selection of graphical presentation formats. The display of data can be modified to choose daily, weekly, monthly or yearly results for the following simulated parameters:

• Precipitation, runoff and evapotranspiration
• Lateral drainage collected from selected model layers
• Percolation or leakance through selected model layers
• Average head accumulated on selected model layers

Each view of the Visual HELP interface can be seen from the main window as shown in the above figure.

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Creating a New Visual HELP Project

The logical structure of the Visual HELP interface facilitates a very quick learning curve that allows you to generate and modify a typical profile in just minutes. In many cases, the most difficult and time consuming task you will have is deciding what to name the project files. The following section provides a description of the steps involved in creating a hydrologic model profile using Visual HELP's advanced model generation tools. The following sections described the steps involved in creating a new Visual HELP project.

Each new Visual HELP project requires you to enter a unique project name, select the units (metric or english), and identify the author and the client for the project. A Project Description field also lets you enter a detailed description for tracking changes or for future references.

When you create a new model profile using either Visual HELP or SESOIL, you will be prompted to select a project location, including the longitude and latitude of the project location (approximate). The project location information is stored for general project description information and it is also used to locate the five nearest weather stations (you will be asked to select which weather station to use). The project database contains a list of locations from previous projects, or you can generate a new location.

If you choose to select a new location for the project, the following window will appear. If you know the Longitude and Latitude of the project location, you can enter it and add the new location to the database. Alternative, you can use the GIS component to graphically locate the project location (city). As shown in the figure below, you can select from a list of continental GIS maps to use when selecting the project location.

Once you select the appropriate GIS map, press the [Select Location ...] button to load the GIS map. In this example, we will use the US and Canada map to select a project location in California.

Zoom in to desired location....

Click the Cross-Hairs icon and then click on the desired location (Sacramento). The following popup window will appear listing the five nearest Meteo Stations.

Select the desired station and then press [OK]. The location description and coordinate information will automatically be completed as shown in the following screen capture.

If this information is correct, press the [Add] button to add this data to the list of project locations. This project location and weather station information will be used to help generate the weather data for either the Visual HELP model or the SESOIL model.

The next screen prompts you to select the Unit Template to apply for both the input parameters and the Output of modeling results. The Unit Template describes the unit settings for each parameter used in the model (e.g. length, time, permeability, flux rate, concentration, etc.). The default unit template is Customary (American units) but it can easily be changed to another pre-set unit template such as Metric, or to a model-specific unit template for SESOIL and VLEACH.

The Unit Template settings for each parameter can be viewed/edited by selecting the [Edit Units] button. Each parameter has a dropdown list containing a selection of different American and Metric units to choose from. Once you have selected the units for each parameter, you can save the new settings as a new Unit Template to use for a different project. You may easily create your own unit template customized to fit your input data requirements.

Once you have selected the desired Units for the project, press the [Next] button. The details for the new project will be displayed as shown in the following figure. If this information is correct, press the [Finish] button. Your new project will now be created and you will be transferred to the New Profile Wizard to guide you through the process of creating a model profile for the selected model.

The next window that appears will prompt you to choose whether you would want to create a new model profile using an existing model template, or by starting from a blank profile.

The existing profile template contains default settings for the case settings, number of layers, layer types, profile geometry, and material properties. The default settings can all be easily modified to suit your site conditions. Alternatively, if you choose to create a new profile you will be prompted for the required default settings for the profile. For this example, we will choose to use an existing profile template. Press the [Next] button to advance to the final screen of the New Project Wizard as shown in the figure below. This window provides a summary of the new profile details.

Press the [Finish] button to create a new Visual HELP model profile. Visual HELP will then create the Project Data Tree for the selected template model and a model profile will be displayed as shown in the figure below.

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Designing/Modifying a Model Profile

The Profile View provides a graphic representation of the model profile and allows you to graphically modify the layer geometry using standard drag-and-drop methods. The Profile View also allows you to add and delete layers, and view and edit the properties associated with each layer using the right mouse button. When you insert or delete a layer, you have the option of either fixing the top elevation or the bottom elevation of the profile.

In addition to being able to easily add, resize and delete layers, Visual HELP makes it simple to change the properties of different natural and artificial materials used in landfill design. Simply double-click on one of the layer materials listed in the Project Tree and the following window will appear. This window displays all of the properties of the selected layer.

Visual HELP provides you with the tools to group adjacent layers together and modify the function and/or common properties of these layers in a single operation. This is very convenient for assigning properties (e.g. 'slope') to groups of layers that serve a single purpose (such as a landfill cap).

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WHI Weather Generator

The WHI Weather Generator is used to create the atmospheric boundary condition data required by the Visual HELP model. The WHI Weather Generator is a built-in component for generating statistically reliable weather for virtually any location in the world for periods of up to 100 years. This powerful tool utilizes a database of more than 3000 international weather stations containing historical climatological data for each location. This database is fully customizable allowing the user to modify existing data or create new records to accommodate site specific weather conditions. Customized weather data can be entered manually, or imported from standard NOAA format. Note: The WHI Weather Generator utilizes the weather generation algorithm developed by the Agricultural Research Service of the U.S. Department of Agriculture (USDA). The WHI Weather Generator also includes the weather station database compiled by USDA containing statistically accurate summaries of the required climatological data for major weather stations located within the U.S.. The following section describes the steps required to generate weather data for your project location.

To generate the weather data for a Visual HELP or SESOIL model, simply click the Shining Sun icon on the upper menu bar to launch the WHI Weather Generator. Once the WHI Weather Generator is launched the following window will appear.

This window displays the project location, the selected Meteo Station for the project, and the simulation length. This window can be used to view and modify the default climatological settings for the project location. The Precipitation/Temperature tab can be used to view/modify the default settings for the monthly average precipitation and temperature values, while the Database tab can be used to view/modify all of the detailed climatological parameters. The weather data can be generated by clicking the Horse Icon . Once the weather data has been generated, you can display the simulated weather data (precipitation, radiation and temperature) using a built-in graphical component as shown below.

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System Requirements

• PC Pentium
• 32 Mb RAM
• 25Mb free disk space
• VGA display and mouse
• Windows 95/98/2000/NT

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