Modeling Subsurface Petroleum Hydrocarbon Transport

What was new a while ago....

5-22-2005 Estimates of chemical properties for petroleum hydrocarbons and oxygenated additives have been developed using the SPARC Performs Automated Reasoning in Chemistry (SPARC) calculator. These results were used in evaluating the potential environmental impacts from gasoline in the U.S. This data set can be searched for chemicals of interest at temperatures relevant for shallow ground water (5 ^oC to 25 ^oC).
3-20-2005 The diffusion coefficient estimator has been split into two parts. The first contains predefined input data for petroleum hydrocarbons and oxygenated additives. The second allows input of all parameters and can serve a wider range of chemicals.
2-14-2005 More datapoints can be entered into the gradient calculator and the coefficient of determination (R²) has been added to the output.

5-26-2004 A forward calculation version of the Johnson-Ettinger model has been added
5-15-2004 An on-line version of the Johnson-Ettinger model for intrusion of contaminated vapors into residential buildings has been developed. The on-line implementation provides a simplified uncertainty analysis and automated execution of the model. Background on the model is provided on separate web pages and an explanation between different EPA versions of the model are given.
4-30-2004 The temperature-dependent Henry's Law Calculator has been updated to include data from EPA's Office of Solid Waste and Emergency Response(OSWER). This change greatly expands the number of chemicals included in the calculator, and gives provides an automated way of accessing the OSWER data and methods.

2-25-2004 Two modules have been added to the Modeling Subsurface Transport of Petroleum Hydrocarbons course: Introduction to fate and transport and phase distribution of water-immiscible liquids. These are the first two modules that are available for usage. Information on how to use the materials is provided.

12-15-2003 Approximation of temperature-dependent effective solubilities has been added to OnSite. Along with background data and a Fahrenheit to Celsius calculator.
12-15-2003 Temperature dependence in the Henry's Law Constant for methyl tert-butyl ether (MTBE) has been added to the Henry's Law Coefficient Estimator

6-30-2003 Estimation of vertical gradients has been added to the on-line calculators
6-30-2003 A page on chemical property estimation has been added the Ecosystems Research site
- 4-30-2003 A calculator was added to estimate of Air- and Water-Phase diffusion coefficients
- 4-30-2003 The mass distribution calculator has been enhanced to generate concentrations in all phases and the relationship between the effective solubility calculator has been made clearer.
- 4-30-2003 Uncertainty in transport model calculations can be assessed for a one-dimensional model. A paper describing the model results, also defines bounding parameter estimates for various outputs of the model.
- 4-30-2003 A listserver has been established to keep up with information concerning OnSite and the web course.
- 9-24-2002 The Retardation Factor and 1D Transport from a Pulse Source calculators have been enhanced to include organic carbon partition coefficients compiled by EPA or certain State environmental programs. Contact Jim Weaver with requests for additional chemicals or data sets.
- 9-24-2002 A gradient calculator has been added to determine gradients from up to 10 wells.
- 9-19-2002 Corrections to the three point-gradient calculator
- 11-1-2001 New Lat-Long to distance calculators for degrees-minutes-seconds or decimal degrees
- 11-1-2001 Three point gradient calculator with out map scaling
- 11-1-2001 Reorganization of calculator list
- 6-27-2001 Addition of an environmental careers web site
- 04-25-2001 Error preventing calculation in the half life / rate constant converter corrected.
- 01-22-2001 New web address for the Web Course and Onsite:
  - WebCourse --- https://www.epa.gov/athens/learn2model
  - OnSite --- https://www.epa.gov/athens/onsite
- 02-27-2001 Revision of the One-Dimensional Continuing and Pulse Source Calculator. The calculator now calculates the first arrival time for a specified concentration and is intended to replace the travel time calculation previously performed in the seepage velocity calculator
- 02-27-2001 Replacement of the seepage velocity calculator
- 02-27-2001 Inclusion of tenths of inches in the gradient calculators.
- 02-27-2001 Correction of graphics problems throughout the site
- 02-09-2001 Complete removal of data storage in cookies
- 02-09-2001 New calculators:
- - Averaging of borehole concentrations
  - Three dimensional "Domenico Models:
    Steady-state, centerline model
    Unsteady model
- 01-22-2001 New Category of calculators: scientific demonstrations
- - water flow through a one-dimensional column
  - 02-09-2001 flow in a one-dimensional aquifer
  - 02-09-2001 unsteady mass balance
- 01-22-2001 Corrections to the seepage velocity and gradient scaled from a map calculators. Corrections:
- - gradient calculation with y coordinates in seepage velocity calculator
  - gradient calculation with fractional portion of measurement units in gradient scaled from a map calculator
- Printer friendly page equivalents for each graphics and text only page
- October 5, 2000 Text only parallel site (subsequently disabled because of new EPA design: capability exists otherwise)
- October 5, 2000 New example site assessment with the OnSite calculators
- July 18, 2000 Steady State Plume Length Calculator
- 7-10-2000 Removal of data storage in OnSite.
- 6-19-2000 A new plume diving calculator and documentation. Unlike the rest of OnSite the plume diving calculator is implemented as a JAVA applet: therefore its download time may be longer than for the other calculator pages.
- 6-19-2000 Revision of the seepage velocity and one-dimensional pulse source model to allow for user entry of the organic carbon partition coefficient K_oc.
- 5-1-2000 New module showing pictures of field sampling and equipment.
- 5-1-2000 New calculator for estimating Henry's Law Constants as a function of temperature.
- 5-1-2000 New calculator for determining the gradient and direction from three points.
- 5-1-2000 Revision of JavaScript Cookies for OnSITE calculators.
- 5-1-2000 Expanded example of calculator usage including a review of fate and transport.
- 5-1-2000 Revision of gradient calculators to eliminate unnecessary inputs.
- 10-11-1999 Control of significant digits and use of scientific notation where needed in all calculators
- 10-11-1999 Calculation of the gradient scaled from a map and unit conversion for flow rates
- 9-13-1999 Calculators for the gradient, moisture content and leaching from a NAPL source
- 5-19-1999 A calculator for calculating the effective solubility of BTEX and MTBE from petroleum fuels.
- 5-14-1999 Try out the calculators for
  - Transport related formulas
  - - Ground water flow
    - Retardation constants
    - Half lives and rate constants
    - Seepage velocity and travel times
    - Effective solubility
  - Unit conversions
  - - Henry's Law
    - Hydraulic conductivity
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Contact Jim Weaver to ask a technical question on this material.