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Volume Determination and Recoverability of Free Hydrocarbon
Author(s) -
Testa Stephen M.,
Paczkowski Michael T.
Publication year - 1989
Publication title -
groundwater monitoring and remediation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.677
H-Index - 47
eISSN - 1745-6592
pISSN - 1069-3629
DOI - 10.1111/j.1745-6592.1989.tb01127.x
Subject(s) - environmental remediation , petroleum engineering , extrapolation , hydrocarbon , environmental science , volume (thermodynamics) , computer science , process engineering , geology , engineering , statistics , mathematics , chemistry , ecology , physics , organic chemistry , quantum mechanics , contamination , biology
Free‐phase hydrocarbon product occurs as perched zones on the capillary fringe beneath numerous petroleum‐handling facilities. Under such site conditions, too much emphasis is placed on the time‐frame required for remediation by federal, state, and local regulators, notably in respect to monitoring the efficiency and effectiveness of the respective remediation program. The time required for remediation within the scope of present‐day technology is a calculated or educated guess at best. Typically, remediation duration is determined by a number of estimates. These estimates have innate compounding errors. Areas of estimation include physical measurement accuracy; “true” vs. apparent thickness; validity of bail‐down testing; extrapolation of free hydrocarbon product thicknesses between monitoring points; contouring of thickness maps, extrapolation of geologic information, planimetering, and estimation of porosity; specific yield and retention; all of which are key factors used in ultimately determining the volume of free hydrocarbon product in place. Once an initial estimated volume is determined, pilot testing of a recovery system should commence to determine recovery rates. Factors that will affect recovery rates include the areal distribution and geometry of the hydrocarbon pool, type, and number of recovery system(s) selected, and the performance or efficiency of these systems with time. Effectiveness of the recovery program is thus best estimated based on barrels recovered to date divided by the total volume of barrels that are considered recoverable. Remediation time frame at petroleum hydrocarbon recovery sites can be estimated. However, regulators at all levels need to be aware of the large number of compounding errors associated with these calculations. Estimations should be used with extreme caution, because they are usually overestimations. Once a realistic time frame for remediation is mutually agreed upon, it should be clearly understood that it is flexible. It is recommended that a range be initially determined and that as a project progresses and new data are introduced, the remediation time frame be adjusted accordingly.