ENV-99-177 Evaluating Remediation Needs and Options – A Fraction-Specific Approach to Soil and Groundwater 'TPH' Analysis

Description:

Historic petroleum releases have led to the widespread occurrence of contaminated soil and groundwater at refining and distribution facilities. Because of the complex chemical nature of crude petroleum and its distillates, and the changes which it undergoes after its release into the environment, the need to remediate the total petroleum hydrocarbon (TPH) impacted soil or groundwater is largely dependent upon (1) a wide variety of regulatory requirements (action levels and clean-up criteria) and (2) the analytical method(s) used to determine TPH concentrations. Recent advances in the measurement of TPH have employed methods which, instead of characterizing the ‘total’ hydrocarbons, determines the character, concentration, and potential toxicity of specific boiling range (carbon range) fractions within the petroleum assemblage. The benefit of this approach lies in the ability to better determine the environmental and human health risk posed by the contamination. Comparison of the risk to acceptable regulatory levels, in turn, can be used to determine the need for, or goal of, the remediation. In this paper, an analytical method for the analysis of Fraction Specific Hydrocarbon (FSH) contamination in environmental samples is described. The method utilizes a combination of existing U.S. EPA Methods (3630, 8260, 8270 and/or 8015) while adopting the guidance of the Total Petroleum Hydrocarbon Criteria Working Group (TPHCWG) and Texas Natural Resources Conservation Committee (TNRCC) methods for fraction-specific hydrocarbon analysis.