Total Petroleum Hydrocarbons (TPH)
Total Petroleum Hydrocarbons (TPH): The term “Total Petroleum Hydrocarbons” represents the complete carbon chain of hydrocarbon compounds that originate from petroleum. In general there are three ranges of TPH: Gasoline Range Total Petroleum Hydrocarbons (TPH-g); Diesel Range Total Petroleum Hydrocarbons (TPH-d); and Oil Range Total Petroleum Hydrocarbons (TPH-o). Gasoline range TPH represents the lighter end of the carbon chain, particularly from C-6 to C-12. Whereas oil range TPH represents the heavier end of the carbon chain, from C-29 to C-40. And in the middle, lies diesel range TPH, from roughly C-13 through C-28.
Soil & Groundwater Contamination of Total Petroleum Hydrocarbons+
During a Phase 1 Environmental Site Assessment, an environmental professional may identify a history of gasoline station underground storage tanks (USTs). The potential for leaking USTs is a “recognized environmental condition” per the ASTM E1527 standard. Thus, a recommendation for Phase 2 Environmental Site Assessment is in order. Soil contamination testing entails soil sample analysis via Environmental Protection Agency (EPA) Method 8015M, for the full Carbon Chain of Total Petroleum Hydrocarbons. And a professional geologist compares detections of each gasoline, diesel, and oil range hydrocarbon with the applicable screening level. For instance, Maximum Soil Screening Levels (MSLs).
