Anonymous public comment

Dear EPA, As a soil chemistry researcher working in the area of oil-based drilling mud, it would be very helpful if the the ASTM D7066 and D7575 were approved as alternatives to EPA 1664. The D7066 method is a suitable alternative in regard to TPH and is much easier, faster, and cheaper than a GC method. Such an approval would allow us to conduct MUCH more research on the impact of oil-based drilling mud on soil quality and environmental risk. Please consider that the D7066 method is a well established infra-red method based on EPA 413.2 and 418.1 methods, but utilizes a non ozone depleting substance during extraction. Thank you for your time.