Respondent owned a soil vapor extraction system and associated thermal oxidizer at the W.G. Krummrich Plant. ON July 20,2012 at or about 9:00 a.m. the thermal oxidizer shut down, but the soil vapor extraction system continued operating. This initiated a release of approximately 135 pounds of benzene into the ambient air. The release occurred over approximately 74 hours until it was discovered and manually stopped on July 23, 2012. Respondent notified the NRC of the release on July 26, 2012 at 1:23 p.m . Respondent did not immediately notify the NRC as soon as the Respondent had knowledge of the release. Respondent did not immediately notify the Illinois SERC as soon as Respondent had knowledge. Respondent did not notify the LEPC immediately and it is a violation of Section 304. Please see CAFO for full explanation. CERCLA civil penalty was $6,640 and civil penalty for EPCRA violations was $13,280. In addition Respondent must complete a supplemental environmental project of at least $74,778 to purchase equipment for the St. Clair Special Emergency Services Association.