Respondent operates a natural gas processing plant where raw natural gas is received via pipeline and processed to remove heavy natural gas liquids (NGLs) (i.e., butane, ethane, methane, pentane, propane, isobutane and isopentane ). After being processed and purified into a finished by-product, the NGL mixture is stored in pressurized tanks and transferred into tanker trucks for sale, while the clean natural gas is sold from the site via pipeline. During calendar year 2014, EPA opened an RMProgram compliance monitoring investigation to determine Respondent’s compliance with 40 C.F.R. Part 68 at its stationary source. As part of this investigation, the Respondent agreed to allow a duly authorized EPA representative to conduct an onsite inspection of its RMProgram related records and process equipment on August 7, 2014. The focus of the onsite inspection was to assess the Respondent’s compliance with RMProgram requirements for its covered processes operating at its stationary source.