If the concentration of benzene, toluene, ethylbenzene, total xylenes, or MTBE is detected at equal to or greater than the levels of concern defined in Regulation .02B of this chapter in a groundwater sample collected and analyzed in accordance with Regulations .03—.05 of this chapter, an owner of a new or existing gasoline UST system shall: Within 24 hours of receiving an analytical laboratory report that shows the detection, report the sampling results to the Department; Within 48 hours of receiving an analytical laboratory report that shows the detection, initiate an investigation both on-site and off-site of the oil storage facility in accordance with COMAR 26.10.08.02—.04; and In accordance with COMAR 26.10.09.07, develop a corrective action plan under the direction of the Department.