An owner and an operator of a storage tank system, a responsible party, and a person conducting a test on a storage tank system shall report to the Department a suspected spill, release, or discharge immediately, but not later than 2 hours after the discovery, and follow the investigation and confirmation procedures in Regulation .03 of this chapter if any of the following circumstances occur: There is evidence of a spill, release, or discharge of oil; There is evidence of a spill, release, or discharge of a regulated substance from a UST system; A storage tank system fails a precision tightness test; A storage tank system has two consecutive inconclusive precision tightness test results; A storage tank system is determined to have a leak or there is evidence of a spill, release, or discharge of oil at an oil storage facility or oil handling facility, such as the presence of: Dissolved product in groundwater; Absorbed product in soils; Free product in soils, a basement, a sewer or utility line, or waters of the State; or Vapors in soils, a basement, a sewer or utility line, or waters of the State; There is evidence of a spill, release, or discharge at a regulated substance storage facility or in the surrounding area, such as the presence of: Dissolved product in groundwater; Absorbed product in soils; Free product in soils, a basement, a sewer or utility line, or waters of the State; or Vapors in soils, a basement, a sewer or utility line, or waters of the State; Unusual operating conditions exist, such as: The erratic behavior of product-dispensing equipment; The sudden loss of a regulated substance from a storage tank system; An unexplained presence of water in a storage tank; Liquid in the interstice space of secondarily contained systems; or A failed spill prevention equipment or containment sump test for tightness; and Monitoring results, including investigation of an alarm, from a release detection method required under COMAR 26.10.05 indicate a spill, release, or discharge may have occurred, unless: The monitoring device is found to be defective and immediately repaired, recalibrated or replaced; and Additional monitoring does not confirm the initial result. Additional Reporting Circumstances. For the purposes of this section, evidence of a spill, release, or discharge include: The visual detection of free product; or An analytical laboratory report that shows a detection of a petroleum constituent in a soil, groundwater, drinking water, or soil vapor sample at a concentration equal to or exceeding a cleanup standard or action level published by the Department for the petroleum constituent and media type. If evidence of a spill, release, or discharge is discovered during an environmental assessment conducted on a property as part of a due diligence investigation in support of a property transaction or a loan refinancing, the person conducting the environmental assessment and the owner of the property shall report the suspected spill, release, or discharge to the Department: Immediately, but not later than 2 hours after the visual detection of free product; or Within 48 hours of receiving an analytical laboratory report described under §B(1) of this regulation. The person performing an environmental assessment on a property or the owner of the property may not be considered a person responsible for the discharge solely as a result of discovering evidence of a spill, release, or discharge or reporting a suspected spill, release, or discharge to the Department in compliance with §B(1) of this regulation, unless the person performing the environmental assessment or the property owner meets the criteria for a person responsible for the discharge under COMAR 26.10.01.02B.