Owners and operators of aboveground storage tank (AST) and underground storage tank (UST) systems must report to the agency within 24 hours (see §334.50(d)(9)(A)(v) of this title (relating to Release Detection) for reporting requirements associated with statistical inventory reconciliation inconclusive results), and follow the procedures in §334.74 of this title (relating to Release Investigation and Confirmation Steps) for any of the following conditions:
  (1) The discovery by owners and operators, or written notification by others to the owner or operator, of released regulated substances at the AST or UST site or in the surrounding area (such as the presence of non-aqueous phase liquids or vapors in soils, basements, sewer and utility lines, and nearby surface water).
  (2) Unusual operating conditions observed by owners or operators (such as the erratic behavior of product dispensing equipment that is consistent with or indicates a release, the sudden loss of product from the AST or UST system, an unexplained presence of water in the tank, or liquid in the interstitial space of secondarily contained systems), unless:
    (A) the system equipment or component is found not to be releasing regulated substances to the environment;
    (B) any defective system equipment or component is immediately repaired or replaced; and
    (C) for secondarily contained systems, except as provided for in §334.50(d)(8)(C) of this title, any liquid in the interstitial space not used as part of the interstitial monitoring method (for example, brine filled) is immediately removed.
  (3) Monitoring results, including investigation of an alarm, from a release detection method required under §334.50 of this title or other method that indicates a release may have occurred unless:
    (A) the monitoring device is found to be defective and is immediately repaired, recalibrated, or replaced, or the monitoring procedure is found to be ineffective, and is modified, and additional monitoring does not confirm the initial result;
    (B) in the case of inventory control, described in §334.50(d)(1)(B) of this title, a second 30-day period of data does not confirm the initial result or the alarm investigation determines no release has occurred;
    (C) the leak is contained in the secondary containment:
      (i) except as provided for in §334.50(d)(8)(C) of this title, any liquid in the interstitial space not used as part of the interstitial monitoring method (for example, brine filled) is immediately removed; and
      (ii) any defective system equipment or component is immediately repaired or replaced; or
    (D) the alarm was investigated and determined to be a non-release event (for example, from a power surge or caused by filling the tank during release detection testing).

Source Note: The provisions of this §334.72 adopted to be effective September 29, 1989, 14 TexReg 4714; amended to be effective November 23, 2000, 25 TexReg 11442; amended to be effective May 31, 2018, 43 TexReg 3390