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Underground Storage Tanks (USTs)

UST Technical Compendium: Release Investigation, Confirmation, and Corrective Action

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  • Question 1: Are typical response actions of the utility industry to various types of confirmed releases from underground emergency generator tanks at nuclear power stations in conformance with the final UST corrective action regulatory requirements of 40 CFR 280.61(b) and 280.62(a)(1)?
    [February 21, 1989 letter from Garah Helms of the Utility Solid Waste Activities Group, Edison Electric Institute]
    Answer: When a release from an emergency generator tank is confirmed, the nuclear facility's owner and operator must begin to take immediate action to prevent further releases, including action that leads to the removal of as much of the regulated substance from the UST system as necessary.
    [April 4, 1989 Letter to Mr. Helms (PDF) (10 pp, 361 K)]
  • Question 2: Does EPA require tank removal when a tank fails a tightness test?  Is our company's site investigation checklist adequate?
    [August 21, 1989 letter from R.C. Cronau of R.C. Cronau and Associates, Inc.]
    Answer: Section 280.52 (a)(1) specifies that when a second tightness test is used to confirm a suspected release, the UST owner must "repair, replace, or upgrade the UST system and begin corrective action" if the system is non-tight. Thus, repair and upgrading is also allowed by EPA, in addition to tank removal. However, the actual approach followed is dependent on site conditions and the implementing agency's decision as to whether the initial abatement actions, site check activities, and corrective action measures necessitate tank removal. The submitted checklist is generally accurate, as far as it goes, for overfill type testing. It is not complete and does not incorporate level measuring or acoustic methods, and does not acknowledge the site check alternative mentioned in the regulations.
    [December 1, 1989 Letter to Mr. Cronau (PDF) (10 pp, 361 K)]
  • Question 3: Is a constituent required to remove contaminated soil that is a result of a spill from over 40 years ago, if this contamination is discovered while recently installing a new tank?
    [May 1991 letter from Senator Helms]
    Answer: It is basically the state's decision as to whether the soil in the area of the old release must be removed. Continue to openly discuss this evolving situation with those responsible state officials, including whether this is already a leak from the operating USTs that must be addressed.
    [Undated Letter to Senator Jesse Helms (PDF) (10 pp, 361 K)]
  • Question 4: Do old releases have to be reported?
    Answer: Yes, owners and operators of USTs subject to the final rules must report both suspected and confirmed releases (see 40 CFR Part 280.50-3). There is no regulatory distinction between old or new releases, and it is technically difficult, if not impossible, to determine the age of a release. The implementing agency can require proper closure (including site assessment) and corrective action at old sites suspected of having a release.
    [There is no additional material included for this answer]
  • Question 5: Could EPA please clarify its final regulations for reporting releases from underground storage tanks?
    [December 22, 1988 letter from Gregory P. Underwood]
    Answer: Under the new regulations, any leak that is discovered must be reported immediately to the implementing agency and action undertaken by the owner and operator to stop additional releases.
    [February 27, 1989 letter to Mr. Underwood (PDF) (10 pp, 361 K)]

All references cited by the questions and answers above can be found together in the following resource:

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