40 CFR § 281.34 - Release reporting, investigation, and confirmation.
In order to be considered no less stringent than the corresponding federal requirements for release reporting, investigation, and confirmation, the state must have requirements that ensure all owners and operators conform with the following:
(a) Promptly investigate all suspected releases, including:
(1) When unusual operating conditions, release detection signals and environmental conditions at the site suggest a release of regulated substances may have occurred or the interstitial space may have been compromised; and
(2) When required by the implementing agency to determine the source of a release having an impact in the surrounding area; and
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