Sec. 26.10.08.03. Release Investigation and Confirmation Steps

A. Unless corrective action is initiated in accordance with COMAR 26.10.09, owners, operators, and other responsible parties shall immediately investigate all suspected releases of regulated substances requiring reporting under Regulation .01 of this chapter within 48 hours or another time period specified by the Department, and shall comply with §§B and C of this regulation unless otherwise directed by the Department.

B. System Test. Owners and operators shall conduct tests, according to the requirements for tightness testing under COMAR 26.10.05.04D, that determine whether a leak exists in the tank or the piping, or both. When an UST system fails a test for tightness, the person in charge, owner, and operator shall take the following steps:

(1) Immediately discontinue use of the system and notify the Department;

(2) Within 48 hours, begin an investigation to determine whether the leak is occurring in the tank or piping system;

(3) If the tank is determined to be leaking, immediately remove the regulated substance;

(4) If the piping system is determined to be leaking, immediately drain and discontinue the use of the piping system;

(5) The storage system shall either be repaired or removed in accordance with COMAR 26.10.10; and

(6) After repairs have been made, and before its use, an UST system which has previously failed a test for tightness shall be tested by the precision test method to verify that the condition which caused the original failure of the test has been corrected.

C. Site Check.

(1) Owners, operators, and other responsible parties shall measure for the presence of a release where contamination is most likely to be present at the UST site. In selecting sample types, sample locations, and measurement methods, owners, operators, and other responsible parties shall consider the nature of the stored substance, the type of initial alarm or cause for suspicion, the type of backfill, the depth to ground water, and other factors appropriate for identifying the presence and source of the release.

(2) If the test results for the excavation zone or the UST site indicate that a release has occurred, owners, operators, and other responsible parties shall begin corrective action in accordance with COMAR 26.10.09.

(3) If the test results for the excavation zone or the UST site do not indicate that the release has occurred, the Department will determine if further investigation is required.

(4) Observation, monitoring, and recovery wells shall be constructed:

(a) In compliance with COMAR 26.04.04;

(b) Of polyvinylchloride;

(c) With a proper grout seal and locking cap; and

(d) As required in an approved corrective action plan.