Sec. 26.10.05.02. Requirements for Petroleum UST Systems

A. Owners and operators of petroleum UST systems shall provide release detection for tanks and piping as described in this regulation.

B. Tanks. All UST systems shall be inventoried daily as described in COMAR 26.10.04.01E-G. In addition, UST systems shall be monitored at least every 30 days for releases using one of the methods listed in Regulation .04B-I of this chapter.

C. Exceptions. The following constitute exceptions to the requirements in §B of this regulation:

(1) UST systems that meet the performance standards in COMAR 26.10.03.01 and .02, and the daily inventory control requirements in COMAR 26.10.04.01E-G, may use precision tightness testing, in accordance with Regulation .04D of this chapter, at least every 5 years until December 22, 1998;

(2) UST systems that do not meet the performance standards in COMAR 26.10.03.01 or .02 may use daily inventory controls, in accordance with COMAR 26.10.04.01E-G, and annual precision tightness testing in accordance with Regulation .04D of this chapter, until December 22, 1998, when these systems shall be upgraded under COMAR 26.10.03.08 or permanently closed under COMAR 26.10.10; and

(3) Tanks with a capacity of 550 gallons or less and not metered may use weekly manual tank gauging, conducted in accordance with Regulation .04C of this chapter.

D. Piping.

(1) Underground piping that routinely contains regulated substances shall be monitored for releases in a manner that meets one of the requirements of this section.

(2) Pressurized Piping. Underground piping that conveys regulated substances under pressure:

(a) Shall be equipped with an automatic line leak detector which is tested annually and which will:

(i) Alert the operator to the presence of a leak by restricting or shutting off the flow of a regulated substance through piping or triggering an alarm; and

(ii) Detect a release of a regulated substance of at least 3 gallons per hour at 10 pounds per square inch line pressure within 1 hour; and

(b) Shall:

(i) Be tested for tightness annually, with a precision test that detects a 0.10 gallon per hour release at 1.5 times the operating pressure, and the test shall be performed for at least 1 hour; or

(ii) Be monitored monthly in accordance with Regulation .04F-I of this chapter.

(3) Suction Piping. Underground piping that conveys regulated substances under suction shall be tested for tightness at least every 2 years with a precision test performed for 1 hour at a pressure between 5 and 15 pounds per square inch that detects a 0.1 gallon per hour release, or be monitored monthly in accordance with Regulation .04F-I of this chapter. Release detection and precision testing are not required for suction piping when:

(a) The piping operates at less than atmospheric pressure;

(b) The piping is sloped so that the contents of the pipe will drain back into the storage tank if the suction is released;

(c) A single check valve is included in each suction line;

(d) The check valve is located directly below and as close as practical to the suction pump; and

(e) A method for visual inspection to determine compliance is provided.

(4) Secondary containment piping shall be tested:

(a) For new, upgraded, or replaced piping before operation of the UST system and completion of the underground oil storage facility; and

(b) Every 5 years thereafter.