280.41—Requirements for petroleum UST systems.

Owners and operators of petroleum UST systems must provide release detection for tanks and piping as follows:
(a) Tanks. Tanks must be monitored at least every 30 days for releases using one of the methods listed in § 280.43 (d) through (h) except that:
(1) UST systems that meet the performance standards in § 280.20 or § 280.21, and the monthly inventory control requirements in § 280.43 (a) or (b), may use tank tightness testing (conducted in accordance with § 280.43(c)) at least every 5 years until December 22, 1998, or until 10 years after the tank is installed or upgraded under § 280.21(b), whichever is later;
(2) UST systems that do not meet the performance standards in § 280.20 or § 280.21 may use monthly inventory controls (conducted in accordance with § 280.43(a) or (b)) and annual tank tightness testing (conducted in accordance with § 280.43(c)) until December 22, 1998 when the tank must be upgraded under § 280.21 or permanently closed under § 280.71; and
(3) Tanks with capacity of 550 gallons or less may use weekly tank gauging (conducted in accordance with § 280.43(b) ).
(b) Piping. Underground piping that routinely contains regulated substances must be monitored for releases in a manner that meets one of the following requirements:
(1) Pressurized piping. Underground piping that conveys regulated substances under pressure must:
(i) Be equipped with an automatic line leak detector conducted in accordance with § 280.44(a); and
(ii) Have an annual line tightness test conducted in accordance with § 280.44(b) or have monthly monitoring conducted in accordance with § 280.44(c).
(2) Suction piping. Underground piping that conveys regulated substances under suction must either have a line tightness test conducted at least every 3 years and in accordance with § 280.44(b), or use a monthly monitoring method conduct in accordance with § 280.44(c). No release detection is required for suction piping that is designed and constructed to meet the following standards:
(i) The below-grade piping operates at less than atmospheric pressure;
(ii) The below-grade piping is sloped so that the contents of the pipe will drain back into the storage tank if the suction is released;
(iii) Only one check valve is included in each suction line;
(iv) The check valve is located directly below and as close as practical to the suction pump; and
(v) A method is provided that allows compliance with paragraphs (b)(2) (ii)-(iv) of this section to be readily determined.