Release detection requirements for petroleum underground storage tank systems

Owners and operators of petroleum underground storage tank systems must provide release detection for tanks and piping as follows: 1. Tanks. Tanks must be monitored for releases as follows: a. Tanks installed on or before September 28, 2018, must be monitored for releases at least every thirty days using one of the methods listed in subsections 4 through 9 of section 33.1-24-08-33 except that: (1) Underground storage tank systems that meet the performance standards in section 33.1-24-08-10 or 33.1-24-08-11, and the monthly inventory control requirements in subsection 1 or 2 of section 33.1-24-08-33, may use tank tightness testing (conducted in accordance with subsection 3 of section 33.1-24-08-33) at least every five years until ten years after the tank was installed and tanks with capacity of five hundred fifty gallons [2081.98 liters] or less and tanks with a capacity of five hundred fifty-one to one thousand gallons which meet the tank diameter criteria in subsection 2 of section 33.1-24-08-33 may use manual tank gauging (conducted in accordance with subsection 2 of section 33.1-24-08-33). (2) Tanks installed after September 28, 2018, must be monitored for releases at least every thirty days in accordance with subsection 7 of section 33.1-24-08-33. 2. Piping. Underground piping that routinely contains regulated substances must be monitored for releases in a manner that meets one of the following requirements: a. Piping installed on or before September 28, 2018, must meet one of the following: (1) Pressurized piping. Underground piping that conveys regulated substances under pressure must: (a) Be equipped with an automatic line leak detector conducted in accordance with subsection 1 of section 33.1-24-08-34; and (b) Have an annual line tightness test conducted in accordance with subsection 2 of section 33.1-24-08-34 or have monthly monitoring conducted in accordance with subsection 3 of section 33.1-24-08-34. (2) Suction piping. Underground piping that conveys regulated substances under suction must either have a line tightness test conducted at least every three years and in accordance with subsection 2 of section 33.1-24-08-34, or use a monthly monitoring method conducted in accordance with subsection 3 of section 33.1-24-08-34. No release detection is required for suction piping that is designed and constructed to meet the following standards: (a) The below-grade piping operates at less than atmospheric pressure; (b) 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; (c) Only one 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 is provided that allows compliance with subparagraphs b through d to be readily determined. b. Piping installed or replaced after September 28, 2018, must meet one of the following: (1) Pressurized piping must be monitored for releases at least every thirty days in accordance with subsection 7 of section 33.1-24-08-33 and be equipped with an automatic line leak detector in accordance with subsection 1 of section 33.1-24-08-34; or (2) Suction piping must be monitored for releases at least every thirty days in accordance with subsection 7 of section 33.1-24-08-33. No release detection is required for suction piping that meets subparagraphs a through e of paragraph 2 of subdivision a of subsection 2.