Section 096-695-8 - Leak Detection MethodsA.All new and replacement underground hazardous substance storage facilities, including piping, must include a leak detection system operating between the inner and outer walls of the tanks and piping. In addition, pressurized piping systems must include a line leak detector that meets the requirements of Section 8C. B.All leak detection systems must meet the following requirements an a minimum: (1) All leak detection systems at all facilities must be capable of detecting a leak from any portion of the inner tank or piping;(2) All leak detection systems must be designed, installed, calibrated, operated, and maintained in accordance with the manufacturer's instructions and recommendations including routine maintenance and service checks for operability or running condition;(3) All leak detection systems must have a probability of leak detection of .95 or greater and a probability of false alarm of .05 or less;(4) A product tight and water tight non corrosive, product-compatible manway that provides visual access shall enclose any pump, leak detection, or ancillary equipment that contains product outside of the double wall tank or piping system; and(5) Monitoring methods for tracer substances or substances other than the specific hazardous substance or substances stored must be approved by the Department. NOTE: Electronic or manual, vapor or free product detection methods that meet the requirements of this section are acceptable.
C.Additional Leak Detection Requirements for Piping Systems(1) Suction pump piping systems must include a single check valve located immediately upstream from the pump such that a leak in any portion of the below ground piping will prevent the pump from operating properly thus alerting the owner or operator that a leak may be present.(2) Pressurized piping systems must include both a line leak detector capable of detecting a leak at 3 gallons per hour at 10 pounds per square inch line pressure within 5 minutes, and a continuous leak detection system in the interstitial space. Systems that combine line leak detection and interstitial space monitoring are acceptable. In addition, the line leak detector must incorporate one of the following: (a) An automatic shut off device;(b) A flow restriction device; or(c) An alarm that indicates a leak.(3) Line leak detectors shall be tested annually to be sure that they are operating properly. If a leak detector in not operating properly the facility shall cease operations until the leak detector is repaired or replaced.D.All written performance claims pertaining to any release detection system used at the facility, and the manner in which these claims have been justified or tested by the equipment manufacturer or installer, shall be maintained at the facility or at the owner or operators place of business and shall be made available to Department employees or local public safety officer upon request.06- 096 C.M.R. ch. 695, § 8