15A NCAC 02N .0904. PIPING

(a)  Piping, with the exception of flexible connectors and piping connections, shall be pre-fabricated with double-walled construction. Any flexible connectors or piping connections that do not have double-walled construction shall be installed in containment sumps that meet the requirements of 15A NCAC 02N .0905.

(b)  Piping must be constructed of non-corroding materials. Metal flexible connectors and piping connections shall be installed in containment sumps that meet the requirements of 15A NCAC 02N .0905.

(c)  Piping must comply with the UL 971 standard "Nonmetallic Underground Piping for Flammable Liquids;" that is in effect at the time the piping is installed.  UL 971 standard "Nonmetallic Underground Piping for Flammable Liquids" is hereby incorporated by reference including subsequent amendments and editions.  A copy may be obtained from Underwriters Laboratories, 333 Pfingsten Road, Northbrook, Illinois 60062-2096 at a cost of four hundred forty-five dollars ($445.00).

(d)  Piping that is buried underground must be constructed with a device or method that allows it to be located once it is installed.

(e)  Piping that conveys regulated substances under pressure must also be equipped with an automatic line leak detector that meets the requirements of 40 CFR 280.44(a).

(f) When existing piping is replaced or extended, the entire piping system shall meet the standards of this Section.  However, if only existing riser pipes, flexible connectors, fittings, flanges, valves or pumps are replaced, then only the replacement equipment must meet the standards of this Section.

(g)  At the time of installation, the primary containment and interstitial space of the piping shall be initially tested, monitored during construction and finally tested in accordance with the manufacturers written guidelines and PEI/RP100, "Recommended Practice for Installation of Underground Liquid Storage Systems." The presence of soap bubbles or water droplets or any loss of pressure beyond the limits specified by the piping manufacturer during testing shall be considered a failure of the integrity of the piping. If the piping fails a tightness test, it must be replaced or repaired by the manufacturer or the manufacturer's authorized representative in accordance with the manufacturer's written specifications. Following any repair, the piping must be re-tested for tightness in accordance with the manufacturers written guidelines and PEI/RP100, "Recommended Practice for Installation of Underground Liquid Storage Systems."

(h)  Piping that is not monitored continuously for releases using vacuum, pressure or hydrostatic methods, must be tested for tightness every three years following installation. The primary containment and interstitial space of the piping shall be tested in accordance with the manufacturers written guidelines and PEI/RP100 "Recommended Practice for Installation of Underground Liquid Storage Systems." If the piping fails a tightness test, it must be replaced or repaired by the manufacturer or the manufacturer's authorized representative in accordance with the manufacturer's specifications. Following any repair, the piping must be re-tested for tightness. The most recent periodic tightness test record must be maintained at the UST site or the tank owner or operator's place of business and must be readily available for inspection.

 

History Note:        Authority G.S. 143-215.3(A)(15); 143B-282(A)(2)(H);

Eff. November 1, 2007.