Underground Storage Tanks (UST) NJ UST Investigation Sites

NJDEP Permit Requirements for Nonmetallic Underground Piping
(posted 2 Dec 2005)

• New and revised requirements to UL 971 for nonmetallic underground piping for flammable liquids were developed and issued on January 2, 2004, for compliance by July 2004 (product marking and instructions) and July 2005 (performance requirements).
• The scope of UL 971 was revised to clearly indicate that piping systems evaluated to the standard are intended only for underground applications. Excluded were uses in sump, above ground and marine applications. Separate requirements are currently being developed for the excluded applications.
• In addition to evaluating the piping system for normal use (long-term exposure of primary interior to fuel and exterior to soil, short-term exposure of the secondary interior to fuel and long-term exposure to soil) abnormal use conditions were also added, i.e.; long-term exposure to primary exterior and secondary interior to fuel. Physical test were also revised to better simulate abnormal abuses expected during assembly and installation, such as over torque and over bend conditions, drops, impacts, pull, crush and puncture.
• To reduce the potential for unqualified contractors installing underground fuel piping systems, UL added requirements for manufacturers to have a system in place to qualify persons that assemble and install their products as well as provide training and assistance. In addition, manufacturers are to provide their recommended instructions for assembly and installation with products.
• Instead of concentration tests on individual materials or components, as in previous editions of the Standard, the new and revised requirements focus on evaluation of pipe and fittings as a completed system when connected in accordance with the manufacturers' instructions. This was required for both short and long-term test whenever possible; recognizing that the system is always limited by the weakest part.
• Because piping systems should be expected to withstand long-term exposures after expected physical abuses during assembly and installation, pre-conditioning of samples was introduced prior to compatibility and permeation tests. The pre-conditioning consists of bending to the manufacturers' minimum radius and conducting drop and impact tests at levels that are not considered visible damage to the qualified person.
• Revised requirements after long-term exposure to fluids (soils and fuels); new requirements or materials stability (maximum 2% length and diameter dimensional change, maximum 5% weight change); plus evaluation of systems (pressure, pull, crush) were introduced and minimum retention values were increased (80% for primary, 70% for secondary). The test time for secondary systems was also increased to that of the primary systems.
• Minimum allowable permeation limits were reduced (4g/sqm/day to 1 g/sqm/day for primary and 24 g/sqm/day to 4 g/sqm/day for secondary with test times for secondary systems increased to 180-days. The test was also conducted on systems to evaluate the pipes to fitting connections.

The new and revised requirements to UL 971 will enhance the safety performance of the products; however, a performance-based Standard cannot address all the factors associated with their proper use. Therefore, as of July 1, 2005: In accordance with the New Jersey Department of Environmental Protection's (Department) regulations, the installation of nonmetallic underground piping for flammable liquids that does not meet the new and revised UL 971 Standard without appropriate permit is prohibited.

The application for such a permit must demonstrate that the nonmetallic piping construction and corrosion protection prevents the release or threatened release of any stored regulated substance in a manner no less protective than the UL 971 Standard effective as of July 1, 2005.

The basis for this prohibition is N.J.A.C. 7:14B, the Department's rules promulgated pursuant to N.J.S.A. 58:10A-21 et seq. Specifically, N.J.A.C. 7:14B-4.1(a)2iv, and N.J.A.C. 7:14B-4.1(h)1. Please review these rules for further clarification.

Questions concerning the above should be addressed to Greg Cunningham at (609) 292-2769 or via e-mail to greg.cunningham@dep.state.nj.us.