Code of Maine Rules
06 - DEPARTMENT OF ENVIRONMENTAL PROTECTION
096 - DEPARTMENT OF ENVIRONMENTAL PROTECTION - GENERAL
Chapter 695 - RULES FOR UNDERGROUND HAZARDOUS SUBSTANCE STORAGE FACILITIES
Appendix 096-695-E - Installation Requirements Applicable to New and Replacement Piping

1. Before underground piping is installed, a minimum 6-inch deep bed of well compacted noncorrosive material such as clean sand. pea stone or gravel must be placed in the trench. Trenches must be wide enough to permit at least 6 inches of noncorrosive backfill material around all lines.

2. Before being covered or placed in service, all new and replacement piping must be pneumatically tested for tightness with air pressure in accordance with the requirements of Appendix C, or hydrostatically tested in accordance with the requirements of Appendix D.

3. All temporary supports must be removed prior to final backfilling.

4. All vent piping for storage of Class One liquids must extend at least 12 feet above the ground surface and positioned such that vapors will not pose a hazardous condition.

5. Fill piping for storage of Class One liquids must be at least 5 feet or more from any building opening in accordance with National Fire Protection Association Code 30.

6. All leak detection devices must be tested for proper operation after installation and before initial use of the pumping system, and once annually thereafter. All leak detectors must be capable of detecting a leak at a rate of at least 3 gallons per hour at 10 pounds per square inch line pressure within 5 minutes.

7. Piping systems that use a suction pump(s) must be sloped from the pump(s) toward the tank(s).

8. Conventional suction systems must have no more than one check valve per pump. The check valve must be located as close to the pump as possible, such that any leaks in the line will result in a return of product to the tank.

9. For cathodically protected piping systems, access must be provided to the soil over the piping at the maximum distance from the anodes in order to monitor the cathodic protection in accordance with Appendix F and subsection 9(C) of this rule. This requires providing access through pavement and secondary containment liner systems if necessary.

10. Swing joints must not be used underground without written permission from the department. Flexible connectors must be used where technically feasible. Use of swing joints or other alternative methods will be allowed if the owner or operator demonstrates in writing to the commissioner's satisfaction that flexible connectors are not technically feasible and that swing joints or alternative methods will provide the best available protection of the environment and public health, safety and welfare.