Sec. 598.9. Maintenance and repair of facilities

(a) Repairs.

(1) Prompt action must be taken to prevent an imminent release. If any inspection shows that continuation of an operation or practice will result in a release or that the tank system, or any portion thereof, is inadequate or not tight, then the operation or practice must be modified or discontinued. The tank system, or any portion thereof, must be promptly replaced, repaired or taken out-of-service. Examples which may indicate that a release is imminent include, but are not limited to, leaking valves, pumps and pipe joints, malfunctioning pressure or vacuum relief devices, inadequate gauges, tightness test failures, excessive thinning of the tank shell which would indicate structural weakness when the tank is filled, and malfunctioning pressure or temperature gauges.

(2) If the tank system, or any portion thereof, or operation or practice is not in imminent danger of causing a release but an inspection shows that is malfunctioning, or is in disrepair and that a leak or release is likely or probable unless action is taken, then the operation or practice must be modified or discontinued, or the equipment must be repaired or replaced within 90 days, removed from service or temporarily closed. Examples of such equipment disrepair include, but are not limited to, secondary containment dikes with erosion or rodent damage, transfer station pads with cracks, deficiencies in coatings for preventing corrosion caused by exposure to the environment, malfunctioning leak monitoring equipment, and cathodic protection systems which fail to provide the necessary electric current to prevent corrosion.

(b) Tank linings.

(1) Tank linings must be compatible with the substance stored.

(2) Tanks may be lined in accordance with API 652, NLPA 631 (see section 598.1[j] of this Part) or in accordance with an equivalent consensus code, standard or practice developed by a nationally recognized association or independent testing laboratory. Linings of carbon steel tanks must be applied no later than eight hours after abrasive blasting and cleaning of the internal surface or in accordance with a consensus code, practice or standard developed by a nationally recognized association or independent testing laboratory. Visible rust, moisture or foreign matter must not be present.

(3) All linings must be of sufficient thickness, density and strength to form an impermeable shell which will not crack, soften, flake or separate from interior surfaces. The coating must maintain a permanent bond to the equipment.

(4) The lining’s coefficient of thermal expansion must be compatible with the equipment to which it is applied so that stress due to temperature changes will not be detrimental to the soundness of the lining.

(5) The lining material must be applied and cured in strict accordance with the manufacturer's specifications.

(6) The lining must be checked for blisters and air pockets and electrically tested for pinholes. The thickness of the lining must be checked with an Elcometer Thickness Gauge or equivalent method and the hardness checked with a Barcol Hardness Tester or equivalent method to assure compliance with manufacturer's specifications. Any defects must be repaired.

(7) The date of installation of the lining, condition of the tank, installation methods and other pertinent information must be kept in the spill prevention report for the lifetime of the tank system.

(c) Corrosion protection for tank systems.

By December 22, 1999, the exposed exterior surfaces of all aboveground systems must be protected from corrosion. Protection must be provided by using one or a combination of the following methods:

(1) corrosion resistant equipment materials such as stainless steel or Monel;

(2) non-metallic cladding, coal tar based epoxy coating or similar coating with a minimum finish thickness of 10 mils (0.01 inches);

(3) paints, consisting of an inhibitive primer coat, intermediate inhibitive and two or more final coats applied to a properly prepared surface or an equivalent or better surface coating as further specified in sections 599.8(f) and 599.13(c) of this Title; or

(4) an equivalent or better surface coating or corrosion protection system designed and installed in accordance with a consensus code, standard or practice of a nationally recognized association or independent testing laboratory.

(d) Replacement of rupture disks.

All rupture disks must be replaced with new ones at least every three years, or in accordance with any other frequency recommended by the disk manufacturer, or justified on the basis of operating experience in the spill prevention report.

(e) Vegetation.

No vegetation except grass shall be allowed to grow within secondary containment systems. Any grass within the secondary containment system must be trimmed to no longer than six inches. No accumulation of dead vegetation which could endanger the tank, if ignited, is allowed within the secondary containment system.

(f) Inspection of repaired equipment.

All repaired equipment must be inspected for tightness and soundness before it is returned to service.