CHAPTER 4. BUILDINGS AND CONSTRUCTIONCHAPTER 4. BUILDINGS AND CONSTRUCTION\Article 6. Petroleum Product Storage Tanks

This article regulates the installation, operation, leak detection, monitoring, and abandonment of aboveground and underground tanks used to store petroleum products, where such products are liquid, and at standard temperature and pressure.

(a)   Excluded from these regulations are:

(1)   Surface stock tanks used for storage of crude oil on leases.

(2)   Tank systems, individually owned and operated by agricultural farming systems.

(3)   Skid-mounted or portable tanks or tanks mounted on elevated supports except where indicated.

(Ord. 715, Sec. 1)

(a)   Abandoned Storage Tank. A tank taken permanently out of service as a storage vessel for any reason, or which has not been used for active storage for a period of more than one year.

(b)   Abnormal Loss. Any inventory measurement of the tank system contents which varies more than 0.5% from the delivered amount over a consecutive three day period that is not explainable by temperature variation or measurement accuracy.

(c)   Aboveground Storage Tank. Any tank that is not buried, including tanks inside buildings, whether above or below outside ground level.

(d)   Active Storage Tank. Any tank system other than (b), (c) or (d).

(e)   Buried Tank. Any tank where any part of the tank or vessel is buried below the ground surface.

(f)   Department. The building inspection department.

(g)   Fluid Pressure Loss Test. Any test in which the storage tank product is used to fill the tank distribution system prior to applying pressure to determine the tank system tightness.

(h)   Groundwater Table. The elevation below which the sediments are saturated with water.

(i)    Leak Detector. A device which, when installed on a pressure system, will provide an indication if the piping and dispenser are essentially liquid tight.

(j)    Tank System. Tanks and associated piping used to transfer petroleum products.

(k)   Temporarily Abandoned. Any tank that has been out of active service from 180 days to one year.

(l)    Temporarily Out of Service. Tanks which will remain out of service for a period of more than 30 days, but less than 180 days.

(Ord. 715, Sec. 2)

All new or replacement tank systems shall be installed in a way that will as nearly as is feasible preclude the possibility of leakage and resultant pollution, and provide for a monitoring system designed to facilitate early detection of leaks.

(a)   All new or replacement aboveground tanks shall comply with the following:

(1)   Shall be installed on an impermeable raised base or foundation so that leaks can be readily detected. The thickness and bearing characteristics of the foundation or base shall be in conformance with accepted installation practices. In all cases, the base of the tank shall be at an elevation above the adjacent ground surface; otherwise, the installation shall be considered an underground tank.

(2)   Storage tank systems having a capacity in excess of 2,000 gallons shall be protected by retention structures to prevent flowaway of overflow or spilled liquids. Each retention structure shall be constructed with sufficient capacity to contain the entire contents of the largest tank within the enclosure.

(b)   Underground storage tanks shall be installed so that they satisfy the following:

(1)   Tanks shall be set in an excavation having a base consisting of impervious material approved by the department. The base of the excavation shall be sloped so that any leakage from the tank will move to a collection basin. A perforated observation pipe composed of non-conductive material of at least four inches in diameter shall be installed to the bottom of the collection basin, shall extend to the surface, and be equipped with a watertight cap. Tank excavations located in areas where the water table continuously extends above the base of the tank need not include a collection basis, but a perforated observation pipe shall be installed from the base of the tank to the surface.

(2)   A minimum of six inches of sand or other approved highly porous bedding material approved by the tank manufacturer shall be placed between the floor of the excavation and the installed tank to act as a cushion for the tank and serve as a conduit to transmit leakage to the underlying impervious material or liner.

(3)   The monitoring (observation) system for piping connections shall be so located as to provide ready access to the facility operator or department personnel.

(4)   Leak detectors shall be installed on all new storage systems where underground pressure piping exists between the pump and a dispenser, except that detectors shall not be required for agricultural farming systems with less than 50 feet of delivery piping.

(5)   Anchoring systems shall be used to prevent tank flotation due to a high water table. Plan for anchoring systems shall be submitted for approval as described in section 4-609.

(c)   Any tanks excavated for repair shall be reinstalled in conformance with these regulations.

(Ord. 715, Sec. 3)

(a)   Accurate daily inventory control records shall be maintained by the person in control of the premises for each tank system for the purpose of detecting system leakage, except that storage tanks used in farming operations shall be exempted. Daily records shall be kept at the premises and made available to a representative of the department and other appropriate state and local agencies during reasonable hours.

(b)   Whenever an abnormal loss of stored petroleum products has occurred or the monitoring system indicates that leakage has occurred, the person in control of the premises shall immediately report the loss or leakage to the department by telephone and confirm the report by letter.

(Ord. 715, Sec. 4)

All new or replacement underground tank systems, or systems taken out of service for a period of more than six months shall be tested prior to use to determine that there are no holes or points of potential leakage. Testing may be accomplished by conducting a fluid pressure loss test or other test method approved by the department. The method or methods used and the results of the tests shall be submitted to the department within 10 days of the test completion. Within 10 days after receiving the test results, the department shall approve the use of the tank system, require additional tests or require repair or abandonment of the tank system. No such tank system shall be used until approved by the department. Pressure testing of all piping associated with the tank shall be required as part of the test.

(Ord. 715, Sec. 5)

Whenever pollution by a petroleum product subject to these regulations occurs and the source is unknown, the owners, operators or parties responsible for tank systems determined by the department to be potential sources of the pollution shall:

(a)   Submit inventory records for a six month period prior to the discovery of the escaped petroleum products.

(b)   Upon receipt of instructions from the department and without undue delay, cause each tank system to be tested.

(Ord. 715, Sec. 6)

(a)   When a tank is temporarily abandoned, all remaining liquid petroleum shall be removed to an active storage tank within 210 calendar days of the date of last active use.

(b)   The fill pipe and gauge opening shall be sealed with a cap approved by the department. The product lines shall be capped if the pump is removed. Pumps may remain connected if they are locked and electric power is shut off.

(c)   The vent pipe shall be left open.

(Ord. 715, Sec. 7)

(a)   Tanks that have been excavated shall be drained and the petroleum products disposed of in a manner which will not result in pollution or entrance of petroleum into any sewer system.

(b)   Tank systems that are abandoned in place constitute a violation of Article 2 of Chapter 8 of this Code and shall subject the owner thereof to prosecution in the City’s Municipal Court and/or the abandoned tank systems to be abated by the City pursuant to said Article.

(c)   A record of each tank removal shall be filed with the department within 30 days from project completion by the person in control of the facility.

(Ord. 715, Sec. 8; Ord. 2020, Sec. 1)

All plans for new and replacement underground tank systems shall be submitted to the department prior to the beginning of installation. The department shall approve, deny or require modifications within 10 days after receipt of the plans. All plans shall at least include the following:

(a)   A construction plan of the tank system showing the manner of tank installation and the location and the design of the collection basin and monitoring system.

(b)   Location of leak detector connections to be installed on a pressure system to monitor loss of product from piping or the dispenser.

(c)   The type of impervious material or liner to be used in the bottom of the excavation for leakage collection.

(d)   A description of the natural soil or bedrock conditions immediately surrounding or underlying the excavation and the proposed location of any devices to be used to prevent corrosion or electrolysis of the tank material.

(e)   Boring or excavation information used to determine the static water level of the area.

(f)   The type of anchoring system to be utilized to prevent flotation if the tank is to be installed where the water table is shallower than the base of the tank.

(Ord. 715, Sec. 9)