Wyoming Administrative Code
Agency 020 - Environmental Quality, Dept. of
Sub-Agency 0011 - Water Quality
Chapter 17 - STORAGE TANKS
Part B - STORAGE TANK SYSTEMS: TECHNICAL SPECIFICATIONS
Section 17-6 - Design and Construction Standards for UST Systems

Universal Citation: WY Code of Rules 17-6

Current through September 21, 2024

In order to prevent releases due to structural failure, corrosion, or spills and overfills for as long as the UST system is used to store regulated substances, all owners and/or operators of UST systems shall meet the following requirements.

(a) Tanks. Each tank shall be properly designed, constructed, and installed, and any underground component that routinely contains regulated substances shall be protected from corrosion, in accordance with a code of practice developed by a nationally recognized association or independent testing laboratory as specified below:

(i) Fiberglass-Reinforced Plastic tanks shall be manufactured and installed in accordance with one or more of the following industry standards or practices:
(A) UL Standard 1316, "Standard for Glass-Fiber-Reinforced Plastic underground storage tanks for Petroleum Products"; or

(B) ASTM Standard D 4021-1992, "Standard Specification for Glass-Fiber-Reinforced Polyester underground storage tanks."

(ii) Cathodically Protected Steel USTs shall be manufactured and installed to meet the following requirements:
(A) The outside surface of all steel tanks installed after the date of these regulations shall be coated with a suitable dielectric material;

(B) Field-installed CP systems shall be designed by a corrosion expert;

(C) Impressed current CP systems shall be designed to allow determination of current operating status as required in Section 11, including a voltage meter, an amperage meter, and an hour meter showing the hours that the rectifier actually operated; and

(D) CP systems shall be operated and maintained in accordance with Section 11. Once installed, CP systems shall not be removed as long at the steel UST system exists.

(E) In addition to the above requirements, all cathodically protected steel USTs shall be manufactured and installed in accordance with one or more of the following industry standards or practices:
(I) STI, "Specification for STI-P3 System of External Corrosion Protection of Underground Storage Tanks"; or

(II) UL Standard 1746, "Corrosion Protection Systems for underground storage tanks"; or

(III) NACE Standard RP0285-2002, "Control of External Corrosion on Metallic Buried, Partially Buried, or Submerged Liquid Storage Systems"; and UL Standard 58, "Standard for Steel Underground Tanks for Flammable and Combustible Liquids."

(iii) Steel-Fiberglass-Reinforced-Plastic Composite tanks shall be manufactured and installed in accordance with one or more of the following industry standards or practices:
(A) UL Standard 1746, "Corrosion Protection Systems for Underground Storage Tanks"; or

(B) Association for Composite Tanks ACT-100, "Specification for the Fabrication of FRP Clad Underground Storage Tanks".

(iv) Interior lining: Owners and/or operators may continue to operate tanks upgraded with an internal lining without added CP if:
(A) Within ten (10) years after lining, and every five (5) years thereafter, the lined tank is internally inspected and found to be structurally sound with the lining still performing in accordance with original design specifications. This requires that the tank be entered and cleaned out to allow an internal inspection; and

(B) The lining was installed in accordance with the requirements of API Publication 1631, "Recommended Practice for the Interior Lining of Existing Underground Storage Tanks", or

(C) The lining was installed in accordance with the requirements of the National Leak Prevention Association Standard 631, "Spill Prevention, Minimum 10 Year Life Extension of Existing Steel Underground Tanks by Lining Without the Addition of CP".

(v) New steel tanks shall not be installed with a liner without the addition of CP. No existing steel tank with a liner and added CP shall be modified to remove the CP.

(vi) After the effective date of these regulations, no UST may be installed for any purpose regulated by this program with any penetration into the UST except in the top.

(vii) All USTs installed in Wyoming after the effective date of these regulations shall be anchored using deadmen to prevent flotation. No tank shall be installed without providing for the maximum possible buoyancy force assuming that the tank is completely under the local groundwater table. No tank shall be installed using a concrete slab above the tank as the primary method of resisting buoyancy forces.

(b) Piping. Piping that routinely contains regulated substances and is in contact with the ground shall be properly designed, constructed, installed, and protected from corrosion in accordance with the following applicable industry standards or practices:

(i) Fiberglass-Reinforced Plastic piping shall be manufactured and installed in accordance with one or more of the following industry standards or practices:
(A) UL Subject 971, "UL Listed Non-Metal Pipes"; or

(B) UL Standard 567, "Pipe Connectors for Flammable and Combustible and LP Gas."

(ii) Steel piping shall be cathodically protected in the following manner:
(A) The piping shall be coated with a suitable dielectric material;

(B) Field-installed CP systems shall be designed by a corrosion expert;

(C) Impressed current CP systems shall be designed to allow determination of current operating status as required in Section 11; and

(D) CP systems shall be operated and maintained in accordance with Section 11.

(E) In addition to the above, cathodically protected steel pipe shall be manufactured and installed in accordance with one or more of the following industry standards or practices:
(I) NFPA Standard 30, "Flammable and Combustible Liquids Code";

(II) API Publication 1615, "Installation of Underground Petroleum Storage Systems";

(III) API Publication 1632, "Cathodic Protection of Underground Petroleum Storage Tanks and Piping Systems"; or

(IV) NACE Standard RP0169-2002, "Control of External Corrosion of Submerged Metallic Piping Systems";

(iii) Other Piping systems will be allowed if they are determined by the department, pursuant to Section 33 of this chapter, to be designed to prevent the release of any regulated substance in a manner that is no less protective than the requirements in Section 6(b).

(c) Spill and overfill prevention equipment.

(i) Except as provided in Section 6(c) (ii), to prevent spilling and overfilling associated with regulated substance transfer to the UST system, owners and/or operators shall use the following spill and overfill prevention equipment:
(A) Spill prevention equipment that will prevent release of regulated substances to the environment when the transfer hose is detached from the fill pipe (for example, a spill catchment basin); and

(B) Overfill prevention equipment that will:
(I) Automatically shut off flow into the tank when the tank is no more than ninety-five percent (95%) full; or

(II) Alert the transfer operator when the tank is no more than ninety percent (90%) full by restricting the flow into the tank or triggering a high-level alarm.

(ii) Owners and/or Operators are not required to use the spill and overfill prevention equipment specified in Section 6(c)(i) if the UST system is filled by transfers of no more than twenty-five (25) gallons at one time.

(d) Installation. All tanks and piping shall be properly installed in accordance with one of the following industry standards or practices and in accordance with the manufacturer's instructions:

(i) API Publication 1615, "Installation of Underground Petroleum Storage Systems"; or

(ii) PEI Publication RP100, "Recommended Practices for Installation for Underground Liquid Storage Systems".

(iii) ANSI Standard B31.3, "Petroleum Refinery Piping," and ANSI Standard B31.4 "Liquid Petroleum Transportation Piping System."

(e) Certification of Installation. No storage tank system shall be operated until the department determines the installation or substantial modification meets the applicable standards of this part. The department shall not issue any such determination until all construction on the site of the storage tank system is complete. Owners and/or operators shall:

(i) Notify the department by telephone or in writing at least thirty (30) days prior to the installation, repair or substantial modification of any storage tank system. Installations, repair or substantial modifications shall be scheduled at mutually acceptable times so that the department can ensure a representative is on site at various phases of installation or substantial modification. Inspections shall be completed within ten (10) days of the date when the department is notified that the installation, repair or substantial modification is complete; and

(ii) Pay the department a fee for each storage tank system or multiple storage tank systems installed, repaired or substantially modified at the same time and at the same site pursuant to W.S. 35-11-1420(c). The department will invoice the owner and/or operator upon completion of the final installation, repair or substantial modification inspection. The owner and/or operator shall remit payment to the department within thirty (30) days of receipt of the department's invoice; and

(iii) Ensure that the installation or substantial modification of all USTs meets the performance standards of this part; and

(iv) Obtain a certification from the installer, or person modifying the UST, certifying that the tank was installed or modified to meet the requirements of this part. Such certification shall be provided on the UST notification form required under Section 9; and

(v) In the case of an emergency where the owner and/or operator cannot comply with the notification requirement of Section 6(e)(i), notify the department by telephone as soon as the emergency is found. Before proceeding with any substantial modification or installation:
(A) The department shall determine whether an inspection can be made within the owner and/or operator's schedule of work; or

(B) If the department cannot make the inspection, the owner and/or operator shall provide by mail, the specifications of materials and industry standards or practices used to accomplish the installation or substantial modification and documentation of any tests required within five (5) days of completion.

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