Section 296-307-44011 - Installation of storage containers(1) Each storage container used exclusively in service station operation must comply with the following table. This table outlines the minimum distances from a container to a building, group of buildings, or adjoining property lines that may be built on. | Minimum distances |
| Watercapacity percontainer(gallons) | Abovegroundand underground(feet) | Betweenabovegroundcontainers(feet) |
| Up to 2,000 | 25 | 3 |
| Over 2,000 | 50 | 5 |
| Note: | The above distances may be reduced to at least 10 feet for service station buildings of other than wood frame construction. |
(a) Readily ignitible material including weeds and long dry grass, must be removed within 10 feet of containers.(b) The minimum separation between LP-gas containers and flammable liquid tanks must be 20 feet and the minimum separation between a container and the centerline of the dike must be 10 feet.(c) LP-gas containers located near flammable liquid containers must be protected against the flow or accumulation of flammable liquids by diking, diversion curbs, or grading.(d) LP-gas containers located within diked areas for flammable liquid containers are prohibited.(e) Field welding is permitted only on saddle plates or brackets that were applied by the container manufacturer.(f) When permanently installed containers are interconnected, the employer must allow for expansion, contraction, vibration, and settling of containers and interconnecting piping. Where flexible connections are used, they must be approved and designed for a bursting pressure of at least five times the vapor pressure of the product at 100°F. Using nonmetallic hose is prohibited for interconnecting containers.(g) Where high water table or flood conditions may be encountered, the employer must protect against container flotation.(2) Aboveground containers must be installed according to this section. (a) Containers may be installed horizontally or vertically.(b) Containers must be protected by crash rails or guards to prevent physical damage unless they are protected by location. Servicing vehicles within 10 feet of containers is prohibited.(c) Container foundations must be of substantial masonry or other noncombustible material. Containers must be mounted on saddles that permit expansion and contraction, and must provide against excess stresses. Corrosion protection must be provided for tank-mounting areas. Structural metal container supports must be protected against fire. | Exception: | This protection is not required on prefabricated storage and pump assemblies, mounted on a common base, with container bottom a maximum of 24 inches above ground with water capacity of 2,000 gallons or less, if the piping connected to the storage and pump assembly is flexible enough to minimize breakage or leakage in case container supports fail. |
(3) Underground containers must be installed according to this section.(a) Containers must be given a protective coating before being placed underground. This coating must be equivalent to hot-dip galvanizing or to two coatings of red lead followed by a heavy coating of coal tar or asphalt. During installation, take care to minimize abrasion or other damage to the coating. Repair coating damage before back-filling.(b) Containers must be set on a firm foundation (firm earth may be used) and surrounded with earth or sand firmly tamped in place. Backfill should be free of rocks or other abrasive materials.(c) A minimum of 2 feet of earth cover must be provided. Where ground conditions make impractical, equivalent protection against physical damage must be provided. The portion of the container to which manhole and other connections are attached may be left uncovered. If there is vehicle traffic at the site, containers must be protected by a concrete slab or other cover to prevent the weight of a loaded vehicle imposing a load on the container shell.Wash. Admin. Code § 296-307-44011
Amended by WSR 20-21-091, Filed 10/20/2020, effective 11/20/202097-09-013, recodified as § 296-307-44011, filed 4/7/97, effective 4/7/97. Statutory Authority: RCW 49.17.040,[49.17.]050 and [49.17.]060. 96-22-048, § 296-306A-44011, filed 10/31/96, effective 12/1/96.