Laserfiche WebLink
LG 150-2 Enclosure <br /> Summary Table <br /> Summary of Underground Storage Tank Overfill Prevention Options <br /> Health& Safety Code(H&SC), Sections 25281.5, 25290.1, 25290.2, 25291, and 25292 <br /> CCR,Title 23, Division 3, Chapter 16, Sections 2635, 2636, and 2665 <br /> H&SC 25291 H&SC 25290.1& <br /> 25290.2 <br /> Overfill Overfill Product Level Regulatory VentlTank Riser Vent/Tank Riser Piping VendTank Riser Piping <br /> Prevention System Prevention Citation Piping Subject to Subject to Secondary Subject to Secondary <br /> Mechanism CCR, Title 23 Corrosion Containment¢? Containment? <br /> "Examples" Protection? §2636(a)(1) <br /> §2636(b) <br /> Flow restrictor Ball float' 90% §2635(b)(2)(A) YES YES` YES <br /> External alarm Audible and 90% §2635(b)(2)(A) YES YES4 YES <br /> visual alarm <br /> At least 30 minutes <br /> Ball float' before tank overfills & <br /> filled to no more than <br /> Flow restrictor And 95%of tank capacity §2635(b)(2)(B) NO' NOS YES <br /> External alarm At least five minutes <br /> before tank overfills <br /> Positive shut off Fill tube valve 95% §2635(b)(2)(C) NO' NOS YES <br /> valve (flapper) <br /> Positive shut off Fill tube2 valve Below tank top fittings §2635(b)(2)(D) YES YES4 YES <br /> valve (flapper) <br /> 'In order to provide proper flow restriction,a ball float is required under all open risers except the fill riser and automatic tank gauging port. <br /> 2 If both types of overfill prevention systems(ball float and fill tube valve)are installed,the ball float may interfere with the operation of the fill tube valve if the ball <br /> float is installed lower than the fill tube valve. Therefore,the ball float should be installed at a higher level than the fill tube valve so that the fill tube valve is <br /> activated prior to any flow restriction. <br /> 'Corrosion protection is not required in this case because the vent/tank riser piping is exempt from the definition of"pipe"pursuant to H&SC§25281.5. However,it <br /> is a best management practice to provide corrosion protection for all corrodible piping in contact with the backfill. <br /> 4 Secondary containment is required at post July 1, 1987 installations because with this type of overfill prevention the components do not meet the exemption criteria <br /> of Section 2636(a)(1),CCR. <br /> S Single-walled components of UST systems may be a source of product or vapor releases to the subsurface environment,even if they do not routinely contain product. <br /> Therefore,we recommend installation of secondary containment on all UST components,including those currently exempt from this requirement. <br />