"Scope and Purpose This publication recommends procedures for the closure in place@ removal@ storage@ and off-site disposal of underground storage tank systems that have contained flammable or combustible fluids. In general@ it outlines requirements@ procedures@ and operating conditions to be followed by contractors@ engineers@ and other individuals who may be involved in these practices. While this recommended practice specifically addresses underground petroleum storage tank systems at service station facilities@ the principles outlined may be applied to similar systems used at other petroleum storage facilities. All such work must be accomplished in accordance with federal@ state@ and local requirements as well as accepted safety standards. Before initiating work@ the appropriate government agencies should be notified and consulted concerning applicable regulatory and permit requirements. All applicable permits must be obtained prior to beginning any work. Certified or licensed contractors may be required in some states. Consult the implementing agency for contractor requirements. Contractors@ subcontractors@ and their employees responsible for tank closure in place or removal should be familiar with: a. All applicable safety rules and regulations@ including OSHA's Occupational Safety and Health Standards (29 Code of Federal Regulations Part 1910). b. The use of equipment and procedures for testing and vapor-freeing tanks. c. The handling and disposal of the types of wastes likely to be encountered d. The applicable sections of the publications referenced in 1.4. Under applicable federal regulations@ including 40 Code of Federal Regulations Part 280@ an underground storage tank system (UST) consists of the underground storage tank and the connected underground piping@ underground ancillary equipment and containment system@ if any. The procedures outlined in this recommended practice can be applied to all portions of an underground storage tank system. The procedures outlined in this recommended practice can be carried out without entering the tank. Should tank entry be desired@ the procedures outlined in APIPublication 2015@ 2015A@and2217 and API Recommended Practice 1631 should be followed. See also 29 Code of Federal Regulations Part 1910.147 regarding ""Permit required confined space."" "