The task group for revision of the 4th edition of the American Petroleum Institute (API) Recommended Practice (RP) 1604 Closure of Underground Petroleum Storage Tanks is virtually complete, and the new edition should be published soon.

Eleanor Jennings of environmental microbiology and biogeochemistry and Phillip Myers PE, BS & MS of chemical engineering, both at University of California, co-chaired the revision task group.

Myers said: “The Recommended Practice covers the procedures for closure, removal, storage, and off-site disposal of underground storage tank (UST) systems that have contained petroleum liquids. These tanks represent both an environmental as well as safety hazard, so we updated the reference to the latest safety and regulatory standards and aligned the language to be consistent with the consensus regulations that govern these tanks in many states.”

He added: “Where some states have few rules on these tanks, they should always be aware of and apply the principles outlined in this RP. One of the significant changes I brought to the table was to ensure that we included the reference to NFPA 326 Standard for the Safeguarding of Tanks and Containers for Entry, Cleaning, or Repair which is a relatively new NFPA standard. We also reference the latest version of API 2015 Requirements for Safe Entry and Cleaning of Petroleum Storage Tanks.”

As to the reason for the changes, he said: “I have been personally involved with too many serious and sad incidents involving serious injuries or fatalities associated with tank entry and cleaning for both above and belowground tanks. NFPA 326 and API 2015 (both referenced in this RP) both represent the state-of-the-art for ensuring the safety of this activity. For this reason alone, everyone who is thinking about this activity should consider API 1604 a must-have document.”

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9th February 2021