n 2017, PEI published three updated editions of PEI
recommended practices (RPs) that play prominent roles in
the 2015 federal underground storage tank (UST) regula-
tions. They are:
• RP100: Recommended Practices for Installation of
Underground Liquid Storage Systems.
• RP900: Recommended Practices for the Inspection and
Maintenance of UST Systems.
By Rick Long