UST Technical Compendium Category 2: New/Upgraded UST Systems (NUS)
NOTE: QA documents referred to in some of the following responses may be outdated. Visit The EPA Quality System web site for the latest version of EPA's QA documents.


Question 14: What are the monitoring/inspection requirements when using the combination of internal lining and cathodic protection (CP) as a corrosion upgrade option? 
Answer: There are three scenarios that might occur when using this corrosion upgrade option. They are: 
1. Applying internal lining and CP at the same time.  
2. Applying CP to an UST with an internal lining.  
3. Applying an internal lining to an UST with CP. 
 For all options, the CP system needs to be monitored in accordance with 40 CFR Part 280.31. Periodic inspections of the lined tank are not required if the integrity of the UST was ensured prior to the addition of CP. Because integrity assessment is part of the industry lining codes, this will be the case in scenarios 1 and 3, but not necessarily 2. For example, if CP is added to an UST that was lined 5 years ago, but the integrity of the UST was not ensured prior to adding the CP, then periodic inspections of the lined tank are required.  
[December 4, 1995 memorandum to State and Regional Program Managers (PDF) (4 pp, 15K)]

http://epa.gov/oust/compend/nus.htm
