What is corrosion protection?

Unprotected underground metal components of the UST system can corrode and release product through corrosion holes. Corrosion can begin as pitting on the metal surface. As the pitting becomes deeper, holes may develop. Even a small corrosion hole can leak hundreds of gallons of petroleum into the surrounding environment over a year. In addition to tanks and piping, metal components can include flexible connectors, swing joints, and turbines. All metal UST system components that are in contact with the ground and routinely contain product must be protected from corrosion. All USTs installed after December 22, 1988 must meet one of the following performance standards for corrosion protection:
Tank and piping completely made of noncorrodible material, such as fiberglass-reinforced plastic.
Tank and piping made of steel having a corrosion-resistant coating AND having cathodic protection. (click here for more information on Cathodic Protection.)
Tank made of steel clad with a thick layer of noncorrodible material (this option does not apply to piping).
Tank and piping are installed without additional corrosion protection measures provided that a corrosion expert has determined that the site is not corrosive enough to cause it to have a release due to corrosion during its operating life and owners/operators maintain records that demonstrate compliance with this requirement.
Tank and piping construction and corrosion protection are determined by the implementing agency to be designed to prevent the release or threatened release of any stored regulated substance in a manner that is no less protective of human health and the environment than the options listed above.
UST systems must also be designed, constructed, and installed in accordance with a national code of practice and according to manufacturers instructions.
UST systems installed before December 1988 must be protected from corrosion. These USTs must meet one of the corrosion protection standards listed above or meet one of the upgrade options described below (or close properly):
Interior lining,
Cathodic protection*, and
Internal lining combined with cathodic protection*.
* NOTE: Prior to adding cathodic protection, the integrity of the tank must have been ensured using one of the following methods:
the tank is internally inspected and assessed to ensure that the tank is structurally sound and free of corrosion or holes,
the tank has been installed for less than 10 years and uses monthly monitoring for releases,
the tank has been installed for less than 10 years and is assessed for corrosion holes by conducting two tightness tests--the first occurs prior to adding cathodic protection and the second occurs 3 to 6 months following the first operation of cathodic protection, and
Alternative Integrity Assessment: the tank is assessed for corrosion holes by a method that is determined by the implementing agency to prevent releases in a manner that is no less protective of human health and the environment than those listed immediately above.
Upgrading bare metal piping is accomplished by adding cathodic protection. NOTE: Metal pipe sections and fittings that have released product as a result of corrosion or other damage must be replaced. Piping entirely made of (or enclosed in) noncorrodible material does not need cathodic protection.
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Why might you fail to be in compliance even if you have the required prevention equipment?
It takes more than equipment to be in compliance and to have a safe facility. You must operate and maintain this equipment properly over time or you will not benefit from having the equipment.
Failure to operate and maintain equipment can lead to new releases. A spill bucket that is allowed to crack or fill up with debris is useless as spill protection. An overfill device that is not maintained may not function and your site will suddenly have a large overfill release to clean up. Corrosion protection devices or systems that are not regularly operated and maintained properly can fail and result in an expensive cleanup at your UST site.
Be sure you review the information sources on our Web pages devoted to "Operation and Maintenance of USTs".
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How do you properly close an UST?
To properly close an UST:
Notify the regulatory authority at least 30 days before you close your UST.
Determine if contamination from your UST is present in the surrounding environment. If there is contamination, you may have to take corrective action. For at least 3 years, keep a record of the actions you take to determine if contamination is present at the site (or you can mail this record to your regulatory authority).
Either remove the UST from the ground or leave it in the ground. In both cases, the tank must be emptied and cleaned by removing all liquids, dangerous vapor levels, and accumulated sludge. These potentially very hazardous actions need to be carried out carefully by trained professionals who follow standard safety practices. If you leave the UST in the ground, have it filled with a harmless, chemically inactive solid, like sand.
NOTE: Check with your state to determine any state-specific requirements for closing UST systems.
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What are the reporting and recordkeeping requirements?
UST owners must notify state or local authorities of the existence of an UST and its leak prevention measures, or of the permanent closure of an UST. Technical regulations also set guidelines for notifying authorities of spills of more than 25 gallons.
Owners and operators must also keep records on:
Inspection and test results for the cathodic protection system.
Repairs or upgrades.
Site assessment results after closure
A corrosion expert's analysis of the corrosion potential of the site if corrosion protection equipment is not used.
Click here for more information on reporting and recordkeeping.
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Corrosion protection methods

"Corrosion Protection"...
Dave Wilson, Editor, writes:
We see from your search that you're looking for information on the term "Corrosion Protection", and we have a large number of manufacturers' news releases and technical articles here on Engineeringtalk which will be of interest. Let me be your guide. Start with the news release Choosing the right bearing coating from Schaeffler (UK), which we summarised at the time by saying "Dr Steve Lacey, Schaeffler UK Engineering Manager, discusses the importance of selecting the right coating or corrosion-resistant material for rolling bearings operating in harsh environments". A couple of weeks before, we featured the news release Metal chain resists corrosion from Tsubakimoto UK: "Tsubaki NEP chain uses a combination of three layers of surface coating, with a highly resistant base layer that bonds a harder wear-resistant coating onto the chain bushes". In October 2007, we covered the news from Britool concerning its Britool socketry range - take a look at Socketry range expands which says: "Britool's socketry range has received another 20 boxed socket sets, 15 sets of sockets on clip rails and five extension bar sets".

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