Corrosion and Cathodic Protection

The earth has a natural electric current that occurs in water and land alike. These electrical currents have an adverse affect on metal objects that are in the ground or in the water. This adverse affect is called electrolysis and will literally drill a small hole through a metal object. Underground propane tanks are subject to electrolysis and need to be protected to avoid the deteriorating effect that results. To protect a tank from electrolysis, an anode bag is attached by wire to the tank and placed in the hole with the tank before it is covered with backfill. This sacrificial anode bag absorbs the electrical currents in the earth that would have ordinarily targeted the tank resulting in damage to the container. In short, the sacrificial anode bag acts as a "decoy" for the damaging currents that can harm a tank in an underground environment. 

Corrosion is an aggressive form of rusting. Underground steel tanks corrode do to an electrochemical reaction between the tank and the surrounding soil. To protect a tank from electrolysis, which occurs in the ground naturally, two commonly applied protection methods are used: external coating and Cathodic protection. The external coating is the first step and does most of the protection. But no coating is perfect. Damage to or imperfections in the coating may result in accelerated corrosion at the defect. Cathodic protection aims to prevent corrosion at those defects. This is done with the use of a sacrificial anode bag buried in the ground that will alter the electrical currents in the earth that would have targeted the tank resulting in damage. Periodically these anode bags need to be replaced for the protection to remain effective. For more than this elementary explanation please contact your propane provider.

Corrosion could lead to a leaking tank creating all sorts of problems:

• The customer will lose gas costing him or the propane company money for lost propane.
• The longevity of the steel tank will decrease if not protected.
• The customer or propane company could be fined if neglecting these regulations. 
• If something were to happen your insurance company may demand documented proof of positive testing results.

And most importantly, propane may migrate to the crawl space and into the house creating a dangerous situation.

These tests need to be done and documented every three years making it even tougher for the propane companies to keep up with the testing requirements. Furthermore it may make sense to have a third party, independent, unbiased company to perform this testing.

This eliminates the idea that fraudulent or forged test results are being created for compliance to these regulations.

It could eventually be insisted that a third party do the testing for these reasons.

We perform the tests for you and your propane provider. We will email you and your provider the results. These are independent, unbiased documented results required by law.