Many underground storage tanks have leaked over the years and their contents have hurt the environment. Leaking tanks can pollute the underground streams called "aquifers," and in turn, can hurt our drinking water supplies.

Even when tanks don't affect drinking water sources, vapors from underground leaks can enter building foundations. Scientists are only now realizing the magnitude of vapor intrusion issues. It's in all of our interests to stop these tanks from leaking.

How do we do this? First, if possible, don't put them in the ground. Many homeowners now have heating oil tanks in their basements. In my view, that is a far better option.

But for some tanks, there is no above ground option. For example very large gasoline tanks at service stations, as well as very large heating oil tanks for apartment and office buildings, usually are below grade, if not underground.

And in some cases, the tanks are not readily removable. So even if you wanted to take them out, it is not cost effective.

Enter Amor Shield. Since the 1960s, this company, through a national network of affiliates, has protected the environment by lining tanks to avoid leaks. Tank liners are actually fabricated inside large tanks . They are truly built to order, according to Jeff Colner, a Vice President of Operations. He has been with the company for 14 years.

Amor Shield will enter a tank through an opening called a "manway." When a manway doesn't exist, the company will construct one.

Many tanks are huge, often eight feet high and 30 feet long. So there is enough room to get the job done.

The company made a lot of money through the 1980s relining gas station tanks. This was needed to make sure that the tanks met then emerging federal requirements.

Jeff told me about a "ticking time bomb" in the industry: large heating oil tanks that serve many post-World War II buildings. He said many of these tanks are the older, single wall variety, waiting to leak. Often, they are so big that they simply cannot be removed.

His company's solution, installing a liner, has a lot of appeal for two reasons. First, it works. And second, it is much less costly than pulling the old tank and replacing it (if that is even possible).

Jeff sees this as an important market that needs national attention. These tanks can leak and cause serious environmental problems. Clearly, installing a liner before a problem develops makes a lot of sense for everyone involved.

Often insurance companies pay a lot of money when tank leaks cause ground water contamination. I think that insurance companies should be willing to pay some of the costs of preventative liner installations. Such an approach would be very smart because in the long run, the carriers would save money and we would protect the earth. We only have one earth, after all.

Amor Shield is reachable 24 hours at 888-839-0373. Because some calls are emergency calls with active tank leaks, a knowledgeable company representative is always available, according to Jeff.