Homeowners need to ensure that they have access to drink-able water, often referred to as "potable" water. There are generally two kinds of sources of drinking water. Some comes from reservoirs. The rest comes from groundwater, either through private wells, or wells that are owned by water supply companies. Recent reports are suggesting that many wells which supply drinking water in this country may be contaminated by a potentially harmful gasoline additive called "MTBE."

One major source: leaking gasoline underground storage tanks located at gas stations, trucking companies, and other locations. Many service stations have multiple tanks, one or more for regular unleaded, one for high test, and sometimes one for diesel fuel. A lot of the older underground tanks were made of metal that is now deteriorating and leaking. When gasoline containing underground storage tanks leak, gasoline often flows directly into ground water that is then collected in drinking water wells.

The problem is that gasoline often contains MTBE, a fuel additive that is technically called "methyl-tert-butyl ether." MTBE is added to gasoline throughout the United States to increase octane levels and to reduce smog forming carbon monoxide. The EPA considers MTBE to be a "possible human carcinogen," meaning that it may cause cancer in humans. Recent studies by the federal government have detected MTBE in 27% of the urban wells that were sampled. Under 2% of the agricultural area wells contained MTBE.

In 1997, the U.S. Geological Survey issued a report which concluded that the urban areas where MTBE was most commonly detected included Denver (79% of the wells), Harrisburg, Pennsylvania (37% of the wells), and various New England cities (also 37% of the wells).

At present, the EPA has established a drinking water limit for MTBE of 20 micrograms per liter. According to the government, lifetime exposure to MTBE below this level is not expected to cause harmful health effects. Three per cent of the sampled urban wells detected MTBE levels that exceed this safe level. However, MTBE has been placed on the EPA's "Drinking Water Priority List," which means that it will be subject to further study, and that the limit considered to be safe may be changed.

MTBE Affecting Several Communities Thus Far
Recently, homeowners throughout the United States have complained about MTBE. In July, residents of several Virginia communities learned that their drinking water contained the additive. Homeowners there attended community organization meetings to determine necessary steps to safeguard their water supply. MTBE has been detected at four times the safe level and there are thousands of wells that may have been impacted. MTBE sampling can cost several hundred dollars per well.

In August, Maryland health officials announced that MTBE levels over 100 times the safe level were found in one home's well water . According to local officials, that contamination may be linked to a leaking gasoline tank located at a nearby trucking company.

Responding to MTBE
When MTBE contamination is detected, there are several approaches that are available. If the problem is severe enough, an alternate drinking water supply may be required. This can mean providing bottled water, or connecting to a public water company. In other instances, filters or other water cleansing devices can be installed to a drinking water well to purify the water before it is consumed.

Recently, MTBE contamination prompted a California environmental group, Communities For A Better Environment, to file suit against eight oil companies. The suit alleges that while oil companies knew, or should have known, that MTBE may pose a health threat, the companies nonetheless added it to their gasoline. The City of Santa Monica, California, recently also sued oil companies because MTBE contamination forced the closure of half of its drinking water supply wells.

It appears that drinking MTBE isn't the only problem. Breathing it has also reportedly made some sick. In 1992, some 200 residents of Fairbanks, Alaska reported problems such as headaches and nausea after breathing air containing MTBE car exhaust. Similar complaints have also been registered in Montana, Wisconsin and New Jersey.

California has mounted an MTBE counter offensive by recently enacting three anti-MTBE laws. One, the Local Drinking Water Protection Act, appropriated $5 million annually to control MTBE discharges. Another law, the MTBE Public Health and Environmental Protection Act, provides for the study of MTBE to determine whether it poses a risk to human beings and requires additional safeguards to prevent MTBE from entering drinking water supplies.

What Should Homeowners Do?
The extent that MTBE represents a health hazard is still not known. However, the EPA, and others, suspect that at certain concentrations this substance can be dangerous if consumed.

If your drinking water is provided by a water supply company, you should ask whether that company obtains its water from wells. If so, you are entitled to request copies of the water sampling results. If MTBE contamination has been detected, you should evaluate the measures taken by the water company to address this problem.

If you rely on a private well, you must test your water at regular intervals. A qualified laboratory can assist you. If MTBE is detected, someone who is qualified should evaluate the results and advise you of your options.

The information provided in this column is written by Stuart Lieberman,a practicing environmental attorney, and is for general information purposes only. It is not legal advice and should not be used in place of legal advice.

Stuart Lieberman, Esq., and IRED.Com, Inc., will not accept any responsibilty for any reliance on the information in this column or any damages whatsoever resulting from reading this column.