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MTBE In Drinking Water

MTBE In Drinking Water

Wednesday, October 22, 2003

An EWG analysis of data from state environmental agencies finds that drinking water supplies for over 15 million Americans are contaminated with MTBE, a suspected carcinogen added to gasoline that even at trace levels renders water undrinkable due to foul taste and odor. The new data emerge as Republican leaders are pushing to load pending energy legislation with a plan - backed by big oil companies and oil-state politicians - to shield MTBE manufacturers from pollution liability claims. The provision would shift cleanup costs to consumers and taxpayers. Water utilities, mayors, state attorneys general and environmentalists are fighting the proposal.

Water quality data obtained by EWG through the Freedom of Information Act and state Open Records Laws shows that MTBE, or methyl tertiary butyl ether, has been found in test samples of source water or finished drinking water from 1,515 public water systems in 28 states. An estimated 15 to 40 million people are served tap water by utilities with MTBE contamination somewhere in the system.

MTBE is an unregulated contaminant and water utilities are not required to test regularly for its presence in finished tap water. Not every consumer in every contaminated system is drinking MTBE, but if House Republican leaders have their way, every individual served water by these utilities will be forced to pay the full cost of MTBE cleanup.

California has the most severe contamination with 127 systems serving more than 30 million people reporting MTBE contamination somewhere in the system. Outside of California, the most extensive contamination is in New England and the Mid-Atlantic states, where Massachusetts, New York and New Hampshire each have over 150 water systems with MTBE contamination problems. These figures, the best available, do not include MTBE contamination of private wells. (Click here for state list)

The data also show the contamination is getting worse. The number of U.S. drinking water systems reporting MTBE contamination increased six-fold between 1996 and 2002, from 112 to 637, and the number of states reporting problems doubled from 11 to 22.

MTBE detections in drinking water are increasing


Year Number of
MTBE Detections
States with
MTBE detects
Systems with
MTBE detects*
1996 252 11 119
1997 333 9 179
1998 910 15 384
1999 878 14 339
2000 1,042 22 382
2001 1,706 23 665
2002 1,705 22 663
Total 6,348 28 1,515


* Column does not add because many systems take wells off-line when MTBE is detected and then do not retest those wells. These systems may not report MTBE contamination in subsequent years.

Source: Environmental Working Group. Derived from data obtained from state agencies.

In the majority of the affected communities, consumers are unaware of the contamination because water utilities take steps to protect them as soon as MTBE is detected. Contamination as low as 2 parts per billion of MTBE can produce a harsh chemical odor and taste that can cause tap water to be unpotable. EWG analysis found more than 700 communities with source or finished water levels at 2 ppb or higher MTBE. To cope with the problem, water utilities either blend MTBE-contaminated water with clean sources to dilute the chemical, install costly systems to remove it, or abandon affected wells and find new water sources.

The costs of such remedies for large cities alone could eventually reach $29 billion, according to the U.S. Conference of Mayors.

EWG found that MTBE contamination affects communities of all sizes - with contamination reported from large systems like San Diego, where the water utility serves 1.2 million people, to the Millbrook Country Day School in Massachusetts, serving 25 students and teachers. MTBE has been detected in water supplies serving 30 million people in California, about 2 million in both New Jersey and Massachusetts, 195,000 in Maryland and more than 900,000 in both Pennsylvania and Texas. (Click here for full state list)

In some cities, such as Santa Monica and South Lake Tahoe, Calif., a substantial portion of the local water supply has been contaminated, while in many others only one or two detections of MTBE have been made. But this last fact is less reassuring than it is worrisome. The records obtained by EWG indicate that in almost all systems with just one positive detection of MTBE, tests for the compound were conducted in the last two years. Water systems nationwide are in the middle of a years-long process of meeting federal requirements mandating testing for "unregulated contaminants" like MTBE. This suggests that MTBE is only now showing up in many drinking water systems, and detections will continue to increase for some time. That prospect makes the scheme to shield MTBE polluters from liability as part of national energy legislation all the more troubling.

Republicans Seek Protections for Polluters in Energy Bill

MTBE is an "oxygenate" that oil companies once claimed makes gasoline burn cleaner and more efficiently; it was introduced as a replacement when lead was banned from gasoline. But MTBE is also a foul-tasting and nasty-smelling compound that spreads rapidly when gasoline escapes from leaky underground storage tanks or other sources. Once in soil or water, MTBE breaks down very slowly while it accelerates the spread of other contaminants in gasoline, such as benzene, a known carcinogen.

Since 1995, the U.S. Environmental Protection Agency has classified MTBE as a possible cause of cancer in people. Eighteen states have passed measures to ban or significantly limit the use of MTBE in gasoline, and a nationwide ban is currently under consideration by Congress.

Hundreds of communities across the U.S. face many millions of dollars in costs to clean up MTBE contamination or find replacement water supplies. But the same proposal in Congress that would ban MTBE would also let the main culprits off the hook for the cleanup bill. (Click for USA Today - Energy bill provision may stop suits over water polluted by gas additive)

A paragraph buried deep in a massive federal energy bill, whose final form is now being hammered out by House and Senate negotiators, would give the makers and users of MTBE immunity from defective product lawsuits. That is precisely the legal theory that has been used by some communities to win multimillion-dollar damages from the oil companies for knowingly making, distributing and selling MTBE. Republican leaders Billy Tauzin (LA), Joe Barton (TX) and Tom Delay (TX) are the prime supporters of the liability shield.

Last year, a California jury in South Lake Tahoe found five oil and chemical companies liable for deliberately selling a defective product - MTBE - while failing to warn of its pollution risks. (Click for verdict) After the verdict, the companies agreed to pay $60 million in damages. Recently, the City of Santa Monica settled a similar lawsuit, with 18 oil companies agreeing to pay damages still to be determined.

If the MTBE liability shield is included in the final energy bill, it would make cities and local water districts powerless to force oil companies to pay for cleanup. While gas station owners could be sued over leaks, it is often difficult to trace precise sources of MTBE contamination, and most gas stations are small businesses unable to pay the millions of dollars often required to remedy MTBE pollution.

Oil Industry Claims Are Refuted By Internal Company Documents

The oil industry and its friends in Congress say it's only fair to shield MTBE makers from lawsuits, because they claim that the government mandated oil companies to add MTBE to gasoline in the first place, to help clean the air. But another story is told by internal industry documents and depositions made public in the California lawsuits. The documents, provided to EWG by attorneys for the communities, show it was the oil companies themselves who lobbied hard for the MTBE mandate because they made the additive and stood to profit.

A paper trail dating back almost 25 years shows how the oil companies took an unwanted byproduct of gasoline refining that was expensive to dispose of and created a profitable market for it. Beginning in the mid-1980s, well in advance of the 1992 federal mandate to reformulate gasoline to meet the standards of the Clean Air Act, the petrochemical industry promoted MTBE to U.S. and state regulators as the additive of choice - knowing at the time that it would very likely contaminate ground water. Only much later did the companies admit that MTBE doesn't do much to reduce air pollution after all.

In the South Lake Tahoe case, a top ARCO executive admitted under oath: "The EPA did not initiate reformulated gasoline . . . [T]he oil industry . . . brought this [MTBE] forward as an alternative to what the EPA had initially proposed." He testified that the EPA "was actually promoting using methanol blends" as an oxygenate. 

Secret oil company studies from as early as 1980 show the industry knew that MTBE contaminated ground water virtually everywhere it was being used. Despite that knowledge, by 1986, the oil industry was adding 54,000 barrels of MTBE to gasoline each day. By 1991, one year before the EPA required the use of oxygenates, the industry was using more than 100,000 barrels of MTBE per day in reformulated gasoline. 

A Shell hydrogeologist testified in the South Lake Tahoe case that he first dealt with an MTBE spill in 1980 in Rockaway, N.J., where seven MTBE plumes were leaking from underground storage tanks.  By 1981, when the Shell scientist wrote an internal report on the Rockaway plumes, the joke inside Shell was that MTBE really stood for "Most Things Biodegrade Easier." (Later, other versions of the joke circulated, including "Menace Threatening Our Bountiful Environment," or in an apparent premonition of the oil companies' legal vulnerability, "Major Threat to Better Earnings.")

Shell was not the only company with foreknowledge of MTBE contamination problems. An environmental engineer for ExxonMobil (the companies merged in 1999) testified that he learned of MTBE contamination from Exxon gasoline in 1980, when a tank leak in Jacksonville, Md., fouled wells for a planned subdivision. The ExxonMobil engineer said it was learned MTBE had also leaked into the subdivision's wells from a Gulf and an Amoco station. 

In 1981, an ARCO memo said leaking tanks were "a major problem.... The issue is essentially a health/safety and environmental one. Escaping vapors can seep into basements, sewers and conduits, creating not only a nuisance but the danger of explosion and/or fire. Escaping gasoline also enters and pollutes the water table. (Groundwater is a major source of the U.S. water supply.) Certain chemicals in gasoline (namely the aromatics like benzene) may be carcinogenic or toxic in certain quantities."

These and other documents prove that knowing fully well that their tanks leaked and that leaking MTBE had the potential to contaminate water supplies, ARCO and other companies not only went ahead and added MTBE to their gasoline, but agressively promoted it to state and federal regulators as an environmentally friendly product.

In 1987, a representative of ARCO Chemical, which was rapidly expanding its MTBE production, testified before the Colorado Air Quality Control Commission that the additive would reduce emissions and improve gas mileage and that consumers didn't need to be warned about the presence of MTBE in gasoline.  Nothing was said about the leak and contamination problems that ARCO and the rest of the industry had known about for at least seven years. ARCO's representative testified that in the 1980s he played a similar role in "assisting" the states of Arizona and Nevada in the development of oxygenate programs - programs that resulted in those states adopting MTBE. 

At the same time, the oil industry was agressively attacking non-industry studies that were beginning to find water pollution problems caused by MTBE.

In 1986, the Maine Department of Environmental Protection (DEP) published a report documenting extensive MTBE groundwater contamination in the state. The authors identified MTBE as a "rapidly spreading groundwater contaminant" and discussed the option that "MTBE could be abandoned as an additive in gasoline stored underground" or that gas with MTBE "be stored only in double-contained facilities."  

The Maine DEP report was perhaps the earliest warning from government health officials about the dangers of MTBE. To the oil companies, it was a call to arms. Documents show that even as they were internally disseminating this study and treating its findings seriously, the oil companies joined forces to attack the study's authors and the article's "damage" in an effort to discredit the findings and downplay the risks of MTBE. A 1987 ARCO memo detailed the continued attack on the authors and their research. 

Internally, however, the industry admitted the Maine paper was a threat precisely because it was scientifically credible. A 1987 letter from an ARCO refining executive to his Unocal counterpart admits the MTBE task force didn't "have any data to refute comments made in the paper that MTBE may spread further in a plume or may be more difficult to remove/clean up than other gasoline constituents."  

There were voices within the oil industry that warned against the use of MTBE, on grounds both of public health and cleanup costs from the inevitable leaks. An April 1984 memo from an Exxon employee said:

"[W]e have ethical and environmental concerns that are not too well defined at this point; e.g., (1) possible leakage of [storage] tanks into underground water systems of a gasoline component that is soluble in water to a much greater extent [than other chemicals], (2) potential necessity of treating water bottoms as a 'hazardous waste,' [and] (3) delivery of a fuel to our customers that potentially provides poorer fuel economy.... " (Emphasis added.)  

The memo was ignored by the employee's superiors.

The record is clear. Individual oil companies, and the industry as a whole, knew that adding MTBE to gasoline posed a serious threat to water supplies everywhere it was used. With full knowledge of the danger - but also of the profit they stood to make - they lobbied hard for the use of MTBE, then withheld or covered up evidence of its environmental and health risks.

Now that their own words and documents have surfaced to prove their culpability, oil companies offer one demonstrably false defense: "The government made us do it." And they are looking to Republican leaders to use the energy bill to protect them-instead of protecting water suppliers and consumers-from having to pay billions in cleanup costs for MTBE contamination in tap water.

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