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Storage Tanks Were Known to be Leaking in the 1970s and 1980s

MTBE With Knowledge: Storage Tanks Were Known to be Leaking in the 1970s and 1980s

September 28, 2002

Storage Tanks Were Known to be Leaking in the 1970s and 1980s

Refiners also knew that underground gasoline storage tanks were susceptible to leaks, a fact that would amplify the problem with MTBE. In 1973, an Exxon report on the problem said: “The subject of underground leaks at service stations is one of growing concern to gasoline marketers. Large sums of money, time, and effort are exhausted on a continuing basis in the location and detection of leaking tanks and lines.” [Excerpt | Full document]

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.” [View document]

By 1980, Exxon had an annual testing program for tanks and found that 27 percent were leaking; two years later the failure rate was up to 38 percent. [View document] In 1981, Shell and ARCO, the first refiners to add MTBE, estimated that 20 percent of all U.S. underground storage tanks were leaking. [View document] Five years later, in 1986, the EPA concurred. [Excerpt | Full document] Prior knowledge of the extent of leaking gasoline storage tanks was a major part of South Lake Tahoe’s case: Fully aware that tanks were leaking, the petrochemical industry nonetheless introduced an additive known to rapidly percolate down to groundwater from gasoline distribution systems with known leaks. Efforts were ongoing to upgrade storage tank systems, but when industry learned quickly that the new tanks were still leaking, it continued to expand the use of MTBE anyway.

The Industry, not the EPA, Promoted MTBE as an Oxygenate

Recently disclosed court documents clearly show that the oil companies, not state or federal regulators, were the boosters of MTBE. The industry developed and promoted the concept of using reformulated gasoline to reduce air emissions, assuring the EPA that reformulated gasoline would be better than other options being considered. ARCO Chemical Co.’s Manager of Business Development from 1987 to 1998 testified: “What I recall is the EPA actually promoting using methanol blends... and the refining industry said here’s another option... we can reformulate gasoline to reduce the emissions... that would be equal to or better than you would get by substituting or mandating the use of methanol vehicles... [T]he oil industry... brought this forward as an alternative to what the EPA had initially proposed.” He continued, “The EPA did not initiate reformulated gasoline.” [Excerpt | Full document]

Well before the EPA mandated reformulated gasoline in 1992, the oil industry was aggressively promoting MTBE. According to the American Petroleum Institute, refiners were adding an average of 74,000 barrels of MTBE to gasoline per day from 1986 through 1991, roughly one third of the peak amount added to gasoline in 1998. [View document]

In 1987, a representative of ARCO Chemical (later absorbed by Lyondell), 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, that supply and price were no barrier, and that consumers didn’t need to be warned about the presence of MTBE in gasoline. [Excerpt | Full document] 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. [Excerpt | Full document]

The Industry Attacked Safety Studies and Withheld Information From Regulators

In 1986, the Maine Department of Environmental Protection 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.” [Excerpt | Full document] The Maine Paper 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 their findings and downplay the risks of MTBE.

The industry disinformation effort began even before publication of the paper. A 1987 ARCO memo details the continued attack on the authors and their research:

“We initially became involved with the Maine DEP prior to the presentation of their first version of this paper at the National Well Water Conference on November 13, 1986... Since the paper was presented last November, we have been working with API, the newly formed MTBE Committee [of the Oxygenated Fuels Association], and on our view to assess the potential impact of this paper on state policymakers [and] to contain the potential ’damage’ from this paper....“ [View document]

The memo goes on to explain how the Maine Petroleum Council, the state affiliate of the API, was preparing a paper claiming that MTBE didn’t speed up the spread of benzene in water, that MTBE “only spreads slightly further” than benzene and other contaminants, and that MTBE could be easily removed from water with existing technology – none of which is true. Internally, however, the industry admitted the Maine paper was a scientifically credible threat. 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.” [View document]

In 1987, at the same time that ARCO and API were leading the attack on the Maine Paper, the U.S. EPA issued a request to the industry for “more information on the presence and persistence of MTBE in groundwater.” As reported last year by the San Francisco Chronicle and The Sacramento Bee, ARCO responded: “Where gasoline containing MTBE is stored at refineries, terminals or service stations, there is little information on MTBE in groundwater. We feel that there are no unique handling problems when gasoline containing MTBE is compared to hydrocarbon-only gasoline.” [View document]

Internal Memos Warning Against MTBE Were Ignored

There were voices within the industry that warned against the use of MTBE, on grounds both of public health and cleanup costs from the inevitable leaks. A document dated April 3, 1984 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.) [View document]

That same year, an Exxon engineer wrote the first in a series of memos outlining “reasons MTBE could add to ground water incident costs and adverse public exposure:”

“Based on higher mobility and taste/odor characteristics of MTBE, Exxon’s experiences with contaminations in Maryland and our knowledge of Shell’s experience with MTBE contamination incidents, the number of well contamination incidents is estimated to increase three times following the widespread introduction of MTBE into Exxon gasoline....” Later, the document notes: “Any increase in potential groundwater contamination will also increase risk exposure to major incidents.” [Excerpt | Full document]

An Exxon memo from 1985 discusses MTBE’s “much higher aqueous solubility” than benzene and other gasoline components:

“This can be a factor in instances where underground storage tanks develop a leak which ultimately may find its way to the underground aquifer. When these compounds dissolve in ground water and migrate through the soil matrix they separate into distinct plumes. MTBE creates the most mobile of the common gasoline plumes. MTBE is not a known carcinogen like Benzene however we can be required by public health agencies to remove it based on its taste and odor characteristics.” [View document]