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Like Oil and Water

As Congress Considers Legal Immunity for Oil Companies More Communities Go To Court Over MTBE Pollution

April 5, 2005

Like Oil and Water: MTBE Contamination By State

MTBE contamination is soaring

Although the use of MTBE in gasoline is rapidly declining, detections of MTBE in water supplies are soaring. The number of water systems reporting MTBE contamination in tap water supplies increased more than 15-fold between 1996 and 2004, from 137 to 1,861, and the number of states reporting problems more than doubled, from 11 to 29, according to EWG Action Fund's analysis of state water testing data. These figures are not necessarily systems whose customers are currently drinking MTBE in their tap water, but those where it has been detected somewhere in the system. The total number of contaminated systems includes private water supplies that may serve only a single customer, but more than 60 percent (about 1,100 systems) supply drinking water to cities, counties, rural communities and schools.

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. MTBE contamination as low as two parts per billion — two drops in an Olympic-sized swimming pool — can produce a harsh chemical odor and taste that can cause tap water to be undrinkable. To cope with the problem, water utilities must 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 American Water Works Association, representing 4,700 U.S. water systems, estimates nationwide MTBE cleanup and water replacement costs at $29 billion — and rising with each new detection.

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 32 million people in California, about 4.7 million in New Jersey, about 2.2 million in Massachusetts and 1 million in Texas.

MTBE Has Been Found in Tap Water in At Least 29 States

* Important Note: Many states do not keep records on their MTBE contamination. This list only reflects states that did report MTBE contamination data.


State Number of
Systems Affected
Total 1,860 21,532,000 to
Alaska 1 36,000
Alabama 9 298,000
Arkansas 110 593,000
California 144 32,087,000
Delaware 15 83,000
Florida 13 857,000
Iowa 3 3,000
Illinois 44 354,000
Indiana 14 193,000
Massachusetts 221 2,243,000
Maryland 116 196,000
Maine 16 58,000
Michigan 14 57,000
Minnesota 27 224,000
Missouri 13 17,000
Nebraska 8 11,000
New Hampshire 280 409,000
New Jersey 430 4,791,000
New Mexico 5 39,000
Nevada 4 231,000
New York 170 453,000
Ohio 5 9,000
Oklahoma 13 6,000
Pennsylvania 47 981,000
Rhode Island 28 83,000
South Carolina 20 63,000
Texas 46 1,080,000
Virginia 15 12,000
Wisconsin 29 234,000


* Low end estimate excludes systems serving over 1 million people. In large systems MTBE contamination typically affects only a portion of the population.

Source: Environmental Working Group. Data on MTBE lawsuits obtained from court records and law firms representing communities. Information on MTBE contamination is derived from data obtained from state agencies under the Federal Freedom of Information Act or state public records laws. Data were unavailable for some states; other states reported no MTBE detections. Some states currently do not require reporting of MTBE detections.

Important Note: A reported detection of MTBE does not mean the contaminant was found at any level in finished drinking water that the water system delivered to consumers. Some results reflect tests conducted on a water source, others may reflect results from finished tap water. MTBE contamination as low as 2 parts per billion produces a harsh chemical odor that renders the tap water undrinkable. For that reason, in the vast majority of the affected communities water utilities have taken steps to protect consumers, often with costly remedial action, as soon as MTBE is detected and before water is delivered. Water utilities either blend contaminated water with clean sources to dilute the MTBE in finished water, install costly systems to remove the chemical, or abandon tainted wells and shift to clean sources. Community water suppliers would be unable to recover the cost of these remedies from MTBE manufacturers under the liability shield Republican leaders have proposed to include in pending national energy legislation.

Data are primarily for community water systems. Comparable data are not available for MTBE contamination of the majority of private wells.

In some communities, 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. State water testing 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 four years. Water systems nationwide are wrapping up 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. The prospect that the MTBE contamination crisis has yet to peak makes the scheme to shield polluters from liability all the more troubling.

Also rising rapidly are lawsuits against the oil companies by communities whose water is contaminated with MTBE. Since September 2003, at least 141 water systems in 16 states have filed suits arguing that MTBE is a defective product, and that refiners knew that it would contaminate groundwater before they began adding it to gasoline but failed to warn consumers. In 2002 that argument, outlined in devastating detail in industry documents, convinced a jury to find Shell, Texaco and four other companies liable for contaminating drinking water supplies in South Lake Tahoe, Calif., forcing a $60 million settlement for cleanup. In 2003, Shell, Exxon, ChevronTexaco and 15 other companies settled a contamination lawsuit brought by Santa Monica, Calif., by agreeing to spend an estimated $200 million on a filtration system to remove MTBE from the city's water supplies.

The success of those lawsuits in holding the oil companies responsible for MTBE contamination sparked the first attempt in 2003 by the industry and its political allies to make it impossible for communities to sue on defective product grounds. In turn, the push for the waiver set off a rush to file lawsuits by communities with contamination. Of the 150-plus cases now in court, at least 141 were filed after September 2003 and would be thrown out by the retroactive provision of the DeLay-Barton bill. If MTBE makers are given immunity from defective product lawsuits, the burden of cleanup will fall to individual gas station owners, most of whom lack the kind of money it would take, and ultimately to the taxpayers.

In the House, 21 Republicans and five Democrats who voted for the energy bill and MTBE liability waiver now are faced with the prospect, if they again support it, of throwing out a total of 38 lawsuits filed by community water systems in the districts they represent. Three Members are from New Jersey, which has a total of 430 water systems where MTBE has been detected — far more systems than in any other state, supplying drinking water to 4.7 million Garden State residents. Eleven are from California, where MTBE has been found in 144 water systems serving more than 32 million people — almost 90 percent of the state's population.

An additional 81 House members — 74 Republicans and 9 Democrats — who supported the energy bill and liability waiver represent districts where MTBE has been detected in the water supply, but lawsuits have not been filed. Seven are from California, representing districts where 22 water systems have detected MTBE. Thirteen, including DeLay and Barton, are from Texas; in their districts are 29 water systems with MTBE contamination. One House member who voted yes in 2003 (Arkansas Democrat Mike Ross) has 50 water systems in his district with contamination. Another (Maryland Republican Roscoe G. Bartlett) has 50.

84 House Members Who Voted To Protect Oil Companies From Litigation in 2003 Also Represent Communities With MTBE In Their Drinking Water

  Member State/District Systems with contamination Vote on Energy Bill
final passage
in 2003
1 Akin, W. Todd MO-2nd 2 Yea
2 Baca, Joe CA-43rd 2 Yea
3 Bachus, Spencer AL-6th 2 Yea
4 Barrett, J. Gresham SC-3rd 4 Yea
5 Bartlett, Roscoe G. MD-6th 50 Yea
6 Barton, Joe TX-6th 1 Yea
7 Berry, Marion AR-1st 28 Yea
8 Biggert, Judy IL-13th 1 Yea
9 Blunt, Roy MO-7th 2 Yea
10 Bonilla, Henry TX-23rd 3 Yea
11 Bonner, Jo AL-1st 5 Yea
12 Boozman, John AR-3rd 18 Yea
13 Brady, Kevin TX-8th 1 Yea
14 Brown, Henry E. Jr. SC-1st 1 Yea
15 Burgess, Michael C. TX-26th 1 Yea
16 Buyer, Steve IN-4th 3 Yea
17 Camp, Dave MI-4th 3 Yea
18 Cantor, Eric VA-7th 3 Yea
19 Carter, John R. TX-31st 2 Yea
20 Cole, Tom OK-4th 4 Yea
21 Culberson, John Abney TX-7th 2 Yea
22 Cunningham, Randy ``Duke'' CA-50th 1 Yea
23 Davis, Jo Ann VA-1st 1 Yea
24 DeLay, Tom TX-22nd 1 Yea
25 Dreier, David CA-26th 6 Yea
26 Emerson, Jo Ann MO-8th 4 Yea
27 Evans, Lane IL-17th 6 Yea
28 Everett, Terry AL-2nd 1 Yea
29 Feeney, Tom FL-24th 1 Yea
30 Foley, Mark FL-16th 3 Yea
31 Gerlach, Jim PA-6th 11 Yea
32 Gibbons, Jim NV-2nd 3 Yea
33 Goode, Virgil H. Jr. VA-5th 2 Yea
34 Goodlatte, Bob VA-6th 2 Yea
35 Graves, Sam MO-6th 2 Yea
36 Green, Gene TX-29th 2 Yea
37 Gutknecht, Gil MN-1st 4 Yea
38 Hall, Ralph M. TX-4th 4 Yea
39 Harris, Katherine FL-13th 1 Yea
40 Hastert, J. Dennis IL-14th 5 Yea
41 Hoekstra, Peter MI-2nd 1 Yea
42 Holden, Tim PA-17th 3 Yea
43 Hunter, Duncan CA-52nd 2 Yea
44 Hyde, Henry J. IL-6th 1 Yea
45 Issa, Darrell E. CA-49th 4 Yea
46 Istook, Ernest J. Jr. OK-5th 4 Yea
47 Johnson, Timothy V. IL-15th 2 Yea
48 Kennedy, Mark R. MN-6th 5 Yea
49 Kline, John MN-2nd 7 Yea
50 LaHood, Ray IL-18th 7 Yea
51 Lewis, Jerry CA-41st 3 Yea
52 Lucas, Frank D. OK-3rd 5 Yea
53 McCotter, Thaddeus G. MI-11th 1 Yea
54 McHugh, John M. NY-23rd 14 Yea
55 Manzullo, Donald A. IL-16th 8 Yea
56 Neugebauer, Randy TX-19th 2 Yea
57 Ney, Robert W. OH-18th 2 Yea
58 Osborne, Tom NE-3rd 4 Yea
59 Pearce, Stevan NM-2nd 2 Yea
60 Pence, Mike IN-6th 1 Yea
61 Peterson, Collin C. MN-7th 3 Yea
62 Platts, Todd Russell PA-19th 4 Yea
63 Pombo, Richard W. CA-11th 2 Yea
64 Radanovich, George CA-19th 4 Yea
65 Ramstad, Jim MN-3rd 2 Yea
66 Rogers, Mike MI-8th 3 Yea
67 Rogers, Mike AL-3rd 1 Yea
68 Ross, Mike AR-4th 50 Yea
69 Sessions, Pete TX-32nd 1 Yea
70 Shaw, E. Clay Jr. FL-22nd 1 Yea
71 Sherwood, Don PA-10th 7 Yea
72 Shimkus, John IL-19th 8 Yea
73 Skelton, Ike MO-4th 1 Yea
74 Smith, Lamar S. TX-21st 12 Yea
75 Terry, Lee NE-2nd 1 Yea
76 Thornberry, Mac TX-13th 1 Yea
77 Upton, Fred MI-6th 2 Yea
78 Weldon, Curt PA-7th 5 Yea
79 Weller, Jerry IL-11th 5 Yea
80 Wilson, Heather NM-1st 1 Yea
81 Wilson, Joe SC-2nd 7 Yea
82 Wynn, Albert Russell MD-4th 2 Yea
83 Young, C. W. Bill FL-10th 1 Yea
84 Young, Don AK-At Large 1 Yea


Source: Environmental Working Group. Data on MTBE lawsuits obtained from court records and law firms representing communities. Information on MTBE contamination is derived from data obtained from state agencies under the Federal Freedom of Information Act or state public records laws. Data were unavailable for some states; other states reported no MTBE detections. Some states currently do not require reporting of MTBE detections.