MTBE Report: The damage is done |

MTBE Report: The damage is done

by Andy Bourelle

For years Lake Tahoe has been known for its scenic views, beautiful mountains and crystal-clear water. For the past year and a half, however, problems with South Shore’s groundwater increasingly have stolen newspaper headlines and television coverage, taking away from Lake Tahoe’s glory.

The reason is simple – MTBE.

It all started on Sept. 28, 1997. The controversial fuel additive, which at the time most California residents knew little about, was discovered in two of the South Tahoe Public Utility District’s wells. A day later the wells were shut down. A year later, they were destroyed. Since the first discovery, 11 more wells have been shut down – some specifically contaminated, some near a contamination site.

“We were alarmed when we had the first detection,” said Chris Strohm, vice president of STPUD’s Board of Directors. “Then the wells started falling like dominoes. This all happened in a year and a half. It all happened so quickly.”

MTBE – methyl tertiary butyl ether – is a synthetic chemical oxygenate which was first used in American gasoline in the early 1970s. The federal Clean Air Act Amendments of 1990 required the use of oxygenated fuels in many areas of the country, and its use began to grow. California law does not mandate use of MTBE in California, but because of the state’s oxygen-content standards for gasoline, it has become the additive of choice.

MTBE now comprises about 11 percent of the gasoline used in California. Another way of looking at it is this: For every gallon of gas put into someone’s tank, about a pint of it is MTBE.

While MTBE was considered a big factor in cleaning up California’s air, it began causing problems in the groundwater. Although the problems on South Shore are now in the state’s spotlight, Santa Monica faced a huge MTBE problem years before any problem at Tahoe was detected. Now more than 80 percent of Santa Monica’s water – 10 million gallons a day – comes from another source.

“The difference with them is they had another source. We don’t have another source. We don’t even have another aquifer to go to,” Strohm said.

Research is still under way to determine the exact dangers of MTBE. The U.S. Environmental Protection Agency has classified it as a possible cancer-causing agent.

But it’s not as if gasoline doesn’t already contain dangerous chemicals, such as benzene and toluene.

Benzene is a known human carcinogen; toluene causes birth defects.

Even though its potential health effects are not as well documented as other gasoline compounds, MTBE has created huge problems for other reasons. While other gasoline compounds adhere to the soil, traveling very slowly, MTBE permeates the ground at the same rate as water.

In a place like South Shore, where most of the drinking water wells access shallow aquifers, MTBE is even more of a threat.

MTBE also breaks down much slower than other contaminants. It has a half life of 26 years, which means it will exist in groundwater for more than 100 years.

The other problem is the taste and odor. At low levels – sometimes below 5 parts of the additive per billion parts water – MTBE-contaminated water smells and tastes like turpentine. Even if it poses no health risks, it makes water undrinkable.

Prior to September 1997, the district had 34 usable drinking water wells. To date, eight wells are closed because MTBE has been detected in their aquifers. Four have been closed to avoid pulling nearby plumes closer because groundwater – and MTBE – can move up to three times as fast when a nearby well is pumping.

STPUD’s Paloma well – one of the district’s most important wells with the capacity to provide 2,500 gallons per minute – has been operated at half capacity since July 1997 to keep from drawing in a nearby plume of MTBE.

Another of the district’s wells – Tata Lane No. 4 – was closed in July 1998, with MTBE concentrations of 37 parts per billion. An air-stripping tower first installed to remove a different type of contaminant efficiently removed MTBE from the well’s water for months, but traces of the additive began to slip through.

The district’s latest closure happened in January and included what the district described as “mysterious circumstances.” STPUD’s Clement well pumped water that was completely MTBE free, but also used the air stripper the Tata Lane No. 4 well once used. While clean going in, the water coming out of the stripper contained traces of MTBE. For months, however, no MTBE-contaminated water entered or left the stripping tower. The tower pulls in air, and STPUD officials believe the stripper may be bringing in MTBE-contaminated air. Tests have been conducted, but no results have yet been received.

Another surprising circumstance that happened in January involved the district’s recycled water export pipeline. The district exports its recycled wastewater 26 miles out of the Lake Tahoe Basin, where it is stored in Harvey Place, a reservoir in Alpine County. The water is used in the summer to irrigate more than 2,000 acres of ranch land. However, MTBE traces were discovered in Harvey Place.

“(MTBE is) like flypaper or something. You can’t get rid of the stuff,” Strohm said. “It’s so insidious and evasive. It just makes sense to get rid of it immediately.”

Officials believe the reason behind the contamination is the cleanup efforts of some South Shore gas stations. In their cleanup efforts, the stations pump contaminated water out of the ground, treat it with a carbon filtration system and pump the clean water into the sewer system. However, the MTBE can have “breakthroughs” in the filtration system, and MTBE-contaminated water is sometimes released into the sewer accidentally.

Because of the recent problems, STPUD will be more strict in issuing permits to stations that want to release treated water into the sewer.

The Lahontan Regional Water Quality Control Board is looking into whether it has the authority to fine the parties responsible for the breakthroughs. For irresponsible cleanup efforts on the South Shore, Lahontan already has issued several fines, including an $84,000 fine against the Meyers Beacon and a $292,500 fine against South Lake Tahoe’s USA Gas Station.

STPUD may soon have the ability to issue fines. The district’s board of directors in August 1998 adopted a resolution of intent to adopt a Groundwater Management Plan, which could give the board regulatory authority over the groundwater in its district. The plan could be adopted this summer.

Following their August 1998 action, the board members continued their proactive approach to battling MTBE. In November 1998, STPUD filed a multi-million dollar lawsuit against manufacturers, distributors and retailers for the district’s MTBE problems. The suit could take years before it goes to trial.

STPUD’s water system supplies about 30,000 people through about 12,500 connections, and at times, because of tourism, the total population served is as high as 60,000. The district’s customers faced mandatory water-usage restrictions for much of last summer and may have to comply with the same this coming summer.

To date, MTBE-related costs for the district are about $1.5 million.

In addition to making weekly headlines in the Tahoe Daily Tribune, the district’s problems with the additive have drawn national attention. TV stations and newspapers from Reno, Sacramento and the Bay Area often run stories on South Shore’s MTBE problems. Radio shows as far away as Connecticut have reported on the issues. Reporters from the Wall Street Journal and Boston Globe have interviewed STPUD officials.

“I think Lake Tahoe is well known to the United States and the world as a beautiful place to live. We tout our clean air and clean water. We have that national attention already. To have this contaminant MTBE show up and ruin some of the best water in the world, it’s natural for us to become an example for the problem,” Strohm said. “We, unfortunately, are the poster child for banning MTBE. How have we done it specifically? We’ve been very proactive in getting our statement out. Once the word was out, we’ve had people seek us out. We’d rather it was somebody else’s problem, but we tell a compelling story.”

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