Exxon Mobil Corp. begins its defense this week in a groundwater pollution case in New Hampshire.

The state of New Hampshire claims that Exxon Mobil knew the gasoline additive methyl tertiary butyl ether (MTBE) was contaminating drinking water and did not alert the public. New Hampshire is seeking at least $245 million from the Irving, Texas-based oil company to pay for remediation costs, according to Bloomberg.

Lawyers for Exxon Mobil argue that the federal government required the use of MTBE to replace lead in fuel and that it did not cause any illnesses or injuries.

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"There is simply no MTBE crisis,” Charles Engelmann, an Exxon Mobil spokesman, wrote in an email to Bloomberg. ’’MTBE hasn’t been used in the state since 2005 and there is not a single personal injury being claimed in this lawsuit."

New Hampshire originally filed the lawsuit in 2003 against Exxon Mobil and 25 other oil companies and distributors. The state has received a total of $120 million in settlement money. Exxon Mobil is the only defendant who has not yet settled.

According to the U.S. Environmental Protection Agency, MTBE is not likely to cause adverse health effects at concentrations between 20 and 40 ppb or below.