DES MOINES -- Gasoline is proving expensive for one company in Iowa even before it's pumped into a gas tank.

Attorney general Tom Miller has filed suit against a Wisconsin-based company for environmental violations concerning 61 of its underground storage tanks (USTs) at 17 retail gas stations in nine Iowa cities. The suit focuses on environmental damage from leaks in the tanks.

Miller's suit alleges that Bulk Petroleum Corp. "repeatedly has failed to comply with requirements to prevent corrosion of steel UST systems, failed to prevent and detect releases, failed to report and investigate releases, and failed to maintain UST compliance records."

Leaking underground oil and gasoline storage tanks are one of the more commonly-sued environmental breaches. The day after Miller announced his suit, the federal EPA announced a ruling against Washington, D.C.-based UST owner Samad Corp., also for failing to monitor leaks and prevent corrosion.

Samad paid a $29,000 penalty and corrected all alleged violations arising from problems with three gasoline USTs and one motor oil UST, the EPA announced last week.

The UST leakage problem is particularly acute in New Jersey, which has around 240,000 residential USTs for heating oil, according to the New Jersey Fuel Merchants Association (NJFMA). However, the NJFMA estimates that "less than one percent of all underground tanks nationwide ever experience a release."

The Bulk Petroleum case was referred to Miller by the Iowa Environmental Protection Commission. Breaches are punishable by fines of up to $5,000 per violation per day.