Gendell, general partner of Tontine Capital Partner LP, said in a letter Wednesday to Duratek Chief Executive Officer Robert Prince that the company was worth more than the $22 a share accepted by Duratek management. The letter was disclosed by Greenwich, Conn.-based Tontine in a government filing.

Duratek said Tuesday it would seek stockholder approval in the second quarter.

Gendell said Tontine owns 1.917 million Duratek shares, or 12.9 percent of the company, which handles hazardous waste. The stock has traded as high as $28 a share a year ago, so the EnergySolutions offer ''does not adequately reflect the fair value of the company,'' Gendell said.

EnergySolutions on Tuesday agreed to pay $22 a share, or a 26 percent premium over Duratek's closing price on Feb. 6. The acquisition, which includes $51 million of assumed debt, will be funded partly by loans from Citigroup Inc. and other banks.

EnergySolutions spokesman Mark Walker said Wednesday his company had no comment on the development.

EnergySolutions is owned by a private investor group led by Lindsay Goldberg & Bessemer, Peterson Partners and Creamer Investments. Earlier this month, it agreed to spend $90 million on a U.S. unit from British Nuclear Fuels that decommissions nuclear power plants.

Shares of Columbia, Md.-based Duratek rose 98 cents to $22.27 at the close of composite trading on the New York Stock Exchange.

Bear Stearns & Co. advised Duratek. Citigroup Global Markets Inc., J.P. Morgan Securities Inc. and Calyon Securities (USA) Inc. advised EnergySolutions. Hogan & Hartson LLP is Duratek's lawyer. EnergySolutions used Weil, Gotshal & Manges LLP.