Susan Rivera, ACE Limited?s most senior female executive until being pushed out early in the year amid a regulatory probe, is lending a hand to fledgling Bermuda insurance company Quanta Capital Holdings Ltd.

A Quanta spokesperson confirmed Mrs. Rivera is consulting for the company. It is understood she has been engaged by Quanta for several months already, regularly working out of the company?s New York office. She was also in Bermuda last week, where Quanta is based, on company business.

?We are pleased with the work product and value she has as a consultant,? the spokesperson said. She declined to say what type of work Mrs. Rivera is doing, saying it was not the company?s policy to comment on consulting work.

Quanta is currently under a ratings watch by A.M. Best, one of the most widely followed insurance ratings firms, because of capital adequacy concerns stemming from large catastrophe losses the company expects to see from unprecedented hurricane activity. Because of the storm losses, its shares have also taken a battering in recent months.

Mrs. Rivera resurfaced at Quanta months after her January resignation from ACE, where she came under investigation as part of a probe led by New York Attorney General Eliot Spitzer into allegations of illegal bid rigging between insurance broker Marsh & McLennan Cos. and several insurers, including ACE. In January, Marsh settled charges brought in a lawsuit by Mr. Spitzer, establishing an $850 million fund to compensate affected US customers. Eight Marsh employees were last month indicted on charges related to the matter.

Mrs. Rivera has not been accused of any wrong, under the ongoing investigation. Mr. Spitzer?s office did not yesterday return a call asking if she has been cleared, or remains under investigation.

Her New York lawyer, Barry Ostrager, also did not return a call for comment. Several ACE employees who worked under Mrs. Rivera were fired in connection with the matter.

An e-mail cited in Mr. Spitzer?s suit against Marsh, alleged that Mrs. Rivera had known prior to the investigation that ACE?s casualty risk unit, which fell under her watch, was being pressured to illegally rig bids. And later, another broker, Willis, revealed in its settlement with Mr. Spitzer, that Mrs. Rivera allegedly approved an advance payment of $500,000 from ACE to Willis in exchange for a promise of increased business the next year.

At Quanta, Mrs. Rivera is working closely with a former colleague. Chief executive Tobey Russ and Mrs. Rivera previously worked together at American International Group Inc., where both held senior management positions in AIG?s Risk Finance unit.

Mrs. Rivera left AIG in 2002, joining ACE, a company that has attracted a steady flow of talent away from AIG through the years, including its present chairman Brian Duperreault and chief executive Evan Greenberg.

Mr. Russ left AIG in 2000 to join Chubb Financial Solutions. In 2003, he joined Quanta, as it was being formed, largely staffing the operation with former Chubb employees, as well as employees recruited from CNA Financial Corp. The company also has a large number of staff that joined through Quanta?s acquisition of Environmental Strategies Corporation.

Mrs. Rivera was a rising star at ACE, rapidly ascending the ranks to be named president and chief executive of ACE USA. Through that role, and other senior positions, she was given control of a large portion of the company?s North American operations. ACE derives about half of its earnings and revenue from sales in the US market.

Quanta, a global reinsurer, is a much smaller outfit than either ACE or AIG, where Mrs. Rivera got her career start. At the end of June, Quanta had $437 million in shareholders? equity, making it one of the smallest Bermuda-based global insurance companies.

The company, which recently stopped selling some policies because of its storm losses, said it is looking at ways of raising additional capital. It expects to have more details by the time it releases its third-quarter earnings at the end of the month. In total, Quanta estimated losses in the region of $50 million from hurricanes Katrina and Rita, which is on par with losses it sustained from hurricane activity in 2004. It has not made any statement on losses from Hurricane Wilma, which hit parts of the Caribbean, Mexico and Florida earlier this week. Quanta shares, which trade on the Nasdaq, have lost significant value since investors became concerned over storm losses after Hurricane Katrina hit on August 29.

The stock yesterday closed down one cent at $4.34. The shares have traded as high as $10.25 in the last year, and as low as $4.30.