UPDATE 1-Imperial's Nova Scotia refinery garners interest

* "Multiple parties" interested in bidding

* One of several Atlantic Basin plants facing sale, closure

* Decision expected in early 2013

(Adds background, details)

CALGARY, Alberta, Oct 2 (Reuters) - Imperial Oil Ltd

has buyer interest for its Dartmouth, Nova Scotia, refinery, which the company put on the auction block in May as it struggled with weak Atlantic crude oil basin margins, Imperial's chief executive said on Tuesday.

Imperial, the Canadian affiliate of Exxon Mobil Corp , has said it expects to announce a decision on the plant's fate in the first quarter of 2013.

"We've been through a nonbinding phase, looking to identify potential interested acquiring parties. We've entered a binding phase and we've got multiple parties that are interested," Imperial CEO Bruce March told reporters after giving a speech to a business audience.

He declined to characterize the interested parties, saying it is a private process.

The refinery is among several on both sides of the Atlantic that operators have put up for sale, shut down or threatened to close due to poor economics.

However, buyers have emerged this year, despite the high cost of Brent-linked crude compared with North American oil priced against the cheaper West Texas Intermediate benchmark.

Some are nontraditional, including private equity firm Carlyle Group LP , which formed a joint venture with Sunoco Inc to keep a big Philadelphia plant running, and Delta Air Lines which bought the 185,000 bpd Trainer refinery in Pennsylvania, becoming the first U.S. airline to make such an investment.

Imperial has said that besides a sale, it will also consider turning the Dartmouth refinery into a storage terminal.

(Reporting by Jeffrey Jones; Editing by Marguerita Choy and Bob Burgdorfer)

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