Mike Bradley says Nova Chemicals is proposing to expand its operations. Sarnia is in competition for the large investment with the American Gulf Coast.
Bradley says Ontario's high electricity rates could be a problem.
"The No. 1 issue that comes to the top of the list on almost every project that might locate here is the cost of power," Bradley said. "Chemical plants, in particular, are heavy users of power so there's a good payback, but we need the province to make sure we're competitive with our American friends."
During a visit to Windsor on Sunday, the premier told CBC News her government knows about Bradley's request and concern.
"Our Ministry of Economic Development, Trade and Employment is engaged in the issue, and we're very eager to keep those jobs and be able to expand jobs in the Sarnia and in the Windsor regions, because we know that these are areas that were hard-hit by the economic downturn," Wynne said.
Bradley expects Nova to make its decision before the end of the year.