The Reagan administration is considering whether to rescind some of former president Carter's parting-shot executive orders, including one that implements the $1.2 billion so-called superfund program to clean up toxic dumps and spills.

The mere rumor of action to stop the hightly controversial program from going into effect has caused alarm at the Environmental Protection Agency, which has a special task force all geared up to run it, and consternation in at least two congressional offices. Meanwhile, the White House says no policy shifts are at stake.

President Carter signed the superfund executive order the day before he left office, giving EPA and the Coast Guard authority to run the fund and clean up abandoned dumps and toxic spills that EPA would designate. The fund needs an executive order, unlike most legislation, for technical reasons related to the history of water pollution control.

Rep. James Florio (D-N.J.), sponsor of the fund bill, wrote Reagan to "respectfully request that you consider keeping this order in place." All existing executive orders are subject to revocation at the new president's discretion and fund supporters are mindful that Office of Management and Budget Director David A. Stockman was one of the superfund's opponents last year when he was a congressman.

Frederick Khedouri, OMB associate director for natural resources, confirmed that "active reconsideration" is under way. "There is some desire to see if we might want to assign responsibilities in a different way, not to change the legislation or its purpose, but more in the line of administrative shifts," he said. "There's no reason for anyone to get exicited. There's no implication for policy."

Robert Roland, president of the Chemical Manufacturers Association, said no one in the administration had asked his opinion but he thought rescission of the order and any reassignment of functions would be a bad idea. "It would delay things . . . it wouldn't be helpful either for the chemical industry or the country," he said.