The Attorney General, on request of the Secretary after a finding by the Secretary of destruction, loss, or injury to a System unit resource or a finding that absent the undertaking of a response action, destruction, loss, or injury to a System unit resource would have occurred, may bring a civil action in United States district court against any person or instrumentality that may be liable under section 100722 of this title for response costs and damages. The Secretary shall submit a request for the civil action to the Attorney General whenever a person may be liable or an instrumentality may be liable in rem for those costs and damages under section 100722 of this title.