The department, by and through the commissioner, shall be exempt for activities conducted pursuant to subdivision five of section 27-1411 of this title and shall be authorized to exempt a person from the requirement to obtain any state or local permit or other authorization for any activity needed to implement a program for the investigation and/or remediation of contamination at or emanating from a brownfield site; provided that the activity is conducted in a manner which satisfies all substantive technical requirements applicable to like activity conducted pursuant to a permit.