(a) Where an application for review of a notice of violation or order of cessation is filed by a permittee, DOM as well as any other person granted leave to intervene pursuant to 460:2-1-11 shall file an answer within 20 days of service of a copy of such application.
(b) Where an application for review is filed by a person other than a permittee, the following shall file an answer within 20 days of service of a copy of such application:
(1) DOM;
(2) The permittee; or
(3) Any other person granted leave to intervene pursuant to 460:2-1-11.