(a) Except as provided in subsection (c), any person having an interest which is or may be adversely affected may commence a civil action on his own behalf to compel compliance with this act or any rule, regulation, order or permit issued pursuant to this act against the department where there is alleged a failure of the department to perform any act which is not discretionary with the department or against any other person who is alleged to be in violation of any provision of this act or any rule, regulation, order or permit issued pursuant to this act. Any other provision of law to the contrary notwithstanding, the courts of common pleas shall have jurisdiction of such actions, and venue in such actions shall be as set forth in the Rules of Civil Procedure concerning actions in assumpsit.

(b) Whenever any person presents information to the department which gives the department reason to believe that any person is in violation of any requirement of this act or any condition of any permit issued hereunder or of the acts enumerated in section 4(a)(2) H¹ or any condition or any permit issued thereunder, the department shall immediately order inspection of the operation at which the alleged violation is occurring, and the department shall notify the person presenting such information and such person shall be allowed to accompany the inspector during the inspection.

(c) No action pursuant to this section may be commenced prior to sixty (60) days after the plaintiff has given notice in writing of the violation to the department and to any alleged violator, nor may such action be commenced if the department has commenced and is diligently prosecuting a civil action in a court of the United States or a state to require compliance with this act or any rule, regulation, order or permit issued pursuant to this act, but any such action in a court of the United States or of the Commonwealth any person may intervene as a matter of right.

(d) The provisions of subsection (c) to the contrary notwithstanding, any action pursuant to this section may be initiated immediately upon written notification to the department in the case where the violation or order complained of constitutes an imminent threat to the health or safety of the plaintiff or would immediately affect a legal interest of the plaintiff.

(e) The court, in issuing any final order in any action brought pursuant to this section, may award costs of litigation (including attorney and expert witness fees) to any party, whenever the court determines such award is appropriate. The court may, if a temporary restraining order or preliminary injunction is sought, require the filing of a bond or equivalent security in accord with the Rules of Civil Procedure.