Nothing in this act shall be construed as estopping the Commonwealth, a district attorney or solicitor or a municipality from proceeding in courts of law or equity to abate releases forbidden under this act, or to abate nuisances under existing law. It is declared to be the purpose of this act to provide additional and cumulative remedies to control the release of hazardous substances within this Commonwealth. Nothing contained in this act shall abridge or alter rights of action or remedies at law or in equity. No provision of this act, the granting of approval under this act, nor an act done by virtue of this act shall be construed as estopping the Commonwealth, persons or municipalities in the exercise of their rights at law or in equity; from proceeding in courts of law or equity to suppress nuisances or to abate a pollution; or from enforcing common law or statutory rights. No courts of this Commonwealth having jurisdiction to abate public or private nuisances shall be deprived of jurisdiction in an action to abate any private or public nuisance because the nuisance constitutes pollution of air or water or soil.