Undertaking remediation efforts in jurisdictions where the regulatory environment and mechanisms are evolving can pose a significant challenge.  Seemingly routine tasks such as disclosure of the release to the regulatory authority, obtaining access agreements, executing the technical work required to evaluate, implement and achieve long term remedial objectives require careful consideration and planning.  In this paper, we outline the intersection of a regulatory and technical strategy employed to address the potential environmental liability associated with a contaminated site located in the State of Sao Paulo, Brazil. The site is a former manufacturing operation located in an industrial area that was developed in the 1960’s. Historic manufacturing operations resulted in a release of chemicals, primarily perchloroethene (PCE), a common industrial solvent that was used in past degreasing operations.  This site presented additional complexity from a technical and regulatory standpoint, such as: (i) being located in an old industrial area; (ii) being contaminated with substances which were also commonly used by several other never-investigated sources in the region; and (iii) belonging to a regulatory environment which encompasses increasingly stringent liabilities with a sometimes confusing and overlapping enforcement scheme. In this example, the State Environmental Regulatory Agency (CETESB) provides regulatory oversight, however, the local municipality, the environmental police, the State district attorney also have a significant role that can influence the scope, cleanup standards, monitoring protocol, and remediation schedule. These competing jurisdictional claims tend to make environmental remediation onerous and expensive.