The principles of the E 1903 Standard [1] are used for guidance in many environmental investigations where CERCLA and the Limited Liability Protections (LLPs) under CERCLA are not the determining issues. Throughout this book, we have reviewed many examples where the users' needs extended the Environmental Site Assessment (ESA) investigation of issues beyond the core scope of CERCLA. Various sections of the Standard include reference to issues that are beyond the scope of E 1903. The issues are reviewed and discussed in this chapter.