The five year presumption of adequacy afforded a Master EIR can be periodically renewed as provided in Guidelines Section 15179. This renewal may take either of two forms: (1) a finding that no substantial changes have occurred with respect to the circumstances under which the Master EIR was certified or that no new information has become available since certification of the Master EIR; or (2) preparation and certification of a subsequent or supplemental EIR that is incorporated into the previously certified MEIR or references any deletions, additions or other modifications to the MEIR. The findings under the first option should hew closely to CEQA Guidelines Section 15162 which describes the situations under which a subsequent or supplemental EIR need not be prepared.
If, during the five year period (and, presumably, during renewed periods), projects are approved which were not identified in the certified Master EIR and which may affect the adequacy of the Master EIR relative to subsequent projects, then the Lead Agency must review the adequacy of the Master EIR and make the findings described above before it can apply the Master EIR to subsequent projects.
The resulting updated Master EIR can then be applied to the review of
subsequent projects that are described as being within its scope.