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HomeMy WebLinkAbout1990-02-13 - AGENDA REPORTS - ELSMERE CYN GROUNDWATER (2)AGENDA REPORT UNFINISHED BUSINESS DATE: February 13, 1990. SUBJECT: ELSMERE CANYON GROUNDWATER RE; DEPARTMENT: Public Works Z,/\_, BACKGROUND LL City Manager Approval Item to be presented by: John E. Medina The proposed Elsmere Canyon Landfill is one of the major issues which faces the Council and City residents. Whether to formulate the City's position on the matter at this time or wait until the Environmental Impact Report is completed is a significant policy decision which could effect future Council actions. One important aspect which has surfaced is what effect the landfill would have on our existing groundwater quality and reserves. Since the residents of the Santa Clarita Valley rely on groundwater pumping to supply nearly half of the expected water demand, this issue is of paramount importance. On January 9, 1990, the Council directed staff to review several reports prepared by Richard C. Slade, consulting groundwater geologist, which has investigated the Santa Clarita Valley's groundwater basin. It was anticipated that review of this information would result in a plan of action which would address groundwater quality vis-a-vis the Elsmere Canyon Landfill. We have reviewed the reports and found that they have a wealth of information dealing with available groundwater reserves and resources but do not address how possible groundwater pollution in Elsmere Canyon would affect the Valley's groundwater quality. There are two typical approaches used in the analysis of the impacts of landfill sitings. Some advantages and disadvantages of each is as follows: 1. City begins review when the Environmental Impact Report (EIR) is completed. 2. Have focused E.I.R. on groundwater only prepared for the City at M/ Advantages •E.I.R. is a significant data resource -Details of siting would be available -Mitigation measures would be indicated -More thorough review can be performed on sue Disadvantages -Short time for review -Many other factors being reviewed at the same time. -Expensive -Duplication of effort which will be found in the Elsmere E.I.R. Agenda Item: Elsmere Canyon Landfill February 13, 1990 Page 2 Although both of these studies will provide data on the environmental impacts and some mitigation measures necessary to ensure the protection of the environment, neither will address the question of what are the hazards to the Santa Clarita Valley's groundwater quality and reserves if the mitigation measures do not function as expected. We feel this is such an important issue that it should be studied separately. We propose that data should be assembled that addresses: • Soil Permeability • Area Geology • Leachate Migration • Natural Purification • Surface Drainage • Listing of Potential Mitigation Measures • Necessary tests and their locations to evaluate the above These are some select items which we would like to pursue in developing a scope of work which will provide the necessary data to address the potential groundwater degradation issue that will not be found in the E.I.R. or a focused E.I.R. The development of the scope of work should provide a more extensive list of required data which we will present to the Council. In addition, we would solicit input and possible funding from local water purveyors who would be affected by the siting of Elsmere Canyon within the Valley. RECOMMENDATION 1. Direct staff to prepare a scope of work for a study on the effects of the siting of Elsmere Canyon Landfill on the Valley's groundwater quality and quantity. 2. Direct staff to report to the Council the range of costs, list of pre -qualified consultants, and time for preparation of the study.