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September 29,2014 Monitoring Well Abandonment and Installation Workplan Filter pack material will be placed in the well boring to a depth of 1-foot above the top of the well screen using a tremie pipe or equivalent.The filter pack depth will be checked,and the volume of filter pack material considered for verifying that no bridging of filter-pack materials occurred.Each well will be gently surged during filter-pack installation (i.e., surging will occur after the filter-pack is poured into the annulus between the casing and borehole wall,but prior to the installation of the transition and sanitary seals). 3.3. Transition and Sanitary Seals The remaining annular space will be filled with a transition seal (minimum thickness of 2 feet)set on top of the filter pack,followed by a neat-cement based sanitary seal to land surface (minimum thickness of 10 feet).Bentonite or other approved material will be used for the transition seal.For depths greater than 30 feet,and where water is present in the borehole,the material will be installed by use of a tremie pipe or equivalent.Where bentonite exists in the borehole in dry form,potable water will be added and sufficient time allowed for the bentonite to properly hydrate before placement of the sanitary seal. The sanitary seal will be placed within the annular space between the top of the transition seal to land surface.Sealing material will be selected based on required structural,handling, and sealing properties and the chemical environment into which it is placed.Drilling fluid or cuttings from the borehole will not be used as the sealing material.All water used for sealing mixtures shall be potable. 3.4. Surface Seals Surface features will serve to prevent physical damage;prevent the entrance of surface water,pollutants,and contaminants; and prevent unauthorized access.The top of each monitoring well will be protected by a locking cover or equivalent level of protection to prevent unauthorized access.The top of the well casing will be sealed with a removable plug that provides a means to secure and lock the well. For KMW-9,the sealed well-casing will be set below grade in a traffic-rated vault box with lid (below ground completion).For KMW-8,the well casing will be housed in a locking monument style well cover(above ground completion)that extends at least 2 feet above land surface,surrounded by three protective bollards. 4. Well Development The driller will develop the well using surging,bailing,and pumping techniques.Well development will be performed with care so as to prevent damage to the well and any strata surrounding the well that serve to restrict the movement of poor quality water.A pump will be utilized to further develop the wells no less than 12 hours after sanitary seal placement, per SJCEHD Well Standards.Well development will continue until the flowing water is visually clear(1.5 hour per well minimum development time)and pH,conductivity and temperature of purge water stabilize within plus or minus 10%; the volume of purge water shall be recorded on a standard well development form. HydroFocus, Inc. __ 9