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1. GENERAL INFORMATION The City of Lathrop's Consolidated Treatment Facility(CTF) treats and disposes domestic wastewater generated within the City of Lathrop. On February 5, 2015,the Regional Water Quality Control Board approved new Waste Discharge Requirements (WDRs) (Order No. R5-2015-2006). As required by section H. Provisions 1. (c) of the City's new WDRs,this Monitoring Well Condition Survey Report and Destruction Plan describes the current condition of accessible monitoring wells identified in Finding 43.Additionally,this report tabulates ownership information for each well and describes the City's right to access these wells. The Monitoring Well Abandonment Plan provided as Appendix A describes the proposed procedures to abandon wells identified in the WDRs,and additional wells identified as damaged or dry during site visits conducted during September and October 2015.An Inspection and Maintenance Plan (provided as Appendix B) describes procedures to ensure monitoring wells are properly maintained for use.The City will move forward on the improvements and abandonments identified for wells located on City-owned parcels or within the City right-of-way. However,for wells that are located on private property,the City will have to first share the well condition assessment then work with the land owner to prepare a course of action. 2. CONDITION OF MONITORING WELLS In October 2015, FGL Environmental personnel visited the 33 monitoring wells that comprise the active monitoring well network to conduct water level measurements and well-water sampling as required under Order No. 115-2015-2006. HydroFocus, Inc.personnel determined site conditions for accessible monitoring wells identified in Finding 43 of the WDRs that are not part of the network(see Figure 1 for well locations). HydroFocus'site visits were conducted during the period September 29 through October 22, 2015, and included visible well inspections,measuring the depth to water and to the well bottom,and purging five casing-volumes from the well using a pump to confirm functionality. Field parameters (temperature,pH,electrical conductivity,and dissolved oxygen) were measured in the purge-water using a YSI Model 650 Pro-Plus multimeter and flow cell. Table 1 lists the current status and ownership of the monitoring wells.The existing monitoring wells associated with the Crossroads Wastewater Treatment Facility,which are regulated by separate WDRs (WDRs 5-01-251),and three monitoring wells found during the site visit at the Crossroads facility and SLSP parcels are also included in Table 1. Permitting is currently underway to consolidate the City of Lathrop's wastewater treatment facilities in which Crossroads Wastewater Treatment Facility will be decommissioned and all wastewater will be diverted through the Consolidated Treatment Facility.The Crossroads monitoring well network is included because it will most likely be incorporated into the CTF monitoring network once permitting has been finalized,which is anticipated in April 2016. Approximately 40-percent of the monitoring wells are located in street right-of-ways or on property owned by the City of Lathrop and therefore are accessible to the City. For the remaining Groundwater Monitoring Well Condition Survey 2 HydroFocus, Inc. Report and Destruction Plan