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ATTACHMENT 5 City of Lodi White Slough Water Pollution Control Facility Groundwater Monitoring Workplan Monitoring Well Specifications January 12, 2001 Monitoring wells shall be constructed in accordance with the Well Standards issued by the San Joaquin County Public Health Services - Environmental Health Division and the California Well Standards issued by the California Department of Water Resources as Bulletins 74-81 and 74-90. Monitoring wells shall be constructed with 2-inch nominal diameter, schedule 40, polyvinyl chloride (PVC) blank and slotted casing. Casing shall be of the flush threaded type. No solvent welded casing shall be used. The slotted casing shall extend three feet, minimum, above the highest seasonal water level anticipated. The casing shall be provided with a plug or seal at the bottom. Well boreholes shall be constructed with hollow-stem augers of sufficient inside diameter to permit insertion of the casing through the auger. Gravel pack material shall be clean and free of organic material. The gravel pack shall extend a minimum of 1 foot above the top of the slotted casing. A minimum of 2 feet of bentonite shall be placed above the gravel pack to form a seal above the saturated zone. The remaining annular space shall be filled with a mixture of sand and bentonite or neat cement. The sand shall be clean and free of organic material. The mixture shall contain a minimum of 30 percent granular bentonite. For aboveground completions, the well casing shall extend 28 inches above the top surface of the concrete base. The monitoring well shall be protected with a minimum 8- inch diameter, schedule 40, steel pipe set in concrete. The steel pipe enclosure shall be primed and painted orange. The concrete shall extend a minimum of 18 inches below the finished grade. The steel pipe enclosure shall be provided with a hinged cover and hasp suitable for locking. The bottom of the hinged cover shall be 2 inches above the top of the well casing. A drain hole shall be provided in the steel pipe to permit draining of the annular space above the concrete. The well shall be protected with three bollards. The steel bollards shall be primed and painted orange and filled with concrete. The bollards shall be set in concrete. The concrete shall extend 18 inches below finished grade. For subsurface completions, the top of the casing shall be protected with an Emco Wheaton A722 Monitoring Well Manhole with locking cap and collar. Page 1 of 1