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Field Practices and Procedures Page 5 than two wells will be located on site. Monitoring well elevations will be surveyed by a California licensed surveyor to the nearest 0.01-foot relative to mean sea level (MSL). Horizontal coordinates of the wells will be measured at the same time. Exploratory boring logs and well construction details will be prepared for the final written report. Monitoring Well Development Methods Monitoring well development is conducted to ensure removal of fine-grained sediments from the vicinity of the well screen. This allows the water to flow freely from the formation into the well, and also reduces the turbidity of the water during sampling. The most common well development methods are: surging,jetting, overpumping, and bailing. Well development at the site will be conducted by surging and bailing, followed by groundwater pumping, at a minimum of 72 hours following installation. Surging involves raising and lowering a surge block or surge plunger inside the well. The resulting surging motion forces water into the formation and loosens sediment, pulled from the formation into the well. Occasionally, sediments must be removed from the well with a sand bailer to prevent sand locking of the surge block. The process is repeated until the well is sediment free. Bailing includes the use of a simple manually operated check-valve bailer to remove water from the well. The bailing method, like other methods, should be repeated until sediment free water is produced. Bailing is often the method of choice in a shallow well or well that recharges slowly. Development Prior to developing, the initial pH, temperature, turbidity, and specific conductivity of the water will be recorded in a purge log. As development of the monitoring well progresses, the water quality parameters (pH, temperature, turbidity, and specific conductivity) will be monitored periodically. Development of the monitoring well will continue until at least 10 well casing volumes have been removed and the water quality parameters stabilize, or until the water has a turbidity of less than 50 nephelometric turbidity units (NTUs). All water produced by development of the monitoring wells will be contained in DOT-approved 55-gallon steel drums. The drums will be appropriately labeled and stored at the Site pending proper disposal. A licensed contractor will transport the soil and wastewater to an appropriate facility (based on analytical results) for disposal.