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STANDARD OPERATING PROCEDURES FIELD SAMPLING PROTOCOL 2004 The following standard operating procedures (SOP'S) discussed are all part of the quality assurance and quality control measures implemented by Del-Tech. Our goal is to provide the highest level of accurate and representative sample collection, field monitoring and field analysis possible. All of the monitoring and sample collection is completed in accordance to the standard levels of EPA Standard 846, CAL EPA standards, California Department of Health Services. Monitoring Well (purging & sampling) Initially, upon arriving at the site all monitoring wells are located and dependent on the prior monitoring measurements the up gradient well is located. Standard operating procedures to minimize cross contamination, are to work from the cleanest potential monitoring point progressively to the highest possible contaminated location(s). Then site safety procedures are implemented. All the monitoring well exteriors will be cleaned prior to opening and orange safety cones or barricades will be placed around each well for traffic control. Next all of the monitoring well boxes are opened and unlocked. When requested, at this immediate point in time, the well head is monitored for the presence of volatile organics with a hand held Thermodine 580B Photo Ionization Detector. Upon completing the gas screening of the well casing, the well cap is placed back on the well head very loosely to allow the static water level to stabilize. We then proceed to the rest of the wells Additionally, all well boxes that have any standing water inside of them will be inspected to determine if any surface water has been leaking into the monitoring well. We then will use a hand pump and pump out the water prior to opening the well. Now that the well head screening has been completed, the opened wells have allowed the water within the casing time to stabilize to the surface atmospheric pressure. i.e. (We have discovered that measuring wells immediately after opening will not give accurate or representative measurements. By allowing the wells to breath the measured depth to water (DTW) is not during a stabilization transition time when the water is actually moving up or down immediately after the well has been unsealed. This breathing time also allows any trapped gas to expel and reduce the chance of any exposure to the sampling technician. Next, all the monitoring wells are measured to one hundredth of an inch, for the static standing depth to water (DTW) with a Solmist depth to water meter and then the total depth (TD) is recorded. Decontamination is completed at each location to the measuring tape. A spray bottle with alconox soap and a spray bottle with clean rinse water is used to complete this task. If the measuring tape appears to be very contaminated then we will return to the decontamination trailer and scrub the Del -Tech Geotechnical Support Standard Operating Procedures / Groundwater Monitoring 2004