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swd PROPOSED SCOPE OF SERVICES Task 1 - Baseline Measurements In order to evaluate the effectiveness of ORCO, baseline measurements for the site will need to be collected. Once such critical parameter is the level of dissolved oxygen (DO) in the groundwater. DO is often the rate-limiting component of biodegradation. However, nitrogen and phosphorus can also limit the rate of biodegradation. Further, there must be an adequate microbial population for natural biodegradation to occur. To confirm that adequate indigenous parameters exist at the site, we plan to establish in-situ baseline DO levels for all four wells. Redox, pH, electrical conductivity, temperature, and groundwater elevation readings will also be measured and recorded. In addition to the above in-situ measurements, a groundwater sample will be collected from well MW-2 and analyzed for the following parameters: Heterotrophic Plate Count Phosphate Ammonia Nitrogen �LChemical Oxygen Demand Biological Oxygen Demand The results of the above measurements and analyses will be used to determine whether injection of ORCO by itself will be sufficient, or if addition of nutrients in conjunction with the ORCO will be necessary. The baseline sampling is proposed to be conducted concurrently with a quarterly groundwater sampling episode. Per your request, in addition to analyzing for total petroleum hydrocarbons as gasoline and the aromatic volatile organics "BTEX", the baseline quarterly sampling will include analysis for petroleum oxygenates via EPA method 8260. We concur that this analysis is important in establishing a baseline in which to gauge the effectiveness of ORCO. Task 2 - ORCO/Nutrient Placement The ORCO, and any needed nutrients, will be inserted into monitoring well MW-2 via an ORCO sock. A vertical sock length of approximately 20 feet is proposed. Once inserted, groundwater samples will not be able to be collected from well MW-2 until the sock has been depleted and removed. Further, a sufficient recovery period will likely be necessary following sock removal before representative water samples can be collected from well MW-2. Due to this, the sock will be inserted immediately following a complete quarterly sampling and monitoring episode. JJW GEOSCIENCES Inc.