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City of Roseville Proposal BL-08-02387G January 26, 2010 Page 2 We will stake the proposed water main, sanitary sewer, and boring locations. Further, we will determine ground-surface elevations at those boring locations and coordinate the clearing of public utilities. The borings will be located using Global Positioning System (GPS) technology and the State of Minnesota GPS network. The boring locations may be altered by our field crew from those proposed to facilitate accessibility or to avoid existing utilities (if any). Minnesota Department of Health (MDH) regulations require us to grout any boring that encounters a water-bearing stratum and either penetrates a confining layer or extend deeper than 25 feet. For the purposes of this proposal, it is assumed that all 6 borings will be grouted. Soil Screening A Braun Intertec environmental technician will be at the Site during the soil borings to monitor and log the subsurface materials encountered at each soil boring location. Soil discoloration and odors will be documented if detected. In addition, soil samples will be screened for the presence of organic vapors with a PID using both direct readings from each sample and the headspace method of analysis recommended in "Soil Sample Collection and Analysis Procedures," Minnesota Pollution Control Agency (MPCA) Petroleum Remediation Program Guidance Document 4-04, Section 1. Soil Sampling and Laboratory Analyses In accordance with direction from the MPCA, three soil samples will be collected from each of the six soil borings (18 soil samples total) for laboratory chemical analyses at the Braun Intertec laboratory. The soil samples will be collected from the depth intervals displaying visual or olfactory indications of contamination, or the highest field-screened organic vapor concentration. The soil samples will be analyzed for the presence and concentrations of the following parameters: . Diesel-range organics (DRO) . Gasoline-range organics (GRO) . Volatile organic compounds (VOCs) The soil samples will be transported under refrigerated conditions and accompanied by Braun Intertec chain-of-custody records. All analyses will be performed within U.S. EPA holding times. Groundwater Sampling and Laboratory Analysis Temporary wells will be installed in all six of the proposed soil borings to obtain perched groundwater samples (if encountered). If present, perched groundwater samples will be collected from each of the six temporary wells and analyzed for the presence and concentrations of the same parameters as the soil samples, including DRO, GRO, and VOCs. Subsurface Evaluation Results and Reporting Verbal results of the subsurface evaluation will be provided to you as they become available to us. Following receipt of the analytical testing results, Braun Intertec will summarize the results of the subsurface evaluation into a report. The following items will be included in the summary report: eRauN INTERTEC