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City of Ramsey Project B1700969 March XX, 2017 Page 8 F. Investigation Results F.1. Geologic Conditions Soil boring logs with descriptions of the various soil strata encountered during the soil boring operations and water level information are contained in Appendix A. The depths shown as changes between the soil types are approximate. The actual changes may be transitional, and the transition depths are likely to be horizontally variable. All soil borings encountered sand from the surface to the terminal depth of the boring. Groundwater was encountered in borings S-1, S-4, S-6, S-8, and S-9 at depths ranging from 20.49 to 27.36 feet bgs. F.2. Field Screening Soil recovered from the soil borings was screened by the field technician for evidence of contamination, including odors, staining, and the presence of debris. No odors, staining, or debris were observed in the soils recovered from any of the nine borings, with the exception of concrete debris observed in borings S- 3, S-4, S-6, and a piece of coal in boring S-3. Organic vapor/PID readings were recorded for soil samples collected from each borings. Observed organic vapor concentrations ranged from 0.0 to 1.4 parts per million (ppm), which are considered to be general background readings. Soil screening PID results are included on the boring logs in Appendix A. F.3. Soil Analytical Results A summary of the soil analytical results is provided in Table 1. The complete laboratory reports with chain -of -custody forms are included in Appendix D. The soil analytical results can be compared with the Soil Reference Values (SRVs) and Screening Soil Leaching Values (SLVs) which are also listed on Table 1. SRVs and SLVs are allowable risk -based contaminant concentrations derived by the Minnesota Pollution Control Agency (MPCA) using risk assessment methodology, modeling, and risk management policy to guide investigation and cleanup actions. SRVs relate to direct -contact exposure scenarios and SLVs relate to potential leaching of contaminants to groundwater. Concentrations of contaminants in soil, SRVs, and SLVs are expressed in units of milligrams per kilogram (mg/kg). BRAUN INTERTEC