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Random sampling locations for comparing a mean with a fixed threshold (parametric) Summary This report summarizes the sampling design used, associated statistical assumptions, as well as general guidelines for conducting post-sampling data analysis. Sampling plan components presented here include how many sampling locations to choose and where within the sampling area to collect those samples. The type of medium to sample (i.e., soil, groundwater, etc.) and how to analyze the samples (in-situ, fixed laboratory, etc.) are addressed in other sections of the sampling plan. The following table summarizes the sampling design developed. A figure that shows sampling locations in the field and a table that lists sampling location coordinates are also provided below. SUMMARY OF SAMPLING DESIGN Primary Objective of Design Compare a site mean tq a fixed threshold Type of Sampling Design Parametric Sample Placement(Location) Simple random sampling in the Field Working (Null)Hypothesis The mean value at the site exceeds the threshold Formula for calculating Student's t-test number of sampling locations Calculated total number of samples 13 Number of samples on map a 13 Number of selected sample areas b 1 Specified sampling area° 189468.27 ftz Total cost of sampling d $7,900.00 a This number may differ from the calculated number because of 1) grid edge effects, 2) adding judgment samples, or 3) selecting or unselecting sample areas. b The number of selected sample areas is the number of colored areas on the map of the site. These sample areas contain the locations where samples are collected. c The sampling area is the total surface area of the selected colored sample areas on the map of the site. d Including measurement analyses and fixed overhead costs. See the Cost of Sampling section for an explanation of the costs presented here.