ARCHIVED REPORTS_REMOVAL ACTION COMPLETION REPORT

Home Browse Search

Draft Removal Action Completion Report Neighborhood C, Mountain House,CA Page 16 Table 4-Air Monitoring Laboratory Analytical Results: Dieldrin Location Results( ) Grant Downwind3 Date U wind Line Residences (Blank) 10/18/2013 <1.0 <1.0 <1.0 <1.0 10/21/2013 <0.50 <0.50 <0.50 <0.50 10/22/2013 <0.50 <0.50 <0.50 <0.50 10/23/2013 <0.50 <0.50 <0.50 <0.50 10/24/2013 <0.61 <0.61 <0.61 <0.61 10/29/2013 <0.50 <0.50 <0.50 <0.50 10/30/2013 <0.50 <0.50 <0.50 <0.50 10/31/2013 <0.50 <0.50 <0.50 <0.50 11/1/2013 <0.50 <0.50 <0.50 <0.50 11/4/2013 <0.83 <0.83 <0.83 <0.83 11/12/2013 <0.50 <0.50 <0.50 <0.50 11/13/2013 <0.50 <0.50 <0.50 <0.50 11/14/2013 <0.50 <0.50 <0.50 <0.50 11/15/2013 <0.50 <0.50 <0.50 <0.50 11/18/2013 <0.50 <0.50 <0.50 <0.50 11/25/2013 <0.50 <0.50 <0.50 <0.50 11/26/2013 <0.50 <0.50 <0.50 <0.50 11/27/2013 <0.77 <0.77 <0.77 <0.77 Note:all samples reported in micrograms per cubic meter=µg/n' 7.0 QUALITY ASSURANCE PROJECT PLAN IMPLEMENTATION A total of 215 primary samples were collected. Analytical precision was determined by analysis of laboratory control samples such as duplicate control samples, matrix spike samples, and sample duplicates. The recoveries of analytes in the control samples were within established control limits. Therefore analytical precision and accuracy were within acceptable limits. Total precision was determined by collection and analysis of duplicate samples. Seven Duplicate samples were collected as part of the QAPP. The Relative Percent Difference (RPD) was calculated for each of the pair duplicate samples. The RPD varied from 0% to 62.5% and averaged to 28.2%, which indicates that duplicate sample concentrations were sometimes lower, but on average, the total precision was within the laboratory precision of 70-130%. The laboratory analytical results of primary and duplicate samples indicate reasonable agreement between primary and duplicate sample analyses. Field accuracy was not determined because no equipment was used for sample collection. Therefore field contamination was not possible,no decontamination was required,and field blanks were not justified. Representativeness of the data was addressed by implementing the RAW and QAPP. Completeness was addressed by the iterative excavation, analysis, additional excavation, and analysis until each sub-parcel had one or more samples with laboratory reported analytical concentrations that were at or below the PRG. Laboratory reporting units are in mg/kg. Laboratory report sheets indicating analytical methods used, detection limits,and the results of the analyses are included in Appendix C.