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II • <br /> 3. Sampling allocation <br /> Approximately five (5) samples, each weighing approximately one hundred and fifty <br /> (150) pounds, are required from an individual Toad in order to calculate the Measured <br /> Contamination Level with a sufficient level of accuracy for every material stream except <br /> Commercial Organic Materials. Because of the variability typically found in Toads of <br /> Commercial Organic Materials, approximately fifteen (15) samples of two hundred (200) <br /> pounds are required for sampling to achieve the specified level of accuracy. <br /> The recommended numbers of samples are based on the following factors: <br /> 1) An analysis of the composition variability among samples that were sorted during <br /> waste characterization studies of similar waste streams and programs in other <br /> West Coast communities. <br /> 2) An agreement on the acceptable level of accuracy. <br /> Table 1 indicates the statistical confidence intervals (error ranges) at the ninety percent <br /> (90 %) confidence level that are expected to result from characterizing five (5) samples <br /> per Toad, or fifteen (15) samples per Toad in the case of Commercial Plant Materials. <br /> Table 1: Samples per Load and Results <br /> Estimated Number of Expected <br /> Material stream sample weight samples statistical <br /> error range <br /> Commercial Source - <br /> Separated and Targeted 150 lbs. 5 4% <br /> Recyclable Materials <br /> Commercial Organic 200 lbs. 15 7% <br /> Materials <br /> Commercial Plant Materials 150 lbs. 5 1% <br /> Single - Family Targeted 150 lbs. 5 2% <br /> Recyclable Materials <br /> Single - Family Organic 150 lbs. 5 1% <br /> Materials - <br /> The error ranges shown above shall be interpreted as follows. When the calculation <br /> method described below provides the Measured Contamination Level of a load, the <br /> estimate will be expressed in terms of percent by weight of the entire load. The error <br /> range around the estimate reflects a percent by weight of the entire load. Thus, if the <br /> Measured Contamination Level for a given material stream is five percent (5 %), plus or <br /> minus one percent (1 %), then ninety percent (90 %) confidence that the Contamination is <br /> between four percent (4 %) and six percent (6 %) of the entire load is achieved.The <br /> Parties agree that the actual Measured Contamination Level will be the sole determinant <br /> of the percentage of Contamination in a load, and of Contractor's compliance with the <br /> maximum contamination levels. <br /> It is expected that a two (2) person crew can obtain, sort, and weigh five (5) samples in a <br /> five (5) to seven (7) hour period. <br /> 4. Test procedures <br /> Test procedures are broken down in to the following steps, which shall be used by <br /> SBWMA, or a third party designated by the SBWMA. <br /> Franchise Agreement for Collection Services with Recology San Mateo County Attachment E -1 <br /> Redwood City Page 2 of 14 <br />