Laserfiche WebLink
We do not yet have a chemical analysis for the finished compost after the <br />biosolids have undergone the composting process. We do not expect the <br />chemical composition of the biosolids to vary significantly from those reported in <br />the attached reports of representative sample analyses of the untreated biosolids <br />from the Gypsum WWTP. <br />According to Colorado State University, an acceptable application rate for <br />compost from biosolids is 3 tons (dry weight) per acre. This is the rate proposed <br />for the American Gypsum mine site. The compost is to be applied 2 - 3 inches <br />deep and incorporated into the top 6 inches of soil using a disk harrow or other <br />similar mechanical means. Representative soil samples will be collected from <br />the application area before and after application. Metals loading will be limited to <br />comply with Regulation 64, Table 2. Nitrogen loading will be limited to <br />correspond to an agronomic rate determined by the results of preapplication soils <br />testing. It is anticipated that the maximum net nitrogen loading will be limited to a <br />value between 10 and 185 pounds per acre. The loading rate will vary with <br />application amounts and potential vegetation. <br />If you have any questions, please contact our office at (970) 945-5700. <br />Very truly yours, <br />Zancanella & Associates, Inc. <br />-O?n A "'7_ <br />Thomas A. Zancanella, P.E. <br />Attachments: Gypsum WWTP Analyses <br />Drainage Study <br />cc: Steve Onorofskie <br />z:\93503\93503.79 composting\div of red responses.doc