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Page 6 of 8 <br />Mr. Tyler O'Donnell <br />TR -05 Response to Questions <br />8) Has the Applicant/Operator run a TCLP or similar analysis on the raw material coming out of the mine and <br />going to the kiln? <br />Analysis of the crusher fines used for reclamation and limestone ore are enclosed. The composite samples <br />obtained consist of the following: <br />> A sample of crusher fines (rejects) were composited from multiple grab samples from <br />June 11 through 13, 2015. <br />> A second sample of crusher fines (rejects) were composited from multiple grab samples from <br />June 14 through 17, 2015. <br />> A composite sample of limestone ore from multiple grab samples was collected on June 16, 2015. <br />The analyses of the crusher fines and raw materials can be found in Attachment A. <br />9) Please explain why the total metals in both samples are orders of magnitude greater than the results of the <br />TCLPs. The Division staff believes more metals would have expressed and leach through the TCLP process. <br />Please explain this apparent discrepancy in the samples total metals and was reported in the TCLP results. <br />Metals in the material are generally in the oxide form (not elemental form) in the raw material from the main <br />kiln baghouse. They become metal hydroxides in the presence of water, which then become insoluble in water <br />and they are very stable compounds. Consequently, the metal hydroxides present in the kiln feed from the main <br />kiln baghouse tend not to leach. This is demonstrated in the TCLP and Multiple Extraction Procedure (MEP) <br />tests. Even in the presence of a mild acid, as the TCLP procedure uses acetic acid, the basic nature of the metal <br />compounds is sufficient to neutralize the solution and as a result, do not typically leach significant amounts. <br />As mentioned in the following question, a TCLP test is typically used for waste streams in a municipal or <br />hazardous waste landfills to determine whether the material is a characteristic hazardous waste. <br />10) The Division believed that only two samples collected only on one day (January 13, 2015) may not be <br />representative of kiln baghouse dust Please collect additional samples to more completely characterize the <br />kiln dust The Division would prefer to have analytical testing done on multiple mixed grab samples collected <br />over a span of at least weeks. The Division believes that TCLP is an appropriate test to run to characterize <br />waste; however, the Division believes the TCLP does not adequately characterize mine rock waste. Please <br />collect additional samples over a greater temporal period. Please subject the additional samples of the kiln <br />baghouse dust to the Multiple Extraction Procedure, EPA Method 1320. <br />At the Division's request, GCC has collected additional samples to provide an additional representation of the <br />typical characteristics of the raw material from the kiln baghouse. In order to ensure the samples represent the <br />raw material from the main kiln baghouse to be placed in the quarry, they were collected when the raw mill was <br />down. As addressed in the original TR request, the baghouse dust is to be removed from the product stream <br />when the raw mill is down, which occurs approximately 10% of the time. The following samples were collected <br />during this sampling event: <br />> Two (2) daily composites (consisting of multiple grab samples) of raw material from the kiln baghouse <br />throughout the day when raw mill was down on June 18, 2015 and July 1, 2015. <br />> Two (2) half -weekly composites of crusher fines consisting of multiple grab samples <br />> One (1) composite of the quarry consisting of multiple grab samples <br />