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Indiana University Studies 



stone per day or over 2,000,000 cubic feet per yesiv for a steadj^ run. 

 Figuring on the same basis, a 5,000-barrel plant would require 

 nearly 3,500,000 cubic feet of limestone per year. The super- 

 intendent of the plant at Mitchell names a figure of 30 carloads 

 per day, which will very closely approximate the estimates given 

 above. 



Altho the waste of the quarry district is probabl}^ considerably 

 more than this during an active year, the collecting of this amount 

 at a central plant with any degree of regularity would be im- 

 possible. It will thus be seen that a cement plant could not be 

 constructed to use the waste of the quarry district economically, 

 at least if a special quarr}^ were not run to carrj^ the plant over 

 slack times. Another thing that would make it uneconomical 

 is the fact that most of the waste is in large blocks which would 

 need blasting and sledging before they would be in a form in which 

 they could be fed to the crushing machines. This cost would be 

 almost as much as the cost of blasting the material off the ''solid" 

 with high explosives, a process which would produce a large per- 

 centage of fines. 



Transportation charges to a central plant would be at least 

 5 cents per ton (the price now paid for moving cars in the district 

 if the product is to be hauled again). 



If the cost of material and the charges for loading it on the 

 cars be added to this, the resulting figure will exceed 20 cents per 

 ton at the mill. Practically every estimate of engineers as to the 

 cost of winning the raw materials and delivering it at the mill is 

 as low or lower than the above figure, where the deposits can be 

 worked by quarrying with high explosives. It will thus be seen 

 that this method of waste utilization does not offer itself as a 

 means of solving the problem in hand. 



There are a number of old quarries or openings which have 

 been worked out or have proved poor building stone, that could 

 be optioned at a very low figure. Many of these contain almost 

 unlimited supplies of limestone that, while it will not make good 

 building stone, would make an excellent grade of cement. In 

 many cases the railroad tracks are still in position, and where 

 removed the grade remains. Feeling that these might be utilized, 

 I asked several companies interested in stone quarrying with 

 explosives to give estimates of the cost of blasting the material 

 off the ''solid" for a cement plant located near these quarries 

 and delivering it to the crusher. Among the answers received, 

 the data furnished by the E. 1. DuPont de Nemours Company 



