Laserfiche WebLink
36 <br />9 Plume District, 5 adits from the Boulder Tungsten District, <br />and 6 adits from the Gold Hill District. The concentration <br />ranges of the constituents in the effluents from each dis- <br />trict are summarized in Table V. The water chemistry of <br />all 15 of these effluents compares with that of the Central <br />City Peripheral Zone. Finding a mine effluent in the Front <br />Range that is comparable in water chemistry to the Argo <br />Tunnel which drains the Central City central zone has been <br /> quite difficult. <br /> Why is it that the water quality of mine drainage improves <br /> considerably when leaving Central City? The ground water <br /> aquifer system is not the cause since all the effluents are <br />• of the diffuse flow type. The type of mineralization is <br /> not the cause since other adits have also bored into pyritic <br /> gold, especially in the Gold Hill District. It is felt that <br /> two other parameters have to be considered to explain these <br /> differences. The first is the occurrence of the ore body; <br /> localized veins of ore occurring in rock impervious to <br /> water is one extreme example, while ore disseminated through <br /> highly fractured rock which has a high porosity represents <br /> the other extreme. Diagrams of the vein system and the dis- <br /> seminated system are presented in figure 7. <br /> The disseminated ore system allows more intimate contact <br /> of the ground water with the vein minerals and also insures <br /> a diffuse flow aquifer. The Central City District with its <br />• breccia pipe glory hole in the central zone is just such an