4
in the “potential acid forming” and have a high chance of
potential acid mine drainage.
Particle Size Analysis
Figure 4 shows the results of particle size analyses done on
samples collected at the top, middle and bottom of the
waste rock pile. The curve shows fine particle fractions are
evenly distributed along slope of the waste rock pile. Also,
the coefficient of uniformity (Cu) and the coefficient of
curvature (Cc) which is used to classify soil was computed
accordingly. The average Cu and Cc values are 6.3 and 0.7
respectively, which indicates the samples are poorly graded
sand. Figure 5 is a plot of particle size distribution of com-
posite samples from Carlisle- Center, which indicates sam-
ples collected in the area range are well graded sand.
X-Ray Diffraction (XRD)
XRD was conducted on samples to better understand the
mineralogy. In this paper we show a few interesting plots
from XRD analysis. Figure 6 and 7 shows XRD spectra
of composite samples from Hillsboro and Steeple Rock
respectively. Mineralogy is summarized in Table 1.
Figure 4. A plot of particle size distribution along rock pile
slope at Copper Flat mine
Figure 5. A plot of particle size distribution of composite
samples from Carlisle-Center
Figure 6. XRD spectra of SR 6 (composite sample)
Figure 7. XRD spectra of Hill 2020 (composite sample from
tailings)