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PERMIT #- M-1980-244
<br />INSPECTOR'S..INITIALS: BMK_
<br />INSPECTION DATE: January 25; 201 1
<br />OBSERVATIONS
<br />1) , The Division conducted a partial monitoring inspection of.the site on 1/25/11: The main purpose of the inspection was to
<br />have 'a discussion with the operator regarding the ore and, overburden; and its potential to turn acidic in the future. In
<br />addition, the Division had,also received inquiry from EPA, about the site's ore and overburdens long term potential to turn
<br />acidic: In addition;,the site inspection was-also to look at the area that experienced a ,recent spill, outside containment, or
<br />lined area, that waste ported on 12/6/2010:. The operator notified the Division over the telephone, due to an HDPEI header
<br />pipe:weld break, there was a spill outside of the containment area, along the Phase IVC leach pad. The spill outside of the
<br />double'lined area:was less than what is required to;be reported to the Division and other"agencies under"the approved
<br />permit'The reportablespifQr the site has to exceed 101bs of Sodium Cyanide, before the operator is, required to no
<br />,
<br />the Division and other agencies, as out lined in the approved Emergency Response Plan. However, the.Division had
<br />requested the operator to report any cyanide spill outside of the containment area. Afterthe report is received, 'the.
<br />Division will decide if an immediate inspection is warranted. The.Division felt an immediate inspection of the site was not
<br />warranted because of the rapid actions taken by the operator: All the area that was conteminated'outside of the
<br />containment area was detoxified, with calcium hypochlorite and the soil tested in house`. Additional soilsamples were sent
<br />to an independent Iab•and itverifiecl.the samples.to have. below detectionfor WAD"cyanide: Al11the detozified.Since all-the;
<br />remedial action s.that would have been required were already implemented at the time'. this ins ,
<br />pp , ction,;it will 'not be
<br />cited as possible problem:
<br />2.) Present during the discussions were Tony. Waldron; David Bird and Berhan Keffelew, representing the Division. Timm
<br />Comer,'KevinRiley, `Mark Vanoni, Mike Ellis, jell Winterton, and Larry" Newcomer, representing CC&V. The Division asked
<br />the operator why more Iime:.was'needed to recover the ore at present and asked if the ore was going acidic. The operator's
<br />representatives explained the need.for additional, lime was due.to the size.of the pad: By the time.itreached thelower lifts,
<br />it.was losing the PH. In order to facilitate additional recovery at depth, it"required CC&V't&add more lime through the
<br />hydro jex and lime scaling process and boost the pH.. At present, the lime application for the site is at 14 16s/ton. Under
<br />Phase. 1, pad, the lime` application was 6-8 Ibs / ton. Since the depth of the pad was less, the recovery was efficient at that
<br />time and the, remained at, the optimum level for gold recover under such a design. Optimum` leaching PH. is. between
<br />10.5..;and 10.8. CC&V`also explained 'the fact that the numerous long term,dynamic and kinetic ,testing ofthe ore and
<br />overburden; has demonstrated that even _with a PH of 31 3.and 5.51 by the'time the discharge passes, through the diatreme -•
<br />and is discharged at the Carlton Tunnel, it will be neutralized. The calcite.deposit increases with'depth according to all-the
<br />deep core drill data.`In other words the net neutralization: potential is much greater at depth,than:the. net acid;generating.
<br />potential. To date, at the tunnel outlet, the,pH.has consistently registered.at 6.66., There is a continuous'recorded data for
<br />the Tunnel; since 1956. Atthe.flume:discharge point, where it is regulated by the CDPH&E, NPDES permit :the pH is
<br />normally between 7.3 and•73. Flow rate for the tunnel,averages;1,200gpm. They said the hydro jex process,.allowed.CC&V
<br />to iecover;over 1,000 ounces.of.additional gold. They also stated; that,the mine will continue, it's long term and short;term.
<br />monitoring and testing of the ore and overburden. CC&V also agreed to have a meeting arranged with, Dr. Adrian Brown,
<br />the mines consul.ting'geochemist hydro- geologist-and the Division 'at a' later date.
<br />3') After the"meeting; the cyanide spill area outside ofthe protected zone along''Phase IVC pad andthe Phase V PSSA areas
<br />were inspected. Both Timm';C.orner:and Mark Vanoni explained, how the spill occurred and the;remedial actions"taken. They
<br />explained the moment the ADR (process plant) noticed a loss in pressure; workers were dispatched'and, the pumps shut off
<br />automatically as designed. The total spill according to the"calculations, based on wetted area, depth and pore volume did .
<br />not exceed,the 10.lbs of NACN, requiredto trigger a reportable spill reportable spill.
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