1992-04-22_REVISION - M1988112

• Permit No: M1988112
• IBM Index Class Name: REVISION
• Doc Date: 4/22/1992
• Doc Name: MINUTES MLRB
• Type & Sequence: AM1
• Media Type: D
• Archive: No

•
Minutes, Rpril 22-23, 1992
~}~ DR~iFT
Subject To Board Approval 23
reported dead ducks near the ponds on 2 occasions. At that time, the
operator was using propane canons and a guard armed witn a shotgun to
haze wildlife to keep it away from the ponds. Staff said Mr. Dodson
stated that Conrad Albert, ith the Division of Wildlife, had inspected
the mine area and was satisr~ed with the steps taken by the operator to
protect wildlife.
Staff said Mr. Albert was contacted by the Division, regarding his
inspection. Mr. Albert had reported that the DOW received a dead sea
gull by an anonymous individual who alleged that it was obtained from
near the mine. Mr. Albert had the specimen tested, but did not find
any cyanide. However, DOW felt the test was incomplete and ordered a
hystopath test on the sea gull. That test has not yet been completed.
Staff said that a few days after the inspection, the Division received
a call from Andre Duchane, the operator's manager for IJorth American
operations. Mr. Duchane reported 2 dead ducks by the ~:ailings pond,
but stated that the cause of death had not been determined.
Staff said that during the inspection, Mr. Lewis stated that the
operator was not required to analyze tailings and collection pond water
for cyanide. Staff referenced information contained in Exhibit A and
stated that the San Luis project monitoring requirements submitted to
the Division states that "...chemical analysis of the collection pond
seepage on a quarterly basis for the parameters identified in Table G
1-2 of the approved permit will be performed". Staff paid the table
lists total and free cyanide as parameters for which testing would be
conducted during 2 quarters of the year. During the otF~er 2 quarters
of the year, the operator would test for free cyanide only.
Staff said the monitoring requirements also state that ...any
significant variation which could affect tailings operation or
stability will reported to the MLRD as soon as the data is obtained and
the operator would work with MLRD to obtain approval for any required
modification to the approved plan." Staff said the Division feels this
requirement also refers to elevated cyanide levels.
Staff said the Division obtained samples from the effluent, the tails
slurry after going through the treatment system, and from the lower or
west tailings pond and the collection pond; the operator took the same
samples simultaneously. The operator's samples were analyzed at their
in-house lab, and the Division's samples were analyzed ~y the Health
Department.
Staff referenced information contained in Exhibit A and discussed the
analysis which indicated that the concentration o' weak acid
dissociable cyanide was 180, the free or direct cyanide was at a level
of 240 and the total cyanide was 260 parts per million. The analysis
of the water taken from the tailings pond showed weak acic dissociable
cyanide at a level of 140, free cyanide 130 and total cyanide of 120
parts per million; analysis of water taken from the collection pond
showed weak acid dissociable cyanide at a level of 80, f,ee cyanide at
90 and total cyanide at a level of 110 parts per million.