2018-07-10_INSPECTION - M1977342

• Permit No: M1977342
• IBM Index Class Name: Inspection
• Doc Date: 7/10/2018
• Doc Name: Inspection Report
• From: DRMS
• To: Henderson
• Email Name: SJM
• Media Type: D
• Archive: No

PERMIT #: M-1977-342
INSPECTOR'S INITIALS: SJM
INSPECTION DATE: June 20, 2018
OBSERVATIONS
The Henderson Mine was inspected by Stephanie Mitchell with the Division of Reclamation, Mining and Safety
(Division/DRMS) as part of the Division's monitoring inspection program. Mr. Miguel Hamarat and Mr. Alex
Ungers with Climax Molybdenum - Henderson Operations (Henderson) was present during the inspection.
The purpose of the inspection was to observe the stormwater structures located around the mine facility.
The Division and Henderson staff inspected the sixteen outfalls at the mine. A list of the outfalls with
comments from the inspection is below:
OF -1: BMP's at this outfall location consist of a series of rock check dams leading to a rip -rap outfall. The
outfall was dry and appeared to be functioning properly.
OF -2: BMP's at this outfall location consist of a series of rock check dams leading to a sedimentation pond
above the rip -rap outfall. The sedimentation pond contained water above the outfall and has a large amount
of sediment in it. The Division recommends cleaning out the sedimentation pond. The outfall appeared to be
functioning properly.
OF -3: BMP's at this outfall location consist of an engineered wetland and a sedimentation pond. Water was
flowing though the outfall and the outfall appeared to be functioning properly.
OF -4: BMP's at this outfall location consist of a vegetated area at the bottom of a slope. The outfall appeared
to be functioning properly.
OF -5: BMP's at this outfall location consist of rip -rap and vegetation leading to a sedimentation pond above a
culvert. The sedimentation pond contained water and appeared to be functioning properly.
OF -6: BMP's at this outfall location consist of rip -rap and a sedimentation pond. The outfall appeared to be
functioning properly.
OF -7: BMP's at this outfall location consist of rip -rap and rock check dams. The outfall was dry and appeared
to be functioning properly.
OF -8a: BMP's at this outfall location consist of ditch with a series of rock check dams leading to a
sedimentation pond. The ditch and sedimentation pond contained water and appeared to be functioning
properly.
OF -8b: BMP's at this outfall location consist of a series of ditch with a series of rock check dams leading to a
rip -rap outfall. The ditch leading to the outfall contained water and appeared to be functioning properly.
Sediment was observed in the road crossing culverts above the outfall. The Division recommends are culverts
are cleaned out to maintain the function of the culverts.
OF -8c: BMP's at this outfall location consist of a ditch with a series of rock check dams leading to a rip -rap
outfall. The outfall was wet and contained sediment above the rip -rap outfall. A minor erosion feature was
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