INSPEC43217

• Permit No: C1996084
• IBM Index Class Name: Inspection
• Doc Name: Inspection Report
• Inspection Date: 1/22/2002
• Media Type: D
• Archive: No

III. COMMENTS - COMPLIANCE
Below are comments on the inspection. The comments include discussion of observations
made during the inspection. Comments also describe any enforcement actions taken during
the inspection and the facts or evidence supporting the enforcement action.
This was a partial inspection conducted by Kent Gorham of the Colorado Division of
Minerals and Geology. The purpose of this inspection was to install seismic
monitoring equipment to record potential ground vibration from blasting activities
at the Lorencito Canyon mine, specifically the Jeff Canyon surface mine portion of
the operation. Over twenty residences and the Primero K-12 School are located
within one-half mile of the mine permit boundary. The assistance of the Office of
Surface Mining (OSM) was requested as they have the necessary expertise and
equipment to monitor blast vibrations and airblast.
Explosives
Mitch Rollings and Michael Rosenthal of the OSM met this inspector in Trinidad on
January 22, 2002. We then proceeded to the Primero School to find an acceptable
location on the school grounds to install the equipment. After discussing our
needs with the school administrators, they agreed to allow installation of the
equipment in a storage shed located irmiediately west of the oval track and
football field. This small shed was not in use at the time and it had a flat
concrete floor that would be ideal for good ground contact. It also had an
available electrical power supply and a lock on the door providing some security
for the equipment. The group agreed that the shed would be the best location for
blast monitoring.
Mr. Rosenthal set up two Instatel Seismographs in the southwest corner of the
shed. Two seismographs were used, in the event of failure of one of the
seismographs. Following set-up and equipment check, the shed door was closed and
locked. We determined that the monitors should be left fora minimum of three
weeks to have the opportunity to record numerous events should they occur.
On February 19, 2002, the group returned to retrieve the equipment. The shed door
was found locked and the equipment was found as it had been left on January 19,
2002. Mr. Rosenthal inadvertently triggered one of the seismographs as he
approached it to dis-assemble the units. Following retrieval, the group reviewed
the data in the school office. Three events were recorded: one on January 19,
2002 when system function was checked, one on February 15, 2002 that was believed
to be a recording of a blast-induced event, and one from the accidental triggering
of the unit on February 19, 2002.
Mr. Rosenthal's report is included as pages 6 and 7 of this report. It consists
of his written findings following review of the data and an actual printout of the
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