2017-06-27_REPORT - M1973021

• Permit No: M1973021
• IBM Index Class Name: Report
• Doc Date: 6/27/2017
• Doc Name: Activity Report
• From: Aggregate Industies - WCR, Inc.
• To: DRMS
• Email Name: MAC
• Media Type: D
• Archive: No

Aggregate Industries Morrison Quarry GEI Consultants, Inc.
Geotechnical Addendum, 2016 Annual Report 6 January 2017
The point scales were tallied resulting in a range of overall RMR values and classification for
a given highwall. The classifications are as follows:
RMR Value RMR Classification
0 – 20 Very Poor
21 – 40 Poor
41 – 60 Fair
61 – 80 Good
81 – 100 Very Good
3.1 North Quarry
No mining occurred within the North Quarry in 2016 and no major rock disturbances were
noted, so no new orientation data was obtained during the 2016 review. Observations of the
existing highwalls and benches, the repaired North Slope, and the North Repository Area
were conducted. Local raveling of rocks and minor instabilities were noted within the main
trunk of the North Quarry. These instabilities and raveling events are assumed to be a result
of adverse joint conditions, rock alteration, or freeze thaw weathering cycles. Typically,
rocks loosened in this manner will be small (usually less than 18 inches) and will likely be
contained on the benches. A minor rockfall event was noted in the northeast corner of the
North Quarry at approximate El. 6454 feet in 2014. The rockfall was mainly contained on the
bench immediately below, with a few rock fragments extending beyond. GEI did not observe
any changes in the rockfall disturbance in 2016. No instability was noted on the North Slope
fill or the North Repository.
No large-scale seepage was observed within the North Quarry. The water level was
6396.4 feet above MSL on January 27, 2017.
3.2 Central Quarry
No mining activity in the Central Quarry occurred in 2016 and no new orientation data was
obtained during the 2016 review. Local raveling of rocks and minor instabilities were noted
within the Central Quarry. These instabilities and raveling events are assumed to be a result
of adverse joint conditions, rock alteration, or freeze thaw weathering cycles. Typically,
rocks loosened in this manner will be small (usually less than 18 inches) and will likely be
contained on the benches.
Minor groundwater seepage was visible in the west (east facing) highwall at approximate
El. 6600 feet. This seepage activity, noted as a changed condition in the 2013 geotechnical
addendum, was compared to the 2013 documented condition (Fig. 25). The seepage was not
observed to have expanded in 2016. This seepage, while still considered minor, should be
monitored by AI in 2017.