ENFORCE33307

• Permit No: C1981018
• IBM Index Class Name: Enforcement
• Doc Date: 1/24/1994
• Doc Name: C-81-018 NOV C-93-156 COMPACTION TESTING PLAN WASTE PILE 4
• From: DMG
• To: BARBARA PAVLIK
• Violation No.: CV1993156
• Media Type: D
• Archive: No

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STATE OF COLORADO
DIVISION OF MINERALS AND GEOLOGY
Department of Natural Resources
1313 Sherman 51., Room 215
Denver, CO 80203
Phone: [phone]
FAX: [phone]
To: Barbara Pavlik, Environmental Protection Specialist
From: Bruce Stover, Technical Support
Date: January 24, 1994
Re: C-81-018, NOV C-93-156, Compaction Testing Plan, Waste Pile 4:
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Rw Romer
Governor
ntchael B. Long
Divisron Dnecior
I have reviewed the materials you gave me on the proposed compaction testing program for the
Deserado pile No. 4. There are several parts of the plan which should be clarified or expanded
upon so that we are assured of reliable data. My comments are referenced to the items as
numbered in the proposed plan:
1. In order to have confidence in the test results taken from bulldozed cuts, comparisons
of compaction values from the dozed cuts to test pits or drilled holes need to be made.
Values for compaction should be taken from test pits excavated to the same depth as the
dozed cuts to demonstrate that the weight of the dozer in repeated passes through the
pit does not increase the observed compaction through the excavation procedure itself.
The least disturbance to the in place materials would occur if a hollow-stem auger hole
were drilled, and compaction tests made every two feet. Alternatively, test pits which are
carefully excavated with a backhoe or excavator will probably not disturb the in place
materials to a significant degree.
2. It is not clear how the 10 to 15 foot depth for the test trenches was "determined". As I
recall, this figure came up in our meeting with WFU as a suggested acceptable limit for
dozer-excavated trenches. Data or records supporting the number of lifts actually placed
at the selected test locations should be used to determine the required depths of the test
trenches/pits. If this depth is greater than 10 to 15 feet, the test locations should be
required to be drilled, or alternatively, excavated by a backhoe or excavator.
5. A descriptive log of the test excavations/holes should be made during the compaction
testing program. These logs should describe the physical characteristics of each lift-(e.g.
color, texture, moisture,)-encountered and tested for verification of depths and location
within the pile.
7. The accuracy testing results from (1) above should be reviewed by our office prior to
commencing full-scale dozer trenching operations.
xc: Larry Routten