PERMFILE131517

• Permit No: C1981019
• IBM Index Class Name: Permit File
• Doc Date: 12/11/2001
• Section_Exhibit Name: EXHIBIT 20 PERMIT REVISION DURING THIRD FIVE-YEAR PERMIT TERM
• Media Type: D
• Archive: No

• TECHNICAL REVIBION REOIIEST - REDIICTZON OF
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1) STREETER FILL
Backcrround
The history of Streeter fill represents over fifteen years of
what has to one of the most interesting and highly successful
examples of reclamation successes in the west. During this period
of time, Colowyo has continued to monitor Streeter Fill according
to the requirements set forth in Section 2.06.2 of the permit.
The current monitoring requirements for Streeter Fill include
quarterly monitoring of the 6900 bench piezometer well and
quarterly subsidence monitoring using 12 survey monuments. In
addition, quarterly inspections and certified inspection reports
are completed which include an analysis of the results of
subsidence monitoring and piezometer well inspection and a
determination regarding evidence of surficial slope failure and the
formation of springs and seeps.
The tabulation and graphical analysis of the monitoring data
as well as all inspection reports have been included in the Annual
Reclamation Reports submitted annually to the Division. As noted
• in the inspection reports, the monitoring of.streeter Fill has
continued to show no indication of any problems. The piezometer
well continues to show no indication of ground water, the
subsidence surveys have consistently shown nothing more than normal
settling of spoil and there has been no indication of springs and
seeps or surficial slope failure.
Proposal
After more than 12 years of monitoring Streeter Fill the data
supports the conclusion that the fill is stable and will continue
to be stable. For this reason, we propose to modify the monitoring
of the Streeter Fill to a reduced level of intensity that ensures
that any changes to the fill can still be detected and appropriate
actions taken if necessary.
Please see the attached revised Section 4.09 of the permit for
details regarding the reduced Streeter Fill monitoring
requirements. This proposal represents the first step in the
direction of ultimately eliminating all monitoring of Streeter
Fill. We anticipate that at some future date we will address this
issue further to"reduce or eliminate Streeter Fill monitoring.
Colowyo believes that the proposed reduced level of monitoring
will insure that the stability requirements of Rule 4.09 continue
• to be met while providing for the protection of the environment and
public safety.
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