GENERAL45618

• Permit No: C1980001
• IBM Index Class Name: General Documents
• Doc Date: 7/15/1999
• Doc Name: 1999 EROSION INVENTORY REPORT
• Media Type: D
• Archive: No

\ _ _
III IIIIIIIIIIIII III
999
EDNA MINE - 1999 EROSION INVENTORY REPORT JUL 151999
Dmsion of Minerals 8 Geology
OVERVIEW
Section 4.3 of Permit No. C-80-OOl requires an azutual erosion inventory of the Edna
Mine's permanently reclaimed lands that remain under bond. The permit requires that an
inventory report be submitted to the CDMG on or before July 15 of each yeaz. The first erosion
inventory was performed in the spring of 1992 after the initial approval of the referenced permit
section. This survey included the South-of--Shop areas and the South-of--Shop erosion feature.
The second inventory was conducted in the fall of 1992. The two inventories conducted in 1992
were included in the 1993 report. The third inventory as conducted in the fall of 1993 for the
1994 report. Further changes in the permit language resulted in the inventories being performed
in the spring of each year, starting with the 1995 annual erosion inventory. The West Ridge azea
had some preliminary inventories performed during previous years, however they did not
conform to the azea designation currently used. Therefore, the preliminary data is not included in
the inventory report
Areas permanently reclaimed that are required to be inventoried under the plan include
the Moffat Area, West Ridge, and an approximately 10 acre strip in the South-of--Shop azea. In
the Moffat area, a total of 10 blocks aze included in the monitoring plan. Initial monitoring of
portions of the Moffat area began in 1992 as reclamation activities were completed on various
blocks. Block 10 of the Moffat azea was added to the inventory in 1997 as a result of completing
reclamation activities on the area during the fall of 1996. All of the West Ridge area was
incorporated into the inventory after the completion of the terraces in late 1995. The inventoried
areas are indicated on Exhibit 1, Sheets 1 and 2, of this report. Additionally, concentrated flow
features and one potentially unstable hillslope area aze monitored. The concentrated flow
features include the South-of--Shop Concentrated Flow Feature No.l (monitoring began in 1992),
and three exit channels along the Goat Trail (monitoring began in 1993). The monitored
hillslope lies immediately upslope of the reclaimed roadway that led to the C-building of the
conveyor system. Monitoring of the hillslope began in the early fall of 1996 with the initial
placement of monitoring pins. A summary containing the current year's results and the results of
the previous four years of monitoring efforts, where available, is provided for compazative
purposes.
INVENTORY METHODS
Pedestrian and vehiculaz surveys were conducted on permanently reclaimed areas to
inventory erosion features. The azeas examined and individual features noted were evaluated as
outlined in Section 4.3.
Evaluation of the overall erosion condition of various reclaimed azeas was performed in
accordance with the Bureau of Land Management's Erosion Condition Classification System
described in Technical Note No. 346. This classification system considers both sheet erosion,
and rill and gully activity. As such, the system approach enables the overall erosion condition of
1