REP26016

• Permit No: C1980005
• IBM Index Class Name: Report
• Doc Date: 4/22/1993
• Doc Name: 1992 REVEGETATION MONITORING REPORT
• Permit Index Doc Type: REVEG MONITORING REPORT
• Media Type: D
• Archive: No

• percent in 1990. The lowest 1992 levels were in the 1990 Wolf Creek and Wadge Pasture
(7.8 and 13.1 percent of vegetation cover, respectively), up from the lowest 1990 levels
the 1988 Wadge, 1986 Wadge Spring, and Wadge Pasture (5.1 to 8.0 percent of vegetation
cover). The highest levels in 1992 were in the 1985 Wadge (41.2 percent of vegetation
cover), followed by 1988 Wadge (33.0 percent of vegetation cover), 1985 Wolf Creek (29
percent of vegetation cover), and 1988 Wolf Creek (28.5 percent of vegetation cover).
DISCUSSION
in
.0
Cover
As can be seen in Figure 1, 1992 cover was highest in the reference areas, older Wadge
locations (Wadge Pasture and Wadge Pasture '91 areas), and the 1988 Wolf Creek area.
Although direct comparison between years is, in general, not possible, it seems that cover
values overall in 1992 have declined to the levels of 1990 which represented a recovery after
the trend of declining cover observed during the years 1987 through 1989. The drought that
characterized the latter time period seems to have abated (see Climatic Conditions, below), but
despite favorable amounts of total precipitation, the warmth of the year (total degree-days 10.5
• percent above the long term average) may have reduced the effect of the incident moisture.
The 1988 Wolf Creek, Wadge Pasture, and Wadge Pasture '91 areas all exceeded 90 percent of
the Sagebrush Reference Area cover as well as 90 percent of the Mountain Brush Reference Area
cover. The 1985 Wadge area (with confidence interval) exceeded 90 percent of the Sagebrush
Reference Area cover. If herbaceous cover only is considered (90 percent of Mountain Brush
Reference Area =43.3 percent and 90 percent of Sagebrush Reference Area = 51.5 percent), all
reclaimed areas exceeded the reference area standards in 1992, except the 1990 Wolf Creek
would not have met the Sagebrush standard.
Average vegetation cover in the reclaimed areas was highest in 1987 (72.1 percent), slightly
lower in 1988 (70.9 percent), substantially lower in 1989 (48.1 percent), somewhat higher
in 1990 (60.2 percent), yet higher in 1991 (65.4 percent), and declined somewhat in 1992
(61.9 percent). See 1992 cover tables in Appendix hand the 1987, 1988, 1989, 7990, and
1991 Revegetation Monitoring Reports for the Seneca II Mine. These average figures admittedly
• to