My WebLink
|
Help
|
About
|
Sign Out
Home
Browse
Search
PERMFILE60703
DRMS
>
Back File Migration
>
Permit File
>
700000
>
PERMFILE60703
Metadata
Thumbnails
Annotations
Entry Properties
Last modified
8/24/2016 11:07:31 PM
Creation date
11/20/2007 6:49:07 PM
Metadata
Fields
Template:
DRMS Permit Index
Permit No
C1981033
IBM Index Class Name
Permit File
Doc Date
11/14/2003
Section_Exhibit Name
Exhibit 22 Subsidence Monitoring Plan
Media Type
D
Archive
No
There are no annotations on this page.
Document management portal powered by Laserfiche WebLink 9 © 1998-2015
Laserfiche.
All rights reserved.
/
50
PDF
Print
Pages to print
Enter page numbers and/or page ranges separated by commas. For example, 1,3,5-12.
After downloading, print the document using a PDF reader (e.g. Adobe Reader).
View images
View plain text
EXHIBIT 22 <br />SUBSIDENCE MONITORING NARRATIVE <br />As of the fourth quarter 1994, 15 subsidence stations are being <br />monitored on a quarterly basis. The 15 stations are as follows: <br />UA1, UT2, U1, U2, U3, U4, U5, U8, U9, U10, U11, U21, U25, U26, and <br />U27. Monitoring stations UA1, UT2, U1, U2, U3, U4, U6, U9, U10, <br />U11 and U21 have been undermined to some extent by both the C-Seam <br />and B-Seam. Monitoring station US has only been undermined by the <br />old No. 2 Mine C-Seam workings. Monitoring stations U26 & U27 have <br />been undermined by the B-Seam. Monitoring station U25 will not be <br />undermined. <br />The following Map 22-1 Subsidence Monuments & Influence Areas, <br />shows the influence area of each subsidence monitoring station over <br />the B-Seam mine plan area. The influence area could be viewed as <br />a cone with the point of the cone being the subsidence monitoring <br />station. The radius of the cone is calculated using the difference <br />in elevation between the subsidence monitoring station and the B- <br />Seam directly below and the 25° angle of draw used in the permit. <br />• Bear and the Division have been concerned about how the slope <br />stability of ancient and modern landslides overlying the workings <br />might be affected by ground subsidence. Section 2.05.6(6) of the <br />permit concludes that the north facing slopes in the area are at <br />present unstable and the potential for mass movements are probable <br />in the area with or without the temporary effects caused by <br />subsidence. However, any probable catastrophic mass movements in <br />the area are unlikely. Four of the subsidence monitoring stations <br />(U10, U11, U21 & U22) are located in ancient landslide areas to <br />monitor possible movement of the identified landslide bodies. A <br />discussion of the horizontal movement of each of the four stations <br />is presented below. <br />The survey data for each subsidence monitoring stations has been <br />presented in a visual form on the following graphs. In general, <br />the elevation of the subsidence monitoring stations has constantly <br />decreased. On some of the graphs, the rate of change in elevation <br />increases shortly after pillar extraction. Most of the subsidence <br />monitoring points are no longer over active areas of the mine and <br />therefore monitoring of them should be suspended. This lack of <br />activity is indicated on the graphs by relatively horizontal survey <br />• point distribution. All of the subsidence monitoring points will <br />be left in place. Therefore, if the need arises to perform <br />
The URL can be used to link to this page
Your browser does not support the video tag.