My WebLink
|
Help
|
About
|
Sign Out
Home
Browse
Search
2015-12-21_PERMIT FILE - C1981041
DRMS
>
Day Forward
>
Permit File
>
Coal
>
C1981041
>
2015-12-21_PERMIT FILE - C1981041
Metadata
Thumbnails
Annotations
Entry Properties
Last modified
8/24/2016 6:13:37 PM
Creation date
1/5/2016 10:06:12 AM
Metadata
Fields
Template:
DRMS Permit Index
Permit No
C1981041A
IBM Index Class Name
Permit File
Doc Date
12/21/2015
Section_Exhibit Name
Tab 14 Reclamation Plan
Media Type
D
Archive
Yes
There are no annotations on this page.
Document management portal powered by Laserfiche WebLink 9 © 1998-2015
Laserfiche.
All rights reserved.
/
82
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
The water quality in the Northwest Intake Pool has met CDPS discharge <br />requirements so no treatment has been required. The water quality is not <br />expected to change so no treatment is anticipated. <br />The North Decline gravity dewatering system is the primary dewatering system for <br />the mine. The siphon will be maintained as a backup dewatering system. The <br />South Portal dewatering pipe will be abandoned. <br />As stated above the Northwest Intake Siphon has a capacity of about 220 gpm. <br />As a backup system, it will be able to handle the majority of the flow if the North <br />Decline gravity dewatering system requires maintenance due to decreasing flow <br />capacity. <br />The South Portal dewatering pipe was plugged with concrete grout. <br />Approximately 6 cubic yards of grout was pumped into the South Portal <br />dewatering pipe in January 2008. This should have been an adequate volume of <br />grout to plug approximately 2,000 feet of the 4 -inch pipe. However, the grouting <br />did not achieve a complete plug of the pipe and water continued to leak at less <br />than 1 gpm. To control the leakage, the end of the pipe was capped off and <br />encased in approximately one (1) cubic yard of concrete. The end of the South <br />Portal dewatering pipe was buried in the portal backfill. <br />The french drain system explained above on page 14 -7 has handled minor <br />seepage from the mine portal seals since it was installed during 2008. The minor <br />seepage typically evaporates and soaks into the ground before it reaches the end <br />of the north collection ditch shown on Figure 6C. <br />There was a heavy snowpack during the winter of 2010 to 2011. In the spring of <br />2011, a landowner above the mine was able to fill an irrigation pond that had not <br />been filled since the portals had been sealed. The dip of the mine workings is <br />about 2 to 5 degrees north 30 degrees east. The pond is located roughly south <br />20 degrees west of the mine portal. During late spring 2011, water from the <br />irrigation pond percolated through the rock strata and significantly increased the <br />flow in the french drain system. Flows varied from 2 to 15 gpm during late spring <br />and summer of 2011. Late in 2011 the flow rate through the french drain system <br />returned to the normal minor flow. The increase in flow rate also occurred during <br />late spring and summer of 2012 and flow was collected in sediment Pond 9. The <br />irrigation pond located southwest of the mine portals is believed to be solely <br />responsible for the increase in flow rate in the french drain system. In years when <br />the irrigation pond was dry, there was no flow increase in the french drain system. <br />TR -63 14 -30i 11/12 <br />
The URL can be used to link to this page
Your browser does not support the video tag.