Name Poison Spider
Owner Black Hills Bentonite Corp.
Operator Black Hills Bentonite Corp.
Type Surface
Product Bentonite

Year

Production
Casper, Thorsen and Mills Mills)
(tons)

Employees
(Casper, Thorsen and Mills Mill)
2009
376,166
54
2008
484,942
64
2007
475,780
65
2006
459,492
58
2005
434,019
54
2004
470,685
54
2003
402,421
51
2002
307,824
49
2001
376,989
53
2000
297,919
50
1999
Idle
0

1998

6,468

67

1997

0

97

1996

   67

1995

8,012

117

1994

   96