PINEY POINT GYPSUM STACK SYSTEM
SPRING 2003
January 2003
STACK SYSTEM CLOSURE
Contracts Already Awarded for 3 Lined Reservoirs
NGS-N
OGS-N
OGS-S
NGS-N CLOSURE CONCEPT
NORTH-SOUTH CROSS SECTION
AVAILABLE
STORAGE
125 MGal
LINED
STORAGE
270 MGal
RAISED
DIKES
OLD GYPSUM
STACK-NORTH
(OGS-N)
RELIEF
DITCH
SEEPAGE
COLLECTION
DITCH
HDPE
LINER
NEW GYPSUM
STACK-NORTH
(NGS-N)
LINED RESERVOIRS
1. Interim Use - Process Water or Fresh Water Storage
80-mil HDPE
Process Water or
Fresh Water
2. Long Term Use – Fresh Water Reservoir
Grassed Surface
(Seeded or Sodded)
80-mil HDPE
Soil Cover
Fresh Water
February 2004
February 2004
February 2004
April 15, 2004
JULY 22, 2004
AVAILABLE SURGE STORAGE CAPACITY
3000
EMERGENCY
SURGE STORAGE
CAPACITY
2800
2400
2200
2000
1800
1600
1400
1200
1000
800
MEASURED
600
400
SURGE STORAGE
CAPACITY
200
0
J
F M A M J J A S O N D
2001
J
F M A M J J
2002
A S O N D
J
F M A M J J
2003
A S O N D J
11.4-INCH
STORM
AVAILABLE SURGE STORAGE CAPACITY (ACRE-FEET)
2600
F M A M J J
2004
A S O N D
PROJECTED SURGE STORAGE CAPACITY
WITH NORMAL RAINFALL
RECOMMENDED
CONSUMPTION
(MGD)
1.0
2800
LINED OGS-N
RESERVOIR AVAILABLE
2600
LINED OGS-S
RESERVOIR AVAILABLE
2200
LINED NGS-N
RESERVOIR AVAILABLE
2000
DISCOUNT NCP CAPACITY
DISCOUNT OGS-N
STORAGE CAPACITY
1800
1600
DISCOUNT OGS-S
STORAGE CAPACITY
1400
1200
PREDICTED
MEASURED
DISCOUNT NGS-N
STORAGE CAPACITY
1000
800
600
400
100-YEAR STORM
(11.4-inch rainfall)
AVAILABLE SURGE CAPACITY (ACRE-FEET)
2400
200
0
J
F
M
A
M
J
J
2003
A
S
O
N
D
J
F
M
A
M
2004
J
J
A
S
CLOSURE PLAN & POST-CLOSURE
STORM ROUTING
NCP
NGS-N
NGS-S
CAP
OGS-N
NGS-S
OGS-S
SCP
TOP CAP AREA FINAL COVER
Grassed Surface
24” Soil Cover
GYPSUM
40-mil HDPE
ULTIMATE CLOSURE OF SEEPAGE
COLLECTION DITCH
BERMUDA
GRASS
AMENDED
GYPSUM
HDPE LINER
2.5
1
24” GRASSED
SOIL COVER
GYPSUM
RUNOFF
80-MIL HDPE LINER
GEOTEXTILE
GRAVEL DRAIN
COLLECTOR PIPE
SEEPAGE
COLLECTION DITCH
COOLING / SLUDGE POND COVER
24" SOIL COVER
GRASSED SURFACE
40-MIL HDPE
SOIL FILL, AS NEEDED
SLUDGE
REINFORCEMENT
PINEY POINT GYPSUM STACK CLOSURE
PROJECTED CLOSURE SCHEDULE
May 2006
2006-07
Completed
NORTH COOLING
POND OR DAP
POND
(NCP)
SOUTH COOLING
POND NORTH
COMPARTMENT
(SCP-N)
May 2006
SOUTH COOLING
POND SOUTH
COMPARTMENT
(SCP-S)
May 2005
May 2005
Sept. 2004
OLD GYPSUM
STACK-NORTH
(OGS-N)
OLD GYPSUM
STACK-SOUTH
(OGS-S)
Completed
May 2005
NEW GYPSUM
STACK-SOUTH
(NGS-S)
May 2006
NEW GYPSUM
STACK-NORTH
(NGS-N)
PINEY POINT GYPSUM STACK CLOSURE
CLOSED SYSTEM CIRCA CY2006
NORTH COOLING
POND OR DAP
POND
(NCP)
NEW GYPSUM
STACK-NORTH
(NGS-N)
OLD GYPSUM
STACK-NORTH
(OGS-N)
SOUTH COOLING
POND (SCP)
OLD GYPSUM
STACK-SOUTH
(OGS-S)
NEW GYPSUM
STACK-SOUTH
(NGS-S)
STORAGE CAPACITY IN
STACK COMPARTMENTS
Compartment
Current Capacity, Lined Reservoir
Capacity, MGal
MGal
Gained
Storage, MGal
NGS-N
125
270
+ 145
OGS-S
110
155
+ 45
OGS-N
145
240
+ 95
SUBTOTAL
380
665
+ 285
NGS-S
300
600
+ 300
680
1,265
+ 585
TOTAL
Process Water Management
Proactive
Pay Me Now!
Process Water Management
Reactive
Pay Me Later!
RECOMMENDED CONSUMPTION
AUGUST 2004
1.0 MGD
OCTOBER 2006
0.5 MGD
DECEMBER 2006
0.3 MGD
PROJECTED WATER INVENTORY
WITH NORMAL RAINFALL
RECOMMENDED CONSUMPTION (MGD)
1.0
0.5 0.3
3600
1000
LINED OGS-N
RESERVOIR AVAILABLE
2800
SOIL-BENTONITE
CUT-OFF WALL
2400
800
MEASURED
2000
RECLAIM NGS-S AND SLOPES
BETWEEN OGS AND NGS
600
RECLAIM OGS EXTERIOR SLOPES
AND NGS-N WEST SLOPE
400
1600
1200
RECLAIM SCP-S,
SIDE SLOPES OF NGS AND
SEEPAGE DITCH AROUND NCP
800
200
400
PREDICTED FREE
WATER INVENTORY
0
J F
M A M J
J
2003
A S O N D
J F
M A M J
J
2004
A S O N D
J F
M A M J
J
2005
A S O N D
J F
M A M J
J
2006
A S O N D
0
WATER INVENTORY (MGAL)
WATER INVENTOTY OR STORAGE CAPACITY (ACRE-FEET)
3200
MAKE-UP OF WATER TO BE CONSUMED
THROUGH SEPTEMBER 2006
Current Water Inventory
160 MGal
Pore Water Drainage
360 MGal
Net Precipitation
255 MGal
(Assuming Normal Rainfall)
TOTAL TO BE CONSUMED
775 MGal
WE NEED TO STAY THE COURSE
FOR TWO MORE YEARS …………..
……………... IN ORDER TO AVOID
ANOTHER EMERGENCY