|
Telephone Flat Geothermal Development Project Final EIS/EIR
|
2.2.4.5 Power Plant Construction Activities
|
|
Grading would be preceded by clearing and
grubbing, as necessary. Trees that are felled would be
cut to commercial lengths and removed. Brush and
branches would be removed and managed in
conformance with USFS requirements and applicable
waste disposal regulations. The plant pad would be
designed to balance the cut and fill. Surface gradients
on the plant pad would normally not be less than 1
percent (0.01 foot/foot). Culvert and storm drains
would be established to produce minimum velocities
in pipes of 2 feet/second for a mean annual rain.
|
|
Temporary warehouse and laydown areas would be
located within the power plant site. Any additional
laydown areas needed as a contingency during
construction would be located within previously
disturbed areas adjacent to the power plant site. The
contingency laydown areas would not be graded.
Equipment would be laid on top of the ground
surface or cropped vegetation. Upon the completion
of construction, any contingency laydown areas
utilized would be rehabilitated in conformance with
USFS site restoration requirements.
|
|
Site excavation would be accomplished with
conventional excavation equipment. Cut and fill
slopes would be 2:1 horizontal to vertical. Fill areas
would be wetted and compacted to applicable
engineering standards (90-95% compaction). The
power plant site would be gently sloped and bermed
to prevent water ponding and to direct runoff. On-site
surface drainage would be generally directed to the
plant water storage and dump pond, or carried to
natural drainage channels, as described in Section 2.2.3.5.
|
|
The plant perimeter would be bermed and secured
with a chain link fence. The power plant area would
be paved with asphalt or covered from crushed rock,
as appropriate, around concrete foundations for the
equipment, cooling tower and buildings. All
equipment and building foundations would bear on
soil structural replacement fill, as specified by the
geotechnical report prepared for the power plant site.
The existing soil under these foundations would be
removed and then compacted in layers to 90-95
percent relative compaction.
|
|
Stream No.
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
|
Service
|
Geothermal Fluid
|
HP Steam
|
Liquid to LP Flash
|
LP turbine Steam
|
Liquid to Injection
|
HP Turbine Steam
|
Gland Steam
|
Motive Steam
|
Exhaust Steam
|
|
Phase
|
L
|
V
|
L
|
V
|
L
|
V
|
V
|
V
|
2P
|
|
Pressure, psia
|
115
|
115
|
115
|
25
|
200
|
100
|
100
|
100
|
1.12
|
|
Temperature, ºF
|
338
|
338
|
338
|
242
|
242
|
332
|
332
|
332
|
105
|
|
Total Flow, Lb/h
|
3,300,000
|
581,450
|
2,718,550
|
264,359
|
2,454,191
|
573,032
|
1,768
|
6,650
|
839,159
|
|
Water, Lb/h
|
3,298,310
|
579,770
|
2,718,541
|
264,350
|
2,454,191
|
571,376
|
1,763
|
6,630
|
837,489
|
|
NCG, Lb/h
|
1,690
|
1,680
|
9
|
9
|
0
|
1,656
|
5
|
19
|
1,670
|
|
Stream No.
|
10
|
11
|
12
|
13
|
14
|
15
|
16
|
17
|
18
|
|
Service
|
1st Jet Inlet
|
2nd Jet Inlet
|
Vacuum Pump Inlet
|
Sulfur Plant Inlet
|
CWR
|
Cooling Water Supply
|
E-101 CWR
|
E-102 CWR
|
E-103 CWR
|
|
Phase
|
V
|
V
|
V
|
V
|
L
|
L
|
L
|
L
|
L
|
|
Pressure, psia
|
1.07
|
2.4
|
5.5
|
12.4
|
25
|
40
|
30
|
25
|
25
|
|
Temperature, ºF
|
81
|
81
|
81
|
92
|
93
|
71
|
94
|
89
|
91
|
|
Total Flow, Lb/h
|
3,589
|
2,847
|
2,655
|
2,558
|
34,813,716
|
34,239,540
|
32,761,325
|
239,013
|
184,624
|
|
Water, Lb/h
|
1,078
|
326
|
127
|
54
|
34,813,680
|
34,239,540
|
32,761,325
|
239,013
|
184,624
|
|
NCG, Lb/h
|
2,512
|
2,521
|
2,527
|
2,504
|
36
|
0
|
0
|
0
|
0
|
|
Stream No.
|
19
|
20
|
21
|
22
|
23
|
24
|
25
|
|
|
Service
|
Vacuum Pump CWR
|
Auxiliary CWR
|
E-102 & E-103 Condensate
|
Condensate From E-101
|
Evaporation Loss
|
Condensate to Injection
|
Air In leakage
|
|
Phase
|
L
|
L
|
L
|
L
|
V
|
L
|
V
|
|
Pressure, psia
|
12.4
|
25
|
2.4
|
1.07
|
11.4
|
25.0
|
11.4
|
|
Temperature, ºF
|
92
|
81
|
92
|
105
|
84
|
105
|
65
|
|
Total Flow, Lb/h
|
12,987
|
1,041,687
|
7,584
|
857,009
|
576,679
|
269,941
|
867
|
|
Water, Lb/h
|
12,965
|
1,041,687
|
7,581
|
856,957
|
574,195
|
269,925
|
0
|
|
NCG, Lb/h
|
23
|
0
|
4
|
52
|
2,485
|
16.50
|
867
|
|
Legend:
59 ºF Wet Bulb
512 ppm NCG in Resource
3.6% Hydrogen Sulfide in NCG
NCG = Noncondensable Gas
HP = High Pressure
LP = Low Pressure
CWR = Cooling Water Return
Source:
Adapted from CE Holt Company
Dwg. 10171-132010, Revision C
May 9, 1997
|
|
Table 2.2.3: Projected Geothermal Resource Conditions
|
|
Parameter
|
Probablea
|
Rangeb
|
|
Reservoir Temperature
|
480 º F
|
430 - 550 º F
|
|
Reservoir Enthalpy
|
470 BTU/lb
|
410 - 550 BTU/lb
|
|
Reservoir Total Dissolved Solids
|
2,500 ppm by wt
|
1,500 - 5,000 ppm by wt
|
|
Reservoir Noncondensable Gases
|
512 ppm by wt
|
100 - 1,000 ppm by wt
|
|
Wellhead Temperature
|
338 º F
|
330 - 500 º F
|
|
Wellhead Pressure
|
115 psia
|
100 - 200 psia
|
|
Total Mass Flow per well
|
367 kph
|
200 - 800 kph
|
Noncondensable Gases (NCG) in the Produced Geothermal Fluid
(Percent by weight of total NCG)
|
|
Parameter
|
Probablea
|
Rangeb
|
|
Carbon Dioxide (CO2)
|
92.3
|
90-95
|
|
Nitrogen (N2)
|
4
|
0-5
|
|
Hydrogen Sulfide (H2S)
|
3.6
|
1-5
|
|
Methane (CH4)
|
0.1
|
0-4
|
a Probable conditions based on reservoir test data and chemistry from well 87-13
b Range of conditions for similar types of hydrothermal reservoirs in the Cascade Province
Source: Personal Communication — Dale R. Schuster, CEGC; November 22, 1997
|
Telephone Flat Geothermal Development Project Final EIS/EIR
 |
|
|
