Appendix G 

Comparison of Route Alternatives 
Appendix G Comparison of Route Alternatives in the Rock Springs, Wyoming Area 

Note: In this table, route alternatives are compared from RP 27 to RP 120 to facilitate direct comparison. This area differs from the segment used for comparison in Chapter 2 between the Proposed Action and the Southern Energy Corridor – Copper Ridge Bypass Alternative. 

Southern Routes

Factor Proposed Action Northern Route I-80 Route South A South B 

Length (miles) 93.3 miles 107.7 miles 101.5 miles 97.5 miles 98.9 miles Pumping Requirements (number of pump stations; number of pumps; hp; electrical power requirements; acreage required)

Base Case 147.85 HP 

2,940.08 KWH 

64.66 HP 

1,285.75 KWH 

29.54 HP 

587.25 KWH 

42.48 HP 

844.6 KWH 

Valves (number; probable locations; accessibility issues)

12 14 13 12 12 

Side-slope Construction (slope class and miles) Steep slopes = 30% or greater

<10%: 3.38 

10% :0.76 20%: 1.52 

30%: 0 

Total: 5.66 

<10%: 12.71 

10%: 1.7 

20%: 0.11 30%: 0.13 

Total: 14.65

<10%: 11.52 

10%: 1.14 20%: 0.98 30%: 0.38 

Total: 13.02

<10%: 9.69 

10%: 1.81 20%: 1.78 30%: 0.09 

Total: 13.37

<10%: 8.37 

10%: 1.43 20%: 1.67 30%: 0.09 

Total: 11.56

Additional surface disturbance associated with side slope construction 

17 acres 45 acres 40 acres 41 acres 35 acres 

Truck turnarounds: 6.5 acres Roads: 50.9 acres 

Truck turnarounds: 6.9 acres Roads: 50.9 acres 

TUAs (list of anticipated EWS areas for wash crossings, road crossings, truck turnarounds, storage sites, and approximate acres)1 

Truck turnarounds: 6.5 acres Roads: 35.1 acres Waterbody <25’: 219.0 acres Waterbody 50’ > 100’: 23.0 acres 

Truck turnarounds: 9.6 acres Roads: 48.2 acres Waterbody < 25’: 104.7 acres Waterbody 50’ > 100’: 121.7 acres 

Truck turnarounds: 7.2 acres Roads: 50.9 acres Waterbody < 25’: 152.9 acres Waterbody 50’ > 100’: 36.7 acres 

Waterbody < 25’: 175.2 acres 

Waterbody 50’ > 100’: 32.1 acres 

Duration of construction (months; if multiple years would be required, state this clearly) 

5 months 6 months 7 months 6 months 5 months 

Number of spreads (number) 1 1 1 1 1 Workforce (number of workers) 296 326 355 326 296 Waterbody crossings Interm: 160 

Peren: 10 

Total: 170 

Interm: 76 

Peren: 53 

Total: 129 

Interm: 111 

Peren: 16 

Total: 127 

Interm: 131 

Peren: 14 

Total: 145 

Road crossings Paved: 19 

Gravel/ Dirt: 32 Paved roads to be bored; smaller, unpaved roads (e.g., gravel, dirt) to be open cut. 

Paved: 26 Gravel/ Dirt: 44 Same crossing methods as proposed action.

Paved: 31 Gravel/ Dirt: 43 Same crossing methods as proposed action.

Paved: 14 Gravel/ Dirt: 60 Same crossing methods as proposed action.

Paved:16 Gravel/ Dirt: 58 Same crossing methods as proposed action.

Foreign line crossings (number) Desktop: 15 

Actual estimated: 87 

Desktop: 17 

Actual estimated: 99 

Desktop: 15 

Actual estimated: 87 

Desktop: 12 

Actual estimated: 70 

Desktop: 13 

Actual estimated: 76 

Federal land ownership (miles; acres) 

Federal (BLM, FS, and BOR): 39.6 miles, 360.0 acres 

Federal (BLM and BOR): 57.3 miles, 520.9 acres 

Federal (BLM, FS, and BOR): 42.8 miles, 389.1 acres 

Federal (BLM, FS, and BOR): 48.2 miles, 438.1 acres 

Federal (BLM, FS, and BOR): 47.2 miles, 429.1 acres 

Access Roads Required (number) 

51 70 74 74 74 

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Appendix G Comparison of Route Alternatives in the Rock Springs, Wyoming Area 

Southern Routes

Factor Proposed Action Northern Route I-80 Route South A South B 

Pipe Storage / Contractor yards (number required; acres; locations) 

4-53 acres 4-53 acres 4-53 acres 4-53 acres 4-53 acres 

Hydrostatic Test water (sources and approx gallons) 

5,682,000 6,559,000 6,182,000 5,936,000 6,026,000 

OPPs Cost (installation $) $48.9 $57.9 $59.2 $53.2 $53.3 ConstructabilityConstraints/Issues (describe) 

None More steep areas Rock Springs Cooper Ridge More steep areas 

Geological Hazards Geologic hazards such as seismic events, landslides/steep slopes, subsidence, flooding/scour, avalanches, volcanism, and expansive soils were reviewed along 

each of the alternative routes. All of the routes would encounter similar potential geological hazards and conditions as that identified along the proposed route (see EIR 7), with the exception of landslides and subsidence. The Southern “A” route would have an elevated landslide risk due to the Circle Creek Canyon crossing near South Baxter. The Northern route would cross several miles of active trona mining. The I-80 route would be located near mined out coal areas with 

known subsidence. 

Poor Reclamation Potential All routes would cross soil types with the potential for poor reclamation. Regardless of its final preferred location, Overland Pass would use industry standards to 

construct the pipeline (e.g., separating topsoil from subsoil, as necessary, to avoid soil mixing), and would implement its Soil Stabilization and Restoration Plan at all locations, the reclamation and restoration mitigation measures outlined in its Plan of Development for federal lands, and site-specific reclamation and restoration mitigation measures developed for the project. 

HCAs crossed or potentiallyaffected (miles) 

Drinking Water: 7.95 

Ecological Areas: 7.65 

Populated Areas: 3.94

Drinking Water: 8.33 

Ecological Areas: 3.11 

Populated Areas: 4.58

Drinking Water: 7.95 

Ecological Areas: 3.83 

Populated Areas: 13.33

Drinking Water: 3.26 

Ecological Areas: 7.58 

Populated Areas: 4.13

Drinking Water: 3.26 

Ecological Areas: 7.58 

Populated Areas: 4.13

Occupied structures within 500 feet of ROW2 

3 40 233 14 14 

Other relevant factors Route would cross an urban 

residential area and water holding ponds. 

Routes would cross high, difficult terrain 

1See Waterbody crossings and Road crossings for number. All temporary use area (TUA) calculations are represented in acres and assume the following: 

Intermittent streams were calculated using Open-cut <25 feet wide dimensions (200 feet x 50 feet + 200 feet x 100 feet), assuming four TUAs at each crossing. 

Perennial streams were calculated using Open-cut 50 > 100 feet wide dimensions (250 feet x 75 feet + 250 feet x 125 feet), assuming four TUAs at each crossing. 

Road crossings were calculated using Two-lane roads dimensions (200 feet x 75 feet), assuming two TUAs at each crossing. 

Truck turnarounds were calculated using Stringing truck turnaround dimensions (100 feet x 150 feet), assuming one TUA every approximately 5 miles. 

2Occupied structures based on review of Overland Pass’ Snap Map (proposed route) and aerial photos. Not all occupied structures are residences but display potential recent activity (e.g., buildings 

related to oil and gas exploration or development activities). 

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