Donlin Gold Project DEIS Donlin Gold Project EIS Barge … Traffic_web.pdf · affected or displaced...
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Donlin Gold Project EIS Donlin Gold Project DEIS Barge Traffic Kongiganak Kwigillingok Aniak N Quinhagak Bethel Crooked Creek Village The Donlin Gold project would introduce additional fuel and cargo barge traffic to the Kuskokwim River. Residents of the region have expressed concerns about potential impacts to river banks, fish, and displacement of other uses, including subsistence and commercial fishing. The Draft EIS provides in-depth analysis of potential effectsfor the proposed project (Alternative 2), as well as three alternatives designed to reduce barge traffic frequency or distance. Some key questions brought forward by local residents are summarized here. Could barges successfully deliver the needed fuel and equipment during high water and low water years? Because water level in the Kuskokwim fluctuates seasonally, load management would be key to successful barge delivery over any given season. During low water periods, barges would be partially loaded to minimize risk of stranding. The proposed barging plan is based on modeling for a wide range of contingencies, including ordinary to extreme high and low water conditions, and specific barging situations such as a standing wave event. The analysis of river flow from 1952 – 2009 indicates that sufficient river flow to move fuel and cargo would occur in 97% of years during the mine life. What would be the impacts to other uses, including subsistence and commercial fisheries? Periods of interference with drift nets could occur for limited periods during barge season, in narrow locations along the river where communities conduct subsistence fishing. Subsistence users would likely avoid drift netting during the time that a barge tow takes to transit a subsistence fishing area (approximately an hour). The greatest potential effect from downstream barge traffic would be in the vicinity of Aniak and Upper Kalskag. Commercial fishing in the Kuskokwim could also be affected or displaced by project-related barge traffic, mostly by the ocean- going barges (26 per year in operations) in the Kuskokwim River below Bethel. For detailed information, please see the Draft EIS sections 3.13 Fish and Aquatic Resources and 3.21 Subsistence. What measures or operating practices could be used to reduce impacts to other users of the river? There are many design features incorporated into the project to reduce impacts, such as the natural gas pipeline, which reduces diesel fuel barging from 100 million gallons per year to 40 million gallons per year. Ocean and river fuel barges would be double hulled and have multiple isolated compartments for transporting fuel to reduce the risk of a spill. In addition, possible mitigation measures or ways to reduce impactsinclude: • Managing barge loads within the constraints of river flow and navigability adds safety, minimizes the number of barge trips each shipping season, and helps to avoid strandings during low water years. • Barge speeds would be managed to minimize impacts to riverbanks and aquatic life. 0 200 400 Feet Estimated Propeller-induced Water Velocity at Streambed, Kuskokwim River Kuskokwim River Velocities on Streambed Feet/Second 3.4 3.0 2.0 1.0 0.0 Donlin Gold Project Proposed River Tug Typical River Tug Barge Barge Barge Barge Barge Results for upstream travel in shallow water (3 ft under keel); at full throttle (600 hp/prop - proposed, 375 hp/prop - existing); 4 props/tug proposed, 2 props/typical. Source: AECOM 2015d Aniak Crooked Creek Village Bethel Stony River Dutch Harbor Angyaruak Port Site, proposed by Alternative 2 Birch Tree Crossing Port Site, proposed by Alternative 4 Three, closely situated, upriver barge landings are proposed during construction of the pipeline: an estimated X seasons of XX upriver barge trips per season. Ocean barges would carry fuel and cargo from Dutch Harbor to Bethel. Shipping vessels would carry fuel and cargo from Pacific Northwest ports to Dutch Harbor. How would the propeller force from the proposed tugs compare to current river tugs? The figure to the left illustrates the shape and intensity of propeller-induced water velocity behind a proposed river tug, compared to a typical river tug used on the Kuskokwim River. The effect of the propeller wash under various conditions is addressed in detail in the Draft EIS, Section 3.5 Surface Water Hydrology. Wave effects depend primarily on river depth and width in a given area of river, as well as speed of travel, propeller size, and proximity to the bank. The shallower and more confined the reach, the greater the effect of waves. The deeper and wider the reach, the more the wave force is dissipated within the water body. Maximum wave heights were calculated to be between 0.05 and 0.22 feet during upstream travel, and 0.34 to 0.74 feet for downstream travel. Minor to moderate impacts are estimated along narrow reaches of the Kuskokwim River due to bank erosion and riverbed scour from propeller force, with possible minor to moderate impacts on subsistence resources and habitat. Examples of narrow reaches and available channel widths at low flow include Nelson Island, just upstream of Tuluksak (129 ft), Birch Tree Crossing (415 ft), Aniak (354 ft), Holokuk (576 ft) and Upper Oskawalik (214 ft). How much would shipping for the proposed project increase barge traffic over current levels? The table to the left shows estimated project-related cargo and fuel barging during construction and operations phases, compared to estimated current levels. As summarized in the table to the left, three other alternatives analyzed in the Draft EIS would reduce the number of project- related barges or distance of barge travel. Summary of Conclusions Based on the analysis for Donlin Gold’s proposed alternative (Alternative 2), the potential impacts due to barging are summarized as moderate due to an increase in barge traffic between the Bethel and Angyaruaq (Jungjuk) ports, and an increase in barge receipts at the Port of Bethel. Impacts under Alternative 3B, and Alternative 4 would be minor, and lower in intensity due to a smaller increase in barge traffic or reduced barge distance and less disturbance compared to Alternative 2. Note: This topic poster is designed to give a general overview. More information on Barge Traffic can be found in the Draft EIS in Chapter 2, (Alternative 2, # A, 3B, and 4), as well as sections: 3.5 Surface Water Hydrology, 3.12 Wildlife, 3.13 Fish and Aquatic Resources, 3.21 Subsistence, 3.23 Transportation, and 3.24 Spill Risk. 1 Current barge traffic typically consists of one or two 40 by 160 ft barges with a pusher tug. 2 Total would be 200 trips over four years. The exact distribution would be determined during final design. 3 Average. Actual number would range from 9 to 29 annually. 4 Figures represent peak years. 1 Barge frequency is the same as for Alternative 2 , however the distance is reduced by 75 miles (or 38%). One Typical river barge equals 40 ft by 160 ft; 4-barge tow equals 88 ft by 414 ft including the tug. Village of Crooked Creek Native Village of Napaimute Native Village of Chuathbaluk Native Village of Aniak Knik Tribe Akiak Native Community River miles from Bethel to: Birch Tree Crossing site: 124 Angyaruak site: 199 Crooked Creek: 208 Aniak: 138 Between Birch Tree and Angaruak sites: 75 Photos: Dave Cannon and Donlin Gold LLC
Transcript of Donlin Gold Project DEIS Donlin Gold Project EIS Barge … Traffic_web.pdf · affected or displaced...
Donlin Gold Project EISDonlin Gold Project DEIS
Barge Traffic
KongiganakKwigillingok
Aniak
N
Quinhagak
Bethel
Crooked Creek
Village
The Donlin Gold project would introduce additional fuel and cargo barge traffic to the Kuskokwim River. Residents of the region have expressed concerns about potential impacts to river banks, fish, and displacement of other uses, including subsistence and commercial fishing. The Draft EIS provides in-depth analysis of potential effectsfor the proposed project (Alternative 2), as well as three alternatives designed to reduce barge traffic frequency or distance. Some key questions brought forward by local residents are summarized here.
Could barges successfully deliver the needed fuel and equipment during high water and low water years?
Because water level in the Kuskokwim fluctuates seasonally, load management would be key to successful barge delivery over any given season. During low water periods, barges would be partially loaded to minimize risk of stranding. The proposed barging plan is based on modeling for a wide range of contingencies, including ordinary to extreme high and low water conditions, and specific
barging situations such as a standing wave event. The analysis of river flow from 1952 – 2009 indicates that sufficient river flow to move fuel and cargo would occur in 97% of years during the mine life.
What would be the impacts to other uses, including subsistence and commercial fisheries?
Periods of interference with drift nets could occur for limited periods during barge season, in narrow locations along the river where communities conduct subsistence fishing. Subsistence users would likely avoid drift netting during the time that a barge tow takes to transit a subsistence fishing area (approximately an hour). The greatest potential effect from downstream barge traffic would be in the vicinity of Aniak and Upper Kalskag. Commercial fishing in the Kuskokwim could also be affected or displaced by project-related barge traffic, mostly by the ocean-going barges (26 per year in operations) in the Kuskokwim River below Bethel. For detailed information, please see the Draft EIS sections 3.13 Fish and Aquatic Resources and 3.21 Subsistence.
What measures or operating practices could be used to reduce impacts to other users of the river?
There are many design features incorporated into the project to reduce impacts, such as the natural gas pipeline, which reduces diesel fuel barging from 100 million gallons per year to 40 million gallons per year. Ocean and river fuel barges would be double hulled and have multiple isolated compartments for transporting fuel to reduce the risk of a spill. In addition, possible mitigation measures or ways to reduce impactsinclude:
• Managing barge loads within the constraints of river flow and navigability adds safety, minimizes the number of barge trips each shipping season, and helps to avoid strandings during low water years.
• Barge speeds would be managed to minimize impacts to riverbanks and aquatic life.
0 200 400Feet
Estimated Propeller-inducedWater Velocity at Streambed,Kuskokwim River
Ku
s k ok w
i m R
i ve
r
Velocities on Streambed
Feet/Second3.43.0
2.0
1.0
0.0
Donlin Gold Project
Proposed River Tug
TypicalRiver Tug
Barg
e
Barg
eBa
rge
Barg
eBa
rge
Results for upstream travel in shallow water (3 ft under keel); at full throttle (600 hp/prop - proposed, 375 hp/prop - existing);4 props/tug proposed, 2 props/typical.Source: AECOM 2015d
Aniak
Crooked Creek
Village
Bethel
Stony River
DutchHarbor
Angyaruak Port Site, proposed by Alternative 2
Birch Tree Crossing Port Site, proposed by Alternative 4
Three, closely situated,upriver barge landings
are proposed duringconstruction of the
pipeline: an estimated X seasons of XX upriver
barge trips per season.
Ocean barges would carry fuel and cargo from Dutch Harbor to Bethel.
Shipping vessels would carry fuel and cargo from
Paci�c Northwest ports to Dutch Harbor.
How would the propeller force from the proposed tugs compare to current river tugs?
The figure to the left illustrates the shape and intensity of propeller-induced water velocity behind a proposed river tug, compared to a typical river tug used on the Kuskokwim River. The effect of the propeller wash under various conditions is addressed in detail in the Draft EIS, Section 3.5 Surface Water Hydrology.
Wave effects depend primarily on river depth and width in a given area of river, as well as speed of travel, propeller size, and proximity to the bank. The shallower and more confined the reach, the greater the effect of waves. The deeper and wider the reach, the more the wave force is dissipated within the water body. Maximum wave heights were calculated to be between 0.05 and 0.22 feet during upstream travel, and 0.34 to 0.74 feet for downstream travel.
Minor to moderate impacts are estimated along narrow reaches of the Kuskokwim River due to bank erosion and riverbed scour from propeller force, with possible minor to moderate impacts on subsistence resources and habitat. Examples of narrow reaches and available channel widths at low flow include Nelson Island, just upstream of Tuluksak (129 ft), Birch Tree Crossing (415 ft), Aniak (354 ft), Holokuk (576 ft) and Upper Oskawalik (214 ft).
How much would shipping for the proposed project increase barge traffic over current levels?
The table to the left shows estimated project-related cargo and fuel barging during construction and operations phases, compared to estimated current levels.
As summarized in the table to the left, three other alternatives analyzed in the Draft EIS would reduce the number of project-related barges or distance of barge travel.
Summary of Conclusions
Based on the analysis for Donlin Gold’s proposed alternative (Alternative 2), the potential impacts due to barging are summarized as moderate due to an increase in barge traffic between the Bethel and Angyaruaq (Jungjuk) ports, and an increase in barge receipts at the Port of Bethel. Impacts under Alternative 3B, and Alternative 4 would be minor, and lower in intensity due to a smaller increase in barge traffic or reduced barge distance and less disturbance compared to Alternative 2.
Note: This topic poster is designed to give a general overview. More information on Barge Traffic can be found in the Draft EIS in Chapter 2, (Alternative 2, # A, 3B, and 4), as well as sections: 3.5 Surface Water Hydrology, 3.12 Wildlife, 3.13 Fish and Aquatic Resources, 3.21 Subsistence, 3.23 Transportation, and 3.24 Spill Risk.
1 Current barge traffic typically consists of one or two 40 by 160 ft barges with a pusher tug. 2 Total would be 200 trips over four years. The exact distribution would be determined during final design.3 Average. Actual number would range from 9 to 29 annually.4 Figures represent peak years.
1 Barge frequency is the same as for Alternative 2 , however the distance is reduced by 75 miles (or 38%).
One Typical river barge equals 40 ft by 160 ft; 4-barge tow equals 88 ft by 414 ft including the tug.
Village of Crooked Creek Native Village of Napaimute
Native Village of Chuathbaluk Native Village of Aniak
Knik Tribe Akiak Native Community
River miles from Bethel to:
Birch Tree Crossing site: 124Angyaruak site: 199Crooked Creek: 208
Aniak: 138Between Birch Tree and Angaruak sites: 75
Photos: Dave Cannon and Donlin Gold LLC
