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HomeMy WebLinkAboutEnvironmental Assessment Report Proposed Nulato Wood Energy Project 1980 PRINTED IN U.S.A. ISSUED TO 42-225 HIGHSMITH S ize — \ = ENVIRONMENTAL ASSESSMENT REPORT Proposed Nulato Wood Energy Project submitted to Alaska Village Electric Co-operative, Inc. submitted by ENVIRONMENTAL SERVICES LIMITED 835 West Ninth Avenue Anchorage, Alaska 99501 August 30, 1980 EW: oat ENVIRONMENTAL ASSESSMENT REPORT Proposed Nulato Wood Energy Project Environmental Services, Ltd. was contracted by the Alaska Village Electrical Cooperative, Inc., to assess the possible environmental impacts of the operation of a pyrolytic wood gasifier-electric genera- tor set in the village of Nulato, and to also assess the impacts of possible wood harvest schemes which would fuel it. CONCLUSIONS 1. The operation of the gasifier will have no significant negative impact on the environment of Nulato. 2. If reasonable forestry and conservation practices are observed, there will be no significant negative environmental impact caused by the harvest of local trees to supply the fuel for the Nulato gasifier. 3. A small-scale, rotating harvest of the small alder-cottonwood trees on Nulato island would be the most environmentally and econo- mically optimal wood supply program. ENVIRONMENTAL ASSESSMENT REPORT: CONTENTS DESCRIPTION A. Overview B. Setting: Nulato ci Environment of Area 1) Climate 2) Watershed 3) Soils and Associated Vegetation 4) Vegetation - General 5) Wildlife 6) Fisheries 7) Visual Resources 8) Recreation 9) Historical/Archaeological 10) Transportation 11) Land Status aye Project Operations 1) Fuel Procurement and Character 2) Gasifier Operations E. Projections ENVIRONMENTAL IMPACTS A. Fuel Procurement 1) Operations Alternatives 2) Assessment of Potential Impacts on Harvest Areas B. Gasifier Operation C. Waste Handling ALTERNATIVES TO PROJECT A. No Change B. Hydroelectric Potential Cc. Yukon Region Oil Refinery D. Coal E. Oil and Gas Potential F. Wind and Solar Energy Potential 4. | SHORT-TERM USES VERSUS LONG-TERM PRODUCTIVITY 5. IRREVERSABLE AND IRRETRIEVABLE COMMITTMENT OF RESOURCES 6. OPTIMAL OPERATIONS FORMAT APPENDIX I. L.. "MAPS A. Regional Map B. Nulato Area Map C. Constraints Map Series 2. CONTACT LIST 3. REFERENCES APPENDIX II. 1. POSSIBLE EFFECTS OF OTHER WOOD-ENERGY PROPOSALS A. Various Small Scale Operations B. Large Scale Operations a DESCRIPTION A. Overview This Environmental Assessment Report (EA) was prepared to explore the potential effects on the human and natural environment of the proposed "Wood to Gas to Power" project of the Alaska Village Electric Cooperative, Inc., (AVEC). This project is a result of an attempt to develop alternatives to the cumbersome, expensive and potentially dangerous dependence on diesel fuel for power generation in the AVEC client villages in interior Alaska. Presently , most of western and central Alaskan interior villages receive shipments of diesel and fuel oils to supply power and heating needs. These shipments must come by barge up navigable rivers and inlets, since most of these villages are not connected to highway or railroad supply routes. (Air shipment is prohibitively expensive.) There are many disadvantages to this system. Dependence on ice-free conditions for barge traffic. This limits fuel deliveries to the summer and early fall, and can result in serious spring shortages after hard winters. . Utility financial problems. As world petroleum supplies dwindle and consumption levels increase, the cost of refined petroleum products (especially high- BTU fuels like diesel) will soar. Barging costs will escalate as the price of fuel rises, which will com- pound the increasing expenditures necessary for village energy supplies. M Availability. With many of the world's petroleum sources (including Alaska) scheduled to be depleted in twenty to thirty years, the question of the con- tinued availability of regular supplies of diesel fuel - irregardless of cost -.is a potentially serious one. The April, 1980, feasibility study of Galliet, Marks and Renshaw (see reference) presents several alternatives to the diesel/heating oil energy source used in AVEC vil- lages. A system utilizing locally harvested wood to supply a gasifier-generator was found to have the greatest tech- nical and economic potential. Galliet, et al, found that suitable and convenient timber stocks were more than adequate to supply the energy needs of many Yukon, Koyukuk and Kuskokwim area villages. A pyrolytic gasi- fier was purchased from the Biomass Corporation and various engineering and performance data produced by AVEC. The village of Nulato was selected as the probable first site of an in-village pilot study for the AVEC wood- electric energy development program. This Environmental Assessment specifically addresses the potential impacts of this gasifier-generator on the village and locality, both direct impacts of the gasifier operation and the various harvest methods that might provide fuel for it. Setting: Nulato The village of Nulato is located on the Yukon River, about twenty-five miles west of Galena (see maps A and B). The population of Nulato is estimated to be about 365, and the people are primarily natives of Athapascan descent. Nulato is incorporated as a second class city, with 383 persons enrolled in the village corporation, Gana-a'Yoo, Ltd.; the native regional corporation is Doyon, Ltd. The village has selected 115,200 acres in and around the village area. Salmon fishing and other subsistence activities are the mainstay of the Nulato economy. Cc. Environment of the Nulato Area 1) 2) Climate Nulato is in the Continental Climatic Zone of Alaska, which is characterized by frequent daily and seasonal temperature variations and low cloudiness, humidity and precipitation. (Fairbanks is typical of this type of climate.) Nulato receives about fourteen inches of precipitation and seventy-five inches of snow each year. The mean temperature for January is about -16°F, and the mean temperature for July is 68°F, with a mean annual temperature of 11°F to 15°F. This temperature regime and the 65° northern latitude of Nulato produces a heating season of 15,000 degree days per year. The average wind speed is 7.3 mph, out of the north. Watershed The watershed of the Nulato area is of course dominated by the Yukon River. The village and its environs are located on ancient riverbottom, a plain formed by meanders of the main river channel. As is typical of the Yukon, the surrounding areas have marshy, poorly drained alluvial soils underlain by permafrost; feeder streams and tributaries are also meandering and often follow ox-bow ponds and swamps. Sloughs and shallow incursions of the Yukon are common (see map). With the lack of topographic relief, the Nulato drainage area stretches considerable distances back into the Nulato Hills to the north. The Nulato River and Mukluk Creek are the only large streams in this drainage. Flooding can occur both in autumn (after late summer rains) or after breakup in the spring. Flooding of the townsite associated with the meandering character of Mukluk Creek and its proximity to the Yukon, have resulted in a planned relocation of the townsite to a ridge north of town. 3) Soils and Associated Vegetation Nulato, on the northwest bank of the Yukon River, is located on the boundary between two soil types: the interior Alaskan lowlands to the east, and the Norton Sound highlands to the west. U.S. Soil Conservation Service (SCS) inventories classify the village and shore area, islands and the opposite shore to a dis- tance of about three miles inland, as Histic Pergelic Cryaquepts - Typic Cryaquepts, loamy, nearly level association. This typifies the mid- and lower-Yukon flood plain. Upland areas behind the village are identified as Typic Cryochrepts, loamy, hilly to steep, and Histic Pergelic Cryaquepts, loamy, hilly to rolling association. Interior Alaskan lowlands: flood plain soils are of two basic kinds; poorly drained soils with permafrost on the lower areas, and well-drained soils with deep or no permafrost on the higher natural levees. Most of these areas are flooded occasionally, primarily in the spring. Poorly drained soil subgroups are: a) Histic Pergelic Cryaquepts, loamy, nearly level (45% of lowlands). Both acid and nonacid, calcareous soils may be present. Yukon soils are primarily calcareous at lower levels. b) Pergelic Cyrofibrists, nearly level (15%), strong- ly acidic, organic soils. The vegetation supported by these soils consists of mosses, sedges, low shrubs, black spruce (Picea mariana) and tamarack (Larix laricina), with small lakes or areas of marsh. The well-drained soil sub- groups are: a) Typic Cryofluvents, loamy, nearly level (35%), mostly nonacid, calcareous soils. b) Typic Cryorthents, very gravelly, nearly level (5%), nonacid, calcareous soils. These well-drained soils on natural levees support white spruce (Picea glauca), paper birch (Betula papyrifera), balsam poplar (Populus _ blasamifera), black cottonwood (Populus trichocarpa), quaking aspen (Populus trichocarpa), willows and alders. The flood plain soil association provides habitat for a large variety of wildlife. The well-drained soil areas are considered suitable for commercial forestry operations, but are rated moderate to poor by the SCS for road location because of flooding, susceptibility to erosion and rough terrain. Poorly-drained soils are unsuit- able for forestry or road building. Norton Sound highlands: in upland areas northwest of the river, there are rounded hills with long foot slopes and broad intervening valleys. Most of the hills and valleys are mantled with silty loess or collu- vium. There are three basic kinds of soils: well- drained soils free of permafrost on southerly-facing slopes, ridges and hilltops; poorly-drained soils with a shallow permafrost table on north-facing slopes and in valleys or depressions; and moderately-drained soils with buried ice masses on some foot slopes. Well-drained soil subgroups are: a) Typic Cryochrepts, loamy, hilly to steep (35% of highlands), generally nonacid, calcareous soils without permafrost present on slopes other than north-facing slopes. b) Typic Cryochrepts, very gravelly, hilly to steep (15%), shallow, nonacid soils on upper parts of hills and ridges. c) Typic Cryorthents, loamy, hilly to steep (5%), deep soils on low bluffs and hills close to rivers. These soils are generally nonacid and calcareous. The vegetation on these soils consists of forests of white spruce, paper birch and aspen. Poorly-drained soil subgroups are: a) Histic Pergelic Cryaquepts, loamy, nearly level to rolling (25%), are strongly acid with thick surface mats of peaty material occurring on valleys and north-facing foot slopes. b) Histic Pergelic Cryaquepts, very gravelly, hilly to steep (5%), are strongly acid with permafrost less than ten inches below the surface mat. These soils consist of thick peaty surface mats on steep north-facing slopes. c) Pergelic Cryofibrists, nearly level (5%), are strongly acid, fibrous organic soils located in scattered depressions. The vegetation supported by these soils is either tundra dominated by sedges, mosses and low shrubs, black-spruce forest, or a combination thereof. Moderately-drained soils consist of the subgroup Aeric Cryaquepts, loamy, nearly level to rolling (10%). This soil type occurs as a thin mat of acidic forest litter covering a silt loam. Vegetation on this soil consist of forests of white spruce and paper birch. 4) 10 As in the lowlands, the well-drained soils are consi- dered suitable for forestry. Growth rates are slower on moderately-drained soils. Road location is not advised on the steep slopes and rough terrain, but is possible on moderately-drained foot slopes or ridges and hilltops, although the soils have a low load sup- porting capacity and are subject to frost action. Poorly-drained soils are unsuitable for forestry or road building. Vegetation - General The dominant forms of vegetation in this area are discussed above, under soils and associated vegeta- tion. These plant communities are classified broadly as treeless bogs and closed spruce-hardwood forests. Treeless bogs in the Yukon flood plain include bog rosemary (Andiomeda polifolia), resin birch (Betula glandulosa), dwarf arctic birch (B. nana), leatherleaf (Chamaedaphne calyculata), narrow-leaf labrador-tea (ledum decumbens), labrador-tea (L. groenlandicum), sweetgale (Myrica gale), Barclay willow (Salix bar- clayi), Alaska bog willow (S. fuscescens), low blue- berry willow (S. planifolia ssp. pulchra), bog cran- berry (Vaccinium oxycoccos), bog blueberry (VES uliginosum), mountain cranberry (V. vitis-idaea), American green alder (Alnus crispa), sitka alder (A. sinuata), thinleaf alder (A. tenuifolia), red-fruit bearberry (Arctostaphylos rubra), crowberry (Empetrum nigrum), bush cinquefoil (Potentilla fruticosa), grayleaf willow (Salix glauca), netleaf willow (S. reticulata) and Beauverd spirea (Spiraea beauverdiana). The bogs are dominated by grasses, sedges and mosses. The surface is often ridged. Shrubs do not grow in the wetter areas. There are several types of closed spruce-hardwood forests in the area. Forest fires have always been an important dt aspect of the ecology of interior forests; fires are frequent and the forests have evolved under these conditions. Forest ecosystems are a mosaic of suc- cessional stages and vegetation types as a result of fire history, slope and aspect, and the presence or absence of permafrost. In general, a willow shrub stage follows fires. This willow vegetation consists of: littletree willow (Salix arbusculoides), Barclay willow, bebb willow (S. bebbiana), Scouler willow Ss scouleriana), narrow-leaf labrador-tea, labrador-tea, prickly rose (Rosa acicularis), dwarf blueberry (Vaccinium caespitosum), mountain cranberry, Ameri- can green alder, sitka alder, thinleaf alder, red-fruit bearberry, bearberry (Arctostaphylos uva-ursi), crowberry, bush cinquefoil, American red currant (Ribes triste), buffaloberry (Shepherdia canadensis), Beauverd spirea and bog blueberry. On upland, south-facing slopes, aspen tend to follow the willow stage. They mature in sixty to eighty years and are eventually replaced by white spruce. On east- and west-facing slopes and occasionally on north slopes and flat areas, paper birch tends to succeed willow. The upland forests near Nulato are primarily white spruce mixed with birch and probably have developed in this way. On the floodplain, balsam poplar is a major successional stage, being replaced eventually by white spruce. Mixed poplar/ white spruce forests and predominantly poplar stands are found near Nulato. On north-facing slopes and low areas, black spruce is often the climax species. Mature white spruce mixture forests may develop an insolating layer of litter which raises the permafrost level which in .turn creates conditions favorable for black spruce. Mature white spruce forests consist primarily of the following species: white spruce, 12 paper birch, balsam poplar, red-fruit bearberry, crowberry, narrow-leaf labrador-tea, American red currant, prickly rose,. feltleaf willow (S. alaxensis), littletree willow, Bebb willow, buffaloberry, highbush cranberry (Vibrunum edule), bearberry, resin birch, rusty menziesia (Menziesia ferruginea), bush cinque- foil, grayleaf willow, halberd willow (Salix hastata), Richardson willow (S. lanata ssp. richardsonii), park willow (S. monticola), tall blueberry willow Cx novae-angliae), Scouler willow and dwarf blueberry. Quaking aspen stages are composed primarily of quaking aspen, white spruce and black spruce. Many of the same shrubs may be present with the addition of Alaska sagebrush (Artemisia alaskana), fringed sagebrush (Artemisia frigida), common juniper (Juniperus communis) and American red raspberry (Rubus idaeus var. strigosus). Paper birch stages are composed primarily of paper birch, white spruce and black spruce. Shrubs are similar to mature white spruce forests with the addi- tion of devilsclub (Oplopanax horridus), northern black currant (Ribes hudsonianum), American red raspberry, pacific red elder (Sambucus callicarpa) and greene mountain-ash (Sorbus scopulina). Black spruce stands develop on north-facing slopes and poorly-drained lowlands. A mat of thick sphag- num mosses, sedges, grasses and heath usually compose the subordinate vegetation. Tamarack is often associated. The major plants of this forest type are: black spruce, tamarack, paper birch, white spruce, red-fruit bearberry, crowberry, labrador- tea, prickly rose, littletree willow, Bebb willow, grayleaf willow, blueberry willow, diamondleaf willow, 5) Scouler willow, bog blueberry, mountain cranberry, resin birch, dwarf arctic birch, narrow-leaf labrador- tea, rusty menziesia,. bush cinquefoil, dwarf blue- berry and bog cranberry. These stands are inter- spersed with occasional paper birch, Scouler willow and American green alder stands. Predominant lichens are Cladonia sp., and Peltigera sp. Wildlife The various habitats around Nulato - lowland bogs, black spruce flats, spruce/birch hills, and balsam poplar or spruce levees - support a wide variety of animal and bird life. Moose (Alces alces) is the primary big game animal in the riparian habitat. Large wintering concentrations are found in areas distant from the village although few are found within ten miles of Nulato due mainly to hunting pressure. Black bears (Ursus americanus ) are common in the surrounding area. Grizzly bears (U. arctos) are present in the uplands and utilize the salmon runs on the Nulato River. Both species are numerous along the Nulato River during salmon runs. The mid-Yukon drainage has high densities of mink (Mustela vison), short-tailed weasel (M. erminea), muskrat (Ondatra zibethica), red fox (Vulpes fulva) and beaver (Castor canadensis). These species are relatively scarce in the vicinity of villages. Also present are gray wolf (Canis lupus), wolverine (Gulo luscus), lynx (lynx Canadensis), least weasel (Mustela rixosa), pine marten (Martes americana), river otter (Lutra canadensis), and in some localities, coyote (Canis latrans). Villagers use the furs of some of these animals. 14 A list of other mammals present includes: porcupine (Erothizon dorsatum), snowshoe hare (Lepus ameri- canus), northern flying squirrel (Glaucomys sabri- nus), red squirrel (Tamiasciurus hudsonicus), arctic ground squirrel (Citellus undulatus), northern red- backed vole (Clethrionomys rutilus), tundra vole (Microtus eeconomur), and possibly northern bog lemming (Synaptomys borealis), brown lemming (Lemmus trimucronatus), deer mouse (Peromyscus maniculatus), meadow vole (Microtus pensylvanicus), arctic shrew (Sorex arcticus), masked shrew Gs. cinereus), dusky shrew (S. obscura) and pygmy shrew (Microsorex hoyi). Bird life is profuse and prolific during the summer with extensive migrations in spring and fall. Resi- dent species throughout the winter are primarily gallinaceous birds and owls. Willow ptarmigan (Lagopus lagopus), rock ptarmigan (L. mutus), ruffed grouse (Bonasa umbellus) and spruce grouse (Canachites canadensis), are present year-round. Sharp-tailed grouse (Pedioecetes phasianellus) occasionally may be found in upland areas, although none have been reported. Great horned owls (Bubo virginianus) nest in the area and some may remain throughout the winter. Great gray owls (Strix nebulosa), hawk owls (Surnia ulula), and boreal owls (Aegolius funereus), are probably present all year. Short-eared owls (Asio flammeus) may come and go in response to fluctuations in microtine rodent populations. The Yukon River is an important flyway for migratory waterfowl in fall and spring. The flats across the river from Nulato serve as staging centers during migration. Canada geese (Branta canadensis), as well as many species of ducks, nest in lowland areas dur- ing summer. A wide variety of passerine birds and other orders migrate through or spend the summer in the area. Among the more noticeable of these are arctic loons (Gavia arctica), common loons <G. immer), red-necked grebes (Podiceps grisegena), horned grebes (P. auritus), sandhill cranes (Grus canadensis), trumpeter swans (Olor buccinator), whistling swans (O. columbianus) and the migratory raptors. The raptors of the Nulato area include the endan- gered peregrine falcon (Falco peregrinus anatum) which nests on river cliffs. Goshawks (Accipiter gentilis), and sharp-shinned hawks (A. striatus) nest in the spruce and birch forests. Other raptors not documented but nesting in similar areas include: rough-legged hawks (Buteo lagopus), harlan's hawks (B. harlani), merlins (Falco columbarius), golden eagles (Aquila chrysaetos), bald eagles (Haliaeetus leucocephalus), ospreys (Pandion haliaetus) and marsh hawks (Circus cyaneus). Yearly nest surveys have concentrated on peregrine falcon nests so an occasional nest of these species may have been missed. They are found in other areas of the Yukon. The resident raptors rely primarily on resident prey (grouse and rodents). The migratory raptors utilize mainly migratory prey (songbirds and waterfowl) and small mammals which hibernate in winter. The peregrine falcons, which winter in South America, have been picking up heavy loads of DDT in the wintering areas. In addition, some of their migratory prey also pick up DDT in wintering areas and the falcons continue to accumulate it during the summer. 6) 16 Because of the physiological effects of DDT, pere- grine productivity has been consistently low and they were placed on the endangered species list. The summer of 1980 was a very good year for peregrines on the Yukon. Eighty young birds were observed and sixty-eight were banded by LGL biologists as compared with forty young observed and thirty-two banded the previous summer. Yukon indians regard peregrines as good luck. They are an invaluable resource - an indicator species of the ecological health of two continents - and should be carefully protected. Fisheries Three species of anadromous fish spawn in the mid-Yukon drainages - king salmon (Oncorhynchus tshawytscha), coho salmon (O. kisutch) and chum salmon (O. keta). Both king and chum salmon spawn in the Nulato River. The peak of spawning for king salmon is usually around the 25th of July. Chums appear to peak a few days to a week earlier. Alaska Department of Fish and Game surveys, made from fixed-wing aircraft, have estimated an average of 1,250 king salmon and 35,510 chum salmon, both alive and dead, during peak-time census counts for the past three years. The Nulato River is an important salmon spawning river, and salmon is a major subsis- tence item for Nulato village. Fresh-water fish species present in the Yukon River include sheefish (Stenodus leucichthys nelma), northern pike (Esox lucius), burbot (Lota lota), grayling (Thymallus arcticus), dolly varden (Salveli- nus malma), arctic char (S. alpinus), and whitefish (Coregonus nasus, C. clupeaformis and Prosopium cylindraceum). The Nulato River is an important stream for arctic char and it also supports grayling and northern pike. 7) 17 Visual Resources Nulato is situated on the northern side of the Yukon River at the confluence of Mukluk Creek. The Nulato River meanders through fairly densely wooded terrain and enters the Yukon River about a mile south of the Nulato townsite. The Nulato Hills ascend to over one thousand feet in elevation from the flat to gently sloping river bottom land surrounding Nulato. A ridge rises steeply from the banks of the Yukon River adjacent to Mukluk Creek. Nulato Island divides the Yukon River across from the Nulato townsite. The southern side of the Yukon River that is visible from Nulato is fairly flat and, for the most part, densely wooded and laced with numerous ponds. The viewshed from Nulato is limited by the low elevation, however, the road that ascends the ridge along the Yukon to the Nulato airport, as well as the development on the uplands north of town (new town- site), provide good views of the surrounding area. The installation of the power generating facilities, which would probably be located near the diesel generators, will have minimal adverse aesthetic im- pact. The location of wood harvesting areas is of some concern, however. The proposed use of alder on Nulato Island could have negligible aesthetic impact provided that vegetation buffers are retained along the shoreline. This would also be the case if trees are harvested in the vicinity of the mouth of the Soonkakat River. Harvest should be avoided, if pos- sible, on slopes that would make the harvest area visible from the Nulato townsite or the Yukon River. 8) 9) 18 Recreation Recreational activity in the Nulato area focuses on the enjoyment of the natural resources of the area. Subsistence hunting and fishing which are a means of survival, also provide recreational opportunity. The Nulato and Mukluk Rivers provide good fishing for resident and anadromous species. Most of the hunt- ing activity in the area also occurs near these streams. A few fishing enthusiasts come from other areas in the region (e.g., Fairbanks) to enjoy sport fishing near Nulato. Winter recreational activities include snowmobiling and cross country skiing. It has been noted that these activities could be aided by the trails that would be developed for tree harvest operations. It has been suggested that ski trails be cleared and the trees which are removed be used for power generation. Historical/Archeolo gical The land in and around Nulato has probably been intermittently inhabited since prehistoric times. The salmon and game supplies afforded by the streams and forage of the area would provide a fine support for a hunter-gatherer economy for small bands of early Alaskans. Although no surveys have been made in the area, it is quite possible that habitation sites and/or artifacts would be found along the banks of the Nulato River and Mukluk Creek. Habitation sites dating from historical times are lo- cated in the present viilage area and near the mouth of the Nulato River. In 1838, a Russian named Malakhov built a small, unwalled trading post on the banks of the Nulato; by 1840, it was burned down twice by the local natives, members of the Koyukukan 10) 11) I branch of the Athapascan family. In 1841, Vasili Derzhavin was sent by the Imperial Russian-American Company to rebuild the post for the third time; Derzhavin and an English naval officer, Lt. Barnard, were killed when the natives attacked and destroyed the settlement again in the spring of 1851. In 1853 or 1854, a fort with a stockade was built by the Russians several miles upriver at the present village site on Mukluk Creek. The exact locations of the Nulato River trading post and the Russian fort have not been determined. Field surveys would be neces- sary to determine danger to any historical resources by construction or logging activities in the village proper or along the Nulato River and Mukluk Creek margins. Transportation Transportation to and from Nulato is limited to river and air traffic. Three regular barge deliveries per season (approximately late May to mid-October) are scheduled by Yutana Barge Lines. A 2,800 foot gravel runway restricts the size of planes coming into Nulato; regular flights originate from Galena. Transportation within the local area is along the two miles of roads built for the new townsite, summer boating on the Yukon and snowmobile/dogsled travel over the snow. Land Status : The area in and about Nulato has been selected for individual, village or regional corporation ownership under various native land allotments. Several private plots are clustered in and about the village proper, but most of the EA study area is designated as vil- lage land; several overlapping or competing claims exist. (See Map C6). D: 20 Project Operations 1) Fuel Procurement and Character The heart of the proposed Nulato wood power project is a pyrolytic gasifier which produces a low-BTU mix of hydrocarbon gases. This machine, a Biomass Corporation Downdraft Gasifier, consumes a dry particulate fuel such as peat pellets, pulverized coal, sawdust or chipped wood. A locally harvested fuel supply greatly increases the economic viability of a project of this sort, and Nulato is in the midst of vast Yukon-margin wood resources. As previously mentioned, the primary tree species of this area are white spruce, balsam poplar (cottonwood), alder and willow, with smaller stocks of birch, aspen and black spruce. Various harvest methods may be employed, resulting in two product forms of various species combinations (e.g., spruce and birch cordwood, or willow-alder wood chips). Eventually all of the wood product must be chipped, as this is the form the feed system is designed for. Since there is an efficiency penalty in burning moist wood (many BTU's are expended in vaporizing excess water in the reaction chamber), the fuel product needs to be be airdried to a twenty-five percent moisture content, and probably further dried prior to combustion by a recycling of waste heat and hot exhaust gases through the chips. The following chart provides data on species available for Nulato's fuel supply. 21 Table 1 Moisture %, Green Heat Content (at 12% moisture) BTU/1b BTuft? BTU/cord Birch Spruce Poplar Willow Alder Aspen 40 6,675 223,000 20,000,000 35 6,800 180,000 16,000,000 55 6,675 152,000 14,000,000 50 6,700 190,000 17,000,000 50 6,700 190,000 17,000,000 45 6,675 167,000 15,000,000 2) Gasifier Operations An average pound of dried wood chips contains about 7,000 BTU. The chips are placed in a hopper and are conveyed into the reaction chamber by an automa- tic filling system. In its descent through the reac- tion chamber, the fuel particles are progressively dried and volatile compounds and water are drawn off. Some of the organics are then oxidized; the combus- tion heat creates two reduction zones (see Figure 1). The resultant gases are drawn out below the chamber, tars and particulates scrubbed out, and water re- moved. This mixture of hydrogen and hydrocarbons has about 160 BTU/ft? or roughly seventy-five per- cent of the available energy of domestic natural gas. The product gas is cooled, condensed and run through a modified diesel electric generator (see Figure 2). Figure 1 THE REACTION ZONES IN A DOWNDRAFT GASIFIER Drying 150°F 450°F Air + water vapor > a 2900 F Primary Reducti 1500°F Seconda Reducti ang G 1000 F errety Tar Formation Steam Formation Solid R Zone on Zone ry. on Zone esidue as UY FUEL DRYING 212°F PYROLYSIS 450°F OXIDATION 1,800°F REDUCTION 1,800°—600°F CARBON & ASH 600°F | Ce crate ASH (HOT) From Galliet, et al, 1980. L | FUEL GAS >—>— AIR Oxidation ‘Zone 4# Air H H XO 30 - (moisture)=> #50 (steam) OH—> HE 20 (steam) Cor O5—*> CO, H,0—*CO fy Hy 2H{O+1G0;. #.2H cole 2c6 ‘ Cc + co3* 2c CO + H,O@CO, + Ey GAS, VOLATILES, SOME TAR, STEAM (HOT. CYCLONE DUST id 23 Figure 2 A TYPICAL DOWNDRAFT GASIFIER - GENERATOR SET ELEVATING AUGER FUEL INPUT ELEVATOR FUEL STORAGE NN ' i ASH ELEVATING AUGER ' ; 1 VENT FILTER BLOWER -VENT OUST = {os 4 COOLER / CONDENSER DOWNDRAFT GASIFIER Y ENGINE GENERATOR ASH CROSS! i AUGER, From Galliet, et al, 1980. The Biomass Corporation gasifier which will be used for the Nulato project is connected to a three phase 300 kw Caterpillar electric generator. The average electrical demand for Nulato is 60 kw. About one hundred fifty pounds per hour of dry wood chips are needed to sustain such a power output. The gasifier will produce wood ash at a rate of one percent to five percent of the original weight of dry wood chips going into the reaction. Most of this ash is dirt and dust which was entrapped in bark; calcium, sodium and potassium salts are present in very small quanti- ties. The proposed Nulato gasifier would probably produce about two to seven pounds of ash per hour. 24 About fifteen pounds of water per hour also would be produced as a reaction product and would be removed from the system. This water would contain soluble and suspended tars, particulates and hydrocarbons; some of these could be carcinogenic compounds typical of the destructive distillation of wood tissue. The generator would emit exhaust gases similar to those of diesel or gasoline-fired generators. Projections Any projections on acreage requirements to supply enough wood for Nulato's present and future energy needs must depend on such factors as: 1) Species and biomass per acre of harvested trees. 2) Harvest methods and product form. 3) "Natural" versus sustained-yield harvest planning. 4) Probable increases in electrical power demand. 5) Probable conversions to electrical from oil-fired heat- ing. The 300 kw diesel-fired electrical generator presently in Nulato produces about 540,000 kwh annually, at an average rate of 60 kw per hour. This consumes about 70,000 gallons of diesel fuel annually. In addition, 25,000 gallons of heating oil per year is consumed, resulting in a total energy demand of 11.85 billion BTU per year. Any pro- jection of the future power demands of Nulato is really little better than a guess. The rate of increase in deli- vered electrical power consumption is increasing far faster in the United States than the rate of population growth, about ten to twenty percent per year; the applicability of this utilization rate to Nulato is open to question. A three percent annual growth rate for village power consumption has been suggested; this would be the equivalent of about 125,000 gallons of diesel used per year by the turn of the century. (At ten percent, it would be 470,000 gallons per year.) Nine hundred ninety cords of air-dried cottonwood has the deliverable BTU equivalent of 70,000 gallons of diesel. One thousand eight hundred cords would satisfy the three percent per annum projected demand in the year 2000. Since the same future cost and supply problems pertain to heating oil as well as diesel fuel, it would behoove Nulato to study the process of conversion of oil heating to wood and other energy sources. If a sus- tained-yield "biomass plantation" scheme is planned, the acreage alloted to supply the cordwood equivalent of pre- sent diesel-electric power production should be at least doubled for the next twenty year increment of regrowth time. That is, twice as many acres should be set aside for harvest in 2001 AD as were necessary to harvest in 1981. 2. ENVIRONMENTAL IMPACTS A. Fuel Procurement 1) Operations Alternatives There are a broad range of possible wood harvest schemes to provide fuel for the wood burning power generating system. There is a great array of equip- ment and product handling systems available for harvesting at any scale, and often most systems can be used in different ways. Nulato enjoys the poten- tial to harvest a variety of tree species from several nearby sources. There are several considerations which delineate the likely alternatives for AVEC's wood harvest plans: a) Number of villages supplied. b) Tree species and density in available harvest areas. 26 c) Physical/climate characteristics of available harvest areas. d) Seasons suitable .for each harvest technique. e) Pattern of harvest cut necessary with each technique. f) Transportation mode for harvest products. g) Management of harvested lands during regrowth. h) Availability of capital, labor and markets to support each production characteristic considered above. The April, 1980 feasibility study of Galliet, et al, examined wood harvesting systems currently available, and evaluated their suitability for use by AVEC for village power supplies. They arrived at several reasonable alternatives suitable for each scale of harvest contemplated. To assess the environmental impacts of possible harvest operations, these alter- natives were broken down into four basic scales/ methods of harvest techniques likely to be utilized for obtaining wood supplies for Nulato: a) A labor-intensive low-capital operation utilizing a small slash chipper to process sapling and pole- sized timber (SMALL CHIPPER) to supply one village. b) A labor-intensive medium-capital harvest of saw and pole-sized timber, utilizing a winch or yarder to move trimmed logs to a light cableway system which in turn moves the cut cordwood to a barge or truck; economic for two villages (YARDER-CABLE). c) A high-capital, high production system using a feller-buncher, grapple-skidder, and a _ whole- tree chipper. Chips are moved pneumatically to a barge or truck. Supplies forty villages (FELLER-CHIPPER). 27 d) A high-capital, high-productivity system using a rubber-tired feller-buncher having hydraulic shears that will cut a 20-inch tree, and up to 300 small trees per hour; the trees are yarded by a tractor-mounted grapple-skidder, bucked into cordwood, and moved to further transporta- tion by a light cableway system. Supplies 40 villages (FELLER-CABLE). Within these four basic scales of operation, there exists a set of four procedural alternatives at each scale: a) Season of Operation. i: Summer harvest, advantages: ° Relatively comfortable conditions for outside work Long daylight hours Better temperatures for machine operation Ability to use waterways for transport ii. Summer harvest, disadvantages: ° ° ° Overland transport limited in wet areas Erosion problems in vehicle use areas Soil and vegetation damage by vehicle use Access limited along banks and out to islands Disruption of summer/migratory wildlife High wood moisture content Leaves attached to branches, adding moisture to slash iii. Winter harvest, advantages: ° Easy access across snow and ice to most locations b) 28 No damage to soil or vegetation by vehicle operation No runoff or erosion problems caused by vehicle operation Low wood moisture content Low silica/dirt content of winter bark, reducing slay problems in the gasifier Provides winter employment in area dependent on summer income iv. Winter harvest, disadvantages: Hardship of cold outdoors work 2 Short daylight hours > Cold temperatures for machine opera- tion Waterways not open for distant product shipment Each season is more or less suitable for each scale of operations. For example, the more mechanized operations could be severely affected by freezeup problems. Type of Harvest. The two basic types of har- vest patterns are clear cutting and selective cutting. Each pattern has particular advantages given the site, trees and scale of each harvest. Clearcutting utilizes the most biomass/acre, but selective cutting improves the lumber potential of the trees remaining. Management of Harvested Area. This is a choice governed by local wood supplies and capital/ expertise available. Site management improves yield/acre, timber quality, and lowers regrowth d) 2 periods and risk of wood shortages. Natural regrowth requires longer regrowth times and greater timber acreage reservations, but re- quires little fertilization and tending. Product Transport. The appropriate product transport method depends on the season, scale and location of the harvest operation. In the summer, trucking product from harvest sites adjacent to settled areas on existing roads, is a cheap and convenient process. Shipping product from island or bank harvests by barge is espe- cially appropriate for high volume/long distance transport. Sleds pulled by snowmobile, snow- track, or dog team afford convenient and envi- ronmentally benign movement of products from local, small-scale winter harvests. These four alternative operation patterns for each scale/method of harvest activity forms a wide range of potential choices for wood procurement schemes. These various possibilities are presented graphically in the following Operations Matrix: a: WINTER | OPERATIONS: Permtations: 20NS 2aNs. 3eNs Gans Pe or! ALTERNA Vea ICNS isms ious 2CNS MATRIX Ss ! N,M GES NATURAL REGROWTH Product Transport] Management | Harvest Type SCALE 1-4 Harvest Type | | | | YARDER CABLE PECLER CHIPPER MANAGED GROWTH Ow) sue @ CABLE 20 SUMMER Permutations: 1SNB 2CNB 3CNB 1SNR 2CNR 3CNR 1SMB 2CMB 3CMB 1SMR 2CNR 3CNR 4CNB 4CNR 4CMB 4CNR 4SNB Likely for 4SNR Nulato: 4SMB ~ISNR 4SMR 2CNR MANAGED GROWTH Management Product Transport C,s N,M \ B,R | NATURAL REGROWTH | ROAD 31 Out of the 48 possible permutations, 26 combinations were eliminated as being unlikely, contradictory or uneconomical procedures. Of the 22 reasonable per- mutations possible for AVEC operations, four were chosen as the most likely schemes suitable for a Nulato wood harvest system: 1CNS: A small-scale, labor-intensive winter harvest of alders, willows and small cottonwood trees. This would utilize a small slash chipper, chain saws, brush hooks and chip sleds towed by snowmobile. 1SNR: A small-scale summer harvest of small trees, thinned trees and slash from an indepen- dent saw lumber plantation connected to Nulato by road. This harvest would be a by-product of summer logging operations and would use a small chipper. 2CNR: This would be a small-scale operation cutting pole and saw sized trees for chips and some lumber. It would use a light cableway to move cordwood/chips to a truck, and so in the summer, harvest area would have to be connected to the village by road. 2CNS: Similar to above; but winter operation allows the harvest area to be across wetlands or Yukon. Whole, lumber sized trees would be hard to transport, but chips or cordwood could be pulled by sled; 2CNR area could also be operated in winter by this method. The above schemes are the most appropriate and feasible ones discernable for a Nulato wood power 32 project. The potential for the actual use of each scheme is dependent of the character and location of suitable tree stands near Nulato. The suitable stands have been defined by a series of McHargian land-use constraints maps (see Constraints Map Series). These identify areas unsuitable for harvest operation and exclude them from consideration; the remaining areas are identified as to species, density and acreage. The critera for defining suitable harvest lands in the Nulato area were: a) Potential for disruption of salmon streams, aquatic life and water quality. b) Suitability for construction of summer roads and/or vehicle traffic. c) Potential disruption of endangered species habitat. d) Potential disruption of areas with possible histori- cal/archaeological resources. e) Potential ownership by individuals versus village or regional ownership. f) Presence of harvestable trees. g) Potential for disruption of wetlands and unique habitats. The combination of these constraints is displayed on Map C8. The resultant plots are shown on Map C9. Below is given a rough description of the five most suitable harvest areas: Plot. 1): Nulato. Island. This plot contains about 150 acres of large, mature cottonwood trees, about 600 acres of pole and sapling sized cottonwood/alder thickets, and about 100 acres of willows. 33 The mature cottonwoods have a density of about 5,400 ft?/acre. About one half mile from Nulato village, this island would be ideal for a winter, labor-inten- sive harvest of the alder/cottonwood/willow thickets (1CNS). Plot 2: Yukon-Soonkakat Plot. This area contains about 500 acres of very dense (8,800 ft?/acre) white spruce stands, interfingered by bog and wetlands. The wet surrounding areas and the two to three mile trip across the Yukon would necessitate a winter operation. The large tree size would call for the use of a yarder (or tractor) and a whole tree chipper (2CNS). Plot 3: Soonkakat-Patsy Slough Plot. This plot has about 400 acres of dense (7,800 ft?/acre) white spruce/cottonwood mixture. It is very similar to Plot 2, but more distant. This area would also be har- vested in the winter (2CNS). Plot 4: New Townsite Uplands. This site has about 500 acres of moderately dense (3,100 ft?/acre) white spruce/birch hillside complex. It is accessible by road, about two miles from the present village. Its location and road system make it convenient for trucking chips/cordwood and lumber or sledding chips in winter. Fairly large trees and sloping topography would require hauling equipment (2CNR, 2CNS). Plot 5: Downstream Plot. This site is a riverbank lowland, growing predominantly cottonwood. Plot 5 is 300 acres of dense cottonwood (5,800 ft?/acre). Less dense stands are nearby. Like Plots 2 and 3, this area would be harvested in winter (2CNS). 2) 34 Assessment of Potential Impacts on Harvest Areas Broad McHargian analysis excludes most areas suscep- tible to typical environmental problems; none of the defined plots are so affected. Of course, actual field exploration of each acre to be cut, could change this status. For instance, if Russian artifacts are found on Nulato Island or behind the new townsite. The following assessment identifies foreseeable impacts expected in each plot when harvested according to the probable techniques described above. Plot.2: This portion of Nulato Island contains alder, cottonwood/poplar and willow in densities of 6,000 ft*/acre. Nulato's present annual power de- mand is equivalent to about 90,000 ft? of cottonwood; this gives a yearly harvest of fifteen acres. Removal of fifteen acres of small trees during winter would be accomplished by crews using chain saws and brush hooks, running whole trees through small slash chip- pers, and hauling chips back to Nulato in snowmobile sleds. Willow/alder complexes are pioneer species and can colonize freshly deposited river alluvium and grow fully mature trees in fifteen to twenty years. Given a twenty year regrowth time, and doubling the fifteen acre yearly harvest size to a thirty acre/year harvest in twenty years, gives a 600-acre "plantation" size for sustained-yield harvesting. This acreage is available on Nulato Island. Negative impacts of Harvest Scheme: a) Slight soil compaction under snowmobile paths. b) Displacement of habitat of winter mammals/birds in fifteen acre cut. c) Noise disruption of animal activities in adjacent areas. d) Net nitrogen loss to nutrient stock of acreage. 35 Positive/Benign impacts: a) Possible enhancement of habitat for moose, beaver and other wildlife species. b) Little disruption of soil surface and nutrient content. c) No disruption of root stocks - no reseeding necessary. d) Increase of soil temperature. e) Increase of sunlight available to adjacent vegeta- tion. f) Enhancement of clinal variety. g) Snowmobile paths may become fire breaks and ski trails. h) No permanent alteration of area necessary for structures, docks, etc. Overall assessment: no discernable significant impacts to vegetation, animals or landscape; no permanent effects. Plot 2: This roughly 500 acre area, three miles from Nulato, contains dense growths of mature white spruce, about 8,800 ft® per acre. Since spruce has a seven percent higher BTU content than cottonwood, about 84,000 ft® of air-dried spruce would fulfill Nulato's present annual power demand. This could be extracted from about ten acres of Plot 2. White spruce is the climax stage of this successional series, and fully mature white spruce are typically seventy- five to one hundred fifty years old. These trees are growing on natural levees near very wet, poorly drained areas. This terrain would be impassible by vehicles in the summer, but snowmobiles and snow- tracks would have easy access routes in the winter. These large trees would be harvested by a fairly mechanized system: a winch-yarder or snow-track 36 would drag cut trees to a cableway or directly to a large whole-tree chipper. Snow sleds would haul chips or cordwood back across the Yukon. Lumber logs could be salvaged as a by-product of the wood energy harvest. Under good conditions, white spruce grows nearly as fast as cottonwood. However, it establishes itself slowly from seeds and is outcom- peted by willows, alders and cottonwood when it is small. Natural replacement in each ten acre, yearly harvest area would take many years. Two options are available for management of these cut areas: : Replace white spruce with cottonwood/alder thickets and harvest every twenty years or, Thin out deciduous saplings until the spruce establishes itself; mature trees will appear in high density within fifty years. A ten acre per year harvest of spruce would give a fifty year regrowth/rotation period for this 500-acre plot. This would simply satisfy the status quo power demand of Nulato and have no reserve for future energy consumption increases. Management Constraints to Reduce Environmental Impacts: a) Care must be taken to route snow vehicle trails over well-drained soils or frozen ponds/bogs, as low soils in this region are susceptible to disrup- tion after winter compaction. b) Margins of uncut trees must surround wetlands and bog areas to preserve the water quality of the Soonkakat River, which these drain into. Negative Impacts of Harvest Scheme: a) Snow vehicles may compact soils and cause vegetation damage. along main trails. b) Long-term change of vegetation complex may occur. c) Noise may alter winter animal behavior nearby. d) Large net nutrient-nitrogen loss to soil of har- vest area. Positive/Benign Impacts: a) Enhancement of moose/beaver habitat. b) Drying of excessive soil moisture. c) Increase of soil temperature. d) Increase of sunlight to adjacent vegetation. e) Increase of clinal variety. f) Clearings and trails reduce the potential for fire spreading. h) Little area altered for access, structures, etc. Overall assessment: if management constraints are followed, no significant negative impacts. Any long- term or permanent alterations of vicinity should be benign (e.g., conversion from one successional stage to another for small areas). Plot 3: Very similar to Plot 2; 400 acres of dense (7,800 ft?/acre) white spruce and cottonwood mix. This area would be also harvested as Plot 2 in a winter, mechanized operation. It is quite possible that Plots 2 and 3 would be managed as one unit. Twelve acres of Plot 3 would satisfy a year's demand of Nulato's present power output. Positive and negative impacts, constraints and assessment of impact significance is the same as given for Plot 2 above. a- 38 Plot 4: The hilltop acreage above Nulato has a mixture of white spruce and birch trees in moderate densities: 500 acres of about 3,100 ft°/acre. The proximity of these trees to existing roads would allow a year-round access/harvest. These mature trees would need to be harvested with some special equip- ment, including a yarder and cableway system. However, two problems would hinder large-scale development of this plot: c The necessity for roadbuilding across ridges for summer operations. ; Due to the low tree densities on these slopes, it would be necessary to harvest thirty acres of this plot to fulfill Nulato's present yearly power demand. At such a rate, Plot 4 would support this demand for fifteen years. Rather than a primary supply, this area could be a supplemen- tal or emergency stock located conveniently at the town's "back door". Management Constraints to Minimize Environmental Impacts: a) Careful construction of road cuts and pads to minimize erosion problems. b) Cutting trees on slopes not visible from Nulato proper or the new townsite, especially avoiding skylines. c) Leaving large borders of uncut timber at the downhill edge of ridgetop tree stands to minimize erosion, landslides and water quality/runoff problems. Negative Impacts: a) Possible runoff/water quality problems from erosion of logged slopes feeding Mukluk Creek and the Nulato River. 39 b) Possible deterioration of viewsheds by harvest of trees visible from Nulato. c) Noise may disturb. animal and human behavior in the vicinity. Positive/Benign Impacts: a) Enhancement of moose and small game habitat. b) Improves access of villagers to interior areas. c) Trails and cuts act as fire breaks for townsite. d) Increase of soil temperature. e) Net nitrogen removal from local nutrient pool. Overall assessment: with careful observance of management constraints, particularly erosion preven- tion, significant negative impacts. Viewshed and vegetation pattern alterations not permanent or signi- ficant. Plot 5: Similar to Plots 2 and 3 logistically. These 300 acres of mature cottonwood would also be har- vested best in a winter, mechanized operation. At 5,800 ft'/acre, about fifteen acres per year would need to be harvested. Positive and negative impacts, constraints and assessment of impact significance are the same as given for Plot 2 above. Gasifier Operations The two direct environmental products of gasifier opera- tions are noise and exhaust emissions. Exhaust emissions from combustion of the low-BTU product gas of the Bio- mass gasifier are deemed not a significant deterioration of air quality. Emissions do not produce a twenty percent reduction of visual transmissibility, nor do they produce significant increases in sulfur oxides, nitrogen oxides or 40 particulates. In fact, a properly operating gasifier, burning wood chips, will produce markedly less sulfoxides, nitroxides and particulates than a similar diesel-fired generator; installation of the gasifier in Nulato should improve air quality. Noise produced by the gasifier- generator set is deemed not a significant impact on the Nulato environment; noise levels should be similar to the output of the present diesel generator. If the gasifier is placed in an insulated structure designed to dry fuel ships with waste heat and exhaust gases, noise output should be considerably damped out. Total Negative Impacts on the Nulato Environment: None Waste Handling Two material waste products are formed as a result of gasifier reactions: ash and water. The water is both a combustion product and condensate, and it is removed by cleansing elements in the gasifier system. Since this water contains particulate and dissolved products of destructive distillation, the handling of this water may pose a health hazard due to the carcinagenic nature of these distillation products. However, a system element will be designed and installed to evaporate this water and the solid residue returned to the reaction vessel and combusted. This effectively destroys any carcinogenic compounds and pre- cludes any human contact with them. With the installation of the evaporator system, the product water is deemed to be no hazard to health or to the Nulato environment. Negative Impacts: None The wood ash is produced at the rate of about 100 pounds per day at the power output of the present Nulato genera- tor; this amounts to about twenty tons per year. This ash is a more neutral substance than ordinary wood ash, 41 since high reaction temperatures oxidize the carbon, nitrate, and phosphates in the wood, and volitize most minerals and salts. The resultant ash is almost entirely silicate products from silt and dirt trapped in bark layers. There are three potential disposal methods: 1) Dump into Yukon. Given the size of the river, this material would have negligible environmental/ecological impacts. However, the permit process necessary for this discharge would be quite cumbersome. 2) Landfill. A convenient method, and probably without any significant impact. However, the composition of the ash and the soil/drainage characteristics of the disposal area would have to be evaluated for any problems resulting from leachates draining -into streams and/or soil water. 3) Fertilizer. Distribute ash over the original fifteen acre harvest tract. This reduces the nutrient sink produced by clearcutting. If this ash is distributed evenly, especially over snowcover, there would be a definite beneficial enrichment of the soil; no negative environmental impacts. Management Constraints to Limit Impacts: Any of the three disposal methods would have no significant negative environmental impacts if care is taken to observe the provisions outlined above, especially the landfill option. The optimum disposal method would be dispersal over the harvest area, as this conserves soil nutrients. 3. 42 ALTERNATIVES TO PROJECT A. No Change Simply continuing the use of barged diesel fuel as the source of the Nulato power supply is seen as an expensive and shortsighted alternative. While this method does not subtract from the present environmental quality of Nulato, its economic feasibility is open to question. With the price of crude oil increasing at 100% to 150% per year, it is only a matter of time before Nulato simply will not be able to afford a petroleum energy base. Replacing this uncertain supply with a carefully managed, renewable energy source contributes to the economic and environmental benefits of conserving the limited fossil fuel resources of our country. Hydroelectric Power Potential Hydroelectric power generation is a clean renewable energy source; however, its applicability is severely limited by the characteristics of the locality it is to supply. The Nulato region is deemed a poor area for usable power dam sites, as it is simply. too flat. Steep gradients in canyons or deeply incised stream beds are the most suitable areas for hydroelectric dams; when flatter sites are utilized, large areas are flooded and stream life severely disrupted. In addition, the poorly drained, fine alluvial soils of the Nulato area are generally unsuitable for anchoring dam structures. Hydroelectric power is seen as not feasible for Nulato, given the geological/topographical character of the region. Hydroelectric technology may soon offer an attractive alternative in a submerged catenary-rotor water- mill of the Coriolus ocean-turbine type. This unit could be anchored in the Yukon off Nulato and utilize some of the vast energy potential of that river. Unfortunately, this concept is in the development stage and provides no answer for Nulato's present energy problems. 43 Yukon Region Oil Refinery This is an alternative based on a proposed seasonal oil refinery to be located at the Alyeska pipeline crossing of the Yukon River. Refined products would be barged downriver to user communities. If such a refinery exis- ted, then perhaps Nulato would be able to substitute the local product for diesel fuel purchased elsewhere and barged upstream. As regards to this proposal satisfying the immediate and future energy demands of Nulato, it is deemed unfeasible for these reasons: Environmental impacts. Petroleum refineries often produce large volumes of toxic wastes and/or pollu- tants creating solid, liquid and gaseous waste disposal problems. Refining of the north slope high-sulfur crude would produce these wastes and their associa- ted disposal difficulties. Inappropriate use of resources. North slope crude oil is an ephemeral resource and may be depleted in thirty years. Higher and better uses for this petro- leum should be found rather than displacing an abun- dant and renewable local energy supply. Coal Coal deposits are located in the strata in and about the Nulato area. However, these are thin, scattered seams of mostly sub-bituminous grade. The investigation by Renshaw of the area's coal potential concluded that coal was simply not economically or physically suitable as a local energy supply for Nulato. In addition, coal gasifica- tion implies environmental problems with the creation of toxic solid and gaseous wastes. These products are par- ticularly evident with use of the lower grades of coal. 44 Oil and Gas Potential Nulato is situated amidst a 2,400 square mile geological basin called the Yukon-Koyukuk Syncline. This Mesozoic formation is estimated to contain about 75,000 barrels of oil per cubic mile from 4,545 cubic miles of sediment. Accord- ing to the State of Alaska's Division of Geological and Geophysical Surveys, this would break down into 390 million barrels of recoverable oil and 900 billion barrels of recoverable natural gas. Much of this may underlie native land claims. In 1902, Oliphant reported indications of petroleum near Nulato. A test well (Nulato No. 1) was drilled in the 1940's; no petroleum was found. It is unlikely that oil and gas development will take place in the area within the next few years. If it is eventually developed, a large source of energy will be available to the residents of Nulato. Oil will need to be refined else- where and will be no more available for local use than it is at present. Natural gas, however, has potential as a direct source of fuel for electricity and heating. The composition, quality and ease of extraction of this potential resource is unknown. If gas is extractable in significant quantities, and if little or no refining is necessary for direct local use, then gas may be a reasonable alternative to diesel fuel. The economics of this option are completely unknown, and gas is at best an ephemeral resource; however, a serious exploration of the gas potential of the Nulato area should be undertaken. This alternative is seen as unproven and therefore not as feasible as the wood gasifier program for meeting Nulato's present and future energy problems. 1 45 Wind and Solar Energy Potential 1) Wind Energy Records of Nulato wind characteristics do not exist. However, it can be assumed that the wind regime of Nulato is not substantially different than that of Galena (25 miles to the east), which is the closest location with long-term climatic data. Galena has an average prevailing wind speed of about 7.3 miles per hour, from the north. In any area, the energy available from wind is constantly in flux. Therefore, use of wind as a primary energy source for a com- munity necessitates an energy storage system - usually batteries - to provide a reservoir to accomo- date a certain level of constant power demand. The size of the storage system is a function of this power demand, allowance for peak power demands, and the probable recharge rate afforded by the wind supply. Storage systems become prohibitively expensive if there are large fluctuations from baseline to peak power demands and intermittant, low-speed winds charging the system. Such is the case with Nulato. The peak power demands will take place in mid- winter; -50° temperatures and dead air are typical of the stationary high pressure systems of interior Alaska winters. The low average wind speed of Nulato would produce very low equipment efficiencies; even the best propeller-type, high-RPM Wind Energy Conversion Systems (WECS) have a stall speed of six miles per hour (a minimum average wind speed of ten miles per hour is regarded as a rule-of-thumb lower limit for practical wind power systems). Barring more favorable climatic data and WECS innovation, wind energy does not seem suitable as an alternative to supply or even supplement Nulato's power needs. 2) 46 Solar Energy Potential As with wind activity, on-site solar data is not available for Nulato. Fortunately, solar information is easier to infer than wind data; Nulato has a very similar climate to Fairbanks and is at almost exactly the same latitude. From this, we may estimate the total horizontal-surface insolation of Nulato to be about 88,000 langleys per year, or an average of 880 BTU/ft?/day. As a primary supply of energy for a community, solar power has many of the same limita- tions as wind energy, i.e., its ephemeral nature requires suitable storage; and like the wind situation, peak power demands are in the middle of winter, when only about eight percent of the average daily insolation is available. As a direct supply of electri- city, solar power is unfeasible: given the present best photovoltaic technology of low-efficiency (ten percent maximum), exorbitantly expensive photovoltaic cells, installation costs for a Nulato community power supply and storage system would be prohibitive. In fact, the wood-gasifier proposal is a much more reasonable use of the area's solar energy resources. With an eighty-five day growing season, about 2x109 kilocalories/hectare of solar energy is available for plant assimilation per year in interior forests. A twenty year old alder stand in this region can typi- cally convert 0.98% of this insolation (or about 20 million kilocalories/hectare) to biomass in the three month season. In physical terms, this represents the fixture of 2,000 kg/hectare/year of bole and stem biomass or 69 million BTU/acre/year of potential wood energy. Given a twelve percent gasifier-generator output efficiency, an acre of mature alder has the yearly useful energy capture-equivalent of over 2,100 square feet of ten percent efficient silicon photovol- taic cells. Since present prices for these cells start 47 at one hundred fifty dollars a square foot, the com- parative economy of trees as solar power converters is immediately obvious. Solar energy is clearly un- feasible as a primary power supply for Nulato, but it may be quite appropriate as a supplementary energy source. While the greatest heating demand occurs when the level of insolation is at its ebb, the twenty hours of bright sunshine (common during part of the summer) presents an untapped resource. Given a fifty-five percent capture efficiency, a twenty foot by twenty foot array of flat-plate solar collectors installed in Nulato would provide the heat equivalent of over 500 gallons of fuel oil per year. A life-cycle cost analysis makes solar water heating an attractive alternative even in the Fairbanks area, and so would probably seem even more attractive in the economic climate of Nulato. A high-efficiency trickle-down oil collector or low-efficiency passive air collector system might be likely methods of providing hot water for community clothes washing or bathing facilities; both of these systems require little maintenance and utilize collection fluids not susceptible to freezing problems. Passive solar energy utilization may be appropriate in the drying of wood chips for the Nulato gasifier. SHORT TERM USES VERSUS LONG-TERM PRODUCTIVITY ASSESSMENT: The utilization of local wood supplies to fuel a gasifier-generator set in Nulato is deemed no danger to the long-term productivity of the environment or resources of the area. Institution of this project will affect comparatively small areas. Short term changes in resource qualities may take place, (e.g., loss of soil nutrient stocks by tree harvest, or the replacement of mature spruce trees with different species) but these are either naturally renewable elements or environ- mentally negligible shifts in resource character. 48 5. IRREVERSIBLE AND IRRETRIEVABLE COMMITMENT OF RESOURCES ASSESSMENT: The Nulato gasifier and the harvest activities to fuel it will impose no permanent, irretrievable commitment of the resources of the affected area. 6. OPTIMAL OPERATIONS FORMAT ASSESSMENT: The economically and environmentally optimal wood harvest operation for Nulato would be a low-capital, labor-intensive winter harvest of the small cottonwood, alder and willow trees of Nulato Island. Here follows a conceptualization of this harvest scheme: Nulato Island has an area of about 850 acres. Of this area, about 150 acres are large, mature cottonwood trees; this acre- age possesses a significant lumber/houselog resource. About 100 acres of the island margin has willow trees of various sizes; the remaining 600 acres is covered with cottonwood (balsam poplar) and alder trees of one to four inches in diameter. This alder/cottonwood complex is conservatively estimated to contain 6,000 ft® per acre of solid wood. A clearcut harvest of about fifteen acres per year will provide wood chips enough to supply Nulato with fuel adequate to satisfy present levels of village electrical power demands; at this harvest rate Nulato Island offers a forty year supply of these small trees. If the harvest area if doubled to meet future power demands, the island af- fords a twenty year supply. Harvest on the island avoids runoff/water quality problems found in other sites, alters no significant animal/endangered species habitat and is only half a mile away from the village. Harvest activities should take place in the winter. A small party of villagers would pull equipment and chip sleds by snowmobile across the Yukon and directly to the harvest site; the frozen ground and snow cover precludes 49 the soil nutrient loss and erosion problems encountered in vehicle travel and operations in a summer harvest. The party would clearcut a selected area of trees with chain saws, brush hooks and machetes. The cut trees would be fed directly into small, portable slash chippers. While the summer moisture content of these trees is quite high (fifty percent), it may only be thirty percent in the winter. In addition, the small size may be beneficial in that a substantial quantity of the wood mass may be in twigs and shoots (which are very low in winter moisture) and which results in high bark/solid wood ratios; there is a higher BTU content in bark. The chips would be blown pneumatically into transport/storage containers, which could be large perforated plastic pipe fastened to sleds (three, twelve-foot lengths of two-foot diameter PVC pipe should hold about a ton of green wood chips; a twenty man crew, each feeding four chippers, fifty ten-pound trees an hour, would produce enough one ton loads to give five snowmobiles one load each per hour; ninety five-hour days per year at this pro- duction level would provide Nulato with a year's supply of wood chips). The filled pipes would be placed vertically in a pas- sively solar-heated chip drying building. The dark plastic would absorb heat directly and the convection characteristics of the slotted pipe and the building would drive off moisture during the one year drying period of each chip harvest. Just prior to burning, the chips would be dumped into a chip drying bin above the gasifier-generator; this bin would be heated by a combination of generator exhaust and waste heat and an ex- terior Trombe' wall inlet. The ash from generator combustion would be bagged and hauled by snowmobile back to Nulato Island. There, the pneumatic chip loader would spray the ash over the most recently harvested area. The spring melt would distribute the ash evenly back into the soil. The natural regenerative properties of alder and cottonwood roots would have new shoots soon sprouting from cut stumps. Since the soil would be still intact and a large, mature root system oper- ating, regrowth on cut areas should be rapid and automatic. 50 Management of these areas during regrowth might be in the establishment of permanent firebreaks around each plot, aphid and disease prevention, and possible applications of selected soil nutrients. Twenty years of regrowth should produce fully mature trees of three to five inches in diameter, in high densi- ties. Conceivably, this system would provide a permanent energy supply for Nulato, with very little investment in equip- ment. WALL DETAIL CONVECTION CURRENTS ie FERROCEMENT SHELL OVER FOAM wae <— SPUT LOlS on STEEL TRUSS = WARM AIR. > CREATES UPDRAFT CURRENTS ( 7 CURRENT ALZOSS [FE KX BLACK PAINT MOUTH OF TUBE ‘ NTERSTICIES FILLED WITH URETHANE FOAM AIR IS DRAWN INTO CHIP LOADING PORT PERFOWATION ON SIDE oF TUBE WARM Al OUTLET ~<—— DOUBLE GLAZED WINDOW OF KALWALL 62 VINYL O/ SS OPE PLA Na MIMIC oP 7 Vi Pr lL WTA Le Fo LININSS l AIR INLET +—____~ SOUTH FILLED TRANSPORT TUBES OF PERFORATED PUC PIPE | SOLAR DRYING SHED FOR WOOD CHIPS TROMBE’ WALL DETAIL Pggliag BLACIC PAINT MASONRY WALL <_< { DOUBLE GAZED GLASS WALL ty WOOD CHIPS WAIZM AIR ~ EXHAUST EYKAUST ae AUTOMATIC CHIP FEED GENERATOR GASIFIER TROMBE’ WALL <_—— +> SOUTH Ala INLET nl FINAL DRYING OF CHIPS WITH SOLAR AND WASTE HEAT OUTPUT: 8 900y4? PER YEAR SLED TRANSPORT 20 on CHIP éasona\S YEAR STORAGE) eet 2.8% EMPLOYMENT H ARVEST \ PER YEAR EMPLOY MENT INPUT: 20 YEARS MANAGE MENT (oear\<—/ BIOMASS EMPLOYMENT PLANTATION GASIFIER HARVEST | VILLAGE: ; AREA NULATO \GENERATO OUTPUT: b0 kw > OUT POT: 25 TONS oF 536,000 KWH WOODASH PER YEAR INPUT: PER YEAR 1.5 TONS ENHANCED PER ACRE ASH ASH MOOSE AND DISPERSAL STORAGE BEAVER HABITAT SLED TRANSPORT APPENDIX I MAP INDEX Seward Peninsula and Norton Sound Highlands Nulato Vicinity Constraints Maps 1. Wetlands and Poorly Drained Areas Vegetation Complexes Harvestable Wood Important Wildlife Habitat Endangered Species Sites Land Ownership a &® oO OR 6 6 Potential Historical/Archaeological Sites Combined Constraints 9. Suitable Harvest Areas Imigrook Lagoo™ Kotlik. Lagoon\- Proposed Cape Krusenstern National Monument} Krusenstern Lagoon)» Kotzebue Museum. Eskimo craft demonstration lative dances. Plane tours. Kotzebue 4th ar July Celebration. Beluga Derby. June-July Imuruk | Bn Kividigg y National Reserve | POV My. 4? ‘owpack, f they 4 J f- ZA Devitt, 75 - ShishmaretOSKchofl ‘ ShishnZAT Quer > 5, Arety —_f 3 Lay yf Ear ME 35 —s Ikpg 3 i eaeaun Serpentine Hot Springs ‘SHE ise = Kougarok Mt 2870; Taylor} ; Mes, : a gee) Pia pur ov fi Brevig MSS iE oy Oly cep : “Bunker Point Spe" fy ” entitle |B “lore f - Port C NSifivan a i New Igloo, <¢Marys Igloo: * Pil n A grim Springs : oh gM 2 ron abit ed by airship Norge on Mts-<- ra ae yighuaik nn Saimon Lake aceE 1926 “Pe Woolley Banat Casadepagas | Oregone ¥{BERING STRAITS King Island IVOK? Cape Douglas ng on beach 7 ickson afety Sound) 1 z ‘amps. Iditarod. : Dog Race, tival, June | Sintkg Solomon voy Sledge Is/and : ae 4 ing Nome gold rush National Wildlife Refuge . (Bluff Unit) ek Cape Krusenstern N= =) Yh Sheshalik Kotzebue’ ak Lakes Esch : ‘Goodhope FG %, ob Bay | NO PortS 9 cot™ ‘or ‘ort Safety Le ye | a At ge go tablished in 1900 by ee ae a eat ante ae™ * ‘my to maintain order Proposed Coastal Ro 0 rs 4183" 7 7%, Klery Creek txian: Cape Blossom ~ Hotham Peak '©44 Kotzebue ——~—-Baldwin } Pen. — Selawik Lake Olt. Nn! pe Seshant Point Sound — + PSRLIEA K falc t arsBuckland Bucky, ay Yoon, ae Besboro Island Noo rat o Egavik\_ nS owned Proposed Coastal National: Wildlife Refuge aes i Stuart Island Egg! ke Lagoon. rtheast Cape hulghat Mts 00k Cape Islands | peglt Michael, wre s ATR itarik SF x Oe SAS as i 669 mel he Sisters *Pikmiktalik | d Kobuk Valley Propose! set National Monument art \Onion Port, Great Kobuk Sand Dunes at | ioe Selawik per 2 *3307 tee _ uditare, | Jade Mts\, age 33511 tsambler ~ Pbukl =. of ountaing 2002 rf 7 Proposed __|i — VSelawik National a af sete Howkuk | y Proposed Rovu S t National Wildlize Refuge \ ofa va Moion SPP Totson Mt, bs ama “| Campo i = Grippletanding ss” ena = gRenniestanding 7 ; Dishkakat Gia oe. 8 ehh {= \ Sunshine A! 1 life Refuge | 3 | Mey Tolstoie. = = i a ig : . eS me \me Hurst, dy MI Me Hurst. Cloudy Ophiresa Surnile ' indy ake + nS » ” shna tslandw Big Hy ees 33 }—~___ i | 2 ) NULATO VICINITY MAP B: att ¥ 35 Big! tsland%- —— } gL0 WETLANDS AND POORLY DRAINED SOILS NOT SUITABLE FOR SUMMER ROADS MAP C2 VEGETATION COMPLEXES A ALDER B PAPER BIRCH BL BLACK SPRUCE/ACID FLORA S WHITE SPRUCE C BALSAM POPLAR/COTTONWOOD W WILLOW X SEDGE BOG HARVESTABLE WOOD - ALDER A IMPORTANT AND CRITICAL - WILDLIFE HABITAT / IMPORTANT SALMON /) SPAWNING RIVERS CRITICAL PEREGRINE FALCON NEST HABITAT SUMMER DEVELOPMENT PROHIBITED YEAR-ROUND DEVELOPMENT PROHIBITED NEW TOWNSITE J Endangered Peregrine Falcon Nest Sites \) Critical Habitat AQ from 15 April. - 1 August NULATO oy NULATO ISLAND KOO . exnensy Approximate Nest SES ; XXX Site LY-8 Nest Site Numbers , Way, BW /Y/// yy | Sy Ta f A] TL) |) BS | )» CN "y, WIM, Sy” OS / / y /- i Yy Wy foc / : LL NT] / LLY 5 of W/V A a l/h / e // Sf / } : LISS. J / / fy) Y SS, Vv / / //\ / A a 8 Sd / ff / ; LAL LN SY / / iv 7s f TE bul fb ff fffhffpppfpff. \ - a /ft/ C/ 777 TST V7 V7) 7777 7 B J HUM RAM ea f | UN IVALLALSL TY DVITL ILL? XN oi —Patey-|-——$ pe ae 7, VW //77PINY VAT AA] “fj Ce) 2 Syth i: / x A Nay i) / 5 Ui ALLL / ff ; AG aa / | ff ass / / fo NATIVE ALLOTMENT ==] APPLICATION VILLAGE SELECTION Sh} 7] MP ication /. / / REGIONAL SELECTION Qyrrisarion OTHER CLAIMS MAP C7 POTENTIAL HISTORICAL/ARCHAEO- LOGICAL SITES AREAS THAT MAY NEED TO BE SURVEYED tt ee fp. Pate Slough | eae | 1 COMBINED CONSTRAINTS MAP AREAS UNSUITABLE FOR HARVEST ee: isla ndio gL0 MOST SUITABLE . POPLAR/ALDER . WHITE SPRUCE . SPRUCE/POPLAR . SPRUCE/BIRCH . POPLAR HARVEST AREAS 600 AC 6,000 FT3/AC 500 AC 8,800 FT?/AC 400 AC 7,800 FT3/AC 500 AC 3,121 FT3/AC 300 AC 5,843 FT3/AC NULATO ENVIRONMENTAL ASSESSMENT CONTACT LIST Person Contacted Agency, etc. Phone Number John Ross Ak Dept of Transportation 266-1679 Bob Flint Ak Dept of Environmental Conservation | 274-5527 Stan Ungerford Ak Dept of Environmental Conservation | 465-2667 Marliss Prassee Community and Regional Affairs 279-8636 Jim Venard Forest Service 276-0939 Joe Marks Consultant 344-4279 Nan Evans Dept of Energy 206-442-2820 Jack Uton Doyon, Ltd 452-8251 Bob Averil U.S. Forest Service 276-0939 Jerry Tandy Bureau of Land Management 745-4271 Dean Argyle Institute of Northern Forests 479-7443 Roland Quimby Ak Dept of Fish and Game, Galena 656-1345 Doug Reeger DNR, Ak State Parks 274-4676 Dave Rosenau LGL, Fairbanks 479-6519 Ty Dillaplane DNR, State Historical Sites 274-4676 Bill Arvey ADGG Commercial Fish 344-0541 Ken Alt ADFG Sport Fish 452-1531 Dan Renshaw Consultant 276-3474 Clyde Peter Gana-a' Yoo Ltd 656-1294 Lou Fletcher U.S. Soil Conservation Service 276-2646 Roland Shank Tanana Chiefs Council Bill Gasaway Ak Dept of Fish and Game 452-1531 Skip Ambrose U.S. Fish and Wildlife Service 276-3800 David Mindell Bureau of Land Management 344-9661 55 The following persons are interested in receiving copies of the Nulato Environmental Assessment Report: Dean Argyle Institute of Northern Forests University of Alaska Fairbanks, Alaska 99701 Roland Quimby Alaska Department of Fish and Game P.O; Box?155 Galena, Alaska 99741 Clyde Peter Director of Lands, Gana-a' Yoo Ltd. Box 38 Galena, Alaska 99741 REFERENCES Community and Regional Affairs. 1972. Community Facilities Summary: Nulato. State of Alaska. 5 pp. Farr, Wilbur A. 1967. Growth and yield of well-stocked white spruce stands in Alaska. USDA, USFS Research paper PNW-53. 30 pp. Galliet, Harold H., Joe A. Marks, and Dan Renshaw. 1980. Wood to gas to power: a feasibility report on conversion of village power generation and heating to fuels other than oil, Vols. I, II, and III. AVEC and APA. 169 pp. Gregory, Robert A., and Paul M. Haack. 1965. Growth and yield of well-stocked aspen and birch stands in Alaska. USDA, USFS, Research paper NOR-2. 28 pp. Hartman, Charles W., and Philip R. Johnson. 1978. Environmental Atlas of Alaska. University of Alaska. 95 pp. Klinkhart, Edward G. 1978. Alaska's Wildlife and Habitat, Vol. II. ADF&G. Leckie, Jim, Gil Masters, Harry Whitehouse, Lily Young. 1975. Other Homes and Garbage. Sierra Club Books. S.F. 302 pp. McLean, Robert F., and Kevin J. Delaney. 1978. Alaska's Fisheries Atlas, Vols. I and II. ADF&G. Portola Institute. 1974. Energy Primer: Solar, Wind, and Biofuels. 200 pp. Reiger, Samuel, Dale B. Shoephorster, and Clarence E. Furbush. 1979. Exploratory soil survey of Alaska. USDA, SCS. 213 Pp. Renshaw, Dan. 1979. Coal and wood resources examination - mid- Yukon. AVEC and APA. 16 pp. 57 Seifert, Richard, and John Zarling. 1978. Solar Energy Resource Potential in Alaska. Institute of Water Resources. University of Alaska. 80 pp. Van Cleve, Keith. 1973. Energy and biomass relationships in alder ecosystems developing on the Tanana River floodplain. Arctic and Alpine Research Vol. 5, No. 3. 7 pp. Viereck, Leslie A., and Elbert L. Little Jr. 1972. Alaska Trees and Shrubs. USDA, USFS, Agric..Handbook No. 410. 265 pp. APPENDIX II a 59 POSSIBLE EFFECTS OF OTHER WOOD-ENERGY PROPOSALS A. Various Small Scale Operations Foreseeable small wood harvest operations in other AVEC villages besides Nulato could vary in any of the following significant ways: 2 Distance to harvest site = Topography/geology of the site Harvest of another set of tree species 2 Harvest at different tree densities Biota composition of harvest area Proximity to critical or unique habitats These possible variances from the Nulato harvest are seen as differences of degree and not kind. If the potential harvest sites for each village are evaluated with the same McHargian constraints analysis performed for Nulato, most of any possible negative environmental impacts will automa- tically be avoided. The choice of appropriate harvest technique and the use of reasonable forestry/conservation practices at the actual harvest site should preclude any serious or significant negative environmental impacts. The actual harvest techniques for each of these small (one or two village) supply programs would probably be rather similar to those selected for Nulato: small-scale and labor- intensive. However, this self-supply format would not be applicable for many villages along the coast and the wes- tern part of the interior. They are either too small or too far away from suitable stands of timber to harvest and return with their own wood. These villages have two choices: plant and raise their own crop, or buy their wood from another source. If the wood supply must come from elsewhere, two schemes of supply suggest themselves: 60 1) Each wood-deficient village would contract delivery from an upriver village with plentiful tree resources; this village would simply expand its yearly harvest operation to produce enough chips or cordwood to supply both villages, and barge the wood product downstream. If this extended harvest is done on a planned basis, it should not be too difficult to re- serve enough suitable woodland to insure a sustained yield at sufficient volume. If the expanded harvest scheme has been subjected to constraints analysis and the harvest itself is performed according to usual good forestry/conservation practice, then this ex- panded program should have no more negative en- vironmental impact than a harvest for the single village. 2) The wood-deficient villages receive fuel shipments from a central large-scale wood plantation: this is described in section 1.B. One other small scale format is worthy of discussion, and that is the possibility of individual village tree farms. Many of the coastal and interior villages lack a sufficient wood supply because the climate and soils of the area simply are not suitable for normal tree growth. However, it might be possible for many villages to prepare and plant a tree plantation of sufficient size to supply their energy needs on a sustained basis. Hybrid poplar has been suggested as a likely species for such a tree farm; 250 acres of this variety would give an annual wood yield sufficient to supply a village the size of Nulato (based on a ten-year rotation period). The many potential agricul- tural and economic difficulties of this scheme demand careful examination; for instance, the intense soil-nitrogen drain of this system might necessitate importing costly fertilizers, and thus the feasibility of the program would 61 be questionable. But it is an exciting concept and should be explored. Environmentally, such a tree farm should have no significant negative impacts, if the site is chosen carefully. Large Scale Operations Two possible large scale wood harvest operations suggest themselves: ; 1) A large, central wood harvest area, carefully managed and harvested with high-production, high-capital equipment systems. This would of necessity be a summer operation ‘to allow the product to be shipped downriver. This implies a flat site with soils well- drained enough to support permanent roads. A very large island on the middle portion of the Yukon would perhaps be the best site for such a harvest. These islands are often flat, well drained, fertile and pos- sessing high quality tree stands. Harvest on an island affords convenient access to water transport, protection from fire, and limits impacts of harvest/ vehicle operations on salmon spawning streams and critical habitats (these are usually not found on islands). The scale of harvest would be determined by the number of villages it served and by the size and density of the island's trees. Replacement of natural trees by hybrid poplar would allow high yields/acre, but this might be prohibitively expensive and unnecessary. Harvest at such a large scale - say, 300 acres per year - could easily cause soil damage and erosion. However, such a large operation would probably have access to professional and inten- sive plantation management. With reasonable manage- ment and care, the possible environmental hazards could be avoided. Assessment: the island itself 2) 62 would probably have a permanent change of ecological character, but this would not be environmentally significant. The reverse of the above operation may also be feasible: to barge the high-production equipment itself to various sites along the river. A seasonal operation, this equipment and a professional crew would proceed down the Yukon each summer and harvest a year's supply of wood chips for each client village along the way. The harvests would be at preselected sites for each village, each site being previously analyzed for environmental and mechanized harvest suitability. This scheme would have the same environmental impact as a local, small-scale harvest for each village, i.e., none, if the constraints/suita- bility analysis has been performed correctly. — It would seem that this idea might be the most economi- cally attractive large-scale format, since it would tend to maximize the use of the expensive machinery - and that barging tens of tons of equipment would be cheaper than barging hundreds and hundreds of tons of wood.