1. Lincoln's sawdust pulping process is described in the following sequence:

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1 LINCOLN PULP & PAPER CO. INC. SAWDUST RECOVERY OPERATIONS 1. Lincoln's sawdust pulping process is described in the following sequence: A) Sawdust from the typical sawmill is blown from the saw blade area into piles on the ground. Maine has many piles in places where the sawmill has long since been moved. In contrast, the sawdust bought by Lincoln is blown into specially designed collection bins to prevent contamination. It never touches the ground. Lincoln's collection system provides trucks which back under the bins for loading on a regular schedule. The "possum belly" trucks are specially designed to maximize the allowable load of sawdust they can carry, since it is a light, bulky material. The trucks are covered to prevent blow-out of the material during delivery, and are designed for automatic unloading at Lincoln's mill. Twenty trucks are constantly in this service. B) Lincoln's storage area has several features which are specially designed and unique. The sawdust after leaving the delivery truck is distributed by overhead conveyor to a pile 480 feet long and 40 feet high. A tunnel runs under the pile the entire length and a conveyer screw extends from each side of the tunnel to the edge of the pile. The conveyor screws are on tracks so they traverse the entire length of the pile, along its bottom, drawing sawdust onto twin conveyor belts in the tunnel which carry it to the screening area. The diagram attached shows how the system works. Lincoln's was the first in North America. The overhead conveyor is operated from the pulp mill using television monitors so that it can be made to dump anywhere on the pile. The screw conveyors are managed in the same way, and they are constantly mining out sawdust at the bottom of the pile. The purpose of this is to obtain a consistent mixing of the material, since sawdust from the various mills differs in character and nonuniformity of the pulp would otherwise result. Excellent control of the filling and mining operation is also required by the fact that when sawdust is piled 40 feet high and packs, high temperatures are reached at the

2 pile's interior. These temperatures can exceed 500, setting the pile on fire. This does not occur at Lincoln because of the unique filling and mining arrangement and the controls that go with it. * Another completely unique feature of Lincoln's storage is its air-foils. High winds blowing between the 15* space below the overhead conveyor and the top of the pile creates an air jet by the Benouli effect, which tends to strip the sawdust off the pile and propel it for considerable distances. Professor Barren, head of the Aerodynamics Department at MIT worked with Lincoln's engineers to develop air-foils to fill this space, creating a "wind-jump" protecting the pile. C) After leaving the storage area, the sawdust passes over screens designed to remove particles that are too big or too small. The upper limit is determined by passing the sawdust through a screen with a 4 mesh per inch configuration as described in the answer to question 2. D) Lincoln's pulping of sawdust is again highly specialized. The sawdust pulp is cooked by itself in an M&D continuous digester, while hardwood chips made from logs are separately cooked in a Kamyr continuous digester. Seven mills in the United States are producing pulp from sawdust. Of these, five use M&D digesters and two use the older Pandia digesters. The standard continuous digester or batch digester can not be used to cook sawdust, and a mill so equipped will not make this product. The M&D digester was chosen by Lincoln as the only reliable method of cooking sawdust. A 332 sawdust 67Z hardwood blend is the constant standard for Lincoln and the operating rates of the two digesters must be maintained with very high accuracy relative to each other. This is done by computer hardware and software developed for this purpose. No other mill in the United States operates with a consistent pulp blend made as Lincoln does it, using waste sawdust as a constant basic component of the pulp. The 33Z-67Z blend is processed through the pulp mill as a blend, and that same blend is used by Lincoln to manufacture tissue. *From time to time abondoned sawdust piles catch on fire The worst of these fires is of the type described above, caused by spontaneous combustion, where the pile burns from the inside creating a cavity at high temperatures. Any weight on top can cause collapse with great danger

3 E) A final special feature of Lincoln's sawdust operation is the sizing of its recovery boiler. In making kraft pulp, black liquor is formed containing chemicals to be recycled and wood binder material to be burned in a recovery boiler. The capacity of a recovery boiler is measured by the quantity of black liquor that it can process. Hardwood kraft pulp produces 2,800# black liquor/ton of pulp. Softwood kraft pulp produces 3,300f black liquor/ton of pulp. Softwood sawdust pulp produces 4,100* black liquor/ton of pulp. This means that a recovery boiler making softwood sawdust pulp has to be one and one half times as big as a recovery supporting the same tonnage of hardwood kraft pulp and 125Z of the recovery for an all softwood kraft mill. If a hardwood kraft mill running at capacity and with its recovery in balance with the mill wanted to go to all softwood sawdust, it would have to reduce its output by over 302 due to recovery boiler limitation i.e., from 1000 tons to 680 tons. Such a reduction would be economically unthinkable. It is doubtful that such a mill could break-even under 80Z of capacity. This means that kraft pulp mills currently making softwood or hardwood pulp from chips are highly unlikely to convert to sawdust pulp even if they had a suitable digester. Furthermore, since the recovery boiler is the single most expensive investment in a pulp mill, it would be unlikely that any balanced kraft mill would replace its recovery boiler with a bigger one so as to be able to run sawdust. As a point of reference, a greenfield bleached softwood kraft pulp mill would cost about $800,000 per daily ton of production, or $800,000,000 for a looot/d mill. Over $100,000,000 of this would be for the chemical recovery system. Lincoln's recovery boiler was built with enough excess capacity for normal operation of the entire pulp mill at a 33Z-67Z blend rate. This is completely unique in this industry

4 2) The sawdust used by Lincoln is from spruce, fir and pine logs which has been recovered from unaffiliated sawmills in the state of Maine. These sawmills include the following: Moose River Lumber Sebec Lumber Diamond Occidental Forest, Inc. Buy Freil and Sons Levesque Lumber Dirigo Lumber Pinkham Lumber Strong Lumber Haskell Lumber Cousineau Lumber Approximately 802 of the material is in the form of sawdust and 20% is in the form of shavings. 502 of the particles are of a size that will pass through a number 4 mesh screen (4 mesh/inch). The particles would have an average diameter of less than.185 inches. 3) With respect to alternative outlets for sawdust in Maine, we do not believe that any sizeable demand exists other than Lincoln. There are a number of wood to energy and cogeneration boilers in the state of Maine, which in theory could utilize some sawdust as fuel. Indeed Lincoln is currently building such a biomass boiler. Unless special, costly design changes are made in these boilers, the quantity of small particle size material such as sawdust that can be burned is severely limited. The operator of at least one such boiler (Bio Energy in Chester, Maine) has discounted the purchase of even small quantities of sawdust for this reason. There are no fiberboard mills in Maine that might consume the material. Finally, a small amount of sawdust is used for animal bedding in the southern part of Maine, but the quantities involved are believed to be small and demand fully satisfied by the limited quantities of sawdust available in that area of the state. The environmental problems caused by sawdust piles are essentially two fold. If they are left to rot in place, the leachate will seep into nearby water bodies and wet lands or into the groundwater supply. Since sawmills have been typically constructed next to water bodies, the decaying sawdust represents another source of BOD. Because of these and other problems, the Maine DEP has issued regulations severely restricting the siting of sawdust piles and governing their operation. Second, the traditional method of disposing of sawdust has been to burn it in open incinerators. Without the proper pollution control equipment, such practices result in air quality degradation and are prohibited

5 It should be noted that the depressed condition of residential construction has had a severe effect on these sawmills. Of our 10 suppliers, one has closed down, one operates intermittently and the others run at about half speed. The total delivered cost to Lincoln of waste sawdust was $2,565,000 in 1988 and $2,623,000 in Without this income, they very likely could not be in business. The mills employ about 625 people and are supported by more than that in the woods and in trucks. 4. Lincoln's recovery and use of sawdust benefits the environment in several ways. A. Lincoln annually collects approximately 200,000 tons of sawdust. That is equivalent to 28 million cubic feet each year. As indicated above, there is no other use for this quantity of material. (Power boilers are not normally designed to burn small particle sizes. The market for animal bedding is extremely limited). As a result, the only alternative for the sawmills has been to leave it in piles where it presents a solid waste problem, or consume it in burners which creates an air pollution problem. Because Lincoln collects the entire sawdust generation from the principal sawmills in Maine and has done so for 13 years, a major solid waste problem has been averted. B. Were Lincoln not to utilize the sawdust, it would be purchasing approximately 100,000 cords of softwood logs. At an average growth of one half cord per acre per year, that is equivalent to the annual softwood growth from 200,000 acres. There have been growing concerns in Maine about the adequacy of the softwood fiber resources and the environmental consequences of overcutting. Lincoln* sawdust usage is an effective response to these concerns. 5. If sawdust were included as a permitted recovered material, it is probable that few, if any, other pulp producers would qualify. We believe that modifications to the regulation can be written to limit the definition of sawdust to true waste material and further that Lincoln may be the only North American producer that would qualify

6 As noted earlier, Lincoln manufactures bleached Kraft pulp from a blend of 1/3 sawdust and 2/3 hardwood chips. The sawdust is processed in an M & D digester which is specially designed to "cook" small particle sizes. The typical digester found in most pulp mills is not capable of handling sawdust. To put this in perspective, there are 124 Kraft pulp mills in the U.S. (1) of which 104 produce bleached kraft pulp (the others produce unbleached pulp for use in linerboard, paper bags, etc.). Of these we believe there are only 6 others that are capable of pulping sawdust, all but one in the Pacific Northwest. Among these seven, Lincoln is unique because of a combination of four factors. A. Lincoln's sawdust particle size is small. The average diameter is less than.185 inches, small enough to pass through a 4 mesh/inch screen. We believe the average particle size on the West Coast may be considerably larger due to coarser sawmill blades and the use of undersized chips. B. Lincoln purchases a material from unaffiliated sawmills which would otherwise not be recovered. In other locations, we believe, the sawmills manufacture the material as another product to be furnished to the pulpmill along with chips. C. Lincoln is committed to sawdust for a significant proportion of its fiber whereas the other mills are limited to a much lower share, generally With one exception, only Lincoln is capable of producing a pulp with 30Z recycled content. D. Lincoln relies on the sawdust, which is derived exclusively from softwood trees, to upgrade the strength of its pulp. All of the other mills blend the sawdust with softwood chips which means that the sawdust effectively degrades the strength of their pulps. As a result, while Lincoln must include the sawdust to attain the desired pulp strength, the other mills are not similarly committed. (1) Lockwood - Posts Directory of the Pulp, Paper and Allied Trades, 1989, Miller Freeman Publications, Inc., New York 7/2/90-6 -

7 EXHIBIT TO QUESTION 1

8 U.S. BLEACHED KRAFT HILLS WITH SAWDUST PULPING CAPABILITY LOCATION OWNER TOTAL BLEACHED PULP CAPACITY (TPD) (1) ESTIMATED SAWDUST POTENTIAL PULP CAPACITY (2) FINISHED PRODUCTS (1) COKMENTS(2).» Clatskanie, OR James River Newsprint and groundwood specialties, towel and tissue, market pulp Mill also produces 325 TPD of groundwood pulp Halsey, OR Pope & Talbot Market Pulp 50% of pulp sold to James River for towel and tissue. Digesters also process chips. St. Helens, OR Boise Cascade Printing and writing, envelope, kraft specialties Sawdust digester also processes internally generated screenings (undersized chips) Cams, WA James River 930 N/A Bleached and unbleached kraft converting, tissue, envelope, tablet Wallula, WA Boise Cascade Corregated medium, market pulp, printing and writing Lewiston, ID Potlatch Folding cartons, file folders, milk cartons (1) Lockwood-Post Directory of the Pulp, Paper and Allied Trades (2) Lockwood-Post Directors, supplies estimates, company contacts, mill visits

Should Whole-Tree Chips for Fuel Be Dried Before Storage?

United States Department of Agriculture Forest Service Forest Products Laboratory 1 Research Note FPL-0241 Should Whole-Tree Chips for Fuel Be Dried Before Storage? By Edward L. Springer Abstract Whole-tree