Effect of the Proposed Port Alberni Pulp Mill Expansion on Alberni Inlet Waters
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Effect of the Proposed Port Alberni Pulp Mill Expansion on Alberni Inlet Waters. by Michael Waldichuk GC 57 P11 55-02 .ffect of the Proposed Port Alberni Pulp Mill ;i3<bansion on Alberni Inlet waters. Br Michael Wiadieklik GC 57 P 11 55-02 Waldichuk, M. Effect of the proposed Port Alberni pulp mill expansion on Alberni Inlet waters 81331 04050921 C.1 Pacific Biological Station iebruary 3, 19514 OONT 3;25 Page Conclusions viecommendations Introduction 1 Characterirtics of il:ffluent 2 Unbleached Kraft 2 • iemi-bleachad Kraft 2 Croundwood 2 Hydraulic iiarker washwater 4 Oxygen DerEind of 6ffluont 4 Toxicity of .:,;ffluent 6 Location of the Outfall 7 Heferences 9 Conclusions Dissolved oxygen conditions in kaberni Harbour will be mainteined at a safe lovel under the proposed expansion of the Port itlberni pulp mill if the 3omt.ss liver discharge is controlled above 240 c.f.s. Toxicity of any of the effluent constituents should not occur if the river flow is maintained et the above discharge. tie commendations For the proposed expansion of the Port Ailberni pulp mill it is recommended theft (1) the Somass River be controlled at a discharge above .;40 c.f.s. to provide the dissolved oxygen necessary in the Alberni Inlet system; (2) the outfall be shifted at least 200 yarJs eastward from the present location so as not to present a toxicity fv - zerd in the Samosa :Aiver mouth; (3) if d3:edginc is conducted in the northeast end of the harbour the materiels should be used to Wild a dyke on the eastern tidal bank of the Jomeas aiver. This drlould further retein the pulp mill effluert until it is well diluted before it enters the Stimass ATect of the Proposed Port Alberni Pulp dill Zxpension on Alberni Inlet asters 'Michael Waldichuk Introduction In a conference at the MacMillan end Bloedel, Ltd., pulp m111 at Earmac, January 16, 19b5, Mr. 0.W.S. Locke outlined pleas for the expansion of the Port Alberni pulp mill. Present at the meeting were Mr. D.B. Loyd, Qhemical'ingineer with MacMillan and 3loodel, and Mr. M. Vialdichuk of the kecific jiological Jtetion. The proposel was presented again et the Pacific lologioel :-;tbtion, Jenuary 19, by Mr. Locke in the presence of Dr. J.P. Tully end Mr. .411dichuk. The plans call for an expansion of the present e30-ton per day un- bleached Kraft pulp mill to per der. In addition, a eroundwood sec- tion will be installed for the production of $00 tons per er: This cells for L50 tons of groundwood and 50 one per day of semi-bleeched Kraft pulp which will be token from the 330 tons of unbleached Kraft and pro- cessed further chemically. Mr. Locke requested to know What effect the dieeherve from such en expanded mill would neve on the waters of Alberni Inlet and what precautions would be necessary to avoid pollution. Mr. 6aldichuk indicated that certain characteristics of effluent from the proposed additions Should be provided in order that a suitable estimate could be made on the oxyome demsnd end toxi- city in the inlet waters. It was arced LLet these would be obtained. The present report is based on available data, information provided by the staff of MacMillan end Lloedel, Ltd., and literature on the subject. Many approximations hey° had to be made to predict the conditions which will result from the proposed expansion. Ohnrecteristics of Effluent Unbleached Kraft The cheracteri tics of effluent from unbleached Kraft pulp haVO been este.hlished in B.O.D. (biochemical oxygen demand) studies conducted by Hollister (1948), Tyler (1954) on the Port Alberni mill effluent and by others in American mills (Getm, 1953, p. 198). Table 1 gives the characteristics of the iort elberni mill including data supplied L: Mr, I. Petrie, November 15, 1954, compered to the nverege reported for U.S. mills by Gehm. In general, the low dissolved and suspended solids end low 8.0.D. in the Port Alberni mill effluent rate very favourably with the oversee U.S. mill as far us pollution is concerned. The pH is high but is rapidly reduced on discharge into sea water with its lerge buffer capacity. Unbleached Kraft mill effluent is in- jurious to fish mainly because of its high oxygen demand, but there is no doubt that it is also toxic directly ellen in high concentration just as in bleached Kraft effluent. Semi-blenched Kroft This pulp produces en effluent similar to that of the unbleached Kraft, but contains, in addition, a fraction from a dhlorinetion bleaching process. The characteristics of this effluent from semi-bleached operation at the Harm mill wore determined by lir. Loyd. They are given in Table 2. composite sample is usually characterized by as low pa. Groundwood Effluent from groundwood pulp consists of washines from pulp derived from mechenicnlly ground wood without any chemical treatment. Table 3 gives the characteristics from enelysis of Elk Fells effluent samples by Mr. Loyd. 'eastes would consist chiefly of finely divided hemlock, Douglas fir and cedar that es- cape in the process of disinteer , tion. It has been assured that this loss will - 3 - be small because of efficient screening processes to be installed in the new plant. eccording to 'estfell (ater duality Criteria, 1952, p. 261), a finely divided wood, like pine, contributes a grinding effluent that is toxic to aquatic organisms. This apparently depends largely on the type of wood be- ing used and concentrations, because Knight (1902) found that trout lived for two weeks in water heavily polluted with sawdust, with no trace of injury. iTevious assertions tat fish may be killed by clogging of the gills withers- pended particles heve been disputed by 'ard (1938). He points out that gills became choked with debris only wean the fish ere weakened by other causes and are already dying. In experiments performed on sawdust, Knight (1907) found that a yellowish brown eolution Highly toxic to fish appeared above fresh sewdust in weter. Apparently there is a repid leaching action by water which dissolves out soluble substances in wood oells. The sawdust becomes harmless otter some tine. in addition to the toxic meterials, organic constituents in the wood cells have e high oxygen demand which reduces the dissolved oxygen content of the water. The experiments were performed in the laboratory where high con- centrations of sawdust were meintained. In nature such conditions were seldom found. In addition to the groundwood effluent as such, there is the waste from the groundwood bleaching process using zinc hydrosulpeite. It has been sug- gested that in the proposed newsprint mill the amount of hemlock, which gives the characteristic reddish colour, will probably be email so that little if any bleaching with "zinc hydro" will be necessary. e process of blueing and hydrogen peroxide hevine negligible pollution qualities will be likely suffi- cient to bring the pulp up to the required colour standard. However, in the tentative pions the zinc hedrosulehite process is included and will be given due eonsidemtion here. zones (1938) reports that in water with 50 ppm of calcium, 2.0 ppm of zinc is not toxic to fish. .ith concentretien of calcium reduced to 1.0 ppm the zinc is ':zle in concentrations as low as 0.3 pm owing to the removel of the antagonistic action of calcium. Sea water contains about 400 epm of calcium so that it can be expected that the lethal limit of zinc in Alberni eerbour is in the neighbourhood of 2.0 ppm. eccordine to elles, eestfall and 7:11is (1948) "zinc compouns seriously affect the gills of many fishes causing incree7oe secretion of mucus and the production of metal-organic com- bination in and on the gills which causes death by respiratory difeiculty end anoxia". hydraulic Berker wash eeter Barkers introduced into tee nee pleat will contrieute a certein teeeeeei amount of suspended materiels and dissolved organic substances tweaked out of the bark and wood into the wash water. however, it has been pointed out that the amount of barker effluent will not be changed from that at present inas- much as only weod from the existing sawmills will be diverted to the pulp mill. kMrk extracts such as tennins are toxic but only when in fairly high coneentration. epperently the effect of e.O.L. of bark extracts is of greater significance and experiments by £night (1907) showed that bark solutions ehen aerated supported fish life as well as any normal water. Oxygen Demand of ffiuents The oxygen depend of constituent fractions of the total effluent will be considered here individually to arrive at an estieete of the total oxygen demand imposed on ulberni inlet water. eUxine of frections should tend gen- erally to reduce the D.O.E. For the 330-ton unbleached Kreft mill at 28,000 U.S. gallons of effluent per ton and a 5-day B.O.D. of 150 ppm, oxygen demand am 330 tons x 28,000 x 8.33 lb x 150 ppm day ton gal es 11,550 lb, per day 106 The effluent from the semi bleach proeese has an oveeage 5-day B.O.D. of 45 ppm (Tyler, erogress keport, epril 22, 1954). The oxygen demand for a 50-ton per day production at 38,00n gallons of effluent per ton would be 5t ton x 38,000 x 8.33 lb x 45 ppm ton gal g. 712 lb per day. 106 The B.O.D. for groundwood effluent is unkown but is presumed to be nearly the same as that for unbleeched graft mill effluent.