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ST. PAUL WATERWAY REMEDIAL ACTION AND HABITAT RESTORATION PROJECT Jerry K. Ficklin, Simpson Tacoma Kraft Don E. Weitkamp, Parametrix, Inc. Ken S. Weiner, Preston, Thorgrimson, Ellis & Holman ABSTRACT The Simpson Tacoma Kraft Company's St. Paul Waterway Area Remedial Action and Habitat Restoration Project consists of environmental improvement actions to remedy past and present practices to protect Commencement Bay and Puget Sound Water quality and restore fish and wildlife habitat. The project will correct sediment contamination by permanently capping this shallow area with clean Puyallup River sediments; ini- tiating chemical source control through raw material and process changes; installing a new secondary treatment plant outfall; collecting and providing secondary treatment for stormwater; containing wood chip spillage; and creating sub- stantial new intertidal habitat for bird and marine lifer The studies resulting in this action concluded that the project would create few adverse impacts and provide greater environmental benefits than other remedial action alterna- tives, such as dredging contaminated sediments, then land- filling or incinerating them. The project began in December 1987 and was completed in September 1988, after 18 months of planning and preliminary consultation with agencies, the Puyallup Indian Tribe, mill workers, environmental groups, citizens, and scientists. THE TACOMA KRAFT MILL AND NEARSHORE CONTAMINATION Simpson Paper Company Bought the Tacoma Kraft mill in late August 1985. The mill produces products common and essential to commercial and consumer use: paper (both bleached and natural), pulp, liner board, and similar materials. The mill has been operating since 1927, and was most recently owned by the Champion international and St. Regis corporations. The mill is located on Commencement Bay in Tacoma, Washington. It is built on a 57-acre peninsula of filled tidelands between the mouths of the Puyallup River and the St. Paul Waterway. The area was originally an intertidal mudflat between two forks of the mouth of the Puyallup River (Figure l). The original 1,750 acres of productive mudflats in Commencement Bay have been reduced to less than 100 acres through the bay's harbor development over the past 100 years. The bay 440

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441 is very shallow and calm near the mill, ranging in depth from a sandbar that is exposed at low tides to about a -20 ft mean sea level (MSL). For 37 years, the mill's wastewater was discharged without treat- ment. Its wastewater started receiving primary treatment in the 1960s and has received secondary treatment for the past decade. Its outfall was located on the bank of the former log pond, an area immediately offshore used to store logs. Logs were stored, handled, debarked, and chipped with few controls to prevent runoff containing woody debris from entering the bay. There was also chip spillage into the bay from the unloading of barges and the storage of chips immediately adjacent to the bay (Figure 2~. The sediments of Commencement Bay next to the mill have become contaminated with chemicals and with organic debris (Figure 3~. In the area near the outfall, chemicals toxic to marine life--such as phenol- ics, cresols, and cymenes--are the dominant contaminants. In this and other areas, logs, limbs, sawdust, wood chips, and similar organic materials blanket the bottom. Due to the organic and chemical contami- nation of these sediments, the general area was designated as one of the "hot spots" in Commencement Bay needing remedial action. The U.S. Environmental Protection Agency (EPA) has designated Commencement Bay's entire nearshore tideflats as a Superfund site on the National Priority List (Figure 4~. The nearshore log pond area near the mill was included in the site based on results from the Commencement Bay studies conducted by Tetra Tech, Inc. (consultants for EPA) and the Washington Department of Ecology (WDOE). PROJECT DESCRIPTION The objectives of the St. Paul Waterway Area Remedial Action and Habitat Resotration Project are to install an improved outfall. permanently isolate the sediment in an environmentally acceptable and cost-effective manner, restore and preserve intertidal habitat, and take preventative measures against future sediment contamination from the mill. Corollary objectives are to minimize dredging of contaminated sediment, preserve existing water dependent and harbor uses, use reliable and appropriate technology, and design the project to complement the nat- ural forces at work in Commencement Bay.

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446 The main components of the project are 1. new secondary treatment plant outfall with diffuser, 2. remedial action for contaminated sediments and habitat restora- tion, 3. source control by stormwater collection and treatment, chip con- tainment, and an ongoing chemical source control program, and 4. monitoring for the physical, chemical, and biological effective- ness of the implemented actions. These components are described below and illustrated in Figure 5. NEW OUTFALL The existing outfall for the mill's secondary treatment plant is permitted to discharge approximately 30 million gallons per day (MOD) through a discharge structure located immediately adjacent to the shore- line of Commencement Bay. This structure is within O to 12 ft of the water's surface, depending on the tide. The initial dilution from the existing outfall was estimated to be in the range of 2:1 to 5:1, the ratio of seawater to effluent. This low level of initial dilution allowed flocculation to occur, where dissolved material and small suspended particles combine. The flocculated material tended to sink and accumulate in the vicinity of the outfall, which contributed to the contamination of sediment there. Pilot plant studies determined that the minimum dilution required to prevent flocculation was approximately 20:1. Although the wastewater that emerges from the mill's secondary treatment system is well- treated, it is important for natural decompositional processes to continue by having good dilution and dispersion after discharge. The new outfall will take advantage of the dominant current pat- terns within Commencement Bay to move the diluted effluent offshore, away from the more sensitive shoreline environment. Adequate dilution, offshore movement, and monitoring will ensure that a problem is not simply being moved from one place to another. The proposed outfall will be moved from the old log pond area and extended 920 ft offshore from the northwest corner of the mill to a depth of about -70 ft MSL. The first 220 ft will be buried below the mud line for engineering and regulatory reasons, which will require dredging about 3,000 yd . This new location will enable the outfall to have a minimum initial dilution of 55:1, with the initial dilution normally expected to be 70:1 or greater. In addition, at this depth, location' and initial dilution, the effluent will be trapped in a layer of water moving offshore. The outfall planning studies found that other alternatives, including deeper outfalls with higher initial dilu- tions, provided less shoreline protection because they trapped in water moving shoreward. The new outfall will therefore eliminate the low dilution, thus pre- venting flocculation, and will ensure that the effluent is dispersed in an offshore direction that minimizes the opportunity for it to be

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448 carried back to shore. WDOE reviewed and approved the environmental studies and engineering plans for the outfall, which was constructed and placed into operation during February 1988. REMEDIAL ACTION Sediments near the mill can be viewed as having three general areas of contamination, with each area blending into the next (Figure 6~. 1. Area A contains chemical contamination with some organic deb- ris. Located near the old outfall discharge, it is about a five-acre area encompassing roughly half of the old log pond. 2. Area B contains a high level of organic debris intermixed with sandy, silty sediment, with some chemical contamination. The high level of organic material binds the sediment together, making it very cohesive. Area B is located on the southerly half of the old log pond, between area A and the St. Paul Waterway. 3. Area C is a blanket of wood chips on the bottom of the bay at the entrance to St. Paul Waterway, resulting from spillage of wood chips from the chip unloading facility. As noted above, the contaminated sediments were brought to public atten- tion through the Superfund designation of Commencement Bay and the sub- sequent Nearshore/Tideflats Remedial Investigation prepared by Tetra Tech under the direction of WDOE and EPA. Although hazardous waste conditions or public health threats do not exist, the sediments of the St. Paul Waterway are sufficiently contaminated to severely depress biological populations in the vicinity. Many of the chemicals identified by Tetra Tech in the remedial investigation were not those typically associated with a paper mill or the pulping processes. After detailed analysis conducted during the mill's source control efforts, it was discovered that raw materials supplied to the mill contained those chemicals. Studies have estab- lished that the highest level of chemical contamination is close to the old mill outfall and that the level of contamination decreases rapidly with distance from the old discharge point (Figures 7-14~. Organic debris, however, is a problem for marine life over a much greater por- tion of the area than are the chemical contaminants (Figure 143. Most of the chemical contamination is within the area of high organic con- tamination (Figure 3~. Permanent and significant reduction in volume, toxicity, or mobi- lity of contamination is a principal goal of a remedial action under Superfund. Remedial actions must be cost-effective and consider, among other factors, long-term potential threat to human health and the environment. Other impacts associated with excavation, on-site treat- ment, transportation, and ultimate disposal must also be considered. The St. Paul Waterway site is unusual compared to most areas of contamination in Puget Sound because there is no foreseeable need to dredge the site. The absence of a need to dredge the site allows the

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450 use of alternatives that involve capping in place. These alternatives could not be employed at locations that require dredging for new deep water moorage or maintenance dredging for navigational purposes. The proposed action will minimize the environmental impacts of stirring up the contaminated sediments. The absence of the need for dredging also offers an opportunity for habitat enhancement. The St. Paul Waterway site is also unusual compared with many areas of contamination in Puget Sound because of its shallow depth (less than 20 ft deep). Shallow water allows better control of dredging activi- ties as well as more observable monitoring. The shallow water also offers an opportunity to restore intertidal habitat. The proposed action will, without disturbing the contaminated sedi- ments, cover them with a cap of clean Puyallup River sediment. Puyal- lup River sediment is currently building a bar at the northeast corner of the area. Over 30 ft of deposition has occurred in this area over the past 30 to 40 years. With the surface currents generated by the old outfall discharge (30 MOD) no longer present, Puyallup River sedi- mentation in the area is expected to increase. This sedimentation would naturally cap the contaminated sediments: however, such a time frame is not acceptable. The remedial action will be tailored to the nature and location of contaminated sediment.. Area A will receive an 8- to 12-ft cap of clean Puyallup River sediment. During the outfall relocation and site prepar- ation work this past winter contaminated sediment from the chip barge unloading area and from the trench for the outfall line was placed in bottom depressions in area A and then covered with 2 ft of clean cover material to temporarily isolate the material until final cover is placed this summer [19883. This summer Area A will be covered by a 4- ft layer of clean sediment to chemically isolate the contaminated material. Another 4- to 8-ft of sediment will be placed on top of the remedial action cap to raise the elevation to intertidal depths. This cap will be contoured as a habitat enhancing feature and to work with natural forces (tides, storms, sediment accretion)(Figure 15~. Area B will receive a 4-ft cap to isolate the organic debris, lower levels of chemical contamination from biological activity, and provide new benthic substrate. This depth will provide an additional 25 per- cent of clean substrate than is normally considered needed for biologi- cal protection. Area C, the area covered with wood chips, will receive a 2-ft cap of clean material to provide new substrate for benthic organ- isms. The purpose of the Area C cap is not to isolate the bottom, but to provide a suitable base for new marine life. Finally, the entire area will be randomly strewn with boulders in order to provide not only a new habitat that varies with depth, but one which has a varying substrate. The habitat enhancement measures will create a new sandy, mudflat area similar to what has been lost on the outer edge of the Puyallup River delta over the past 100 years of har- bor development (Figure l). This restoration will provide valuable rearing habitat for anadromous migrants and juvenile marine species, as well as feeding habitat for shorebirds (Figure 15~. Current plans do not include intervention with the natural biological repopulation of the area. The expectation is that, given the high productivity of this

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J I M G f ~5@ u u ; _1 _ ~ ~ _2, ~ I ~ @ .' ~ ~ , u u 1 u 1 14- ~ .- ~2 go . · /, , . /~ ' / ^ . , . ;~,, ~~ a, ,- . ~7 use go// ~ /, . ,,/~., ~ 7~< . ~ ,~. am. . . . . · ~ . ~ . an. . , . # ~ ... # . .. a . . ". Ha: F>' ,-,' hi.' ... . . . E O C e ^ @ u @ @ 2- 1. 1- ~ @ @ ~ 1~ u u ~2 "- EXOTIC ~ ~ ~ ~ L~C1 7.~ ~ ~~ u at: . . _ HER r' ki @ 10 , \ ~ 11 ~ ' ~ K`" HILL I: __ BRIO ~H 3-E . ~ ~ ~M 0 ~ e ~ FIGURE 8 P-Cresol concentrat10n in sediments adjacent to the Tacoma Kraft mill (amphipod AET# 1~200 ~g/kg; benthic AET' 670 ~g/kg).

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K J I H ~ f E D C ~ ~ 1 · ~ SSB5 . n S2 t30 the . SSB t · 100 . · ~ ~ ,.& .~ i_ · 400 83 . 1,200 230 · . 1,200 ~0 SSB-2 ~ · 1,800 400 ,/ 360 . . i. 620 ' ~ 0 . 'I .. 18 lo' ·. .12 .~ 6200 u he ~ ~ lo' of. . ~ i,' ~ ~ ~ · ·/ ,;- ; 79 4,1 - ' . I' ' . , u ' , 8SB 3 · ~ ,'.',.,,, ~ ,. ~ :'.';. , . ; / :- - .. . . ,., ~ ,. . . t.. I: N , ~ .a N , , . . . " ',. he' lo' .~ N~ 9BPOO ~~ ! · ~OPOO "3POO, .. r' · 4 ~ .~ . · ~ . 1 Loo /; ' i . Cocoon - f l - EX~nNG ~ ~ /' . ~C ~' 3 1 PIER . ~ S 7 ~'''''l}r :, ' ~ ~ 11 \ TACOMA KRAFT MILL No - : Bat~try (~m Conloum) ~d on Mean Lower Low ~ht. (MLWV) ~LE IN fEE~ ~ ~ GRID ~A 0 100 ~ 2a) FIGURE 9 P-Cymene concentration in sediments adjacent to the Tacoma Kraft mil1 (amphipod AET, undetermined).

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K ~ I ~ ~ F · u . Sass ~ . u u 120 u SSB 1 . ~ 1tO ~30 · U U . ~ . .: 950 u . 280 u u U ~ 'A ~ ~ ~ :. SSB2— U ~e u .12 .10 300 u . . SSB3 'lo /f .— . . 240 . · . ~ . · . . by . . . ·. . . ,, · ,,400 U ~ ~ · · U uu- PIER .12 S. ~ u EXISTING OUTFALL _( l 890 u 1,600 .~ ~ ~ , - .~. .~e .t6 .~4 a 4 .. my; ;:-. o _ - : . . ~.130,, ~ ; mu .- . . . if-- · . . ~ . /:. . a: 1.'- . it. F: ... ' 1 .. a--. E D C _ 3 7, - u · ~ u u . . ..& FLU · Al TACOMA _' KRAFT MILL 4 5 7 9 10 J 11 N—: ~h~r~r (—tom C~re) ~d on Nban Lower Low W~er (MLIW) SCAL£ IN FEET ~ TRUE ~ ~H O 100 200 I~ FIGURE 10 Guaicol concen~cration in sediments adj scent to the Tacoma Kraft mill (~mphipod AET, 930 ~g/Icg).

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K J I '1 ~ F E D C B ~ a. ~0 260 340 230 ,, 1,0BO u .+ ~ ''a ,,& 210 ~ 'id 770 ~ ~ ~ ~ 1B ~ ~ ~2 ._- 520 ~ ~ ~ ~ ~ , 260 s-^ u 450 Sit ~ · ~ ~ ~ .~ ·" ·18 .12 .10 · u 130 290 u · · ~ ~ I. In. : . ' of. ~6 .. so 3 - 11 TACOMA KRAFT MILL .12 in- 4,~ u u 13,000 I' J 1 4' _ PIER 9 5 6 7 10 ) 11 No - : - ~~ - ~ Id) on Nban Lower Low W - r (MLLW) MALE IN FEET , , ~ ~ GRID AH O 100 200 FIGURE 11 Phenol concentration in sediments adjacent to the Tacoma Kraft mill (amphipod AFT, 670 ~g/kg).

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K J I ~ ~ F E D C ~ ~ · · SS~s ~ . u u 51 ~ ~ u SS~1 360 110 · ~ ~ ~ do · 300 U ' U ~ 'A · ~ .' ~ ~ .t,~ - ~ . I'. id. .— . ~ At,' ~~ {,.e I;S1~2 ~ 9, ,i ~ T , ~ . ~ 190 95,, . . I, . · i 1 ! · ~ do u .~ 1.400 .. ~ . 1SO ·a .. ." .. · .e · ~ c J 110 770 100 . .~0 1,400 U u u 9?POO .~2 ad ~— ~ . . -( ~ , ~-~.~ ' ' ' \ ' ,/ ;.',~,~2 :; , i,/: -''l-:--- ·- f, ;, ,', /.:- , . ,''.""'.''.'" 1: ~ ; I. of::, TOM ttFUFT MILL 14 PIER . ~ 1 9 S 7 10 J 11 N - : ~~)~ on Nban Law Lop Wed BALM SCALE IN FEET ~ RUE U NORM 0 100 200 '~ FIGURE 12 Nap thalene concentration in sediments adjacent to the Tacoma Kraft mill (amphipod AET, 29400 ~g/kg).

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K J I H ~ F E D C B ~ · · · · · · · · ~ · · 1 ~ ~ "~5e · ~ · · · · · 2 · ; 63 : 158 . ~ =. C . ~ ~ . . ~ ~ n 3 SSB-1 581 ' ; ~ ' ~ ~ ~ 1 1 4 , . . .. . . Bus ~ ~ ·. ;. ~ · ~ ;e ~~. ~ 1 ~ 5 _:' e' ') ~V ~ L', i.' .~ ; : ~ · ~ !}~ ' l 1 l.~ ~ W~ ;~ ~ . .' N - : ~~ (Mom at) on ~ Law ~ ~ BUM MALE ~ FEET ~ ~ ~ GRID a O 100 200 - FlGURE 13 Low-molecular -weight polyaromatic hydrocarbons concentration in sediments adjacent to the Tacoma Kraft mill (amphipod AET, 5,500 g~g)

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K .1 I H ~ ~ E D C ~ ~ i'' ~ i,! ; 1 .; j · · · · · · · ·",'tti~ ~ ~~ · · 1 · · · · · · · 41 '! ~ · · 2 ~ ',. : ., , , .! ~ , \ · · Hi,, ~ ~ · `~. 3 imp . . . . . . ; ~ ... . . . · #, ; . , i:. ~` ,:' I.: .. . . .... . ," ' i':' Note: Bat~ry (Bottom Conioum) on Mean Lower Low Water (MEW SCALE IN FEET ~ ~tRUE ~~ AH O 100 200 ~ FIGURE 14 Total volatile solids (percent isopleths) observed in surface sediments adjacent to Tacoma Kraft mill.

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459 Puget Sound estuary, marine life will rapidly reestablish itself under natural physical conditions (clean sediments, cobbles, boulders, and varying topography). SOURCE CONTROL The mill has undertaken a source control program on several fronts. Source control involves preventative action to reduce or eliminate chemicals or other substances that are potential pollutants. Much of the effort to date has been directed toward reducing or elimi- nating contaminants in raw materials brought to the plant. The other primary effort has involved changing manufacturing processes to control or reduce chemicals of concern. Examples of source control measures implemented are as follows: · Reducing the concentration of copper contaminating the mill's dominant source of purchased sodium sulfate (Vanillin Black Liquor), from 10,000 mg/liter to less than 10 mg/liter, repre- sents a reduction of more than one-half million pounds of copper to the mill each year. Eliminating a sodium hypochlorite stage from the bleaching sequence, by adding more efficient chemical-pulp mixers, and by adding an oxygen extraction stage, resulted in a 68 percent reduction in the aqueous discharge of chloroform. Ongoing measures that have significant source control benefits include replacing the 1937 vintage bleach plant with a new plant which, employing chlorine dioxide substitution for chlorine, state-of-the-art mixers at each bleaching stage, and scrubbers for air emissions, will effect an estimated 50 percent further reduction in chloroform emissions and reduce the total organic- ally bound chlorine emissions to well below standards recently established for Swedish bleached kraft mills. The source control program has removed well over a million pounds of pollutants from the facility on an annual basis. The source control program also includes control of woody debris. Operation of the newly installed chip unloading facility significantly reduced chip spillage during chip barge unloading operations. The con- tainment of wood chip fines (sawdust-sized material) will be improved this summer when fencing, improved conveyor cleaners, and water sprays have been installed. By the first of October 1988, all rainfall onto the facility will be collected and secondarily treated prior to discharge to Commencement Bay. Source control must be an intrinsic part of any remedial action effort to prevent recontamination.

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VERTICAL EXAGGERATION ~ 5 - Habitat Enhancement Profile 460 an, - -I - o --10 600 550 500 450 VERTICAL EXAGGERATION x 5 Aft \\1 ~ 400 350 300 250 200 150 100 50 0 Benn/Cap Layer Profile — _' -o ~ - ~ ~ NO VERTICAL EXAGGERATION Habitat Enhancement Elevation Cap Surface E - at on Organic Fill Elevation Existing Ebvatlon Final P - lo FIGURE 15 Typical profiles of perm and cap layers and final profile without vertical exaggeration. habitat enhancement

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461 MONITORING A comprehensive monitoring program has been designed for the St. Paul Waterway Area Remedial Action and Habitat Restoration Project to determine whether 1. the outfall and remedial cap are working as designed, 2. the area is becoming recontaminated from the capped sediment, the mill, or other sources, 3. marine life is returning to the newly created habitat, and 4. whether any problems develop that may ~ ~ require corrective action. The monitoring program will be directed by representatives from Wash- in~ton State Departments of Ecology, Natural Resources, and Fisheries; . Army Corps of Engineers, Fish and Wildlife Service, and Marine Fisheries Service; the Puyallup Indian Tribe; and —- -Cal ~ the U. S National Simpson Tacoma Kraft Company. The monitoring program will be most frequent during the first five years of the project, but will continue until contamination in the capped sediment has degraded to "acceptable" levels. The program will collect physical, chemical, and biological data to be compared to similar data collected from reference areas with in Commencement Bay. The program can generally be divided into three stages: preconstruction, construction, and post-construction. ~ ~ ~ ^ ~ ~-~ be to establish the biologi- The prin- cipal monitor~ng before construction will Cal and chemical baselines. Several types of construction monitoring will occur, including establishing sediment elevations, verifying proper sediment cover placement, and monitoring water quality to measure impacts occurring due to the remedial activities. Post-construction monitoring will be the most extensive. In addi- tion to detailed sampling near the new outfall diffuser, several differ- ent types of monitoring will occur within the remedial action area. That monitoring will focus on the physical integrity of the sediment cap by measuring depth of sediment cover and deposition of new sedi- ment, chemical analysis of core samples to ensure absence of upward contaminant migration, and biological monitoring to document repopu- lation of the area.