DISPOSAL OF SOLID ALUMINUM PROCESS WASTES

                 IN THE OCEAN
                      by

              D» J, Baumgartner
               R. J, Callaway
               G. R. Ditsworth

 National Coastal Pollution Research Program
Federal Water Pollution Control Administration
     Pacific Northwest Water Laboratory
            200 S. 35th Street
           Corvallis, Oregon 97330

-------
                          CONTENTS









  I  Introduction	....I...,,....*..*....*...   1




 II  Material and Dumping Schedule ...,...«.	   1




III  Pollutional Aspects	....»,   6




 IV  Possible Pollution Problems




     A   En Route	.,.....,....,   7




     B   At Ocean Disposal Site .„.,......,	   8




         1   Transport with Current	  10




         2   Bottom Accumulation	  11




  V  Summary and Recommendations	  13

-------
                  Disposal of Solid Aluminum Process Wastes




                             in the Ocean






I,  Introduction




    Reynolds Aluminum Company, Longview, Washington, has requested




permission from the Portland District, U. S. Army Corps of Engineers,




to dump solid aluminum process wastes at one of three localities in the




Pacific Ocean near 125° W. longitude, 46° N. latitude.  These sites




are approximately 40 miles off the mouth of the Columbia River and are




shown on Fig. 1, which is an overlay from U.S.C.G.S. chart no. 6002.




    This report discusses the probable disposition of the material to




be dumped.






II. Material and Dumping Schedule




    One-hundred seventy-five thousand tons of accumulated material,




Kelly residue, is to be dumped at a rate of 1000 tons per day within




a one-year period beginning about July 1, 1968.  This material is




generated at the rate of 18,000 tons per year and the company proposes




to dump each annual accumulation within a one-month period.




    In addition to the Kelly residue, the company wishes to dump another




material, lime mud, generated at the rate of 8,600 tons per year, within




an 8-day period each year at the 1000 tons per day rate.




    Detailed chemical and physical characteristics of each material




as provided by the Corps of Engineers are given in Tables 1, 2, and 3.

-------

-------
                        TABLE 1

              DESCRIPTION OF WASTE MATERIALS
Chemical
Component
Carbon
Water
A12°3
CaF2
Fe2°3
SiO,
Material:
Analysis
Wt. 7,
35
12
35
3.5
8
1.5
5
Kelly Residue
Sieve
Tyler Mesh
65
100
150
200
Pan
Size
Cum, 7« Retained
6.0
13.7
22.6
29.3

             100


Particle Density:  168 pounds per cu. ft. (Sp. Gr. - 2.7)

Settling Rate:   3.5 feet per hour in calm sea water at 50°F.

Location of Stockpile:  SE end of Reynolds Metals Company
    property, Longvlew, Washington, between spurs of Northern
    Pacific Railway

Size of Stockpile as of 7-1-67:  175,000 tons

Rate of Generation:  18,000 tons per year

Proposed Dumping Schedule:  1,000 tons per day; 20,000 tons per
    month until stockpile is depleted, beginning about 7-1-68
    and ending about 7-1-69.  Thereafter, the annual generation
    of 18,000 tons can be disposed of in less than one month at
    1,000 tons per day.

-------
                              TABLE 2

                           KELLY RESIDUE
LABORATORY ANALYSIS
WEIGHTED VALUES
Sample

1
2
3
4
5
6
7
8
9
10
11
12
13
CN~,
Total
1.06
1,78
2,20
1,63
1.67
6.38
3.12
4.44
29.48
3.52
2.68
1.65
1.10
ppra
Free
0.89
1,23
1.94
0.62
0,59
0.84
0.90
3,10
13.38
0.66
1.32
0.57
0.53
Area
Represented,
Sq» Ft.
9,375
8,200
7,025
7,250
15,025
10,000
10,000
10,010
10,060
10,000
14,625
10,125
7,850
Fraction
of
Total
Area
0.0675
0.0590
0.0506
0.0522
0.1082
0.0720
0.0720
0,0721
0,0724
0.0720
0.1058
0.0729
0.0565
Weighted Values,
ppm CM"
Total Free
0,07155 0.06008
0.10502 0.07257
0.11132 0.09816
0,08509 0,03236
0.18069 0,06384
0.45936 0.06048
0.22464 0.06480
0.32012 0.02235
2.13435 0.96871
0.25344 0.04752
0.28354 0.13966
0,12028 0.04155
0.06215 0,02995
(Avg. 14-
17 to find
A)
14 103.07
15 98.12
16 78,50
17 2.47
Avg., A 70,54
Sura of 1-13+A



47.89
44.48
49.87
0.57
35.70

                              9,375
                            138,920
  0.0675
  1.0007
4,76850
9,18
2.41330
4,12
                                                       Total
                      Free

-------
                        TABLE 3

             DESCRIPTION OF WASTE MATERIALS

                  Material:  Lime Mud

 Chemical Analysis           	Sieve Size

Component      Wt. %         Tyler Mesh    Cum. % Retained

 CaC03          90               65             4.4

 CaF2           10              100            16.4



               100              150            53.8

                                200            88.7

                                Pan            100.0

Bulk Density:  88 pounds per cu. ft.

Particle Density:   187 pounds per cu. ft. (Sp. Cr. = 3.0)

Settling Rate:  3.7 feet per hour in calm sea water at 50°F.

Location of Stockpile:  Immediate east of Kelly Residue stockpile

Size of Stockpile:  zero, as of 7-1-67

Rate of Generation:  8,600 tons per year

Proposed Dumping Schedule:   1,000 tons per day for eight con-
    secutive days each year, beginning about 7-1-68, not on the
    same days that Kelly Residue is dumped.

-------
Ill,  Pollution Aspects




      The cyanide portion of the Kelly residue appears to be of major




concern from pollutional considerations.  Little  information concerning




tolerable concentrations in sea water has been found.  However, McKee




and Wolfe (1963) cite opinions of various investigators that wastes




should not be discharged to ocean waters when the resulting HCN con-




centrations will exceed 0.05 mg/1.  This concentration is equivalent to




,,0488 mg/g in sea water at 32°/oo salinity and 10°C.  Cyanide  ions in




water react, depending on the pH of the system, to form undissociated




hydrogen cyanide (HCN).  Since this is the form in which the ion is




the most toxic, it is appropriate to consider toxicity expressed in




relation to the HCN concentration.  At a pH of 8, approximately 6»7%




is in the form of a cyanide ion (CN~).




      We will presume for the purpose of this analysis that this is to be




the maximum allowable concentration of HCN in the area of the discharge




of the waste materials.  Table 2 shows that the weighted average con-




centration of free cyanide ion in the accumulated stockpile of Kelly




residue is 4.12 parts per million.  However, because of the rather large




variability in the analyses of the various sections of the stockpile,




we would prefer to use for this analysis the average of four analyses




in one section of the stockpile which amounted to 35,7 ppm of free CN"o




While this is a considerable over-estimate for the pollutional aspects




of the stockpile as a whole, it is not unreasonable to use a value this




high to represent possible hazardous conditions of any one particular




large load of residue.  A 1,000 ton barge load would then contain

-------
 71,4 pounds of free CN".  The equivalent  in  terras  of HCN would be  74




 pounds „






 IV.  Possible Pollution  Problems




     A.  Enroute




         Chip barges  in  the Yaquina River, petrochemical tankers in the




 Ohio River, and chlorine barges in the Mississippi River have suffered




 accidental spills or been sunk, with subsequent release of the material




 to the waterway.  There  is a distinct possibility  that the same type  of




 accident could occur with the transport of the Kelly residue material




 down the Columbia River  to its ultimate disposal site in the ocean.




 The resulting pollution  problem would appear to be more serious for




 this situation than that resulting from the  intentional dumping of the




 barge at the disposal site.  Assuming a relatively low flow of the




 Columbia River of 123,000 cfs, the uniform distribution of a sunken




 barge load of 1,000 tons over a period of one hour would produce a




 concentration of suspended solids of 86 mg/1.  Similarly, the concentra-




 tion of HCN would be about three mg/1.




         A more appropriate and precise analysis is provided by a




mathematical model of the lower Columbia River considering the effects




 of diffusion as well as advection and considering that the barge contents




would probably be dissolved and redistributed over a much longer period




 of time.  The resulting pollution problem would be most serious at Long-




view, Washington, and would diminish as the accident site approached the




 ocean.  Unfortunately, the limit of our mathematical model at present

-------
                                                                     8






is mile 20, and the analysis is carried out for an accidental spill at




that location.




         Assuming that the barge contents are distributed uniformly for




a day and confined to the flow through the south channel of the river




(see figure 2) the suspended solids concentration would be about four




mg/1, and the concentration of HCN would be about .14 mg/1.




         Under similar conditions, but assuming the complete flow of the




Columbia River participates in the distribution of the wastes, the con-




centration would be about .6 mg/1 of solids and .02 mg/1 of HCN.




         Because of the rapid flushing of the Columbia River at this




point, these concentrations will be localized to within a few hundred




square meters for a period of 1 to 2 hours.






     B,  At Ocean Disposal Site




         Currents in the area are poorly defined and influenced by wind




and local bathymetry.  Generally, surface currents are northerly in




the winter and southerly in the summer.  Average velocities of these




currents vary from 10 to 20 cm/sec and 5 to 20 cm/sec respectively.




(Budinger, Coachman and Barnes, 1964).




         Stevenson (1966), using parachute drogues,  measured subsurface




currents off Newport, Oregon from 1962 to 1965.  Mean current velocities




in this area were found to be 9.9 cm/sec at 0-10 meters depth, 6.2




cm/sec at 40-60 meters depth, 4.8 cm/sec at 75/150 meters depth and




6.2 cm/sec at 200-250 meters depth.  The mean direction of these




currents was south-southeasterly.

-------
      /Ji f : i v x "•"-- *' rv
     v' MirK,)' --AxV
     'T^V. $  <\  ;^v\
     -lr  /?^   >/
   >X ^fjflU^
 ^•/fo^^  /r
^p?f  ^
"\ ^V^ /-O/
        x/
• rs'
/ ^^//
    " >/



     I-
^•^>
j-y  /

    \
    v
    •#"
   —X.*!

 ^--4
  #1/330
                        r\j

-------
                                                                       10
         No specific information has been found about the nature of the




current at the much greater depth found at the suggested disposal site.




The current regime on the ocean floor will have an effect on the




accumulation of solids if they reach the ocean floor due to sedimenta-




tion, while the surface currents will have an effect on the initial




distribution of the material as it is dumped from the barge.






         1.  Transport with Current




             When the barge contents are discharged at the disposal




site, possible pollution problems may result if the material is finely




divided and evenly distributed so that the relatively high surface




currents will transport the material, perhaps toward the beaches.  If




for some reason all of the CN" were dissolved by the surface waters and




retained in the top two meters, distribution over 360,000 square meters




would be required to reduce the potential HCN concentration to below




5 mg/1.  This represents a circle of radius 340 meters.  This is the




result which might be expected if sedimentation were governed by the




individual particle settling rates as indicated in Tables 1 and 3.




However, this behavior is not expected, as the material most probably




will be compacted into various size clumps.  While there is no exact




method of analysis for the resulting sedimentation rate, guidance can




be provided by considering two cases which represent the range of




likely situations.  One is to assume the material is a slurry and




settles like a liquid of the same bulk density; the other is to assume




all of the barge contents act as a single clump of material which




settles in a discrete fashion.

-------
                                                                   11






             Assuming the material acts as a slurry, it will initially




settle with a high velocity due to the large volume of dense material,




As it proceeds downward the turbulent boundary between the slurry and




the ambient sea water will cause mixing of the two and the creation of a




wide9 less dense, "cloud" of slurry.  As the cloud continues to




settle, it will be further diluted by sea water and will decelerate-




At a depth ZMAX the cloud will become so dispersed, and the downward




velocity will be so degraded, that settling will be determined by the




mechanics of the individual discrete particles.  ZMAX has been cal-




culated to be 390 meters, and the calculated time of travel to this




depth is 99 seconds, according to the method of Morton, Taylor and




Turner (1956),




             If, on the other hand, the mass acts as a large discrete




particle, it will fall with a constant velocity through the water




column until reaching the bottom pass ZMAX in 16.5 seconds.  Its




average settling velocity will be 23«6 cm/sec.




             In reality, the material will probably settle in an inter-




mediary fasion between the two discussed,




             Surface currents have the most effect in the cloud analysis,




causing increased dilution, and will possibly transport some particles




away from the main flow of the cloud, which would remain essentially




vertical,




         2,  Bottom Accumulation




             If the barges can dump within a one-mile radius of the desired




dumping location, the most concentrated possible result on the bottom

-------
                                                                       12






will be an accumulation  of  solids with a  one-mile radius.  Under




this assumption  the present  stockpile of  Kelly residue would be




represented by an average area distribution of 43 pounds per square




meter.  The annual production of residue  would result in an accumula-




tion of 4 pounds per square meter per year and the  lime mud would add




another two.  If the annual accumulation  of 18,000  tons of Kelly




residue and 8,600 tons of lime mud were completely  dissolved and/or




suspended at any one time over this same  area, to a depth of one




meter, the concentration would be about 3000 mg/1.  (Assuming a free




cyanide ratio of 20 micrograms per gram,  the concentration of HCN




would be very near the maximum recommended allowable.)  Considering




the fact that distribution over another meter would reduce the con-




centration to one half this value, plus the extreme possibility




against its occurrence in the first place, it seems unlikely that a




dangerous situation regarding the solids would exist.  In considering




the HCN danger,  it should be pointed out  that the concentration would




be reduced in time by bacterial decomposition.




             According to Fair and Geyer  (1954), deposited solids may be




lifted from the bottom and transported if theoverlying water has a




velocity above a critical value dependent on grain size, frictional




resistance,  and cbheSiveness of the particles.  With some assumptions




a value of 7,3 cm/sec was computed for an estimated mean grain size




of 0,02 mm»   The fact that the bottom is much lower than the edge of




the continental shelf (80-90 fathoms) in this area (Carlson, 1968)

-------
                                                                       13






suggests that even if currents of this magnitude occur, scoured




bottom material would be subject to considerable additional impediments




to transport toward the beach (Sverdrup, Johnson and Fleming,  1942)»




             Merely as a point of reference, it is noted that  New York




city disposes of 175,000 tons of sewage sludge annually, by barging to




a disposal area 13 miles east of New York Harbor, where the water




depth is 30 meters.






IV.  Summary and Recommendations




     The analysis at hand indicates that acute pollution problems are




not likely to occur at the dumping site, but that a short-term prob-




lem may arise due to the high HCN concentration associated with an




accidental spill of a barge in the Columbia River.  Similar disposal




situations have not been sufficiently studied to allow precise deter-




mination of the fate of the solids or prediction of long-term  pollu-




tional effects.  In this light the following recommendations are




offered:




     1)  Based upon computed settling rates and apparent effect of hori-




zontal dispersion by currents, it appears that proposed dump site two




would be the most favorable.  It is in water approximately 900 fathoms




(1647 meters) deep and near the mouth of Willapa Canyon, which will




cause deep settling material to be funneled further seaward.  Also, it




is further from the continental shelf than either site one or three.




If possible, this recommendation should be reviewed after a hydrographic




study to ascertain bottom currents in the area.

-------
                                                                     14






     2)  The CN" content of each barge load should be determined before




departure,




     3)  Each barge voyage should be forecast and accidental groundings




or spills reported to an appropriate monitor.




     4)  Further study of the sedimentation mechanics of this type of




disposal method should be supported with special emphasis on prototype




studies,




     5)  Additional evidence should be sought on the long-term biological




effects of low HCN concentrations in sea water.




     6)  Any permit to dump should be subject to review on the basis of




additional evidence provided by the studies recommended.

-------
                                 References
Budinger, T. F., L. K. Coachman, and C. A. Barnes.  1964.  Columbia
     River Effluent in the Northeast Pacific Ocean, 1961,  1962:  Selected
     Aspects of Physical Oceanography.  Technical Report No. 99,
     Department of Oceanography, University of Washington, Seattle,  78 p.

Carlson, P. R.  1968.  Marine Geology of Astoria Submarine Canyon.
     Ph.D. thesis.  Oregon State University, Corvallis.  259 p.

Fair, G. M., and J. C. Geyer.  1954.  Water Supply and Waste Water
     Disposal.  Wiley, New York.  973 p.

Morton, B. R., Sir Geoffrey Taylor, and J. S. Turner.  1956.  Turbulent
     Gravitational Convection from Maintained and Instantaneous Sources.
     Proc. Royal Soc. London. Ser. A., 234: pp. 1-23.

McKee, J. E. and H. W. Wolfe.  1963.  Water Quality Criteria.  State
     Water Quality Control Board, State of California, Sacramento.
     548 p.

Stevenson, M. R.  1966.  Subsurface currents off the Oregon Coast.
     Ph.D. thesis.  Oregon State University, Corvallis.  140 p.

Sverdrup, H. U., M. W. Johnson, and R. H. Fleming.  1942.  The Oceans.
     Prentice Hall, Englewood Cliffs, N. J. 1087 p.

-------