ENVIRONMENTAL HEALTH
SERIES
Water Supply
and Pollution Control
U. S, DEPARTMENT OF HEALTH,
EDUCATION, AND WELFARE
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DUCK-PROCESSING WASTE
Grover L. Morris
Water Supply and Waste Treatment Unit
Technical Advisory and Investigations Section
Technical Services Branch
Robert A. Taft Sanitary Engineering Center
U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFARE
Public Health Service
Division of Water Supply and Pollution Control
Cincinnati, Ohio
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The ENVIRONMENT AL HEALTH SERIES of reports was estab-
lished to report the results of scientific and engineering studies of
man's environment: The community, whether urban, suburban, or
rural, where he lives, works, and plays; the air, water, and earth he
uses and reuses; and the wastes he produces and must dispose of in a
way that preserves these natural resources. This SERIES of reports
provides for professional users a central source of information on the
intramural research activities of Divisions and Centers within the
Public Health Service, and on their cooperative activities with State
and local agencies, research institutions, and industrial organizations .
The general subject area of each report is indicated by the two letters
that appear in the publication number; the indicators are
WP - Water Supply
and Pollution Control
AP - Air Pollution
AH - Arctic Health
EE - Environmental Engineering
FP - Food Protection
OH - Occupational Health
RH - Rad iological Health
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Reports in the SERIES will be distributed to requesters, as
supplies permit. Requests should be directed to the Division identi-
fied on the title page or to the Publications Office, Robert A. Taft
Sanitary Engineering Center, Cincinnati, Ohio 45226.
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CONTENTS
Page
ABSTRACT v
INTRODUCTION 1
SURVEY PROCEDURES 1
DESCRIPTION OF PLANTS 2
PRESENTATION OF DATA 3
DISCUSSION 8
ACKNOWLEDGMENT H
REFERENCES 13
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ABSTRACT
Two duck-processing plants located on Long Island were studied
to obtain waste load and water use data for comparison with chicken
processing data.
Weighted averages for both plants studied indicate water use of
23. 6 gallons and waste loads of 0. 0419 pound BOD and 0. 0289 pound of
suspended solids per duck processed. Similar values for chicken pro-
cessing are 8 gallons of water, 0. 025 pound of BOD, and 0. 013 pound
of suspended solids per bird.
Comparisons between duck and chicken processing on the basis
of 1, 000 pounds of live birds indicate water usage is 3, 600 gallons for
ducks and 2, 30Q gallons for chickens; BOD values are 6.4 pounds for
ducks and 7. 18 pounds for chickens; and suspended solids values are
28, 9 pounds for ducks and 13 pounds for chickens. Waste water coli-
form values were 56,800 per 100 milliliter in plant A and 49,200 per
100 milliliter in plant B.
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DUCK-PROCESSING WASTE
INTRODUCTION
The center of duck production activity has historically been
located on Long Island where the sandy shores, salt-water coves, and
estuaries together with a supply of uncontaminated ground water have,
in the past, been abundantly available. Long Island produces 60 to
70 percent of the total ducks processed for market under Federal
inspection. *
In recent years and particularly since World War II, the influx
of people to Long Island has rapidly increased. The development of
new areas and the expansion of established areas for houses, busi-
nesses, industry, recreational and resort activities, and governmental
installations have resulted in increased pressure for water pollution
control and in competition for available fresh water. The duck indus-
try is also competing for unpolluted water supply and recognizes the
increasing importance of water conservation to delay the possible
depletion of existing supplies or contamination of these supplies by
intrusion of salt water or other materials.
Much has been written about the pollution control problems of
duck farms, ^ but little information is available pertaining to
water use and waste loads associated with duck-processing plants.
Recognizing this need for information, the Agricultural Market-
ing Service, Poultry Division, U.S. Department of Agriculture, and
the Public Health Service, Water Supply and Pollution Control Division,
have cooperated in field studies to secure data from two Long Island
processing plants for evaluation. These studies form the basis for
this report.
Objectives of the study were (1) to measure and evaluate duck-
processing plant waste loads and (2) to observe plant operations for
possible reduction in total water use by redistribution or by reuse of
certain waters presently discharged to waste after one use, or by a
combination of redistribution and reuse.
SURVEY PROCEDURES
Two processing plants, designated A and B, were studied.
Weirs and water-level recorders were installed on plant-waste
discharge lines for measurement of flow on the days when chemical
and bacteriological samples were collected.
The chemical samples were collected at 30-minute intervals
during the processing and cleanup periods in the plant. Incremental
samples were composited to provide one daily sample from each waste
source. Bacteriological samples were collected twice each day, at
midmorning and midafternoon.
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Composite samples were examined in the laboratory for bio-
chemical oxygen demand (BOD), suspended solids (SS), volatile sus-
pended solids (VSS), grease, hydrogen ion concentration (pH), ammonia
nitrogen, organic nitrogen, total phosphate, and total coliform by the
membrane filter technique (MF). The analyses were performed in
accordance with Standard Methods for the Examination of Water and
Waste Water, 11th edition, I960.
Analytical work was performed by PHS personnel at the Duck
Research Laboratory, Eastport, L.I. Supporting field personnel
were furnished by both the Agricultural Marketing Service and Public
Health Service.
DESCRIPTION OF PLANTS
Plant A
Plant A is a two-line plant designed for processing 1, 200 ducks
per line per hour.
Ducks are hauled from the farms each morning in semitrailers
equipped with two decks and compartmented by use of adjustable and
removable partitions located on each deck. At the plant, ducks are
unloaded into holding pens, according to ownership, from which they
are herded into a runway and hung on traveling shackles. They then
proceed through the plant operations in the following order: kill and
bleed, electric eye count, scald, defeather, first hot-wax dip, chill,
remove wax, second hot-wax dip, chill, remove wax, pin, eviscerate,
chill, grade, wrap, weigh, package, freeze, and store. All product
processing at this plant is Federally inspected.
Liquid blood from the bleed room floor flows into a pit from
where it is pumped into a Dempster-Dumpster container outside the
building. This blood is hauled to the local dump for disposal. Con-
gealed blood remaining on the floor at the end of the day is flushed
into waste line No. 1.
Feathers are recovered from the dressing area flow-away
system by rotary screens and returned to the duck raiser, feet are
packaged for shipment to Hong Kong. Heads, trimmings, and viscera
are removed from the evisceration flow-away system by rotary
screens, passed through a grinder, and then packaged, frozen, and
shipped to mink farms.
Process liquid wastes are discharged to a settling pond, thence
to a second pond. The effluent from pond No, 2 is discharged to an
arm of Moriches Bay. Cooling water from refrigeration equipment is
discharged to pond No. 2. Sanitary wastes are discharged to a septic
tank and absorption field.
Plant B
Plant B is a single-line operation with a variable production
capacity depending upon the number of employees, the operating time,
and the section of plant utilized. There are two separate plants on
this farm both under Federal supervision: a New York Dressed Kosher
operation and a dressing and eviscerating unit. The dressing and
eviscerating unit was used for this study.
2
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This privately owned plant processes ducks raised by the
owners. The ducks are trucked to the plant, unloaded into holding
pens, and then herded into a runway and hung on traveling shackles.
The processing procedure is as follows: kill and bleed, scald, de-
feather, first hot-wax dip, chill, remove wax, second hot-wax dip,
chill, remove wax, pin, eviscerate, cleanup, chill, grade, wrap,
weigh, package, freeze, store, and ship.
All liquid wastes, except blood, are collected in a single outfall
line and discharged to ponds. Feathers, feet, viscera, blood, and
other parts are handled similarly to the same materials in plant A.
PRESENTATION OF DATA
Plant A
The waste flows from plant A are separated into four categories,
since the piping arrangement in the plant provides for four separate
discharge lines.
Waste line 1 collects wastes from the dressing operation, in-
cluding holding, killing, scalding, defeathering, waxing, pinning,
grading, packaging, refrigerating, and storing. Waste line 1 dis-
charges into pond No. 1.
Waste line 2 collects wastes from the evisceration operation,
including the head, neck, feet, viscera, and wastes from cleanup and
the chill tanks. This waste line discharges to pond No. 1 below the
water surface.
Waste ±ine 3 collects the sanitary wastes from the plant and
office toilets, lavatories, drinking fountains, showers, etc. Waste
line 3 discharges to a septic tank and absorption field on the plant
grounds. The flow and strength of this waste were not measured.
Waste line 4 collects cooling water from the refrigeration com-
pressors and condensors. Waste line 4 discharges without further
use to pond No. 2. The volume of this waste water was not measured,
but was estimated.
The total water supply from the two plant wells was metered.
Data on water supply and waste discharge volumes are presented in
Table 1.
Line 2 discharges below the surface of pond No. 1, which makes
a direct measurement of flow difficult. Consequently, the outflow
from pond No. 1 was measured and the flow from line 2 was computed
by difference with an allowance made for pond seepage. Samples
from line 2 were withdrawn from the evisceration waste rotary screen
pit inside the plant building. Samples from line 1 were collected at
the point of discharge to pond No. 1.
In manipulation of the raw data to compute pounds of waste and
unit values of production, only the waste volume from waste line 1
(dressing operation) and waste line 2 (evisceration operation) were
used. The sanitary and cooling water wastes were disregarded since
they were not mixed with the other plant wastes and were not sampled.
WASTE
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Table 1. PLANT A, WATER SUPPLY AND WASTE FLOW
Date,
Water
Waste
Waste
Wa ste
Waste
March
supply,
line 1,
line 2,
line 3, a
line 4, a
1964
metered,
measured,
computed,
e stimated,
estimated,
gP<*
gpd
gpd
gPd
gPd
16
491. 700
162,700
236,300
42,300
50, 400
18
402,900
124,600
180,700
47,200
50, 400
19
403,500
129, 200
176, 900
47,000
50,400
23
406, 100
144,000
176, 000
35, 700
50,400
Total
1,704,200
560,500
769,900
172,200
201,600
aNot included in calculations for waste strength and unit values.
The BOD and chemical analyses of composite samples from
waste lines 1 and 2 are shown in Table 2. Of interest are the lower
values of pH, BOD, SS, and phosphate concentrations in the waste
from evisceration as compared with those from the waste from dress-
ing. The pH value is significantly raised in the dressing waste because
of the alkaline blood present and the smaller quantity of water used.
The well-water supply has a pH of 6. 2 from well No. 1 and 6. 4 from
well No. 2,
The average BOD concentration for the 4 days is less in the
evisceration waste water owing to She greater volume of water used in
the evisceration process. The total pounds of BOD in each waste are,
however, comparable since waste line 1 contained 5 5 percent, and
waste line 2, 45 percent of the total. Total pounds of SS were similarly
distributed, with 57 percent in waste line 1 and 43 percent in waste
line 2; the pounds of total phosphate were distributed 67 percent and
33 percent in waste lines 1 and 2, respectively.
The amount of grease was considerably greater in the eviscera-
tion waste, as would be expected. Total coiform (MF) was signifi-
cantly less in the evisceration waste than in the dressing waste. The
weighted average of total coliform for all processing wastes was
56, 800 per 100 milliliters, as indicated in Table 3.
Unit value relationships of waste discharged, versus product pro-
duced, as presented in Table 3, are computed from measured values
of waste flow, concentration of pollutants present, and the number of
ducks processed.
Average volume of waste per duck processed at Plant A was 24. 3
gallons. This is three times the average of 8 gallons per chicken as
reported by Porges and Struzeski. ® Comparison of flow on the basis
of the average live weight of ducks and chickens indicates 3. 6 gallons
per pound of duck and 2. 3 gallons per pound of chicken. The duck
waste flow on this equivalent weight basis is only one-and-one-half
times greater than the chicken waste flow.
4
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3
>
w
frj
Table 2. PLANT A, LABORATORY AND PHYSICAL DATA
Date
3-16-64
W
1
H-
00
t
0-
hU
3-19-64
3-23-64
Waste line
1
2
1
2
1
2
1
2
Ducks processed, No.
16, 225
12, 370
12, 026
14, 070
Evise wt, total lb
81. 419
52,494
56, 655
64,254
Waste water flow, gpd
162,700
236, 300
124,600
180,700
129,200
176, 900
144, 000
176, 600
PH
7. 0
6, 6
7. 1
6. 5
7. 4
6. 4
6. 7
6.7
BOD, mg/liter
278
160
276
136
241
175
317
189
SS, mg/liter
217
97
232
130
177
121
203
108
VSS, mg/liter
206
96
188
113
161
115
191
107
Grease, mg/liter
31
78
105
132
28
109
51
178
NH4-N, mg/liter
0. 65
0.05
1.27
0. 07
0. 51
O
O
0.78
0. 05
Org-N, mg/liter
43
14
41
13
42
12
44
13
Total PO4, mg/liter
90
35
136
32
191
49
93
31
Coliform (MF), No./100 ml
140,000
7, 600
48, 000
7, 400
56. 000
7, 400
150,000
14, 000
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Table 3. PLANT A, UNIT VALUES: WASTE VS PRODUCT
Date
3-16-64
3-18-64
3-19-64
3-23-64
Weighted
Waste line
1
2
Total
1
2
Total
1
2
Total
1
2
T otal
average
Ducks processed, No.
16, 225
12,370
12,026
14, 070
Daily waste flow, gala
162,700
236, 300
124,600
180,700
129,200
176, 900
144,000
176, 600
Gal waste/duck processed
10. 0
14. 6
24. 6
10. 0
14. 6
24.6
10. 7
14. 7
25. 4
10.2
12. 6
22. 8
24. 3
Live wt, lb'5
116,500
75, 000
81,000
91,800
Avg live wt, lb
7. 17
6.06
6.73
6.53
6. 66
Gal/1, 000 lb live wt
1. 395
2, 035
3,430
1, 660
2,400
4, 060
1, 595
2, 185
3,780
1, 570
1, 920
3,490
3, 650
Evis wt, lbc
81,419
52, 494
56, 655
64,254
Avg evis wt, lb
5.02
4. 24
4. 17
4, 57
4. 66
Gal/ 1, 000 lb evis wt
2, 000
2, 910
4, 910
2, 375
3,440
5, 815
2,280
3. 120
5, 400
2, 240
2, 750
4, 900
5, 220
BOD, lb
377
316
693
287
205
492
260
258
518
382
278
660
BOD, lb/ 1,000 live duck
42. 7
39. 8
43. 0
46. 9
43.2
BOD, lb/1, 000 lb live wt
5. 94
6.56
6. 39
7. 18
6. 49
BOD, lb/1, 000 lb evis wt
8. 52
9. 37
9. 15
10.28
9. 27
Live ducks, No. /PE^
3.91
4.53
3.89
3. 57
3.87
SS. lb
294
192
486
241
196
437
191
179
370
245
159
404
SS, lb/ 1, 000 live duck
30. 0
35.4
30.7
28.7
31.0
SS, lb/1,000 lb live wt
4. 17
5. 83
4.57
4.41
4. 66
SS, lb/1,000 lb evis wt
5.97
8. 32
6.53
6.29
6. 65
Coliform, No./100 ml
56,800
d
a
o
w
t)
!«
O
o
PJ
to
CO
§
O
^Excludes coaling water for refrigeration and water for employee sanitation.
''Live weight computed; multiply eviscerated weight by factor 1.43.
cEviscerated weight is scale weight.
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In the waste flow-away systems of plant A, the BOD was 43 pounds
per 1,000 ducks. Similarly, for chicken waste the BOD was 25 pounds
per 1,000 chickens. ^ When these values are compared on the basis of
average live weight, we obtain values of 6. 5 pounds BOD per 1, 000
pounds duck and 7. 1 pounds BOD per 1, 000 pounds chicken. The SS
values are 4. 7 pounds per 1, 000 pounds duck and 3. 7 pounds per 1, 000
pounds chicken.
Plant B
All the flow-away wastes except blood from processing plant B
are screened, collected into a single sewer, and then discharged into
open ponds excavated in sandy soil. These ponds have no surface
discharge since the waste seeps into the underground sands. One pond
is used until the seepage rate decreases to less than the total daily
addition of waste, whereupon another pond is used and the first one is
allowed to dry. The accumulated solids are removed from the walls
and bottom of the dry pond and buried at another location. Exposure
of the fresh sand prepares the dry pond for additional service.
The water supply to plant B is furnished from wells, but these
were not equipped with meters for measuring the quantity used. The
waste flow was diverted over a V-notch weir with continuous measure-
ment of the head by a water-level recorder. Waste flow values are
not given at the request of the plant owner.
Laboratory data are shown in Table 4. The BOD concentration is
within the range of ordinary domestic sewage whereas SS, ammonia,
and coliform are less and the grease and total phosphate concentrations
are larger.
Table 4. PLANT B, LABORATORY AND PHYSICAL DATA
Date 3-19-64 3-20-64 3-25-64
Evis wt, total lb
17,506
16,207
12,114
pH
7.2
7. 0
7. 2
BOD, mg/liter
172
209
261
SS, mg/liter
130
94
105
VSS, mg/liter
123
79
99
Grease, mg/liter
111
67
98
NH4-N, mg/liter
0. 36
0. 84
0. 35
Org-N, mg/liter
16. 8
28. 1
31.0
Total PO4, mg/liter
79
57
83
Coliform, No./100 ml
16, 000
78,000
51,000
Unit values for several relationships between production and
waste loads are shown in Table 5. Waste flow varied from 17.7 to
23.4 gallons per duck processed and from 4, 170 to 5, 380 gallons per
1, 000 pounds ready-to-cook duck.
WASTE
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Table 5. PLANT B, UNIT VALUES: WASTE VS PRODUCTS
Weighted
Date 3
-19-64
3-20-64
3-25-64
T otal
ave rage
Gal waste/duck processed
19. 4
23. 4
17. 7
20. 1
Avg live wt, lb
6. 67
6. 70
4. 69
6. 00
Gal/1, 000 lb live wt
2, 910
3, 500
3, 760
3, 350
Avg evis wt, lb
4. 67
4. 68
3. 28
4. 21
Gal/1,000 lb evis wt
4, 170
5, 010
5, 380
4, 780
BOD, lb
105
141
142
388
BOD, lb/1,000 live duck
28
41
38
35. 6
BOD, lb/ 1, 000 lb live wt
4. 19
6. 07
8. 21
5. 92
BOD, lb/1, 000 lb evis wt
5. 98
8. 70
11. 70
8. 46
Live ducks, No. /PEa
5. 96
4. 07
4. 39
4. 64
SS, lb
79
64
57
200
SS, lb/1,000 live duck
21. 1
18. 5
15.5
18. 3
SS, lb/1, 000 lb live wt
3. 16
2. 76
3. 29
3. 05
SS, lb/ 1,000 lb evis wt
4. 51
3. 95
4. 71
4. 37
Coliform, No./100 ml
49,200
aPopulation Equivalent (PE) is based on 0. 1 67 pound of BOD per person.
The BOD and SS varied from 28 to 41 pounds and 15 to 21 pounds,
respectively, per 1, 000 live ducks. Total coliform varied in concen-
tration from 16, 000 to 78, 000 per 100 milliliters, with a weighted
average of 49, 200 per 100 milliliters for the 3 days when samples
were collected.
DISCUSSION
Study of two duck-processing plants located on Long Island pro-
vides data pertaining to water use, waste loads, and general operation.
The finished product is a high-quality duck of considerable delicacy.
The relatively short processing time of approximately 1-1/4
hours between kill and quick freeze operations, the abundant use of
water for cleaning and chilling, coupled with careful inspection and
grading, contribute to maintenance of a very high-quality product.
Relatively low coliform counts in the flow-away water from the
evisceration process indicate careful operation in the removal of
viscera, with infrequent rupture of the intestines and possible con-
tamination of the carcass. Fortunately at plant A it was possible to
determine coliform concentrations separately for evisceration and
dressing operations. Measured values in the evisceration waste
varied from 7, 400 to 14, 000 coliform per 100 milliliters with a
weighted average of 9, 000 per 100 milliliters. Total coliform con-
centrations found in composite duck-processing waste varied from
16, 000 to 150, 000 per 100 milliliters with a weighted average (both
plants) of 55,700 per 100 milliliters.
Water usage in duck-processing plants seems rather high when
one compares the waste volume from duck processing with the waste
volume in chicken processing. In Table 6 the overall average waste
volume for both duck plants was 23. 6 gallons per duck as compared
8
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with 8 gallons per chicken processed. When water uses based on
waste volumes are compared on the basis of live weight, we have
i, 600 gallons per 1, 000 pounds live duck and 2, 300 gallons per 1, 000
pounds live chicken or 57 percent greater usage for ducks. The evis-
cerated weight figures are 5, 150 gallons of waste per 1, 000 pounds
duck and 2, 890 gallons per 1, 000 pounds chicken or 78 percent greater
water usage in duck processing.
Table 6. SUMMARY DATA: DUCK AND CHICKEN PROCESSING
Duck plant
Duck plant
T otal-avga
A
B
both
Chicken
duck plants
processing
Waste flow, total gal
1, 330, 400
8,000b
Birds processed, total No,
54,691
1, 000
Gal waste/bird processed
24. 3
20. 1
23. 6
8
Live wt, total, lb
364,300
3, 480
Avg live wt, lb
6. 66
6. 00
6. 55
3. 48b
Gal/ 1, 000 lb live wt
3, 650
3, 350
3, 600
2, 300
Evis wt, total lb
254,822
2,765c
Avg evis wt, lb
4. 66
4. 21
4. 58
2.76
Gal/ 1, 000 lb evis wt
5, 220
4, 780
5, 150
2, 890
BOD, mg/liter
213
212
213
374
BOD, lb, total
2, 363
388
2, 751
25
BOD, lb/ 1, 000 live birds
43. 2
35, 6
41. 9
25b
BOD, lb/ 1, 000 lb live birds
6. 49
5.92
6. 40
7. 18
BOD, lb/1, 000 lb evis bird
9. 27
8. 46
9. 15
9. 04
Live birds, No./PE^
3. 87
4. 64
3. 99
6. 68
SS, mg/liter
155
110
147
195
SS, lb, total
1, 697
200
1, 897
13
SS, lb/1,000 live birds
31.0
18. 3
28. 9
13b
SS, lb/1, 000 lb live birds
4. 66
3. 05
4. 41
3. 73
SS, lb/ 1,000 lb evis bird
6. 65
4. 37
6. 31
4. 70
Total coliform, No. / 1 00 ml
56, 800
49,200
55,700
^Weighted averages.
bRefe rence No. 6.
cEviscerated weight of chickens, 74 percent of live weight,
•^Population Equivalent (PE) is based on 0. 167 pound of BOD per person.
Reduction in total water used in duck processing could probably
be achieved without lowering product quality by adoption of some of the
conservation concepts listed below:
1. The clean water from refrigeration compressors and con-
densors could be used for boiler make-up water, holding
pen cleaning, scald vat, dressing room cleanup, and
feather flow-away and evisceration flow-away systems.
2. The chill water used following evisceration could be reused
for hardening wax in pinning operations, for scald tank,
flow-away flumes in dressing and evisceration operations,
and floor washing in holding pens, bleed room, and picking
areas. Fine screening of the chill water may be necessary
for some of these reuses.
WASTE
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3. The entire water system should be designed and operated
to provide the proper quantity of water at the proper
pressure to perform the task required at the various stations
on the processing line. This concept could be realized by
evaluation of the number, size, and shape of nozzles needed
and by control of nozzle pressure by use of pressure-reduc-
ing valves. Since the quantity of water discharged through a
given orifice is related to the pressure, an incremental
saving in water per outlet would add up to a large volume
when the great number of nozzles used in the plant is con-
sidered.
Table 6 provides other comparisons between wastes from duck
processing and chicken processing. The BOD concentrations vary
widely, but when these are reduced to pounds of BOD per unit of pro-
duction the difference is less significant. For example, the pounds of
BOD per 1, 000 pounds of eviscerated bird is 9. 15 pounds for ducks
and 9-04 pounds for chickens. The pounds of BOD per 1, 000 pounds
of live bird were 6. 40 pounds BOD for ducks and 7.18 pounds for
chickens.
From these data it is possible to establish comparable unit
waste values between the processing of ducks and other poultry by
making such comparisons on the basis of unit weight.
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ACKNOWLEDGMENT
The author wishes to acknowledge the splendid cooperation in
this study extended to the Public Health Service by the U.S. Depart-
ment of Agriculture and the Long Island Duck industry.
Special recognition is made of the support, cooperation, and
advice by Dr. J. R. Harney and Dr. A. G. Wilder, U.S. Department
of Agriculture; Dr. Louis Leibovitz, Long Island Duck Research
Laboratory; Mr. Fred Buzen, Long Island Duck Farmers Cooperative
Inc.; Mr. Ralph Sweeney, New York State Health Department; Mr.
Herbert W, Davids, Suffolk County Health Department; Mr. Ralph
Porges, Dr. Graham Walton, Mr. Carl Shadix, and Mr. Robert
McCullough, Public Health Service, Robert A. Taft Sanitary En-
gineering Center, Cincinnati, Ohio.
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REFERENCES
1. Statistical Reporting Service, Crop Reporting Board, U.S. De-
partment of Agriculture.
2. Moriches Bay Drainage Basin, New York State WPC Board,
Suffolk County Survey Series Report No. 1. January 1951.
3. Gates, C.D. Treatment of Long Island duck farm wastes,
JWPCF, 35 (12): 1569. 1963.
4. Alternating lagoon system removes settleable solids from duck
wastes. Clean Waters {New York State WPC Board). 2:3.
Nov. 1953.
5. Porges, R. , and E.J, Struzeski. Wastes from the poultry pro-
cessing industry. Tech. Rept. W62-3. SEC. 1963. 40 pp.
GPO 821—607—2
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