United States
                    Environmental Protection
                    Agency
Water Engineering
Research Laboratory
Cincinnati OH 45268
                    Research and Development
EPA/600/S2-87/034  Aug. 1987
SEPA          Project  Summary
                    Nitrate  Removal from
                    Contaminated Water  Supplies:
                    Volume  II
                    Gerald A. Outer
                     Nitrate removal from contaminated
                    water using the ion exchange process
                    was evaluated at a 1 million gal a day
                    (mgd) plant at McFarland, CA. The
                    plant supplied most of the community's
                    water needs during  1985 and 1986.
                    This document summarizes the second
                    of a two-volume report and focuses on
                    analysis of operation and maintenance
                    (O&M) costs and plant performance
                    from December 1, 1984, to January
                    1,  1987.  Volume I focused on the
                    design and the first 6 months of its
                    automatic operation.
                     Accurate cost and operational data
                    were  obtained to determine actual
                    treatment costs. When the plant started
                    operation, nitrate levels in the raw
                    water were 15.8 mg  NO3-N/L. As
                    operation  continued over the  3 yr,
                    nitrate levels fell, as well as the amount
                    of  other anions.  A correlation was
                    observed between long-term monthly
                    pumping rate and nitrate level in the
                    raw water.
                     It is believed that this data comprises
                    the most comprehensive cost and
                    performance information ever accum-
                    ulated  on an ion exchange nitrate
                    removal system for the production of
                    safe drinking water from contaminated
                    groundwater. Extensive data on dispo-
                    sal  of waste from the plant is also
                    included.
                     Actual O&M costs of 8.50/1000 gal
                    (based on design  capacity of 1 mgd)
                    were 36% lower than cost estimates
                    published previously. These lower
                    costs are attributable to a number of
                    factors that include: drop in nitrate and
                    sulfate levels in the raw water, auto-
                    matic operation, automatic hourly
nitrate  measurement,  automatic
recording of plant operating  condi-
tions, daily remote telecomputer
communication, operation based  on
partial regeneration, and  a column
design which provided nearly 100%
column efficiency.
  Wastewater composition and pro-
duction were studied to characterize
the type of wastewater produced. The
wastewater  entered  the local  sewer
collection system and eventually was
disposed  of as irrigation  water for
cotton production.  Soil  and  water
conditions were monitored over a 4 yr
period at the disposal area. Only slight
effects were noted in soil characteris-
tics and  groundwater composition
from nearby wells. Approximately 125
tons of waste solids are disposed of per
year at the site and a serious impact
is expected  to occur on a long-term;
basis. This is of special concern
because of a second plant to be oper-
ational in McFarland in 1987.
  This Project Summary  was  devel-
oped by  ERA'S Water Engineering
Research Laboratory. Cincinnati, OH.
to announce  key  findings of the
research  project that is fully docu-
mented in a separate report of the same-
title (see Project Report ordering
information at back).

Introduction
  The McFarland,  CA, nitrate removal.
demonstration project  involved the
design, construction, and operation of a
nitrate removal plant at Well No. 2 owned
and operated by the McFarland Mutual
Water Company. This volume covers the
nitrate plant operation from December 1,

-------
1984, to January  1, 1987. Volume 1
covered the design, startup, and  initial
performance of the plant (Reference 1).
The period of operation spanned by these
two  volumes is  the 38 months from
November of 1983 to January of  1987.
During  most of this time the  plant
functioned as the community's primary
water supply.
  The  plant  continues to serve the
community as a major source of drinking
water that meets the nitrate maximum
contaminant level (MCL). A second plant
is presently under  construction at Well
No. 4 and is anticipated to be operational
in the summer of 1987. The full report
includes cost information on the second
McFarland nitrate plant. A  third project
is being planned to treat other wells with
the existing plants.
  Experimental  work was also  done
under this program on  nitrate  selective
resins, wastewater recycling, automatic
nitrate monitoring, and telecomputer
monitoring.
  The  grant  period  covered  by both
volumes of this report is from September
1981 to April 1987. The work effort is
a followup to work done under a previous
grant reported in  Reference 2.
  Much information on plant design and
related research  has been published. In
addition to the above two references,
previously published papers contain
information developed under both grants
(References 3, 4, 5,  6, and 7). A U.S.
Patent was issued October 1984 on the
use of a nitrate selective resin in  water
treatment (Reference 8).

Plant Operation
  The data period covered in this report
begins December 1, 1984,  immediately
after the period covered in Volume I and
continues to January 1, 1987. Data for
the months preceding December  1984
are also listed in some  of the  following
data tables for comparison. Data for the
period up to January  1,  1986,  are given
detailed analyses,  and  are believed to
adequately represent  the treatment
costs. Data for 1986 are listed in sum-
mary form and are important because of
the use of the 5-ft resin bed instead of
the 3-ft bed used earlier.
  Daily records of flows, flow rates, and
nitrate levels were maintained through-
out the above period of operation. Data
were obtained  by manual  readings,
record keeping,  and automatic data
logging by the microprocessor.  The plant
was operated entirely in the automatic
mode. The most  time consuming tasks
of the operator were the data logging and
record keeping of operation.
  From the da ily reports described above,
monthly reports were  compiled in con-
formance with the requirements of the
California State Division of Health. Table
1 is an example of data for 1 month of
operation.
  In the table, column 2 gives the daily
quantity of water  pumped to  the distri-
bution system. This water was  a  blend
of the treated water and  bypassed
quantities  shown  in columns 3 and  4.
Column 5 lists the amounts of saturated
brine used daily for regeneration. The
next two columns list the average nitrate
levels in the blended water delivered to
the distribution system. The  remainder
of the columns lists  the type of waste-
water produced and the daily totals. The
last line of each of  the columns gives
the total water quantity  and  monthly
average nitrate level.
  Table 2  lists the anion  compositions
of raw water, treated water, and  blended
water. These data  are taken  from
monthly analyses  performed  by a State
certified laboratory.
  It can be  noted that the raw  water
quality gradually  improved and nitrate
values dropped below  the MCL  in June
1985. Decreases in the other interfering
anions also occurred over this period of
operation.  Continuation of operation was
required by  the  State  of California  to
maintain nitrate below 7.9 mg  NO3-N/
L.
  Table  3 shows brine  dosages and
service batch with monthly summaries
of other data. Salt dose was maintained
at 5.61 Ib/ft3 of resin [1.5 bed volume
(BV)  of 6% NaCI solution] although
actually measured amounts varied, but
averaged 5.42. The  percent  of treated
water  in  the distributed blend was
manually adjusted from time to time to
reflect  actual  or  anticipated seasonal
changes in untreated water composition
and to  maintain the nitrate level  below
7.9 mg N03-N/L as required by the State
operating permit.
  Primary  performance data  are evalu-
ated  by comparing  the actual perfor-
mance data  with estimates from ion
exchange theory. The major parameters
related to operating costs here are nitrate
leakages and the consumption of regen-
erant salt per amount of nitrate removed
from raw water.
  Five criteria can be used to  evaluate
plant performance.  These are: salt
dosage requirements,  brine use factors,
nitrate leakages, column efficiency, and
effluent histories. These quantities were
measured and  compared  to  projectec
values  or estimates  from theoretica
considerations to determine if the plam
performance was optimum, or if not, tc
determine the cause of inefficiency.
  The  secondary  plant  performance
factors for the  1985 year  are given in
Table 4. The overall percentages of brine
and produced wastewater are comparec
in the  last two lines of the table.  The
wastewater disposed to the sewer  sys-
tem  was only  2.53% of the water
pumped, giving a remarkably high water
recovery of 97.47%. Improved secondary
performance was achieved in 1986.
  Other operating data of interest  are
given  in  Table  5,  which shows  the
average  monthly brine dose for  the
regeneration of each vessel. The number
of regenerations varied from about  one
to three per day. The amount of sodium
chloride  used  for  regeneration variec
from about 11,000 Ib to 53,000  Ib per
month. The amount delivered per truck
load to the site was 25,000 Ib. The peak
month  required about two deliveries per
month  and the low month  required  one
delivery about every 2 months. The lasi
column gives the service volume settings
per  month.   These  settings  were
increased during the last  2 months tc
accommodate the improvement in watei
quality and the anticipated changes foi
testing the 5-ft resin bed operation.

Capital and O&M Costs

Capital Costs
  The capital costs for the constructior
of the nitrate plant at Well No. 2 are giver
in Table 6. Table 6 shows costs for  twc
different sizes of vessels and resin bed;
to accommodate 3-ft-deep beds and 5
ft beds. The first McFarland plant  was
constructed with taller vessels to accom
modate  both  beds.  The cost   was
$355,638(1983).

O&M Costs
   In Volume 1 (Reference 1) and previous
publications (References 2, 5, and 6)
O&M costs were based on a mix of actua
and  estimated  cost  data. These cost!
have been revised  using  figures frorr
McFarland Mutual Water Company  file;
for the years 1985 and 1986. The  cos
data are listed in Table 7.

Total Costs
  Two methods that  are very useful fo
analyzing costs are presented  here.  Th<

-------
two methods are total costs based on
design flow and total costs based on
actual  plant flow. The full  report dis-
cusses a number of other ways to analyze
costs including costs that are specific to
the McFarland, CA, community.
  Based on design flow of 1  mgd. Table
8 shows O&M costs  of 8.50/1000 gal
(1984-1985) and capital costs of 9.9C/
1000  gal (1983). Capital  costs  were
amortized over 20 yr at 8% interest.
Therefore, total  cost including capital
plus O&M  was  18.40/1000 gal. Con-
struction cost  increased  approximately
1%/yr over the 1983-1986  period and
therefore total cost should be adjusted
upward slightly to reflect this.
  Based  on actual flow,  the plant pro-
cessed 343 million gal of water over the
1985-1986 period for  an average of 0.47
mgd.  Fixed O&M costs  (Table 8) will
increase from 4.10/1000 gal to 8.70/
1000 gal and total  O&M cost will be
13.10/1000 gal.  Capital  cost  will
increase from 9.90/1000 gal to 21.10/
1000 gal. Therefore, total costs, when
pumping at  an average rate of 0.47 mgd
was 34.20/1000 gal.
  Excellent information on  cost  esti-
mates for small  water  systems is also
given in Reference 9.

Conclusions and
Recommendations

  1.  The nitrate  plant at Well No.  2 in
     McFarland,  CA, was successfully
     operated during 1985 and 1986 to
     provide the community with  343
     million gal (over the 2 yr) of drinking
     water  meeting the nitrate standard.
     This amount of water met 57% of
   the total demand for the commun-
   ity. On a  yearly basis, the plant
   produced 197.4 million gal (65.8%
   of the water) in 1985 and 145.58
   million gal (48.5% of the water) in
   1986.
   The capital cost for the McFarland
   plant was $355,638 (1983). Total
   annual cost for capital amortized
   over  20 yr at 8%  interest was
   $36,232. The average annual O&M
   cost  over  the  2-yr  (1985-1986)
   period was  $30,712. Based  on
   design capacity of 1 mgd, capital
   cost was 9.90/1000 gal and O&M
   cost was 8.50/1000 gal for a total
   cost of 18.40/1000 gal. The O&M
   cost  was 36% lower than pre-
   viously projected  and  total costs
   were  25% lower  than previously
   projected.
Table 1,    Plant Records August 1985
                    Gallons of Water
               Average Nitrate mg/L
                 in Blended Water
Gallons of Waste water


Date
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Total

To
System
854.000
907,300
907.300
907,300
867.000
933.000
900.000
957,000
879,700
879,700
879,700
905.000
902.000
925.000
953.000
926.000
906.000
906.000
912.000
948.000
955,000
274.000
931.300
931.300
931,300
1.250.100
473.500
473,500
921,500
921,500
954,500
27.172,500

Treated
by IX
608.200
636,600
636,600
636,600
604.700
640.400
636.800
657.200
605,200
605.200
605.200
627,100
618,900
649.100
708,300
829.600
623.300
623.300
626,800
650.700
650,600
189.000
434.200
434.200
434.200
1.250.100
322.400
322.400
621,700
621.700
627.100
18.737,400

By-
passed
245,800
270,700
270.700
270,700
262.300
292.600
263,200
299,800
274,500
274,500
274.500
277,900
283.100
275.900
244.700
96,400
282,700
282,700
285,200
297.300
304,400
85,000
497.100
497.100
497.100
--
151.100
151.100
299.800
299.800
327.400
8,435, 100
Gallons
Saturated
Brine
718
658
658
658
719
718
547
711
697
697
697
855
719
718
665
539
719
719
719
718
712
180
760
760
760
539
359
359
643
643
705
20,269


AsN03
27.0
25.6
--
--
28.0
27.6
29.0
31.0
30.0
--
--
29.0
27.0
29.0
28.4
29.4
30.4
--
27.4
25.6
27.4
31.0
29.8
-.
--
29.0
26.6
--
28.4
--
30.2
•28.5


AsN
6.11
5.80
--
--
6.34
625
657
702
6.79
-•
-
6.57
6.11
6.57
6.43
6.66
6.88

6.20
5.80
6.20
702
6.75
--
--
6.57
6.02
--
6.43
--
6.84
'6.45

Dilute
Brine
1,440
1.460
1.460
1.460
1.540
1,540
1.160
1.470
1.590
1,590
1,590
6.930
1.390
1.620
1.640
1.250
1.120
1,120
1.670
1.650
1.610
340
1,696
1.696
1.696
1.240
825
825
1,490
1.490
1.680
49.278

Slow
Rinse
11,560
14,173
14,173
14,173
14.420
12.310
12.930
14.420
14.286
14.286
14.286
18.030
14.420
14.420
14.420
10.820
ft. 920
11.920
19,420
12.790
13.830
5,830
13.526
13.526
13,526
14.170
7.215
7.215
12.620
12.620
14,420
407,675


Backwash
7.990
10.646
10.646
10,646
10.480
8.000
10.830
10.670
9.727
9.727
9.727
13,310
10.610
9.960
1 1.47O
8,110
1 0,465
10.465
10.520
7.190
10,520
5.380
9.743
9,743
9.743
10.210
5.240
5,240
9,080
9,080
12,960
298.128
Total
Gallons
Waste water
20,990
26,279
26.279
26.279
26.440
21.850
24.920
26.560
25,603
25.603
25.603
38,270
26.420
26.000
27.530
20.180
23,505
23,505
31,610
21.630
25.960
1 1.550
24,965
24.965
24,965
25,620
13,280
13,280
23,190
23.190
29.060
755.081
*Average value

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Table 2.
Month
1-84
4-84
5-84
6-84
7-84
8-84
9-84
10-84
11-84
12-84
1-85
2-85
3-85
4-85
5-85
6-85
7-85
8-85
9-85
10-85
11-85
12-85
Monthly An/on Analyses by Certified Lab (Mg/L)
Nitrate* Sulfate**
Raw
71
66
60
56
58
50
49
51
62
50
58
52
44
52
49
43
41
41
40
40
40
33
Treated
25
21
20
13
14
10
3
13
17
15
18
16
12
14
13
12
12
11
11
11
17
9
Blend
40
37
28
26
24
14
20
31
28
27
37
28
28
22
15
21
20
--
19
21
--
28
Raw
115
95
100
95
85
80
76
60
80
75
90
82
70
80
68
68
55
60
60
73
..
50
Treated
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Blend
34
38
16
27
21
0
17
36
28
26
42
29
32
17
0
21
20
--
22
19
..
31
Raw
104
113
100
87
70
69
75
80
82
78
88
78
76
81
75
67
66
63
60
77
..
67
Bicarbonate
Treated
100
21
38
75
57
61
43
21
47
70
85
12
48
90
22
13
17
10
21
23
..
62

Blend
102
38
80
50
67
55
49
50
54
45
63
57
65
64
17
46
44
--
36
47
..
65

Raw
88
84
77
75
74
68
58
60
62
59
90
57
55
61
60
53
50
49
47
63
..
46
Chloride
Treated
203
208
22
177
174
155
148
166
159
139
155
172
144
135
159
153
137
140
131
125
92
100

Blend
169
161
177
158
148
154
128
122
112
117
121
115
119
127
165
109
102
—
94
94
..
67
 'Concentration of nitrates are given as mg NO3/L
  To convert to mg NO3-N/L, divide values in above table by 4.43.
**0- less than 5.00.
Table 3.     Summary of Operating Data to January 1. 1986 Data

                           Salt Dose*
mg/L in Blend*


Month
6-84
7-84
8-84
9-84
10-84
11-84
Average
12-84
1-85
2-85
3-85
4-85
5-85
6-85
7-85
8-85
9-85
10-85
11-85
12-85
Average

Ib/ft3
of Resin
5.94
6.36
6.46
6.48
6.35
6.55
6.36
5.60
5.08
4.85
4.90
5.65
5.41
5.78
5.66
5.57
5.91
5.50
4.97
5.53
5.42
Service Batch Per Vessel (gal)
Prior to
11/6/85
11/6/85
12/12/85
1659.00x 100

2000.00
2500.00x 100

Ib/ 1000 gal
of Blend
2.01
2.42
2.89
2.69
2.10
2.82
2.49
1.78
1.74
1.85
1.68
1.95
2.24
2.21
2.04
1.97
1.99
1.91
1.71
1.48
1.89
BV
260.93

314.56
393.21

% Treated*
in Blend
66.20
74.00
87.20
80.90
64.50
83.80
76.10
61.70
6650
74.20
66.70
67.00
80.70
74.30
70.10
69.00
65.40
67.40
81.00
78.70
70.98







as A/03
21.20
22.30
24.70
23.40
23.80
23.20
23.20
24.30
26.60
28.10
25.70
21.40
26.70
24.80
26.10
28.50
25.20
25.30
25.50
25.40
25.66







as N
4.79
5.04
5.58
5.29
5.38
5.24
5.24
5.49
6.01
6.35
5.81
4.83
6.03
5.60
5.90
6.44
5.69
5.71
5.76
5.74
5.80






1000 gal
Delivered
5,307
3.595
3,002
4.245
4.738
3.771
4.110
12.402
7,826
16.845
6.615
5.837
6.070
19.462
21,481
27. 1 73
24.736
20.067
19.007
22.356
16.139





Cumulative
Million gal
Delivered
5.31
8.91
11.91
16.15
20.89
24.66

41.17
49.00
65.84
72.46
78.30
84.37
103.83
125.25
152.42
177.16
197.22
216.23
238.59






1/1/86 5-ft beds installed
*A verages per given month

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Table 4. Secondary Plant Performance Factors
Produced Water
(1000 gal)
Date
12-84
1-85
2-85
3-85
4-85
5-85
6-85
7-85
8-85
9-85
10-85
11-85
12-85
Monthly
Average
%of
Blend
%of
Treated
Blend
12,402
7.826
16.845
6.615
5.837
6,070
19.462
21.418
27. 1 73
24.736
20.067
19.007
22,356

16.139

100.00

140,38
Treated
7,647
5.201
12.492
4.415
3.910
4.900
14.467
15.009
18.737
16.168
13,527
15.392
17,593

11.497

71.24

100.00
Brine
(gal)
Saturated Dilute
8.322 13.220
5.132 13.722
11.781 30.576
4.205 15.430
4.295 8.180
5,148 15,154
16.238 41.441
16,500 37.646
20.269 49.278
18.553 81.917
14.448 33.585
12,295 37,078
12.500 45.932

11.514 32.550

.07 .20

.10 .28


Rinse
1.658
874
2.359
807
841
1.036
3.295
3.376
4.076
3.773
2.991
2.572
1.406

2.236

1.39

1.95
Waste water
(100 gal)
Backwash
725
573
1.372
521
563
875
2.536
2.424
2,981
2.655
1.980
1.649
967

1,525

.95

1.33


Total
2.516
1.584
4.036
1.483
1.487
2.064
6.246
6.178
7.550
7.248
5.308
4,592
2.833

4.087

2.53

3.55
Table 5. Other Plant Operating Data



Date
12-84
1-85
2-85
3-85
4-85
5-85
6-85
7-85
8-85
9-85
10-85
11-85
12-85

















Average
Brine Dose Per
Regeneration
(ga/r
179.90
163.10
155.89
157.43
181.54
173.64
185.54
181.72
178.82
189.68
176.56
183.85
180.69
A verage Setting of
Number of
Regenerations
During Month
46.26
31.46
75.57
26.71
23.66
29.65
87.52
90.80
1 13.35
97.81
81.83
66.88
69.18
Service Volume
Pounds of Sodium
Chloride Per Month
22.028
13.584
31.184
11.130
11.368
13.626
42.981
43.675
53.652
49.109
38.243
32,544
33,087















Per Month
(Bvr*
260
260
260
260
260
260
260
260
260
260
260
306
365
 "For 85 ft3 resin bed
"One BV = 635.8 gal
 3.  The plant actually processed 343
     million gal of water over the 1985-
     1986 period for an average of 0.47
     mgd. Based on the actual flow of
     0.47 mgd, 47% of design capacity,
     capital cost was  21.10/1000  gal
     (amortized over 20 yr at 8%  inter-
     est) and O&M cost was  13.1C/
     1000 gal for a total of 34.20/1000
     gal.
Over the 2-yr period of operation,
98.2% of the water pumped from
the well was distributed  to  the
system after  nitrate reduction to
approximately  6.8  mg  N03-N/L
The  1.8%  not distributed  was
discharged as wastewater.

The amount of wastewater  pro-
duced per 1000 gal of distributed
water consisted of 1.4 gal of brine,
6.6 gal of rinse water, and 10.3 gal
of backwash water.

The plant was operated with a 3-
ft-deep bed in 1985 and a 5-ft bed
in 1986. No differences in  perfor-
mance were observed which could
be attributed to the two different
depths.

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Table 6. Capital Costs, McFarland Well No. 2 Plant (1983)

Item 6'D x 6'H
IX. Vessels (3 included) $ 96.511
On-site Construction 81 .151
Brine Tank 18.700
Other 40.045
Resin 255 cu. ft (3 ft depth) 35.000
424 cu. ft (5 ft depth)
Sub Total $271,407
Engineering & Administration 15% 40,711
Total $311.118
*McFarland's Plant
Table 7. Operation and Maintenance Costs

Cost Item
Air Compressor
Hach Kits, Reagents
D.I. Water Service
Piping Supplies
Omega, Panel Repair
Meter Repair
Dionex Repair
AMA TEK. Batch Meter Repair
Grainger Compressor Repair
Heater Repair
Valve Actuator Springs
Compressor
Chemical Analyses
Telephone
Operator (1 hr/day @ $9.40/hr)
Engineering/ Operator Assist

Vessel Size
6'Dx 10'H*
$111.741
81.154
18.700
40.045

56.610
$309,250
46,388
$355.638


Dollars
1985
523.81
555.99
162.50
4.20
180.00
692.95
545. 15
161.35
21.60


391.40
494.50
120.16
3,420.05
6.000.00















1986

103.30
245.98

284.85

3.505.00
973.21

37.50
1.326.00

494.50
398.82
3.420.05
5.547.98
      Sub Total
               Annual Average
Production Related Costs
13,273.66
16,337.19
              14.805.42
Salt
Electrical
Sub Total
Table 8. Total Costs'
O&M Costs (1984/85)
O&M Fixed Costs
Electric $18.93 /mg
Salt $24.65 /mg
Sub Total
Capital Costs (1983)
$355.638 8% 20 yr
Total Costs
3.464.20
3.760.00
7.224.20
Annual
Costs
14.805.42
6.909.45
8,997.25
30.712.12
36,221.73
66.933.85
4,623.80
2.740.00
7,363.80
$/1000
gal
.041
.019
.025
.085
.099
.184
Average $ per
Million gal
Delivered
24.65
18.93
43.58
$/Acre-ft
13.35
6.19
8.15
27.69
32.26
59.95
"Based on design capacity of 1 MOD.

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  7.  The  amount of resin lost and
     lowering of resin capacity during
     the 3-yr of operation were too small
     to be measured. No resin replace-
     ment costs  are  included  in  the
     above O&M costs.

  8.  A significant finding  was  made
     which may affect future operation
     of the two nitrate plants in McFar-
     land. Data show that if the well is
     continuously pumped, the need for
     nitrate   treatment  decreases.
     Methods of managing well opera-
     tion  are being studied to use this
     information.

  9.  The  plant continued  to  operate
     automatically. Approximately 1-hr
     of time by a trained operator was
     required  to perform daily routine
     tasks. The operator was assisted by
     a remote telecomputer monitoring
     system  to  provide  expert  plant
     monitoring  and  assistance in
     adjusting the plant  for optimum
     operation.

10.  Nitrate analyses  were performed
     automatically every hour on a 24-
     hr day. These data were transmit-
     ted to a computer file  and to
     recording charts as permanent
     records.

11.  Experimental work was continued
     on development of resins with
     nitrate-to-sulfate  selectivity. One
     resin, a tributyl amine strong base
     resin,  showed unusually high
     selectivity. A United States patent
     was  issued on use of this resin in
     nitrate removal as a result of this
     work.

12.  Computer programs to simulate the
     ion exchange process were widely
     used during these studies.  The
     programs were useful in the devel-
     opment of nitrate selective resins
     and  in   assessing  plant  per-
     formance.

13.  The above costs do not include
     costs of disposing wastes from the
     plant. The composition of these
     wastes was determined and labor-
     atory studies  on their  reuse  by
     recycling were made.

14.  During the 1985-1986 period, over
     250 tons of salt were consumed in
     the nitrate removal process. The
     water containing these waste salts
     was disposed of to the McFarland
      sewer collection system where it
      was blended with raw municipal
      waste, treated  in aeration ponds,
      and disposed of to 120 acres of
      irrigated cotton crops.

 15.  The disposal of this large quantity
      of waste salt to the environment
      poses serious questions about the
      fate of these materials and their
      impact on the local environment.

 16.  Increases in TDS of the irrigation
      water were consistent with expec-
      tations. No water quality parame-
      ters changed significantly enough
      to affect the use of the water in
      cotton irrigation.

 17.  Soil chemistry changed slightly and
      showed increased sodium and less
      calcium.  The indices  used  show
      that a sodium-calcium equilibrium
      has been reached and no further
      changes are expected unless there
      is an  increased rate of  brine
      disposal.

 18.   There was a significant increase in
      nitrate content  of the soil water
      over the monitoring  period. This
      impact is being  studied by the city
      of McFarland to  see if fertilizer
      costs can be reduced.

 19.   Groundwater samples were taken
      from three different wells adjacent
      to the disposal area. Although
      there are indications  that waste
      salts  have  reached the ground-
      water table, there was no obser-
      vable increase  in nitrate or TDS
      levels in  the wells. It is expected,
      however, that ground  water dete-
      rioration will eventually occur.

 20.   Disposal of  wastewater  from  a
      nitrate plant remains a problem
      which will  intensify in McFarland
      when the second plant becomes
      operational. Monitoring of the
      disposal  area  should continue.
      Methods of recovery and reuse of
      wastewater salts need to be devel-
      oped to  reduce the discharge  of
     these materials to a minimum.

  The full report was submitted  in
fulfillment of  Cooperative  Agreement
CR-808902-02 by McFarland  Mutual
Water Company  under the sponsorship
of the U.S.  Environmental Protection
Agency. Boyle  Engineering Corporation
served as subcontractor.
References

1.  Guter, G. A.  Nitrate  Removal from
   Contaminated  Water  Supplies
   Volume I. Design and Initial Perfor-
   mance of a Nitrate Removal Plant.
   EPA  Report  under  Cooperative
   Agreement CR-808902-02-2.

2.  Guter, G. A. Removal  of Nitrate from
   Contaminated Water Supplies  for
   Public Use, Final Report. EPA/600/
   2-82/042, U.S. Environmental Pro-
   tection  Agency, Cincinnati, Ohio,
   1982.

3.  Guter, G. A. Operation, Performance,
   and Cost  of  the  McFarland,  CA
   Nitrate  Removal Plant.  In:  AWWA
   Seminar  Proceedings.  Control  of
   Inorganic Contaminants. Las Vegas,
   Nevada,  June 5, 1983,  No. 20175.
   pp. 29-49.

4.  Guter, G. A. Estimation of Resin and
   Water Composition on Column Per-
   formance in Nitrate Ion Exchange. In:
   AWWA 1984 Annual Proceedings,
   Dallas, Texas, June 10-14,1984. pp.
   1631-1649.

5.  Lauch, R. P. and Guter, G. A. A One
   MGD Ion Exchange Plant for Rem-
   oval of Nitrate from Well Water, in:
   AWWA 1984 Annual Proceedings,
   Dallas, Texas, June 10-14,1984. pp.
   713-733.

6.  Lauch, R. P. and  Guter, G. A.  Ion
   Exchange for the Removal of Nitrate
   from  Well  Water.  AWWA Journal,
   May 1986. pp. 83-88.

7.  Guter,  G.  A. and Hardan, D.  L.
   Computer Simulation of  Nitrate
   Removal by Ion Exchange. In: AWWA
   Annual  Conference Proceedings.
   Washington, D.C.,  June  23-27,
   1985. pp. 1293-1320.

8.  Guter, A. United States Patent  No.
   4,479,877  Removal of  Nitrate from
   Water Supplies Using a Tributyl
   Amine Strong Base Anion Exchange
   Resin. Issued Oct. 30, 1984.

9.  Gumerman, R. C.  et  al. Estimation
   of Small System Water Treatment
   Costs. EPA/600/2-84/184a, U.S.
   Environmental  Protection Agency,
   Cincinnati, Ohio, 1984.

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     Gerald Cuter is with Boyle Engineering Corporation. Bakersfield. CA 93302.
     Richard Lauch is the EPA Project Officer (see below).
     The complete report,  entitled "Nitrate Removal from Contaminated Water
       Supplies, Volume II.  Final Report," (Order No. PB  87-194 577/AS; Cost:
       $18.95, subject to change) will be available only from:
             National Technical Information Service
             5285 Port Royal Road
             Springfield. VA 22161
             Telephone: 703-487-4650
     The EPA Project Officer can be contacted at:
             Water Engineering Research Laboratory
             U.S. Environmental Protection Agency
             Cincinnati, OH 45268
United States
Environmental Protection
Agency
Official Business
Penalty for Private Use $300
EPA/600/S2-87/034
     BULK RATE
POSTAGE & FEES P
        EPA
   PERMIT No  G-3!

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