Report on Reevaluation  of  the

    1977 Effluent Limitations  for

        the Hilo-Hamakua  Coast

                of  the

           Island of  Hawaii

Raw Cane Sugar  Processing Subcategory
          Douglas  M.  Costle
            Administrator
          .Robert B.  Schaffer
Director,  Effluent Guidelines Division
           William M.  Sonnett
            Project Officer

             November  1979
     Effluent Guidelines Division
 Office  of  Water and Waste Management
 U.S.  Environmental Protection Agency
       Washington,  D.C.   20460
              3TERS LIBRARY
              MENTAL PROTECTION AGENCY
              '•'ON, D.C. 20460

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                               ABSTRACT

This report presents the findings of a study of the Hilo-Hamakua Coast
raw cane sugar processing subcategory for the purpose of  reevaluating
the effluent limitations guidelines for the subcategory.  The findings
are  in  answer  to the notice of suspension at 43 FR 43394, September
25, 1978.

The Agency is recommending revised effluent limitations guidelines for
suspended solids control.  These are based on the degree  of  effluent
reduction  attainable  through the application of the best practicable
control  technology  currently  available  (BPT).    This   technology
includes  screening  and  grit  removal,  clarification  with  polymer
addition, and settling in a clarifier followed by thickening and  land
spreading  of  the settled solids.  A series of gravity settling ponds
is reported to be a satisfactory alternative.

The  study  presents  the  supporting  data  and  rationale  for   the
recommended suspended solids effluent limitations.
                                                                        =,
                                                                         \


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                          TABLE OF CONTENTS
Section
I         CONCLUSIONS
II        RECOMMENDATIONS
III       BACKGROUND
IV        CURRENT STUDY
V         WASTEWATER TREATMENT SYSTEMS
VI        CANE HARVESTING AND WASTE LOAD
VII       BASIS FOR BPT LIMITATIONS
VIII      COSTS
Page
  1
  3
  5
  7
  9
 11
 13
 19

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                              SECTION I

                             CONCLUSIONS

EPA's review of the available data on waste treatment within the three
plants  in  the  Hilo-Hamakua  Coast  sugar   processing   subcategory
confirmed  that the technology originally recommended for the industry
is  still   appropriate.    This   technology   includes   end-of-pipe
clarification to remove suspended solids, vacuum filtration to dewater
the  settled  sludge,  and  land spreading to dispose of the thickened
sludge.

Review of the data indicates that the  original  BPT  total  suspended
solids  limitations  should be revised to better reflect the situation
at the Hilo-Hamakua Coast factories.  The  limitations  are  based  on
quantity  of  gross  rather than net cane processed.  The use of gross
rather than net cane more accurately accounts for the amount  of  soil
and  debris brought into the factories with the cane and the impact of
the soil  and  debris  on  the  process  wastewater  suspended  solids
loading.   The  pH  of  the  process wastewaters from the Hilo-Hamakua
Coast factories is not being controlled because of insufficient data.

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                              SECTION II

                           RECOMMENDATIONS

The Agency is recommending revised BPT effluent  limitations  for  the
Hilo-Hamakua Coast raw cane sugar processing subcategory based on end-
of-pipe  treatment  of  process  wastewaters and based on a gross cane
measurement of raw material.  The BPT technology is already  in  place
at  two  of  the three Hilo-Hamakua plants.  An alternative system, in
use at the third plant, is expected to be able to attain  the  revised
BPT effluent limitations set forth below.

                Maximum for Any One Day    Average of Daily Values
Effluent                                   for 30 Consecutive Days
Characteristics	Shall Not Exceed	

                   ko           Ib            kg           Ib	
                kkg gross  1000 Ib gross   kkg gross  1000 Ib gross
                  cane         cane          cane         cane

BODS                No limitations             No limitations
TSS~              9.9          9.9           3.6          3.6
pH                  No limitations             No limitations

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                             SECTION III

                              BACKGROUND

On  February  27,  1975,  EPA  promulgated  an  interim final effluent
limitations guidelines regulation for the  following  raw  cane  sugar
processing  subcategories:  Louisiana  (Subpart  D); Florida and Texas
(Subpart £); the Hilo-Hamakua Coast of the Island of  Hawaii  (Subpart
F);  Hawaii (Subpart G); and Puerto Rico (Subpart H).  Simultaneously,
the Agency proposed BAT limitations, standards of performance for  new
sources,  and  pretreatment  standards  for  existing  sources and new
sources.  A development document for interim final  regulation  and  a
supplementary  economic  analysis  of  the  possible  effects  of  the
regulation  were  issued  to  supplement  the   information   in   the
regulation.   The  Agency  requested  comments  on  the two supporting
documents.

On January 10, 1977, EPA suspended until March 1, 1978  that  part  of
the  interim final BPT regulation pertaining to the Hilo-Hamakua Coast
of the Island of Hawaii (Subpart F) so that EPA could  reevaluate  the
technical aspects.

The time frame of this initial suspension was insufficient to complete
the data collection and analysis, and on September 25, 1978 the Agency
extended  the  suspension of BPT regulation for this subpart until May
30, 1979.

The EPA has completed its review of all information relating  to  this
matter,  including  information  gathered  in  field investigations by
EPA's  National  Enforcement  Investigations   Center   and   industry
submissions.

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                              SECTION IV

                            CURRENT STUDY

On  July  31,  1978,  Region IX of the Environmental Protection Agency
requested new data from the industry under section 308  of  the  Clean
Water  Act.   The  data was to be used to re-evaluate best practicable
technology currently available (BPT).

Industry submitted information covering the development and  operation
of wastewater treatment facilities.  Included were descriptions of the
water  pollution  control  facilities,  data  covering waste treatment
performance and operation, and the capital, operation and  maintenance
costs  for  water  pollution  control  for  the Honokaa Sugar Company,
Hamakua Sugar Company (formerly Laupahoehoe Sugar  Company),  and  the
Hilo  Coast  Processing  Company,  Pepeekeo  factory.   Data  was also
provided on the soil and rainfall characteristics for the Hilo-Hamakua
Coastal area.

Additional engineering field evaluation  reports  were  completed  for
this  study  by  the  EPA  National  Enforcement Investigations Center
(REIC) in Denver.  These studies detailed plant investigations made by
NEIC during the  period  October  24  through  31,  1977.   Compliance
monitoring  reports and plant visit information also were submitted by
Region IX and the Hawaii Department of Health.

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                              SECTION V

                     WASTEWATER TREATMENT SYSTEMS

Total suspended solids (TSS) was the process wastewater  pollutant  of
most  concern in the initial BPT limitations.  Two distinct approaches
to the treatment of this pollutant have been taken by the three  Hilo-
Hamakua  Coast  factories.  Two of the mills, Honokaa and Hamakua, now
operate treatment systems consisting of preliminary screening and grit
removal, followed by  clarification  in  a  circular  clarifier  using
polymer flocculent aid.  Settled solids from the clarifier flow to two
vacuum  filters  for  thickening.   Sludge  is  retained in ponds when
solids loadings are too heavy for the vacuum filters to handle.  Final
treatment consists of land spreading the thickened solids.

The initial treatment design began operating at Honokaa in  July  1976
using  only  one  vacuum  filter, 10 feet in diameter by 20 feet long.
This proved inadequate to handle the settled solids  loading  produced
when the fine screens located ahead of the clarifier failed.

The  failed  screens  were  replaced  with a mechanical grit separator
consisting of a trough through which the wastewater flowed and through
which scraper boards passed.  The separator can remove about 8 percent
of the suspended solids compared with 50 percent removal by  the  fine
screens.   With  the  additional  solids passing to the clarifier, the
single filter could not handle  the  loading.   By  the  1978  growing
.season,  the  plant  had  installed mud ponds to receive underflow from
the clarifier to accommdate excessive solids load in the  system,  and
added  another vacuum filter to the system.  Treatment performance has
since been consistently reliable.

Hamakua's treatment system began operating  in  July,  1977,  complete
with  four  auxiliary mud ponds.  A second vacuum filter was installed
in May, 1978.  Treatment performance has been the best of any  of  the
mills.

The  Pepeekeo  factory  took  a  completely  different approach to the
treatment of process wastewater.  The company has a land treatment and
disposal system which consists of large settling ponds assisted  by   a
polymer  flocculant  aid.   Past  performance  of  the system has been
unrealiable, largely because of belated mud and silt removals from the
ponds and the incorrect location of the flocculant aid feed point.  To
correct these problems,   the  plant  has  expanded  the  pond  system,
acquired  additional  solids  handling  equipment,  and  relocated the
polymer feed point.

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10

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                              SECTION VI

                    CANE HARVESTING AND WASTE LOAD

Soil, the principal source  of  TSS  in  the  wastewater,  enters  the
factory  with the harvested cane.  The amount of soil brought into the
factory  is  a  function  of  the  harvesting  methods  and   rainfall
conditions prior to harvesting.

The basic harvesting methods use "push rake" and "V-cutter" bulldozers
with  heavy  rake-like  or  snow  plow-like  attachments.   These  can
function in the wettest conditions and in the  steepest  and  rockiest
terrain;  however,  they  also  pick up large quantities of soil along
with the cane.  In dryer weather and on  relatively  level,  rock-free
terrain,  more sophisticated mechanical harvesters can be used.  These
cut the cane with rotating knives and remove it with  much  less  soil
and  roots.   If  the  weather is dry, the cane can be burned, further
reducing the pick up of cane trash and associated soil.  All of  these
harvesting  methods  leave  rows  of piled cane which are subsequently
loaded into hauling trucks.  A more advanced harvesting method uses  a
mechanical  harvester  to  cut  the cane, clean and chop it into short
pfeces, and load it  into  a  buggy  which  is  driven  alongside  the
harvester.   Cane  harvested by this system does not need wet cleaning
at the mills.  However, numerous technical difficulties have precluded
large-scale application.  The mechanical  harvesters  are  not  usable
under wet conditions or on steep or rocky terrain.  In addition, push-
rakes  or V-cutters must clear strips around the borders of the fields
to give the harvesters room to maneuver.

Reducing non-mi liable material in  the  harvested  cane  provides  the
following benefits:

1.   reduction in the number of trucks required to  haul  cane  by  50
     percent;

2.   elimination  of  cane  cleaning,  the  most   expensive   factory
     operation;

3.   elimination of sugar losses of 15% or more from cane cleaning;

4.   reduction in factory milling costs by at least 50%;

5.   elimination of the need to dispose of over one million   tons  per
     year of waste material;

6.   reduction in power plant maintenance costs; and

7.   reduction of maintenance  costs,  from transportation through sugar
     storage.
                                  11

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12

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                             SECTION VII
                      BASIS FOR BPT LIMITATIONS
Background
The original effluent guidelines  study  for  the  Hilo-Hamakua  Coast
subcategory  defined  best  practicable  control  technology currently
available in the original Development Document, pages  191-192.   This
technology was based on engineering judgment, technology transfer, and
laboratory  information  developed  by  the  industry.  The technology
included  clarification  of  the  process  wastewaters  with   polymer
addition,  followed  by dewatering of the settled sludge, and disposal
of the thickened solids.   (Barometric  condenser  cooling  water  and
excess  condensate  bypass  the treatment system.)  The design assumes
grit removal, polymer addition and mixing, settling  in  a  heavy-duty
clarifier,  dewatering sludge by vacuum filtration, and land spreading
of the solids.

The use of gravity settling ponds for clarification is an  alternative
now  in use at the third factory.  EPA's review has shown that the BPT
technology on which the original effluent limitations  were  based  is
still  acceptable.   It is now in use at two of the three Hilo-Hamakua
Coast factories and is the basis for the revised guidelines.

The original BPT  effluent  limitations  for  the  Hilo-Hamakua  Coast
subcategory were as follows:
Effluent
Characteristics
                Maximum for Any One Day
                         Average of Daily Values
                         for 30 Consecutive Days
                         Shall Not Exceed
kq
kkg net
cane
Ib
1000 Ib net
cane
ko
kkg net
cane
Ib
1000 Ib net
cane
BOD5
TSS
pH
  No limitations             No limitations
4.2          4.2           2.1          2.1
   Within the range 6.0 to 9.0.
Revised Limitations and Rationale

EPA   is  revising  the  BPT  effluent limitations for the Hilo-Hamakua
Coast subcategory as  follows:
Effluent
Characteristics
                Maximum  for Any One Day
                         Average of Daily Values
                         for 30 Consecutive Days
                         Shall Not Exceed
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                   kg           Ib	      kg           Ib	
                kkg gross  1000 Ib gross   kkg gross  1000 Ib gross
                  cane         cane          cane         cane

BOD5_                No limitations             No limitations
TSS               9.9          9.9           3.6          3.6
pH                  No limitations             No limitations

The revised effluent limitations are less stringent than the  original
ones,  use gross rather than net cane as the production parameter, and
do not limit pH.

EPA developed the revised  limitations  from  operating  data  at  the
Honokaa  and  Hamakua  factories where BPT is in place.  The data came
from discharge monitoring  reports  submitted  by  the  companies  and
contained  in  compliance  monitoring  reports  provided by the Hawaii
Department of Health.  The Agency reviewed records from March  through
December,  1978,  for Honokaa, and July 1977 through December 1978 for
Hamakua.   Monitoring  data  for  May  through  December  1978,   were
considered for Pepeekeo.  The expanded ponds began operating in May.

ThU  treatment  plant  effluent  data  for  the  three  factories  are
summarized below.

                               Honokaa

                 TSS (kg/kkg or lb/1000 Ib gross cane)
                     Maximum Day      Monthly Average

March, 1978              2.0               1.56
April                    7.37              2.96
May                      1.61              0.74
June                     2.83              0.98
July                     2.01              1.53
August                   1.21              0.77
September                4.95              2.29
October                  2.40              1.57
November                 4.00              2.85
December                 8.07              5.01

                               Hamakua

July, 1977               1.04              0.64
August                  10.8               2.8
September                0.74              0.51
October                  1.4               0.71
November*                1.32              1.13
March, 1978              0.35              0.27
April                    0.70   '           0.54
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May                      0.75              0.32
June                     1.99              0.89
July                     4.42              1.4
August                   0.5               0.39
September                2.83              1.50
October                  2.60              1.42
November                 7.83              3.60
December                 5.04              2.24

*Consists of a combination of 2 values for Nov., 1 for Dec. and 2 for Feb.;
 these were the only values reported for these months.

Except for one monthly average and one daily maximum value, all of the
values for the two factories are less than  the  revised  limitations.
The  high monthly average resulted from one unusually high daily value
for which no explanation was reported.

                               pepeekeo

Rebuilt ponds treating the waste from this factory began operating  on
April  26, 1978.  Several months of effluent data for this system were
as" follows:

                 TSS (kg/kkg or lb/1000 Ib gross cane)
                     Maximum Day      Monthly Average

May, 1978                3.85              2.18
June                    12.45              5.08
July                     9.60              6.17
August                  39.16             18.52
September               27.52             12.56
October                 35.78             15.64
November                55.69             20.58
December                35.83             19.81

The plant met  the  revised  limitations  during  the  month  of  May;
thereafter,  the  monthly average and maximum-day values increased and
are considerably higher than the  revised  guidelines.   As  indicated
previously,  this  system  has  not  operated reliably,- however, plant
engineering  personnel  state  that   when   properly   operated   and
maintained,  the system achieves average TSS values of 7.15 Ib TSS per
1,000 Ib of net cane.  This is equivalent to meeting the  revised  BPT
limitation  of  3.6  Ib  per  1,000  Ib  gross cane because gross cane
typically is 50 percent  debris  or  more.   Under  optimum  operating
conditions,  EPA  Region  IX,  NEIC,  and  State  of  Hawaii personnel
determined that the system produces an  effluent  quality  similar  to
BPT.
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                              Gross Cane

The  Agency  has  adopted  gross  cane  rather  than  net  cane as the
production parameter because it provides a  more  accurate  method  of
determining  effluent  loadings.  Industry data show variations in the
wastage in the gross cane trucked to the factories.  These  variations
regularly occur because of differences in harvesting methods, terrain,
soil  types,  efficiency  of  cane  burning,  the  use of ripeners and
defoliators  prior  to  harvest,  operator  skill  in  using   infield
equipment,   and   variations  in  rainfall.   This  latter  point  is
particularly significant.  During periods of  high  rainfall,  records
show  that  soil  and debris may comprise as much as 70 percent of the
material delivered to the factory.

The use  of  gross  cane  as  the  production  parameter  takes  these
conditions  into  account.   Gross cane is weighed upon arrival at the
factory, and because it includes both debris  and  cane,  it  is  more
representative  than net cane (an estimated quantity) of variations in
the amounts of extraneous  materials  and  the  attendant  waste  load
imposed  on  the wastewater treatment facilities.  The fluctuations in
waste load affect waste  treatment  plant  performance  and  attendant
solids  effluent  levels.   This  is  the rationale for the gross cane
parameter.

                                  pH

The original limitation of pH to between 6 and 9 also was reviewed  in
this  study.   Industry  comments stressed the fact that the naturally
acidic  nature  of  the  Hilo-Hamakua  Coast  plantation   soils   was
responsible  for  low  process  wastewater  pH  values.   A  study  by
consultants Sun, Low, Tom, and Hara showed strongly  acidic  soils  in
the  region  of  the  Hilo-Hamakua  Coast plantations, as shown in the
following table.

          Plantation
          Soil Type            pH

          Akaka                5.5

          Hilo                 4.3

          Honokaa              6.0

          Kaiwiki              4.9

          Kukaiau              4.5

          Ookala               5.0
                                 16

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          Paauhou              5.5

Available pH data for the process wastewaters  from  the  Hilo-Hamakua
factories were very limited, but demonstrated the acidic nature of the
wastewaters.   Information from Honokaa and Hamakua covered only a few
days of operation.  Hamakua reported pH  values  as  low  as  5.2,  at
Honokaa,  pH  values  for five days of operation in 1975 were given as
follows:

Date                         pH Range

May 19                       5.3 - 6.1
May 20                       5.9-6.6
May 21                       5.4-6.5
May 22                       5.9-6.5
May 23                       5.4-6.9

To modify the naturally occurring pH of the wastewaters would  require
the addition of an alkaline material such as chemical lime; because of
the  voluminous  quantities of wastewaters involved, raising the pH to
the usually accepted minimum of  6  would  require  large  amounts  of
ctie'mical.

Consideration  of  these  factors  convinced the Agency that data were
insufficient to set a specific pH limitation.  Therefore,  the  Agency
will not promulgate a pH limitation at this time.
                                  17

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                             SECTION VIII

                                COSTS

Two  of  the Hilo-Hamakua Coast factories have BPT technology in-place
and in use; the third factory, which uses an  alternate  gravity  pond
system, has all the necessary equipment to effect treatment.

EPA  has  identified  the  following additional costs for manpower and
basic equipment to insure adequate operation and  maintenance  of  the
pond system.

     Equipment                          Cost*

1.   One D~3 Backhoe tractor to remove                                        I
     silt from ponds (at least one
     is already in use)                 $43,704

     Manpower

2.   Two additional land containment
.  *"*  dredge operators                   $37,775


*January 1, 1979 dollars
                                                                             l

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The costs developed for BPT are listed below and cover the following equipmen
secondary screens; clarifier; water pipes; pumping; polymer feed system;
vacuum filters; soil conveyance; and storage and trucks.
These figures represent costs for a plant
with in-place technology but no BPT waste treatment facilities.
This is the case for the one Hilo-Coast factory which has
substituted a ponding system for the BPT technology.
All costs have been adjusted to January 1, 1979 dollars.

          Treatment Level           Capital Costs*
            BPT (1977)$1,874,000

Specific equipment costs are as follows:

          Secondary screen**                    129,600
          Clarifier                             432,500
          Water pipes, pumping, etc.             19,400
          Polymer feed system                    79,500
          Vacuum filters                        416,700
          Soil Conveyance and Storage           351,400
          Trucks                                445.000
                                             1,874,100
* January 1, 1979 dollars
**Secondary screening or some substitute.

     Operating Costs*

     Secondary Screen Maintenance                 2,650
     Water Pump Maintenance                         390
     Polymer Feed System
     - Operation and Maintenance                 29,500
     - Labor                                     29,900
     Clarifier - O&M                              5,800
     Vacuum Filters
     - Maintenance                               11,600
     - Labor                                     19,800
     Soil Conveyance and Storage
     - Maintenance                                6,710
     Trucks
     - O&M                                       28,080
     - Labor                                    205,840
     Power                                       15.360
                                               355,630

     Land  $0/yr - $31,200/yr.

*January 1, 1979 dollars
                                  20

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