.PRODUCTION OF NON-FOOD-CHAIN CROPS
         •  WITH SEWAGE SLUDGE
                    by
        	Lilia A. Abron-Robinson.
               Cecil Lue-Hing
          PEER Consultants, Inc.
              Edward J. Martin
               David W. Lake
    Environmental Quality Systems, Inc.
        Rockville, Maryland  20852
          Contract No. 68-03-2743
              Project Officer

               Gerald  Stern
Municipal Environmental Research Laboratory
              Cincinnati,  Ohio
MUNICIPAL ENVIRONMENTAL RESEARCH LABORATORY
     OFFICE  OF  RESEARCH  AND  DEVELOPMENT
    U.S.  ENVIRONMENTAL PROTECTION AGENCY
             CINCINNATI,  OHIO

-------
     This  reports  has been  reviewed by  the Municipal  Environmental Research
'Laboratory,  LT..S,:  Environmental  Protection Agency, and  approved for publica-
Ition.   Approval*  does  not  signify  that  the contents  necessarily reflect the
(views  .and'  policies of  the U.S.  Environmental  Protection Agency,  nor does
.mention of  trade  names or commercial products  constitute endorsement or  recom-
imendation for use.

-------
                                   FOREWORD ..
    The U.S. Environmental Protection Agency was created because of increasing
public and government concern about the dangers  of pollution to the health and
welfare of the American people.  Noxious air, foul water, and spoiled land are
tragic testimonies to the deterioration of our natural environment.  The  com-
plexity of  that  environment and the  interplay of  its components  require  a
concentrated  and  integrated attack on  the problem.

    Research and development is that necessary first step in problem solution,
and it involves defining the problem, measuring its  impact, and searching for
solutions.... The Municipal Environmental Research Laboratory develops new and
improved technology  and systems to prevent,  treat,  and manage  wastewater and
solid and hazardous  waste pollutant discharges  from  municipal  and community
sources, to preserve and treat public drinking water supplies, and to minimize
the adverse economic, social, health, and aesthetic effects of pollution.  This
publication is one of the products of that research  and provides a most vital
communications link  between the researcher  and  the user community.

    The utilization  of sewage sludge  as~ a resource has been proposed by the
U.S. Environmental Protection Agency.  In this regard, this study examines the
feasibility and market potential for  the production  of non-food-chain crops
with sewage sludge.
                                             Francis T.  Mayo,  Director
                                             Municipal Environmental
                                             Research Laboratory

-------
                                 	ABSTRACT	
                                       i -
                                       i -
                i                       '                                       *
                !                       '  -*                                    1
     Feasibility.and market potential  were determined for non-food-chain crops!
 cultivated  using  sewage sludge.        i
                i                       i                       •
:     Non-food-chain crops that are currently being sold  on  the  open market or
 that have a. good potential for marketability were selected.   From a list of 20j
!crops,  3  were selected and subjected to  a cost  analysis to determine how the!
:costs for cultivation using sewage sludge compared with the  costs for cultiva-j
 tion using  commercial  fertilizer.      j                                       I
•                I                       i               •            .       •     i
:  _  Cotton, _socU   and.  energy  biomass trees  were_determined_ tq_Jiave__the[.best]
 potenti al~Tor cultivation using  sewage;studg~e"i  based on  the~market'values "and1
 nutrient requirements  for each crop, and on the hectares presently under culti-j
 vation  for  production  of these crops.  '                                       I
•                ;                       I                                       !
:     Results indicate that large  quantities of sewage sludge can be used, based:
 solely  on the nitrogen and phosphorus requirements for the cultivation of these;
 crops.    In addition,   it was determined  that  although  the total  costs  for
 fertilization using commercial  fertilizer are  less  than the costs  for using!
 sewage  sludge, the  latter would be  viewed  more favorably  if  the  costs were.
 borne by  the municipality generating the  sludge.                '             j
                \                       ',                                       I
     This report was  submitted in fulfillment of  Contract  No. 68-03-2743 by PEER;
 Consultants,  Inc.  and-Environmental Quality Systems,  Inc.  under  the sponsor--
 ship of the  U.S. Environmental  Protection  Agency.   This   report  covers the-
 period  October 1,  1978 to December 1979, and work was completed as of May  1980. 1
                                       IV

-------
                                  CONTENTS
Foreword	'	     i i i
Abstract	      iv
Figures	      vi
Tabl es	     v i i
Abbreviations and Symbols	       x
Acknowl edgements	     xi i

    1.   Introduction	       i;

    2.   Conclusions ...	       2

    3.   Recommendations	       4

    4.   Fertilizer and Energy Value of Municipal Sewage Sludge 	      5
              Introduction..;	*       5
            "  Quantity of sewage sludge generated by POTW'S	       5
              Plant nutrients in sewage sludge	       6
              Energy requirements	      11
              Summary	      13

    5.   Methodology for Selection of Non-Food-Chain Crops	      15

    6.   Non-Food-Chain Crops Amenable to Cultivation
           Using Sewage. Sludge	      19
              Discussion of potential crops 	      19
              Most promising non-food-chain crops	      50

    7.   Case Studies	      53
              Methodology	;	      53
              Case study 1: cotton production	      62
              Case study 2: sod production	      69
              Case study 3: biomass production 	      72
              Summary	      73

    8.   Cost Analysis	      75
              Background	•	      76
              Discussion and summary..	      78

References	      90

-------
                                  FIGURES
Number                              .                             rage

 1       States with significant cotton
           producti on	    48

 2       States with significant soybean
           producti on	r	    49
              !                      ;
              i                      !   .      .       -
 3     _ States, with .significant sod.producti^n	_/.	_ 55

 4       Millions of acres and percentage of land
           potentially available for energy biomass
           tree production by region (assuming the
           utilization of 10% of the non-agricultural
           land in each region)	    56

 5       Costs of land application of sludge by
           injection	    63

 6       Costs of sludge application by surface
           irrigation	    64

 7       Costs of truck-spreading liquid sludge	    g5

 8       Costs of liquid sludge transport - 20 miles	    84

 9       Costs of liquid sludge transport - 40 miles	    85

10       Costs of liquid sludge transport - 60 miles...,	    gg

11       Costs of sludge cake transport - 20 miles	    gy

12       Costs of sludge cake transport - 40 miles  	,^_  Pp
                      j            r           .     ..    .....^—  JJQ

13       Costs of sludge cake transport - 60 miles	    gg
                                    vi

-------
                                 .  TABLES


Number                                                             Page
 6       N, P, and K Values for Primary Sludges
                                             .
10       Comparisons of Energy Requirements for the
           Production of Inorganic Nitrogen
         Major Plant Nutrients Present in Various
           Sewage Sludge Sources, Percent Dry
           Weight .............................................       6

         N, P, and K Levels in Anaerobic and Aerobic
           Digested Sludges ...................................       7

         Nutrient Content -of Sewage Sludge Before and
         .-After-Wet Air Oxidation ..... .......... ..v... ....... ...... —  3

         Impact of Lagooning on the Nitrogen Content
           of Sludge .................. ........................       8

         Nitrogen Content of Sludge Before and After
           Heat Drying ....................................... .       3
 7       Nutrient Content of Two Waste-Activated
           Sludges .............. ... ...........................      g

 8       Nutrient Content of Various Dewatered
           Sludges ..................................... .......     j.0

 9       Daily Value and Costs of Nutrients Contained in
           Municipal Sludge ...................................     IQ
11       Comparisons of Energy Requirements for the
           Production of Inorganic Phosphorus ...... ...........     12

12       Comparisons of Energy Requirements for the
           Production of Inorganic Potassium ..................     12

13       Energy Requirements and Costs for Total
           Municipal Sludge Incineration ......................     13
                                    vii

-------
Number         ;                       !  - f                        Page
               i                       j
14       Categories of Non-Food-Chain Crops Selected
           for Study	•	      16
               !                       ••
15       Possible Non-Food-Chain Crops' Amenable to
           Cultivation Using Sewage Sludge 	      18
               i                       I   •
16       Types .and Distribution of Deciduous Trees
           (Hardwoods) in the United States		      21
               i     _,/«..             j           _^

17       Nutrient Requirements for a Conventional
           Forest and Nutrient Application Rates for
           Forest Crops	\	      29
               !              •         \

18       Types1and Distribution of Coniferous Trees
           (Softwoods) in the United States	      34
               i                       i
19       Non-Fobd-Chain Crop Uses for Cotton and
           Soybeans	;	      46
                                      i
               :                       i
20       Kilograms of N, P, and K Applied to Cotton
           and Soybeans 	;	      50
               r                       !
21       Most Promising Non-Food-Chairt Crops Suitable
           for Cultivation Using Sewage Sludge 	      51
               i                       i
22       Cost of Applying Liquid Sludge to Provide
           Nitrogen for Cotton Cultivation 	      66
                                      !
23       Cost of Applying Liquid Sludge to Provide
           Phosphorus for Cotton Cultivation 	      67
               i                     •  I •
24       Cost of Applying Liquid Sludge to Provide
         ,  Nitrogen for Sod Cultivation	      70
               i                       i
25       Cost of Applying Liquid Sludge to Provide
           Phosphorus for Sod Cultivation	;	      71
               ,                       i
               i                       i
26       Cost of Applying Liquid Sludge to Provide
           Nitrogen for Biomass Cultivation 	      74

-------
                             TABLES (continued)
Number                                                            Page

27       Cost of Applying  Liquid Sludge to Provide
           Phosphorus  for  Biomass Cultivation .................   75

28       Cost Comparisons  for  Sludge and Commercial
           Fertilizer  ................ . ... .....................
29       Cost Comparisons  for Sludge vs. Commercial
 ,  - ...... - ....... Fertl 1.1 zer; .v. .-« .--.--. , . . ... .V. . .-. •; -r. ... .^ .-. — . .-. ;-.- --QI
                                      IX

-------
                        ...ABBREVIATIONS AND .SYMBOLS
ABBREVIATIONS

Btu
CAST
cm
d
DMTE
DMT
DT
ft,
ft* ~	

gal
ha
hp
J
Kcal
Kg
kJ
kl
KW
1
LA/OMA
Ib
M3
MJ
mil
ml
mm
MOP
MSC
MSDGC
MT
NFCC
POTW
SIC
WAO
WPCF
yr
   British thermal unit
   Council for Agricultural Science and Technology
   centimeter
   day
   dry metric ton equivalent
   dry metric ton
   ;dry ton               ;
  _feet ......
   square f eet~
   cubic feet
   gallon
   hectare(s)
   horsepower             ;
   joule
   kilocalories
   kilogram
   kilojoule
   kiloliter
   Kilowatt
   liter
   Los Angeles/Orange County Metropolitan Area
   pound
   meter
   square meter
   cubic meter
   mi 11ion
   mi Hi liter
   millimeter
   Manual of Practice
   Milwaukee Sewage Commission
   Metropolitan Sanitary District of Greater Chicago
   metric ton
   non-food-chain crop(s)
   publicly owned treatment works
   Standard Industrial Classification
   wet air oxidation
   Water Pollution Control Federation
— year

-------
^.SYMBOLS
                     ABBREVIATIONS AND SYMBOLS (continued)
  K         — potassium
  ICO       — potassium oxide
  N         — nitrogen
  NIU       — ammonia                 ;
  NPK       — nitrogen, phosphorus, potassium ratio
  P         — phosphorus              •
  PoOr      — phosphorus pentoxide
  3T        — percent

-------
                             __AC.KNQWLEp(3MENTS.,

                i                       '                                       i
     The assistance of the many Federal  agencies  and private corporations and:
 businesses is gratefully acknowledged.   Also,  the cooperation and overall pro-'
;ject coordination  by  Mr.  Gerald Stern  (EPA Municipal  Environmental Research;
;Laboratory,  Cincinnati,  Ohio) as the Project Officer is appreciated.         i
                :                                                              i
                                                                              <
;     The  project   investigators  wish  to  express  their  appreciation  to MsJ
 Beverly Preston,  Ms.  Sharon Fried, and Ms. Susan Orye who spent many hours on;
ithe manuscript preparation.   The project investigators  are  also indebted to,
!their colleagues  for their  assistance 'and suggestions  during the development:
;of the information presented in this report.                                 j
                                      xii

-------
                               ACKNOWLEDGMENTS
|     The assistance of the many Federal  agencies  and private corporations and;
[businesses is  gratefully acknowledged.;  Also, the cooperation and overall pro-:
;ject coordination  by  Mr.  Gerald Stem  (EPA Municipal  Environmental  Research!
iLaboratory,  Cincinnati,  Ohio)  as the Project Officer is appreciated.           j
'      '          [                       ;                                        •'
\     The  project   investigators  wish  to express  their  appreciation to  Ms.j
JBeverly Preston,  Ms.  Sharon Fried,  and!Ms.  Susan Orye who spent many hours on!
;the manuscript preparation.   The project investigators  are  also  indebted to;
{their colleagues  for their assistance :and suggestions  during the  development,
jof the information presented in this report.                                  !
                                      XII

-------
                                  JEGHQJLL
                                  INTROdUCTION
[BACKGROUND
•     About a quarter of the  stabilized  sewage sludge produced by publicly ownedj
•treatment worksj (POTW)  in  the United States  is  disposed of  directly  to thej
 soil.   Increasing  restrictions on alternative sewage  disposal  practices andj
1 increased sludge production  because of  implementation of the  Federal  Water!
[Pollution Control  Act  Amendments  of 1972 (PL 92-500)  will  result in greatlyi
\increas^djqujjntlties^of .^sewage^sjudge  tieing appl_ied__to__the_land, furthermore,t
"it "is a  valuable  resource~~biec:ause" of^lts" nutrient  and  organic content, andl
: increasing emphasis will be placed on beneficial  uses of sewage sludge simul-
 taneously with land disposal  practices  for  sewage sludge.  The prospects ofj
.widespread 1 and'•. application of sludge,-however,  have caused increased concern;
;over possible-accumulation  of  toxic substances (e.g., heavy metals, pesticides;
|and other organics, and pathogens)  in  soils.  The translocation of these toxicj
isubstances to growing crops,  fodder used in  silage, and to pastures is poorly!
:understood.  Even  less information is available on the translocation of thesei
;toxic  substances  throughout  the  direct food  chain to  animals  and  humans.j
'Another approach, then,  is to use sewage  sludge for the cultivation  of non-food-]
.chain  crops (NFCC).  This beneficial use  of the sludge could perhaps circumvent:
•the problems associated with  the unknown impacts  of the toxic materials in the
;sludge on the food chain.             I
:       '      •   1    •                   !
i     The  literature  is  replete  with  documented  experiences on  the application
[of sewage sludge to  agricultural land, and there are some studies involving the!
[reclamation of .[disturbed lands (e.g.,I strip mine  areas)  with sewage sludge.j
'The data base  for  guidance concerning!  application  of  sewage  sludge  to land!
icomes'from these  studies.   Pietz et  al.   (1)  and the  U.S.  Department of!
;Agriculture (USDA)  (2), as well  as many others,  have shown that it is technically!
'and economically feasible  to  land  spread  sewage sludge  on  agricultural and!
[disturbed land.;  Therefore, it  is  worth considering  the  possibility that the!
 production of NFCC  is  also  technically [and economically feasible.  If this werel
'found  to  be true,  perhaps it would be possible to permit large-scale applica-j
 tions  of  sewage.sludge to the  land  for[beneficial purposes without the concern!
[of increasing levels of toxics in the human  food chain.

 Objectives     ,
:                i
     The  primary;objectives  of this study were to evaluate the feasibility and
[market potential  for land application of sewage sludge for the cultivation of

-------
                                  SECTION 2

                                 CONCLUSIONS


     The following conclusions have been made as a result of this study:

 1.  The non-food-chain  crops  (NFCC)  with  the best apparent feasibility for
     production using sewage sludge are:

     1.   Softwoods amenable to monoculture operations
     2.   Forest nurseries
     3.   Horticultural specialties
     4.   Energy biomass trees
     5.   Oil crops such as cotton and soybeans

 Though cotton  and  soybeans do not fit  the  definition of NFCC, it was felt
 that the inedible products from these crops were sufficient to warrant .their
 inclusion in this report.

 2.  Based on the criteria developed for this study, sod, cotton, and energy
     biomass trees were selected as having the best apparent feasibility and
     market potential.

 3.  Of the three crops considered, utilization of sludge for sod production
     is the most feasible at this time.  Sod production would use, conserva-
     tively, 5% to 10%  of  the total  sludge  generated  in the sod producing
     states.

4.   Based on only the three crops presented here, at  least 20% of the  total
     sludge generated could be used for  growing NFCC.

5.   The variations  in  cost for sludge application among geographic regions
     in the United States for  the three  crops examined are small compared  to
     variations based on the method of application and crop type.

6.   The costs of sludge application to biomass trees and in some cases cotton
     using the truck-spreading option compare favorably to the costsvfor com-
     mercial fertilizer.

7.   Transport  costs  for sludge can  range from 1.5 to  7 times the cost  of
     sludge  application  for the cases studied  based  on  a one-way transport
     distance of up to sixty (60) miles transporting  liquid  sludge  and sludge
     cake.   Transport  costs   vary  between about  $27/dry metric  ton  (DMT)
     ($25/dry  ton  (DT)) for  sludge  cake  to  $110/DMT  ($100/DT)  for  liquid
     sludge.

-------
8.   Using sewage sludge for the production of NFCC could  be the  least  costly
     alternative for sludge disposal  by a POTW, particularly if a  cost benefit
     is derived  by  also  recovering damaged or upgrading non-productive  land
     to produce the NFFC.

9.   To promote the use of  sewage  sludge for the production of NFCC, most  of
     the costs  (transportation  and application) associated with the use  of
     this material  should  be borne  by  the municipality  generating the ma-
     terial.

-------
                                  SECTION 3

                               RECOMMENDATIONS
 1.   Research centered on the production of new and unusual crops such as the
:     jojoba,  euphorbia,  and guayule should  include  the use of sewage sludge as
     a  source of nutrients or as a growing medium.

;2.   Non-food-chain uses  for  cotton and soybeans  are great,  and these crops
•     have high N requirements.  Thus a management system  should be developed to
     permit the  use of sewage sludge for the  cultivation of  a portion of those
     crops on a national basis.  This management system would insure that those
  •  "crops would not be used" for 'food-chain" products! ~~          "	~

'3.   The costs for sludge  application  to NFCC  should be studied in detail to
;.     bring the comparison  with  commercial  fertilizer into sharp focus.  Good
     cost estimates will  assist in  making the decision to use sludge  on  NFCC as
•     an alternative to commercial fertilizer or to enhance  growth conditions.

-------
                                  SECTION 4

           FERTILIZER AND ENERGY VALUE |OF MUNICIPAL SEWAGE SLUDGE
 INTRODUCTION    :                       '.

     The most common disposal technologies in use for POTW sludges are not based
.on the fact that this material is a recoverable resource, but that it is a spent
 resource  with  no further value.  However, new technologies  are being developed
 which  emphasize' reuse  of  the minerals  and organic  matter present  in  POTW
•sludges.   As with  any new  technology, the benefits and drawbacks of the tech-
 nology must be carefully.studied in order to make a determination of worth.  It
 has "been  demonstrated" many timesthat the nutrient contenfof POTW "slutJges "can"
 be used for crop production, and  it has been suggested that these nutrients be
 used to supplement  that provided by chemical fertilization.  The sludge also has
 soil conditioner value.  This suggestion has merit especially when the costs of
 production of.the.nutrients are compared.                             -
              ""'"'".                      i
     If POTW sludges can be used for plant production by supplying the adequate
 nutrients necessary for growth, then the availability of this material should be
 known  and estimates  of its nutrient  value should  also  be known.  In addition,
 the  value (both as a nutrient  supplier and the economics  of  production and
 application) of this material should be compared with  the value  of the primary
 material  most commonly in use.  Once the  above facts are known, then the user is
 in  a better position  to determine the preferred  product for use.
                i                       j
     This  section gives an estimate of the quantities and nutrient value of POTW
 sludges.  Also, the quantities of chemical fertilizers  that  must  be produced to
 supply the plant nutrients present in POTW sludges were calculated for purposes
 of looking at the energy costs involved.'  Lastly,  the amount of energy required
 to chemically  produce the nutrients contained in POTW sludges was compared with
 the  energy required  to incinerate (destroy)  these sludges.  This was done to
 explicitly show possible energy savings when beneficial POTW sludge usages are
 considered.  This  information  puts  in perspective the nutrient value of POTW
 sludge in relation to equivalent amounts of chemical  fertilizer,  the energy
 needed to produce an equivalent amount of chemical  fertilizer and the amount of
 energy needed  to destroy the sludge.  Energy costs are discussed below.

 QUANTITY  OF SEWAGE SLUDGE  GENERATED BY;POTW'S

     National  sludge production figures  are  difficult to estimate,  but there
 are  many  estimates given in the scientific literature.  Dean (3) estimated the
 actual national sludge  production  in  1972  to  be approximately 9,072  DMT/d
 (10,000 DT/d)  and  by 1990  the estimated quantity would be nearly 11,794 DMT/d:
 (13,000_DT/d)_.	The_CgunciJ__for Agrjcultural  Science and Technology (CAST) (4)

-------
estimated municipal sludge production to be 8,115 DMT/d (8,945 DT/d) for 1970 and
that this would increase to 16,456 DMT/d (18,140 DT/d) by 1985.  Thus, there are
considerable differences in the quantities  of municipal sludge as estimated by
Dean and CAST.

    The Water  Resources Council  (5)  estimated  that  the  sewered  population in
1970 was 135 million (mil), while for 1985,  176  mil is projected.   The estimate
was based on the U.S. population being served by sewers as 67% in 1970 and 75% in
1985.  Farrell  (6) estimated that the  per capita daily raw sludge production was
0.055 Kg  (0.12  Ib)  for primary plants  and.0.091 Kg  (0.20  Ib)  for primary and
secondary plants.   The degree  of  treatment obviously impacted sludge produc-
tion.

    If  it  is   assumed  that  in  1970,  50% of  the  U.S. sewered population  was
served only by primary and secondary plants  and that the  other 50% was served by
primary plants, then the annual sludge  production would be 9,843  DMT/d  (10,850
DT/d).  For 1985,  assuming that all municipal  plants  had primary  and secondary
treatment, the annual  sludge  production would rise to 16,012  DMT/d  (17,650
DT/d).  The sludge production estimates used for these senarios are reasonable
when compared  with  the estimates  given  by  Parrel! and  CAST.	~

PLANT NUTRIENTS IN  SEWAGE SLUDGE

    Municipal  sludge is derived from the organic and inorganic matter removed
from wastewater at  sewage treatment  plants.  The  amounts  of the constituents
present will  depend upon the wastewater sources  and the method of wastewater and
sludge treatment.

    Municipal  sludge  contains  significant amounts of N,  P, and K as well as
other plant nutrients. Table 1 shows the data of Zenz et_  jj]_.  (7) and Sommers
et jj]_. (8).   Zenz et _al_.  (7) collected samples from 24 plants in the state of


      TABLE 1.   MAJOR PLANT NUTRIENTS PRESENT IN VARIOUS SEWAGE  SLUDGE
	SOURCES, PERCENT  DRY WEIGHT	


Constituent             Illinois-24 cities (7)       7  States  in the U.S.  (8)

Total N
Ammonia Nitrogen
P
K
Range
2.6-9.8
0.1-6.1
0.7-4.9
—
Mean
5.4
1.8
2.4
—
Range
.03
.0005
.04
.008
- 17,6
- 6.7
- 6.1
- 1.9
Mean
3.2
0.7
1.8
0.3

-------
Illinois, while Sommers et a]_.  (8) collected samples from plants in Wisconsin,-
Minnesota, Michigan, Ohio, New Jersey and New Hampshire.  Sommers et  &]_.  (8)
collected over 180 samples for the N, P,  and K data given in Table 1.  As can be
seen, municipal sludge  is  a good source  of N,  P,  and K, the major plant  nu-
trients.  The data collected by both Zenz^t jil_.  (7)  and Sommers jit ^1_.  (8)  was
for a variety of sludges from various  wastewater and sludge treatment processes..
In general, municipal sludges havea total Ncontent pf_l%. to 6% .which is partly
in the  inorganic form arid partly in the organic form (9, 10).  Generally, 30% to
60% of  the total nitrogen in anaerobically digested sludge is present as  ammonia
nitrogen while the remainder is organic  nitrogen (11).  Phosphorus in  sewage
sludge, as shown by the data of Zenz and Sommers ranges from about 1% to 6%.  The
P in sewage sludge is generally considered to be  as available to plants  as the  P
in chemical fertilizers  (12).  Potassium, as shown  in the data  from Sommers,
ranges from about 0.04% to 6.1%, but the mean is 1.8%. Because of the low levels of
K in municipal  sludge,  it is  generally not considered  a good  source  of this
nutrient.       ,
                I

Plant Nutrient Levels in  Various Sludges
    As noted above, the data of Sommers and Zenz represented "a "broad "spectrlim"'
of various wastewater and sludge treatment processes.   As  such,  the data  show
the national picture of  the nutrient content of municipal sludge.  However, the
nutrient content will vary with the types of sludges which  are produced by the
various sewage and sludge treatment processes.  Although limited data are avail-
able, they are sufficient to indicate the relative levels of the plant nutrients
available.

    Sommers (13) reported data on the N, P, and K levels of sludges from POTW's
using anaerobic digestion and aerobic  digestion.  These levels are given  in
Table 2.   As would be expected, the mode of digestion makes little difference in
the total levels of N, P and  K, though  the  chemical state  of  the nutrients  do
vary.

   TABLE  2.   N,  P, AND K LEVELS  IN  ANAEROBIC AND AEROBIC DIGESTED SLUDGES

                                              Type  of  sludge
Nutrient (%)
N
P
K
Anaerobic
4.2 ;
3.0 '
0.3 ;
Aerobic
4.8
2.7
0.4
    Sommers et _al_. (14) also studied the effect of the wet air oxidation (WAO)
process on sewage sludge composition.  Data were compiled on the plants  before
and after treatment.  The data are presented in Table 3.  As can be seen, the WAO-

-------
process significantly reduced  the  soluble and particulate N.  This would  be
expected since ammonia nitrogen is sensitive  to heat  and  will volatilize.

             TABLE 3.   NUTRIENT CONTENT OF SEWAGE  SLUDGE BEFORE
                       AND AFTER WET AIR  OXIDATION  (14)
Constituent (%)
Soluble P
Particulate P
Soluble Total N
Soluble Organic N
Particulate Total N
Particulate Organic N ! 	
Before
WAO
0.082
1.07
1.35
0.293
2.12
1.83
After
WAO
0.004
1.21
0.47
0.173
0.85
- 0.86
    Lagoon ing of sludge also reduces the N content due to  ammonia  volatiliza-
tion and supernatant drawoff.   Peterson et al.  (15) compared the total N  of
fresh digested sludge with that of sludge from lagoons having supernatant draw-
off.  The data are given  in Table 4.

      TABLE 4.  IMPACT OF LAGOONING ON  THE NITROGEN CONTENT  OF  SLUDGE

Constituent (%).	Digested sludge	Lagooned

Total N                                  7.27                         2.60

Ammonia Nitrogen	3.26	1.20


    Heat drying will also cause  a decrease in sludge  ammonia nitrogen  due  to
volatilization.  Peterson ert a.l_.  (15) compared the level of total N and ammonia
nitrogen in sludge before and after heat  drying.  The data are given in Table  5.
Although total N remained unchanged,  virtually all  of the ammonia nitrogen was
volatilized by the heat drying  process.

     TABLE 5.  NITROGEN CONTENT  OF SLUDGE  BEFORE  AND  AFTER HEAT DRYING

Constituent (%)	Before	After

Total N                                    6.7            '               6.4

Ammonia Nitrogen	0.4	trace
                                      8

-------
; '   Primary sludges~"appear""to have "characteristics  similar ""tb"~those  noted
 above  for the  sludges studied by Sommers e_t jil_.  (8).   Manual of Practice No. ~
 8 (MOP)  of the Water Pollution Control Federation (WPCF) gives the values of
 N,  P,  and K for primary sludges  as  shown in Table 6  (16).   Waste-activated
 sludge appears to  have  a somewhat higher N and P  content  than primary sludges.
;This is  expected because activated  sludge  microorganisms  utilize these con-
 stituents  in   significant   quantities.     Anderson   (17)  summarized  waste--
 activated sludge, data from.both the Metropolitan Sanitary.District.of. Greater-
 Chicago  (MSDGC)  and  the Milwaukee Sewage Commission (MSC).  The data are given
 in  Table 7.     :

	TABLE 6.  N, P, AND K  VALUES  FOR PRIMARY SLUDGES	

 Constituent (%)	Range	Typical  value
Total N.
Total P
Total K

1.5 - 4.0
0.35- 1.22
.•.•../-•• 	 0.0 - 0.83

2.5
0.69
... '. . 0.29.

          TABLE 7.   NUTRIENT CONTENT OF TWO WASTE-ACTIVATED SLUDGES

                             Waste-activated Sludge
Constituents (%)
Total N
Total P
Total K
MSDGC
5.6
3.05
0.46
MSC
6.0
1.74
0.34
     There is  not  an extensive amount of data available on the nutrient content
 of  trickling filter  sludge  and what is  available  is rather  old.   However,
 Vesilind (18) reported that  the N and P content of trickling filter sludge was
 2.9% and 1.2%,  respectively.  This would  indicate that the N and P content of
 trickling filter  sludge  is  relatively  low when compared to  that  for waste
 activated sludge.

     Dewatering of sludges can  result in changes in  the  nutrient content of
 sludges.  This occurs due to the removal of soluble components in the super-
 natant,  principally  ammonia nitrogen,  and in the  case  of vacuum filtration
 using lime, by volatilization  of ammonia gas.  However,  it  is difficult to
 generalize about the  exact effect in any particular case.  Zenz et al_. (19)
 gives data on  the N, P,  and K  content  of dewatered  sludges  from  anaerobic
 idigesters using a centrifuge, a vacuum filter  and belt filter press.  The data
 are given in Table 8.   In general, the P  and K  content for  all  3 units studied
 were similiar.  This  was expected because those nutrients  are not very soluble
 in  digested sludges and should not be affected even  if the relative captures


                                      9

-------
of the  various  dewatering techniques were  somewhat  different.   The  vacuum
filtered sludge  had the lowest N concentration  in its cake.  This was  probably
due to the lime addition  and the resulting  ammonia volatilization.

          TABLE 8.  NUTRIENT CONTENT OF VARIOUS DEWATERED  SLUDGES
Constituent Centrifuge
% 	 "Avg. Range
Total N
Total P
Total K
3.25
1.84
0.19
2.47
0.71
0.15
-4.15
- 3.13
- 0.21
Vacuum filter
Avg.
2.8 ,
1.6
0.12
Range
0.71
1.2
0.7
- 3.13
- 1.7
- 2.3
Belt filter press
Avg.
3.1
1.6
0.21
Range
2.2
1.2
0.14
- 3.8
- 1.7
- 34
Value of the Nutrients in Municipal Sewage Sludge

	 It is obvious from the above that municipal sewage sludge has significant
levels of N, P, and K which can be used for fertilizing crops.  In this  section
the amounts of N, P, and K contained in sewage sludge equivalent to  that  in
chemical fertilizers are  computed  and cost estimates for the sludge nutrients
are made based on current fertilier market prices for the  nutrients.  Costs
for N, P,  and  K  were  obtained from the  International  Mineral and Chemical
Company  (20) as posted for January 21, 1980.  The prices of  inorganic N,  P,
and  K  were  $0.253/Kg  ($0.115/lb),  $1.37/Kg  ($0.621/lb),   and  $0.259/Kg
($0.1176/lb), respectively.

    As previously discussed, Sommers et al.  (8) found that the mean N, P, and
K in seven states of the  U.S.  was  3.2^7" 1.8% and 0.3%, respectively.  It was
also noted that a good estimate of U.S. sludge production for the years 1970
and  1985  is  9,843 DMT/d  (10,850 DT/d)  and  16,012  DMT/d  (17,650  DT/d),
respectively.  Using these data and costs for chemical fertilizer  (20), Table
9 was constructed.   The figures given are for daily sludge production. As can

TABLE 9.   DAILY VALUE AND COSTS*  OF NUTRIENTS CONTAINED  IN MUNICIPAL SLUDGE


Year
1970
1985
MT
of
N/d
315
512
Cost of
N
($/d)
79,695
129,536
MT
of
P/d
177
288
Cost of
P
($/d)
242,490
394,560
MT
of
K/d
29
48
Cost of
K
($/d)
7,511
12,432
* Cost figures were derived  using equivalent commercial fertilizer  nutrient
  values.

be seen, the total  daily sludge production in the U.S., based on 1980  dollars,
has a  chemical fertilizer  equivalent market value of $537,000 for  the  year


                                    10    	

-------
1985.  Of course, municipal  sewage  sludge has benefits other than  its nutrient
value.  The organic matter present, for example, offers many benefits includ-
ing improvement in tilth and water  holding capacity for sandy soils.  However,
it is difficult to place a dollar  value on sludge benefits other than its N,
P, and K value.

ENERGY REQUIREMENTS

Energy Required To Produce Nitrogen, Phosphorus and Potassium

    The  production of  nearly all  inorganic nitrogen  fertilizers  requires
energy.  To produce inorganic N, N  is  combined with hydrogen under high tem-
peratures and pressures.  The initial  product is anhydrous ammonia which can
be used directly or converted to other forms of  N  such as ammonium nitrate.
Most  of  the  hydrogen  is obtained  from natural  gas,  although other possible
sources are oil and coal.  Obviously energy  is also required for heat and to
operate the equipment used  in the  manufacturing process.

 «  The production of 0.9 MT  (1 ton) of ammonia usually,requires about 1,080
MJ (38,140 ft3)  of  natural gas of which 630 MJ (22,248 ftj) is used as a source
of hydrogen  and the remainder as  a source  of heat  in the process (21).  In
addition, 34  1  (9 gal)  of  fuel oil  and  54 KW  (72  hp)  oi electricity are
usually used (21).  The  total energy requirement is 47.41x10  kJ/MT (10.27x10
Kcal/ton) of ammonia produced or 47,368 kJ/Kg (5,138 Kcals/lb) of N produced
(21).  The  conversion of ammonia  to other  nitrogen  products requires addi-
tional energy.

    As noted in Table 9, the  daily amount of  N available  in municipal sewage
sludge was estimated to be 315 metric tons (347 tons) for  1970 and 512 metric
tons  (564 tons) for 1985.  This information, coupled  with the fact that 3.8  1
(1 gal) of No. 4 fuel oil contains 152,408  kJ (144,452 Btu's) of energy and
that  the January,  1980 cost (22) of this  fuel  oil  was about $0.24/liter
($0.91/gal), was used to generate  the  data given in Table 10.  The estimates
for the year 1985 were made  using the current fuel costs, since fuel costs are
too dynamic to estimate what they  would be in 1985.

           .TABLE 10.  COMPARISONS  OF ENERGY  REQUIREMENTS  FOR THE
                      PRODUCTION OF INORGANIC NITROGEN





Year
1970
1985
N in
muni-
cipal
sludge

(MT/d)
315
512
Energy to
produce
equivalent
ammonia nitrogen

(KJ/d)
14.9 x 109
24.3 x 109
Quantity
of No. 4
fuel oil
to produce
ammonia nitrogen
0/d)
371,503
605,873
Cost of
fuel




S/MT of N
283.05
284.00 .
No. 4
oil




$/d
89,161
145,410
                                      11

-------
    Unlike N, P  is  not manufactured but is mined from deposits of naturally
occuring rock phosphate.  Therefore, there  is no energy per se required to
produce it except for the considerable  energy required for mining and refin-
ing.  The Mining Congress Journal reported that  the  total energy required to
produce 0.91 MT  (1  ton)  of  elemental P is 182x10°  kJ (172xl(r Btu's)  (23).
With this information and the data on concentrations of P  in municipal sludge
given in Table 9, the  data  shown  in Table 11 were compiled.

         ''  TABLE 11.   COMPARISONS  OF ENERGY REQUIREMENTS FOR THE
                       PRODUCTION  OF INORGANIC PHOSPHORUS
Year
1970
1985
P in
municipal
sludge
(MT/d)
177
288
Energy to
produce
equivalent P
(KJ/d)
35.4 x 109
57.6 x 109
Quantity of
No. 4 fuel
oil to pro-
duce P
(1/d)
882,631
1,436,145
Cost of
fuel
$/MT of P
1,197
1,197
No. 4
oil
$/iI
211,831
344,675
    Potassium  is mined  from  naturally  occuring potash  deposits.    Energy
figures  for the mining  and refining of K^O  were  not available.  However,
Heichel  (24) reported that the "energy required for  potash production  is 40%
to 60%  of the  retail value of K^O".  Therefore, although exact  values were
not available for K?0 production energy requirements,  approximately half the
retail value of  inorganic K~0 can be assumed to be the cost of energy.  Thus,
the  data given  in  Table lz  were developed  using  50% of  cost  values for
inorganic K given  in Table  9.

            TABLE 12.  COMPARISONS OF  ENERGY REQUIREMENTS  FOR  THE
                      PRODUCTION  OF  INORGANIC POTASSIUM





Year
1970
1985
Metric tons
of K/day




29
48
Total retail
value



($/d)
7,511
12,432
Energy cost




($/d)
3,755
6,216
Equivalent
quantity
of No. 4
fuel oil
required
(1/d)
15,646
25,900
 Energy  Required To Incinerate Municipal  Sewage  Sludge

     Sewage sludge  incineration  has  been practiced  for  many years  and  es-.
 sentially evolved from industrial  technology developed during the 19th cen-
 tury.   It was  an  extremely  attractive alternative during the earlier periods
 of  available  cheap  energy  and minimal  air  pollution  control  requirements.
                                      12

-------
However,  due  to the need  for  expensive air pollution  control  devices,  the
need for  large  quantities  of auxiliary fuel to evaporate excess  water,  and
the national  energy  crisis,  the  future  for  this  sludge  treatment  process is
aleak.

    The objective  of an incineration system is to release  heat from a fuel
(in this  case municipal  sludge)  and to completely destroy  all  the  volatile
elements.	Sewage sludge  is difficult  to combust, because--it  -is not'homo-
genous and it contains large quantities of water.  Although  the  fuel content
of sludge  is  fairly  high,  11,656 to 23,312 kJ/Kg dry solids  (5,016 to 10,032 :
Btu/ Ib dry solids), the water content of most  sludges requires  the  addition
of auxiliary  fuel  to maintain  combustion  (25).

    Olexsey and Farrell  (26) did a  survey of auxiliary  fuel consumption for
seven  cities  using  sludge incineration  in  the United  States with  a total'
capacity of 384 MT/d (423  DT/d).  The  average  auxiliary fuel  consumption of
No. 2 fuel oil was 215  1/MT (51.6 gal/DT).  For this report, this  figure was
rounded to 200  1/MT  (50  gal/ton) for  a  nationwide  average.  For purposes of
comparison, it  was assumed that  all of  the  municipal sludge produced in the
United States.was  incinerated. -  Based on. the national  sludge production as
given previously,  and  converting No.  2  fuel oil to an  equivalent amount of [
No. 4 fuel oil, the  energy requirements and costs for  sludge incineration on
a national basis might  be  as given  in Table 13.

        TABLE  13.   ENERGY REQUIREMENTS AND COSTS FOR TOTAL MUNICIPAL
	    ;     SLUDGE  INCINERATION	

          Total           No.  2 fuel  oil              Equivalent No. 4  fuel
        quantity           requirements                  oil  requirements
        municipal	•	      	••	
         sludge                      '..
       incinerated
         in U.S.
Year      (MT/d)    (KL/d)    ($/MT)      ($/d)       (KL/d)    ($/MT)      $/d

1970      9,843    1,969     48.69    479,256      1,998    48.72    479,551
              j
1985     16,012    3,202     48.67    779,304      3,250    48.71    779,945

*  No. 2 fuel oil  has  a  heating  value of 40,834  kJ/1  (146,500 Btu/gal).     \

SUMMARY       :             -          ;    •'                                   |
                                     I                                        i
    The daily costs  for producing equivalent chemical  fertilizer nutrients-
from sewage sludge can be compared  to the  costs required to  incinerate the '
sludges by comparing the sum of the  values presented  in  Tables 10, 11 and 12
with the  values presented in Table 13.   This  comparison indicates  that the
daily  costs  for  producing  equivalent  chemical fertilizer  nutrients  from
sewage  sludge  are  less   than  that  required  to  incinerate  the  sludges.
Furthermore,  it seems  that  the destruction  of the  sludges is  an  unwise
allocation  of a resource.   The energy  requirements  needed  to produce in-
organic N, P,  and K  and to destroy a source of N,  P, and  K are staggering.  It


                                    13

-------
is imperative that the scientific community seriously consider all  resources
involved  and  that recommendations  for beneficial  resource  allocations  be
made.   Energy is  scarce  and it  is  imperative  that energy conservation  be
paramount  in  the  decison-making process  for  all  new  and  emerging  tech-
nologies.
                                     14

-------
                                 .SECTION 5

             METHODOLOGY FOR SELECTION OF NON-FOOD-CHAIN CROPS
    Food-chain crops  are  defined  as  (1)  tobacco,  (2) crops grown for human
consumption and (3) pasture, forage, and feed grain for animals whose products
are consumed by humans.  Non-food-chain crops are, therefore, those crops that
remain.   Thus NFCC  in  the strictest  sense  are  those  crops that  are not
directly or indirectly consumed by humans.

    This definition overlooks the possibility that at some  time the land may
be used for the cultivation of food-chain crops.   In that event, the same
criteria applicable to food-chain crops with respect to soil  residues may also
apply to NFCC. This definition also disregards the entire concept of the food
web.  Some crops could be grown for NFCC purposes, but due  to uncontrollable
factors could  be  consumed in  part by animals and/or fowl  that may later  be
consumed by man.   For  example, soybeans could  be grown for non-food purposes,
but be consumed in part by foraging deer;  these animals  may then  become food
for man.  However, it  is necessary that information in this  area be developed
for use in  the decision-making process.

    Non-food-chain crops were selected  based on the stated definition.  These
crops were first identified by general category using the Standard Industrial
Classification (SIC) code (27).  The code, however, did not include crops such
as sisal, jute, and hemp.  These were added to this list  of  NFCC because they
clearly met the definition criteria, they require N and P for growth, and they
have a market potential.   New crops that will  have a  market  potential but are
still presently in the research stage  (jojoba, euphorbia,  guayule, and bio-
mass crops, for example)  were added to the list. The  possibility does exist
that these crops could obtain the necessary nutrients and essential elements
from sewage sludge for growth.  A review of this list  showed that  there were
many potential NFCC that  could be cultivated  using sewage sludge  as a source
of nutrients.  Two food crops, cotton and soybeans, were added to list.  These
crops were  included for the following  reasons:  (a)  data  available indicated
that the inedible uses of these  crops  could be  significant  enough  to warrant
further study; and (b) cotton clearly has  a high N demand.  In addition, both
crops respond favorably to commercial fertilization.  The selected crop cate-
gories and  SIC codes  are  given in Table 14.
                                    15

-------
      TABLE  14.   CATEGORIES OF NON-FOOD-CHAIN CROPS SELECTED FOR STUDY


SIC                     SIC
Group no.	Industry no.   	


081                          0811                Timber tracts: Timber tracts
                                                 and tree farms (tree  planta-
                                                 tions)

082                          0821                Forest  nurseries, tree
                                                 seed  gathering, extracting
                                                 and setting

Oil                          0119                Flax, flaxseed farms

018                          0181                Horticulture  specialities:
                                                 Ornamental floriculture
                                                 and nursery products

XXX                          XXXX                Hemp, Jute, Sisal

XXX                          XXXX                Miscellaneous (research
                                                 crops)

                                                   a.   jojoba
                                                   b.   guayule
                                                   c.   euphorbia
                                                   d.   energy biomass  (woods
                                                       and  herbs)

013                         .0131                 Cotton

Oil	0116	Soybeans	


    The  selection of the  most  feasible  NFCC suitable for  cultivation  using
sewage sludge, used for this study, was based on a  developed set of criteria.
Liquid digested  sludge, dewatered sludge and composted sludge are  included in
the term "sewage sludge",  unless otherwise  noted.  The criteria used are given
below.

    1.    Verification  of  crop  as  a non-food-chain  crop.

    2.    High market potential, present  and future.

      3.   Suitability for  sludge application for crop  cultivation.

      4.   Fertilizer  requirements  of the  crop.
                                     16

-------
     5.  Sensitivity to environmental factors:

              Hardy
              Climate tolerance
              pH tolerance
              Tolerance to metals
              Tolerance to other sludge components

     6.  Minerals and metals needed for growth and productivity.

     7.  Additional amendments to sludge required for crop cultivation.

     8.  Crop rotation period and efficiency of crops for utilizing nutrients
         in the sludge.

     9.  Economic  crop  size,  acreage  presently  under  cultivation,  minimum
         amount of sludge needed to support growth.

    10.  Documented research on the crop using sewage sludge for cultivation
         of the crop; availability of data on growth and nutrients.       ~   '

    11.  Proximity  of  the  crop  cultivation centers  to  sludge  generation
         centers.

    12.  Potential of sludge application to produce an imbalance in the eco-
         system.

    13.  Dedication of land to permanent growth of NFCC.

The most important criteria for this study were:

    1.   The crops must not produce edible matter that could easily become  a
         part of man's food chain.

    2.   The crop  must  have a demonstrated  or  a  high  probability of future
         market potential.

    3.   The land used to raise the  crop must  have a high probability of being
         used continuously and exclusively for the production of that crop.

    4.   Data must be available that give the response of the crop to sewage
         sludge, or  sufficient data must be  available  for  similar crops to
         allow  probable  response determination  using data extrapolation  and
         inference.

    Twenty crops were initially studied using  the above criteria. These crops
are given in Table 15.
                                      17

-------
      TABLE  15.   POSSIBLE  NON-FOOD-CHAIN  CROPS  AMENABLE  TO  CULTIVATION
                 USING SEWAGE SLUDGE
Crop category
Representative crops
Timber Tracts
Hardwoods:
Forest Nurseries


Flax, flaxseed farms

Horticulture Specialties




Research Crops
Oil Crops
                                       Softwoods:
Aspen
Sycamore
Oak
Sweetgum
Cottonwood

Pine varieties
Douglas fir
Spruce
Those hardwoods and softwoods capable
of propagation by seedlings.

Flax          :   	

Greenhouse varieties
Shrubs
Sod, turf grasses
Lawn grasses

Jojoba
Guayule
Euphorbia
Energy biomass (wood and herbs)

Cotton
Soybeans
    The list of crops given in Table 15  was then reduced to six crops (or crop
categories) using the selection criteria.  Those six  crops  appeared  to be the
most promising non-food-chain crops.  Of those six crops, three were selected
for an in-depth case  study.
                                      18

-------
                                .^SECTION 6 .

                      NON-FOOD-CHAIN CROPS  AMENABLE TO
                      CULTIVATION USING SEWAGE SLUDGE
DISCUSSION OF POTENTIAL CROPS

Timber Tracts

    Commercial timber consists primarily of pulpwood and sawtimber of various
species.  The principal sawtimber species of the  U.S.  are the Douglas fir  and
the ponderosa pine.  .Based strictly on inherent productivity,  oyer__98%  of  the
forest area  in the  northeast  is  capable of growing useable crops  of "timber,',
and over half of all commercial timber!ands  are.  occupied by eastern hardwood
forest types.   Softwood types make  up  approximately 42%,  western hardwoods
approximately 3%,  and  nonstocked  (cleared) areas  approximately  4%  of  the
commercial timberlands.  Approximately 202 x 10  ha  (500 mil acres) of  land in
the U.S. are devoted to commercial  timber tracts, with 40.5 x 10   ha (100  mil
acres) being located in the National Forests (28).

    Sewage  sludge  could be useful  as  a  source  of nutrients  and as  a soil
conditioner in situations where:

    1.   The establishment of tree plantations is desired.

    2.   The reforestation of clear-cut areas or  forest  fire devastated areas
         is desired.

    3.   The production of seedlings  is  desired.

    Tree plantations for  commercial  use are for the most part monocultures,
and   thus   could    possibly   serve   as   buffers    to   the   movement   of
sludge contaminants  into  the  surrounding ecosystems  and  food webs.    "Mono-
cultures",  the  growth  of one species  of plants  to the exclusion  of others,
provide very little  variation of  habitat or food as  is required  for healthy
(balanced) ecosystems.  Therefore, the  utilization  of these monocultures  for
food by "wild" populations of animals or  fowl  may be  restricted  resulting in
little  effect  upon  surrounding  ecosystems.   These  plantations  tend  to  be
located in areas that  are  accessible"by truck  or pipeline for sludge  trans-
port.  Also, they are  located mainly  in  regions  where production  of the crop
is rapid,  such  as  the southeastern U.S.   Examples of tree  crops grown  in
plantations are the  pine, spruce and fir trees for the production of pulp  and
paper and for Christmas trees.
                                     19

-------
    Tree crops used for pulp and paper are normally fertilized only once at
the time of  planting,  and have a  rotation  period of 10 to  20  years.   The
faster growing varieties with a rotation  period of less than 20 years require
intensive cultivation and are not  currently being used to any great extent by
industry because of growing costs.   It  is not a common practice to  fertilize
Christmas trees  since  fertilization causes  rapid growth and  "leggy" trees.
Labor costs  for pruning  would outweigh benefits of quicker growth to saleable
size.

    The nutrient requirements of forest trees  are less well known  than those
of agricultural  crops.   Forests are usually  fertilized naturally, but the
external addition of nutrients and moisture can stimulate tree growth.  The
external addition of nutrients and moisture  could be economically  beneficial
where poor soils exist.  Generally, tree fertilization  has been confined to
nurseries and  orchards.  The cost  of fertilizing  a forest could be expensive
and difficult to  achieve due to inaccessibility of the sites;  however, ferti-
lization by  air  is  feasible.   (Of course, this practice would preclude the
possibility of using sewage effluent or  sewage sludge.)  It has been suggested
that a forest  be fertilized about once every five years, thereby  increasing
yields by as much as 20% (29).  It  is not known  if this increased  volume of
timber would justify the cost.  This would have to be determined on a case-by-
case basis.   Fertilization of forests  is  presently being practiced in Sweden
and France.   Finland  plans  to fertilize over 405,000 ha (one mil  acres) to
increase yields  (29).  A forest in  France is  used as  the  site for the land
application  of wastewater and sludge.  The operation is quite successful in
terms of wastewater renovation and  tree  growth.

Hardwoods--

    Forest timber tracts—Table 16 lists the hardwoods grown  in the U.S.  The
annual nutrient  uptake  of  hardwood forests  is very  low when compared with
agronomic crops.   Table 17 gives the N,  P, and K requirements for tree crops.
It is interesting to note that most  of the N  taken up  by  the tree  is returned
to the soil  during  leaf fall.  Hardwoods are not  suitable for cultivation in
management-intensive  situations  if the  wood  is  to be  used   for  sawtimber.
Also, hardwood forests  tend to be  remote and accessibility  to many of the
sites is difficult.
                                     20

-------
          TABLE 16.   TYPES AND DISTRIBUTION OF  DECIDUOUS TREES (HARDWOODS) IN THE UNITED STATES
           Type of tree
                             Range
                                       Major uses and
                                       growth factors
     1.
     2.
ro
     3.
Eastern Cottonwood
(Populus deltoides)
Plains Cottonwood
(Populus sargentii)
Tulip Poplar or Yellow
  Poplar
(Liriodendron tulipifera)
New Hampshire to New York, central
Michigan, Wisconsin, central  =
Minnesota south and west to North
Dakota, western Kansas, western
Oklahoma and central and south-
eastern Texas and east to north-
western Florida and Georgia.

Montana, Wyoming, eastern Colorado,
northeastern New Mexico, and north-
western and northern Texas and
north to western Oklahoma, Kansas,
Nebraska and western South Dakota.

Massachusetts and southern Vermont
to New York and southern Illinois,
southeastern Missouri, eastern
Arkansas and Louisiana and east to
central Florida.              >
Pulp and Paper
Pulp and Paper I
Softwood, rapid^growth.
Reaches pulp size
in 15 years, saw timber
in 40-50 years.:  Lumber
used in furniture
and home construction.
                                               (continued)

-------
     TABLE 16. (continued)

           Type of tree
                             Range
                                       Major uses and
                                       growth factors
     4.
Royal Paulownia or
Princess Tree
(Paulownia tomentosa)
     5.
American Elm
(Ulmus americana)
ro
ro
     6.
Black Ash
(Fraxinus nigra)
Cultivated and naturalized in
eastern U.S. from southern New
York to West Virginia, southern
Indiana, southern Illinois, and
eastern Missouri and south to
southern Texas and northern
Florida.

North Dakota, southeastern Montana,
western Nebraska, western Oklahoma
and central Texas, and east to
Florida.
Maine to northeastern North Dakota,
south to Iowa, Illinois, Indiana,
West Virginia, Maryland and
Delaware.  Also, local in
northern Virginia.
Softwood, uses unknown,
will reach 20 cm to
25 cm (8-10 in)
in diameter in 10
years,seedingnaturally.
Native to China.
Will grow on many
soils but requires
additional water in
dry regions.  Desired
soil pH 6.0-7.0.
Susceptible to dutch
elm disease.  Source
of lumber.

Grows best in a slightly
acid, silt loam soil
and should be grown
only on moist sites.
Desired soil pH 6.0-
7.0.  Source of lumber,
pulp and paper.
                                               (continued)

-------
     TABLE 16.  (continued)

           Type of tree
                             Range
                                       Major uses and
                                       growth factors
     7.
Green Ash
(Fraxinus pennsylvanica)
     8.
White Ash
(Fraxinus americana)
ro
CO
     9.
Ailanthus, Tree-of-Heaven
(Ailanthus altissima)
From Maine to Montana, northeastern
Wyoming, northeastern Colorado and
Kansas to central Texas, and east_ 	
to northwestern Florida and Georgia.
Maine to northern Michigan and
southeastern Minnesota, south ito
eastern Nebraska, eastern Texas
and east to northern Florida.
Cultivated and widely naturalized  .
as a "weed" tree from Massachusetts
to Iowa and Kansas, south to
southern Texas and Florida and
established to a lesser extent in
western U.S. from southern    •
Rocky Mountains to Pacific states.
Grows on relatively
dry sites and is tolerant
of 'alkaline soil.
Desires soil pH;6.0-
7.0.  Wood for tools,
pulp and paper.:
               (
It is moderate to
fast growing and grows
well on many soil
types.  Desired soil
pH 6.0-7.0.  Wood
for tools, pulp; and
paper.         :

A fast growing tree,
most rapidly growing
woody plant in U.S.
Will thrive under
extremely adverse
conditions, growing
as much as 2.44 M/yr
(8 ft/yr).  Annual
sprouts 3.66 M (12
ft) long not uncommon
where tree has been
cut down.   Immune
to dust and smoke
and may grow to a
large size.  Softwood
has some lumber: and
fuel^talue.    :•
                                               (continued)

-------
     TABLE  16.  (continued)

           Type of tree
                             Range
                                       Major uses and
                                       growth factors
    10.     White Oak
           (Quercus phellos)
    11.
Yellow Oak
(Quercus muehlenbergii)
rsj
12.
           Black  Oak
           (Quercus  velutina)
                             Central Maine to Michigan and
                             Minnesota, south to Iowa, eastern
                             Kansas and eastern Texas, and
                             east to northwestern Florida and
                             Georgia.
Vermont and New York, west to
southern Michigan, southern
Wisconsin and southeastern
Nebraska, south to western
Oklahoma, central and eastern
Texas, east to northwestern
Florida and Georgia, and
north in mountains to Maryland
and to western Connecticut.

Southwestern Maine to New York,
Michigan, Wisconsin, southwestern
Minnesota and southeastern
Nebraska, south to eastern Texas,
northwestern Florida and Georgia.
                                                                           A relatively fast
                                                                           growing hardwood which
                                                                           will grow on a variety
                                                                           of soils.  Desired
                                                                           soil pH 5.0-6.0.
                                                                           Sources of lumber.

                                                                           Lumber.
                                                                    Grows at a moderate
                                                                    rate and will grow
                                                                    on a wide range of
                                                                    soils.   Source of
                                                                    lumber.
                                               (continued)

-------
    TABLE 16.  (continued)

          Type of tree
                             Range
                                       Major uses and
                                       growth factors
    13.   Pin Oak
          (Quercus polustris)
    14.-
Post Oak
(Quercus stellata)
ro
01
     15.
Quaking Aspen
(Populus tremuloides)
Massachusetts and southern New'
York to Pennsylvania, southern;
Michigan, northern Illinois,
southeastern Iowa, and eastern
Kansas, south to northeastern  .
Oklahoma, northern Arkansas,   ,
Tennessee and South Carolina.  :

Local in southern New England
from southeastern Masschusetts
to southeastern New York,      :
southeastern Pennsylvania, West
Virginia, Ohio, central Illinois,
and southern Iowa, south to
eastern Kansas, western Oklahoma
and central Texas and east to
northern Florida.              ;
                               i
High mountains of western U.S. !
from Washington south to       j
southern California, Arizona,
New Mexico and sections of     ;
Texas, and north to Colorado,  j
northwestern Nebraska, South
Dakota and Montana, south in
northeastern U.S. from northern
and eastern North Dakota, extreme
South Dakota, Iowa, Illinois,
Ohio, West Virginia, Pennsylvania,
New Jersey and Maine.
                                                                    Grows relatively rapidly
                                                                    for a hardwood on
                                                                    a wide range of soils,
                                                                    but becomes chlorotic
                                                                    on alkaline soil.
                                                                    Source of lumber.
Grows at a moderate
rate on many soil
types.  Source of
lumber.
Wood for tools, pulp
and paper.      :
                                               (continued)

-------
     TABLE 16.  (continued)
           Type of tree
Range
                                                                           Major uses and
                                                                           growth factors
    16.     Pignut Hickory
           (Carya glabra)
ro
    17.     Bitternut Hickory
           (Carya cordiformis)
18.    White Birch
       (Betula alba, popyrifera)
19.    Sugar Maple
       (Acer saccharum)
Southern New Hampshire and
Massachusetts, west to New York,
southern Michigan, Illinois
and northeastern Kansas, south
to southwestern Oklahoma and east
to Arkansas, Mississippi,
northwestern Florida and Georgia.

New Hampshire to New York, Michigan
and Minnesota, south to southeastern
Nebraska and eastern Texas and east
to northwestern Florida and Georgia.

North Dakota, Minnesota and north-
eastern Iowa, and east to northern
Illinois, Michigan, Pennsylvania,
New York and New England.

Northeastern U.S. to 'Minnesota,
south to Iowa, eastern Kansas,
Oklahoma and northeastern Texas,
east to Louisiana and northern
Georgia and north to Virginia
and New Jersey.
                                                                           Grows at a slow to
                                                                           moderate rate and
                                                                           is adaptable to many
                                                                           soils, including
                                                                           dry sites.  Sources
                                                                           of lumber.
                                                                           Lumber.
                                                                               Lumber.
                                                                               Grows moderately fast.
                                                                               Grows best on fertile,
                                                                               well-drained soil.
                                                                               Desires  soil pH 6.0-
                                                                               7.0.
                                               (continued)

-------
     TABLE 16. (continued)
           Type of tree
 Range
 Major uses and i
 growth factors I
 ,,^-. .20, .-.Silver. Maple-	_  ..
    \      (Acer saccharinum)
ro..:c...
     21.   American Beech
           (Fagus grandifolia)
     22. .  Sweetgum
           (liquidambar styraciflua)
                    » ^f
,Maine .to Michigan  and.Minnesota,	.
 south  to southeastern South Dakota,
 eastern Nebraska and eastern '
 Oklahoma,  and  east to Mississippi
 and Georgia.                  ,>.

                              I
 Maine  to northern  Michigan and
 eastern Wisconsin, south  to  J
 southern Illinois, southeastern
 Missouri,  northwestern        |
 Arkansas,  southeastern  Oklahoma,	
 and eastern Texas  and east to i	
 northern Florida.             )

 Connecticut and  southeastern I
 New York,  to Virginia,  West  i
 Virginia,  southern Ohio,
 southern Illinois, south-    |
 eastern Missouri,  Arkansas   i
 and southeastern Oklahoma,   '
 south  to eastern Texas  and   !
 central Florida.              I
                »
.Grows..rapidly .op ..a,.	
 wide range of soils,
 tolerates mild jsoil
 alkalinity.   Desired
 soil pH 6.0-7.0!.
 Sources of lumber.

 Grows at a moderate rate
 on many different
 soils including!
 limestone soil.)
 Desired pH 6.0-7.0.
"Sources "of lumber/"
 Grows  rapidly on moist,
 but well-drained soil.
 Desired soil  pH;6.0-
 7.0.   Lumber, pulp and
 paper.          j
                                               (continued)

-------
    TABLE 16. (continued)

          Type of tree
                             Range
                                       Major uses and
                                       growth factors
    23.
    24.
Black Locust
(Robinia pseudoacocia)
Red Alder
(Alnus rubra)
Native of Appalachian Mountains
from Pennsylvania to northern
Alabama and in Ozark Mountains of
southern Missouri, Arkansas and
eastern Oklahoma.  Extensively
naturalized in eastern half of
United States.

Pacific coast region from Washington
and western Oregon to southern
California.
Grows relatively rapidly
on a variety of soils.
Desired soil pH 6.0-
7.0.  Sources of lumber.
Adds humus and nitrogen
to the soil.  Wood used
for fuel, furniture,
veneers and paper pulp.
ro
oo

-------
         TABLE 17.  NUTRIENT REQUIREMENTS  FOR A CONVENTIONAL  FOREST  AND  NUTRIENT APPLICATION RATES FOR
                    FOREST CROPS
ro

Type of crop DMTE/hectare per year* Rotation
(yrs)
Conventional forest 3.14 - 6.05 30-80
Pulp plantation 12.33 10
Wastewater i rri gated
forest
Biomass tree farm + 18 6
Biomass tree farm + 18 6
Biomass tree farm +18 6
Fertilization
(kg/hectare
per year)
N . P K
66. 9 80
168 90 0
233 98 2 12
112 48 160
117 233 233
244 130
Reference • '
Sopper and
Kardos (30)
Salo, D.J.,
J.F. Henery
R.E., Inman
(31)
Sopper and
Kardos (30)
Inman, Salo,
and McGurk,J.
(32)
Inman, Salo,
and McGurk.J.
(32)
Inman, Salo,
and McGurk.J.
. (32)
                                                      continued

-------
    TABLE 17.  (continued)
CO
o
Type of crop DMTE/hectare per year* Rotation Fertilization Reference
(yrs) (kg/hectare
per year)

Biomass farms
(Hardwoods)
Wisconsin 11
Missouri 16
Georgia 18
Illinois 18
New England . 11
; Washington 22
Biomass farm 11
Wastewater application
i to a forest +
N P K
Inman, Salo,
and McGurk,
J. (32)
6 64.5 12.3 69.3
6 90.3 17.0 97.60
6 103.2 19.6 111.1
6 103.2 19.6 111.1
6 64.5 12.3 69.3
6 129 24.2 139.3
112 - - Zavitkowski
(33)
- : 90-112 - - Environ-
mental
: : Protection
Agency (34)
                                            (continued)

-------
TABLE 17. (continued)
Type of crop
DMTE/hectare per year*
Rotation
  (yrs)
Fertilization
(kg/hectare
                                                                        N
                                                         K
 Reference
Experimental applications
  to a forest

^ottonwood seedlings
                                       112-224  67-112
                                       224
                   168
              224
Kitzmiller
   (35)

Bonner &
Broadfoot
   (36)
  Dry metric ton equivalent/hectare per year  = metric ton/hectare per year.
+ Estimated application of NPK for given productivity by various methods.
$ EPA design rate of wastewater application to forest land.

-------
    Research by Sopper (37) and Kenady  (38) indicates  that  the  introduction
of sewage effluent and sewage sludge alters the forest environments  drasti-
cally.   Sopper reported  that the  understory vegetation  that  was  present
initially had  all  but disappeared  after 10  years  of  land application  of
sewage effluent,  and  was replaced  by more  tolerant species.   Kenady  found
that the  response  of  vegetative  growth to  the added  nutrients was signi-
ficant.   The  increased  vegetative growth  served  as  shelter  and food  for
herbivores and carnivores and  thus their populations increased tremendously.
It also appears that the vegetation that grew well  in  response  to  the  added
nutrients was  not  a preferred source  of food for  the increased  herbivore
population.  As a  consequence,  the animals  girdled the test tree  seedlings
being  studied  by  Kenady  and  caused wholesale mortality  to the  seedlings.
Studies by  Sopper  (37)  and Urie  (39)  have  demonstrated that some hardwood
forest stands respond favorably to liquid and  dewatered sewage sludge appli-
cations and to sewage irrigation  with no signs of phytotoxicity.

    The forest  is  a very delicate  ecosystem,  and environmental control  is
difficult.  It is next to impossible to operate forest timber tracts as  mono-
cultures.   Any introduction of nutrients will  stimulate herbaceous growth
which can serve as  food for  some of the  animals that are a part of  man's food
chain.  Thus, in terms of the definition of  a. non-food-chain crop,  the  usual
forest crops that  could be  classified as non-food-chain crops should not  be
considered.  Only those timber tracts  that can be easily controlled should be
considered for sludge applications.

    The reforestation of clear-cut areas using sewage sludge could present a
problem in  that  it is difficult  to control  competing  vegetation and  her-
bivores  which  could  be  detrimental  to the  desired  tree  crop  (38).    The
external addition  of nutrients will  stimulate the growth of the understory as
well as tree  growth.   Also, many clear-cut areas are  remote, and  the  sites
would have at best intermittent availability for sludge application.  Forest
fire devastated areas could also  present similar  problems.

    Biomass production—Optimum  biomass production for energy  is  dependent
upon rapid establishment  and early utilization of the growing capacity of the
site.  Optimized conditions for nutrients,  water  and tree growing  space will
be required for maximum yield.  It has been estimated that 5.4 to 26.3 DMT of
biomass/ha/yr  (2.4  to  11.7  DT/acre/yr)  can  be obtained from a  close-spaced
(120 cm  x -120 cm) plantation operating on  a rotation  period  of six  years
(40).

    Cottonwood, sweetgum,  hybrid  poplar,  yellow poplar  and sycamore  have
been studied  for  biomass production  using  municipal  wastewater  and  waste
heat (41).   A close-spaced (0.9M  of  growth  space per tree) hybrid poplar
plantation  fertilized with  sewage effluent  yielded  75.9  DMT/ha   (33.9  -
DT/acre)  of biomass after  a  5-year growing  period.   The  control plot  (no
sewage irrigation) yielded  25.8 DMT/ha  (11.5  DT/acre) at the end  of the  5-
year growing period.  Even though the survival rate (57%)  for the  wastewater
irrigated  plot  was much  lower  than the  control  survival  rate (87%),  the
wastewater  irrigated plot resulted in increased viable biomass yields of 93%
over the  viable yields of the control plot.
                                     32

-------
    In another part of the study using both wastewater irrigation and waste.
heat, Sopper reported that after a year of growth, yellow poplar, cottonwood
and hybrid poplar exhibited a greater mean height in plots receiving waste-
water irrigation only.  The sycamore and sweetgum had greater height growth in
areas which were only irrigated or held as controls.

    Another significant point established by  this  work is that the greater"
biomass yields were  obtained on those plots that had  the closest'spacing."" In™
fact  it  was  shown  that for  each  study,  biomass production  was inversely
related to growing space,  even though  the. greatest mortality occurred in the
high density plots.   A possible  cause  for  the  higher mortality  in the waste-
water  irrigated  plots  was  attributed to stimulated  herbaceous vegetative
growth, which provided a more favorable habitat for mice and rabbits.  This
was the  same  reason given by Kenady  for  the  high  seedling  mortality rate
experienced in his work (38).   The very close  tree  spacing will prevent the
passage of sunlight  needed by  the understory for photosynthesis; thus under-
story  growth  is  inhibited.   This  further supports the  idea  of tree mono-
cultures, rather than the use of the open forests.

    Fiber production—A point often discussed  among foresters  is-the-change
in the specific gravity of wood due to tree fertilization.  Einsphar et al.
(42)  reported significantly  lower  specific  gravities for aspens  grown on
irrigated and fertilized plots.  Mitchell (43)  concluded that the growth rate
of hardwoods  increased  in the presence of N  and  that there  was a positive
trend  toward  increasing  specific  gravity  with   increasing   growth  rate.
Saucier and Ike-(44) .found no  change in tissue composition of  sycamore due to
fertilization.   Murphy  et_ al.  (45) reported  positive changes  in  red pine
wood  and  red oak wood  due to sewage effluent irrigation  of these stands.
The wood  fibers  were altered  (specific  gravity increased, percent latewood
increased)  and the utilization  of  these wood fibers as  raw material for
pulp and  paper is enhanced.

    It appears that the increased growth rate due to fertilization alters the
properties of the wood  in  established stands.   An increase in  the specific
gravity  indicates  an increase  in the mass  of fiber  per  unit volume.   The
increased  fiber  content of the  wood  makes  it a more desirable pulpwood.
Mitchell  (43)  found that  red oaks responded  favorably to irrigation using
sewage effluent  at  a rate of  5  cm (2 in) per  week.   The specific gravity,
percent latewood, and cell  dimension changes in the trees were  considered plus
factors in the utility of the wood for pulp.

Softwoods—

    Forest timber tracts—Table  18  lists  the  coniferous  trees  grown in the
U.S.  Softwoods constitute about 42% of the net sawtimber volume on commercial
forestlands, with the Douglas  fir, ponderosa pine, spruces, and eastern white
and red pines being the most important  softwoods.  The Douglas fir constitutes
by far the greatest  timber reserve in the U.S.   The Douglas fir becomes desir-
able  for  its  lumber at  heights  of approximately 30.5  M  (100  ft).   This is
achievable on  good  sites  in fifty years, but this growth usually requires  a
period ranging from 60  to  100 years.  Pulpwood can  be obtained in about 20
years  from softwoods in the southeast.

                                      33

-------
        TABLE 18.  TYPES AND DISTRIBUTION OF CONIFEROUS TREES (SOFTWOODS) IN THE UNITED STATES
Type of tree
            Range
    Major uses and growth factors
1.  Longleaf Pine
    (Pinus palustris)
2.  Shortleaf Pine
    (Pinus echinata)
3.  Loblolly Pine
    (Pinus taeda)
Coastal Plain from southeastern
Virginia to central Florida and
west to eastern Texas.
From northern Florida through
the Gulf States to Texas and
Arkansas and north on the pied-
mont and coastal plain from
Georgia to Virginia and on the
Delaware peninsula.

Eastern Texas and southern
Arkansas to central Florida
and north on the piedmont and
coastal plain through the
Carolina's to tidewater Virginia,
the Delaware peninsula and 'Cape
May, New Jersey.
Lumber, pulp and paper.  Needs adequate
moisture, secondarily concerned with soil
texture or chemical composition.  Where
soil moisture is limiting, its growth is
 inhibited.  Requires good  drainage  for
 best growth and will grow  on  a wide
 range  of  soils.  Desired soil pH 5.5-6.5.

Lumber, pulp and paper.  Closely associ-
ated with  loblolly  pine throughout  most
of the  inland  or upper  portions  of  the
Gulf Coastal  Plain.  Requires well-
drained soils  with  a desired  pH  5.5-6.5.
Lumber, pulp and paper.  Prefers wet
sites, attaining maximum growth on poorly
drained, moisture-holding clays and clay
loams, and often displays its best devel-
opment on the edges of swampy areas.
Will grow on a wide range of soils.  De-
sired  pH 5.5-6.5.
                                               continued

-------
     TABLE 18.   (continued)
     Type of tree
            Range
                                                                    Major uses  and growth factors
tx>
     4.   Slash Pine
         (Pinus caribaea)
         (elliotti)
     5.   Pond Pine
         (Pinus serotina)
6.  Ponderosa Pine
:    (Pinus ponderosa)
Coastal Plain from southeastern
Carolina to central Florida and
southeastern Louisiana.
Coastal Plain from southern New
Jersey and southeastern Virginia,
south to central and northwestern
Florida and Alabama.

Widely distributed, chiefly in
the Rocky Mountains and mountains
of Pacific Coast region from
southwestern North Dakota and
Montana, Washington and Oregon
to southern California, east to
Arizona and Texas, north to New
Mexico, Colorado, western
Nebraska and Black Hills of
South Dakota.
                                                                Lumber,  pulp  and  paper.   Found naturally
                                                                in  the drainage of Coastal  Plain longTeaf
                                                                forests  east  of the Mississippi  River,  in
                                                                the moderately-drained flatwoods of the  ;
                                                                southeast.  Will  grow on  a  wide range of j
                                                                soils.   Desired soil pH 5.5-6.5.  '       \
                                                                 ;                         |               i
                                                                                          i               '.
                                                                Pulp  and paper.                           '•
                                                                    Lumber.
                                                    continued

-------
     TABLE 18.  (continued)
     Type of tree
            Range
Major uses and growth factors
CO
CTV
     7.  Lodgepole Pine
         (Pinus contorta)
     8.  Jack Pine
         (Pinus banksiana)
     9.  White Pine
         (Pinus strobus)
    10.  Douglas Fir
         (Pseudotsuga
          menziesii)
Western United States from
Washington to southern
California and western Nevada
and from Idaho and central
Montana south to Wyoming,
northern Utah and Colorado.

Great Lakes states of
Minnesota, Wisconsin,
Michigan, and locally
plentiful in Maine, north-
ern Illinois, northwestern
Indiana, northern New York,
Vermont and New Hampshire.

Minnesota, northeastern
Iowa, northern Illinois,
northwestern Indiana, Ohio,
Pennsylvania and New Jersey,
and south in the mountains
to western North Carolina,
northern Georgia and Tennessee.

Pacific coast region from
western Washington and Oregon
to central coastal California
and central Nevada.
 Lumber
 Pulp and paper.   Normally occurs  in
 drier sandy  soils.   Over half the volume
 of growing stock  is  found in  Maine
 where it develops best.   Higher soil
 nutrient levels  in that  state are
 responsible.
 Lumber,  pulp  and  paper.   Occupies  sites
 having a wide range  of moisture  and
 nutrients.  It requires  better site
 quality  for optimum  development
 than other  native pines.
 Timber,  reforestation  and ornamental
 Christmas  trees  and  lumber.  Grows
 rapidly.   Does best  on  sandy to silt
 loam  and tolerates alkaline soil.
 Desired  soil  pH  5.0-6.0.
                                                     continued

-------
    TABLE 18.  (continued)
    Type of tree
            Range
                                                                Major uses and growth factors
CO
    11.  Balsam Fir
         (Abies balsamia)
    12.  Englemann Spruce
         (Picea engelmannii)
13.  Blue Spruce'
     (Picea pungens)
    14.  Red Spruce
         (Picea rubens)
Minnesota, Wisconsin, Michigan,
northern Pennsylvania, New York
and New England.

Mountains of western United
States from Washington to
northern California, eastern
and southeastern Nevada, south-
eastern Arizona and southern New
Mexico and north to central
Colorado and central Montana.

Rocky Mountains region in .high
mountains from western Wyoming
and southeastern Idaho south to
Utah, northern and eastern
Arizona, New Mexico and central
Colorado.

Maine south to eastern New York,
northeastern Pennsylvania and
northern New Jersey.  Also, south
in Appalachian Mountains of
western Virginia, western Maryland,
West Virginia, western North
Carolina and eastern Tennessee.
                                                                Lumber and popular Christmas trees.
                                                                Grows best in moist soils.
                                                                Lumber.
                                                                    Lumber.  Grows best on well-drained
                                                                    soils with pH 5.0-6.0.
                                                                Lumber.   Grows best on well-drained
                                                                soils in the highlands withpH  5.0-6.0.
                                                   continued

-------
     TABLE 18.   (continued)


     Type of tree                           Range                       Major  uses  and  growth  factors
     15.   Western  Red Cedar     Pacific Coast region from western       Lumber.
          (Thuja plicata)        Washington  and Oregon to north-
                              .  western California.   Also, east-     ,
                                ward in Rocky Mountains  from
                                eastern Washington,  northern
                                Idaho and western  Montana.
CO

-------
    Trees  for pulp are  quite  frequently produced  in  plantations or mono-
cultures.   Monoculture.operations appear to  be  suitable for sewage  sludge
applications.  Data in the literature indicate that the softwoods  do respond
favorably  to fertilization  using sewage  effluents  and sludge  (45, 46).
Zasoski  et  al.  (46)  found  that  sludge applications of 112 and  224  DMT/ha
(50 and 100 DT/acre) to a Douglas fir forest caused an unidentified toxicity. At
sludge concentrations of 22.4 and  45 DMT/ha (10 and/20 DT/acre), the 10 and 20
year old plots of  Douglas fir showed a  growth  increase.      -		  --	—
    The presence of the nutrients added to the soil by the sewage will  stimu-
late herbaceous growth.  Because this growth may adversely affect tree growth,
cultural treatments may be required  if  the tree  spacing  is too  wide.  Close
tree  spacing  may reduce the  number  of cultural  treatments,  but the close
spacing on  the  other  hand  might restrict  the use of sewage sludge applica-
tions.  Thus, these close  spacing operations maybe more amenable to  sewage
irrigation  rather than sewage  sludge  application.

    Biomass production—Energy farms, as presently being  studied,  consist  of
rapidly growing tree species that are capable of growing by coppicing (sprout-
ing from  stumps).   Conifers,  with the exception of the  redwoods,-do not
coppice,  and  are somewhat slow in establishing  growth;  thus  tree biomass
production has been centered primarily around the hardwood species. However,
the  loblolly  pine does  meet  most  of  the criteria for  candidate biomass
.species.

    Fiber production—-Trees grown for fiber only do not have to meet the  same
requirements as  trees grown for sawtimber.  In fact, when fertilized, these
trees may  produce  more fiber  per  unit volume,  and research  has  shown  that
fertilization of forest  trees tends to produce  a tree with  more desirable
pulpwood properties (43).

    The more conventional  tree plantations operate on a 30 to 80 year rotation
period, but several of the commercial paper industries are experimenting  with
trees that  have a rotation period  of 8 to 15 years.  Plantations that are
operated using these fast rotation periods  are management-intensive and cost-
ly.  However, it appears that these plantations  could benefit  from the addi-
tion  of  sewage  sludge for  the restoration  of   nutrients.    If  close-space
planting  is practiced, weeds  and other herbaceous growths could  be reduced
considerably.  Tree growth rate increases of up  to 100% using  sewage irriga-
tion have been reported (45).  However, whether  the increase in fiber  volume
would be significant enough to offset the cost of the  operation is not known.

Summary—

    A  list  of some of the fast growing tree species and their market  uses
are given below.

1.  Pines (Pinus sp) - native species, pulp size in 15 years, timber in 20-30
    years.  Procedures for cultivation  presently developed..
                                     39

-------
2.  Tulip Poplar (Liriodendron sp) - native spec.ies.  Reaches pulp size in  15
    years, sawtimber in 40-50 years.

3.  Black Locust (Robinia  sp)  -  native.   Pulp and fence-post  size  in  15-20
    years; resprouts after cutting.

4.  Ashes (Fraxinus spp) - native species.  Pulp  size in  20 years; sawtimber
    in 50 years.                                          .

5.  Poplar Hybrids (Populus.spp)  -  softwood, rapid growth.

6.  Empress Tree (Paulawnia tomentosa) - from China.  Wood soft;  uses  unknown;
    will reach 8-10 inches in diameter in  10 years;  seeding naturally.

7.  Tree-of-Heaven (Ailanthus) -  from Asia.  Widely  established  along  road-
    sides and forest edges.  Rapid growth;  root sprouts.  Should  give a crop
    of pulpwood every 15 or 20 years.

    Any of the  hardwoods  and  softwoods  amenable  to plantation growth  or  to
growth under intensive management practices could be  cultivated using sewage
sludge as a  fertilizer.   However, the application of sewage sludge is more
easily achieved on  normally-spaced plantations.   This spacing practice  would
allow a greater proliferation of herbaceous growth, and thus cultural treat-
ments for the control of weed growth would  be required.  On the  other  hand,
closer spacing would tend  to inhibit understory  growth,  but this would also
decrease the ease with which sewage sludge  could be  applied.

    The above  information  does show that  sewage sludge  could be used as  a
source of nutrients for the cultivation of  the following timber  tracts:

    1.   Softwoods  grown   in monoculture  operations   for  the  production  of
         pulpwood and other wood  byproducts.

    2.   Softwoods that reach maturity in  10-20 years.

Forest Nurseries

    The production of tree seedlings using  sewage sludge is very promising.
Forest seedlings are fertilized  and have a  rotation  period of  6  months to  2
years.  The  seedlings are  usually produced  under controlled conditions and,
thus, would  have minimal impacts  on the forest ecosystem or food web.

    Gouin et^ al. (47)  reported that the Norway spruce and white pine  seed-
lings grew well  on composted sewage sludge.   He also found that  an  application
rate of 224 MT/ha (100 tons/acre) was  sufficient  to yield two crops  of decid-
uous seedlings over a  four  and one half year period.   Kenady  (38), working  in
the open forest environment, found  variable response  to  dewatered sludge  by
softwood  seedlings.   He accounted  for  the variation in  response   based  on
seedling acceptability of, or tolerance to,  the sludge and to competing  vege-
tation that  developed on the growing sites.
                                     40

-------
    In  terms  of seedling  response  to dewatered sludge,  Kenady ranked the
Douglas fir  as  the best,  and  the Sitka  spruce, ponderosa pine and western
hemlock as two, three and  four, respectively.

    The Forest Service reports that there are approximately 170 forest tree
nurseries in the U.S.  (48).  These nurseries  are both bareroot and container.
operations.   The  bareroot operations have  approximately  4,050 .ha (10,.007.._
acres) available for production and the container operations add  another 16.2
ha (40 acres)  to this production capacity.  In 1976 over one billion seedlings
were grown for forest and windbarrier plantings.   This  industry is in a prime
position to  utilize sewage sludge as  a  source  of  fertilizer and as a soil
conditioner for the production of crops.

                                                                 8
    Most of the seedlings  produced in Federal nurseries  (1.1  x  10  in 1976)
are planted  on  National Forest  lands.   The seedlings  producedgin forest
industry nurseries are generally planted on company  lands  (396 x 10  seedlings
in 1976),  but some of these seedlings  are distributed to  other private land-
owners (49).  Reforestation projects  annually involve over 700,000 ha (1.73
mil/acres). Special purpose plantings, which include a) recently cutover land,
b) plantings exclusively for Christmas trees, c) plantings for  surface mine
reclamation,  and  d) plantings for  wildlife  purposes, are  included  in the
reforestation projects.   Forest industries (pulp, timber, etc.) alone planted
421,000 ha (1.04 mil acres)in  1976.

    Gouin et aT_. (47)  has shown that  deciduous and  coniferous  seedlings grow
very well Tn  composted  sludge  amended plots.   Their  work supports that of
Berry and  Marx  (50) and it  thus  appears that  the optimum soil application
levels of  the composted  sludge for  the production of  seedlings are in the
range of 112 to 224 MT/ha  (50  to 100  tons/acre).

    Kenady  (31)  studied  the  response  of coniferous  seedlings to  sewage
sludge.  He reported a variable response  among the  seedlings,  and attributed,
the variation to  seedling species,  the  tolerance  of the  seedlings  to the
sludge characteristics,  and to  the competing vegetation that developed on the
planting sites.   Kenady used dewatered sludge application rates  ranging from
10 cm  to  15  cm per year.   The species recommended for planting in sludge,
based on his data, are the Douglas fir, Sitka spruce, ponderosa pine and western
hemlock, in that order.

Summary-

    Forest  seedlings  established in  container  operations or in plantation
style bareroot operations using sewage sludge have  been shown  to be equal to
and even  superior  in quality  and quantity  to  seedlings established using
standard fertilizers.  Sewage  sludge  can replace the nutrients  removed from
the soil when the  seedlings are extracted, and the sludge  can  be  used to keep
the soils  productive and  thus  can be substituted for green manure or peat-
moss.

    The use of sewage sludge for  these crops  would  reduce the  possibility of
food chain health risks considerably -  the crops  produced are inedible and the


                                     41

-------
soil containing many  of the residues of concern is removed with  the  plant.
Thus, the risks  associated  with using the  land  for  other purposes at  some
future time are also minimized.

Flax and Flaxseed
™™   "•-    ' •• 	   — »

    Flax is one of the  twenty principal crops planted  in  the  U.S.  (51).   As
of 1974, 809,400 ha (2  mil  acres) were under cultivation  for  the  production
of this crop.  It  is best adapted to medium loam or clay soils,  but grows  best
in  well-drained  sandy  loam  soils  in temperate  climates.   In  most  areas,
planting of  the  same land  with  flax is  limited  to once  every six years  to
avoid  soil  exhaustion.   If planted  with  greater frequency, heavy  appli-
cations of fertilizer are required.  The usual practice is not to fertilize a
flax crop,  but when it  is  necessary,  N and P are  the nutrients  required.
Crop yields of approximately 1.4 M  (40 bushels)  are obtained  on 0.405 ha  (1
acre).  Nutrient requirements per ha  are  approximately 23 Kg  (50  Ibs) of  N,
11 Kg (25 Ibs) of P as  P205 and  7 Kg  (15  Ibs) of K as K20 (51).

    There are  no  reported  studies  on the  response of  flax  to  cultivation
using sewage  sludge.   However,  soil  that supports wheat, rye and soybeans
will also support flax.   There  are documented  studies by Sopper  and  Kardos
(32) on  wheat and  by  Hinesly (52) on soybeans  that  show that these crops
respond favorably to sewage sludge.   Increased yields were obtained in  each
case and these crops were quite  efficient  in removing the nutrients applied
to the sites in the sludge.  Thus it can be assumed that flax grown under the
same conditions would show  similar  responses.

    Sludge application for flax seed production may be beneficial  in supply-
ing this crop with the relatively high nitrogen requirements.  Studies  on the
growth of flax have  shown that flax grown on soils with a high  N  content  have
a low fiber  content.   However,  the market  for linen  has  declined due to  an
increase in the use  of  polyesters, and because  the  linen industry is  very
labor intensive.  Therefore flax is not usually grown for fiber production  in
the United States.  Flax seed is grown  in  the U.S.  A market  does exist for
linseed oil which is used for the  production of  paints,  varnishes, linoleum
and oil-cloth.

Horticulture  (Environmental) Specialties

    The horticulture specialties show great potential for cultivation using
sewage  sludge.   In fact, the  industry  could  profit from the use  of  sewage
sludge in light of the  increasing  costs of commercial fertilizers.

    Nutrient  requirements  for the  horticulture  specialties,  which include
both NFCC varieties  as  well as food-chain  varieties,  do not  vary for  each
kind of plant  or species, rather only for the  three major classes of plants.
Although vegetables are one of  the three  major plant species, they are not
being considered  in this study.  The  remaining two major  plant  species  are:

    1.   Small Decorative Flowering  Plants

         a.    perennials


                                    42

-------
         b.   bulbs
         c.   annuals

    These plants require twice as much P  and K than N.  Too much N  stimulates
leaf, and hence top growth at the expense of the flowers wanted.   Phosphorus
produces flowers and strong  roots, and K produces strong  stems  and  vigor  in
roots.  The recommended commercial fertilizers  have NPK  ratios  of  5-10-10  or
5-9-7.   Liquid  sewage  sludge has an  approximate NPK  ratio  of 1-1-0, and
composted sewage sludge has  approximately the same NPK ratio as  liquid  sewage
sludge, with nitrogen being  reduced by about two-thirds.

    2.   Wood plants

         a.   trees
         b.   shrubs
         c.   climbers
         d.   hedges

    These plants need more N than  P or K due to more leaves and hence the need
for more chlorophyll.

    Studies by  Kirkham (53, 54)  under greenhouse conditions on tulips and
chrysanthemums  showed  that  these flowers  grew  well when  fertilized  with
liquid sludge as the  only nutrient source.  There were no  significant dif-
ferences in the  growth  and  health of tulips grown with tap water, primary
effluent or  organic  liquid  sludge.    The  tulips grown with dried organic
sludge produced  buds,  but  did  not open by  the  end   of  the experiment (20
days).   She  concluded that  the  tulips  grew  better with  liquid sludge than
dried sludge, and that this could indicate  that more  sludge  could  be applied
on the surface of the soil than could be mixed or injected  into the soil. The
data also indicated that the high  soluble  salt levels in  soils  treated with
organic  sludges  could  be  harmful  to  some salt sensitive  plants such  as the
tulip.  Epstein and Parr (55) also reported that the  excess  soluble  salts  in
potting mixtures using sewage sludge  compost may be a problem.  However, they
suggested that leaching the mixture with  water  could  alleviate  that  problem.
This was also reported by Hinesly (52).

    The chrysanthemums studied by Kirkham (54)  responded most favorably to a
sludge irrigation rate of 50 ml  per pot per week.  An  irrigation rate  of 100
ml/pot/ week produced plant  leaves that  had necrotic  margins.   The  necrosis
was attributed to sludge ponding and  poor aeration in the  media, rather than
to any nutrient deficiency.  The  chrysanthemum plants irrigated weekly with
50 ml of liquid sewage sludge had similar nutrient compositions except for N
and K when  compared with those plants  that were treated with standard amounts
of liquid or  pelletized  inorganic fertilizers.   Nitrogen was higher  and  K
lower in the sludge treated  plants.   However, the lower K concentration did
not reduce yields or cause  any deficiency  symptoms.
                                    43

-------
    The turf grass industry has  the greatest potential for the utilization  of
sewage sludge.  In the State of Maryland, this industry is a rapidly expanding
segment of Maryland's agricultural economy (56).  In recent years, growth  in
the turf grass industry has exceeded overall agricultural  expansion.  As  of
1974, 34,000 ha (85,000 acres)  were under cultivation for  the  production  of
sod.  The sod industry is  estimated today to be a $2 million  industry.  The
cultivation  of  this  crop  using sewage sludge  is  ideal  since the  crop  is
removed and  transported  to another area which  reduces  the accumulation  of
residues at the growing site.

    Sod  needs  a  deep  sandy  loam  soil  with  some  clay  and  silt  to  hold
nutrients.  Sod  is sometimes grown on organic soils (mulches and peats) which
are excellent from the standpoint of growth and ease of cutting  operations.
However, it has  been reported that sod  grown on  organic  soils  has a  tendency
to  be  coarser and  more open,  and  does not  hang  together  as well as sod
produced on sandy loam soils (57).   But  research  conducted by Darrah et  al.
(58) indicated that the best turf growth resulted from  seed bed  preparation
with composted sewage sludge  and maintenance  fertilization with liquid di-
gested  sludge.   They found that the  sod  with the highest shear  strength
resulted from the high sludge treatment after seeding.  Based  on interviews
with sod farmers, it  appears that not enough sewage  sludge is  available.   It
is their opinion that the crops  respond favorably  to fertilization using the
sludge, and that they will use  it as long as they can obtain it.  Grasses  in
general require large amounts of N (59) for  cultivation, and,  thus,  would  be
an  ideal  non-food crop  for sewage sludge applications.   The  grasses can  be
grown for sod, for seed or for  energy  (for  the production of  alcohol).   In
terms of quantities of sewage sludge, most lawns will  require about  8 Kg (17
Ibs^f processed,sewage sludge,  or 23 Kg  (50 Ibs) of liquid sewage sludge per
93 M  (1,000 ft  ) once or twice a year.

    Generally shrubs  and  trees  are  fertilized  between  December and April.
Fertilizer is only  applied once per  year.   Flowering shrubs  and ornamental
trees greater than 7.62 cm (3 in) in diameter require 45  Kg  of N/ha (40  Ibs  of
N/acre),  90  Kg  of P/ha (80  Ibs of  P/acre), and  45 Kg  of  K/ha (40 Ibs  of
K/acre);  foliage shrubs  require 90  Kg  of N/ha  (80  Ibs  of  N/acre),  56 Kg  of
P/ha (50 Ibs of P/acre), and 34  Kg of K/ha (30  Ibs  of K/acre);  and ornamental
trees  with  a diameter  less than  7.62 cm  (3in)  require  only 1/4  the NPK
requirements as trees with diameters greater than 7.62  cm  (3  in) (59).

    Interviews with large  nursery owners in the D.C. area  revealed  some in-
teresting points.  For the  most  part, the usual  practice  is to  fertilize  once
at  the  time of planting and no  more.  Any increase in the  rate of fertiliza-
tion would stimulate new,  uneven growth of the trees  and  shrubs.  This growth
must be cut back to shape  the trees  and shrubs; otherwise  they would become
spindly  or  the  shape distorted and thus  the  tree or  shrub  would be un-
desirable.  Between crops, a cover of rye  seed  is  planted,  allowed to grow  to
one inch  and then plowed  under  to incorporate organic matter  back  into the
soil.  Therefore, it appears that composted sludge would  be  beneficial to this
industry  and Gouin  has shown that composted sludge  makes  a good potting mix
(47).  The compost could also be used as a mulch  to provide the organic matter
and to  hold water.
                                     44

-------
    Thus,  the  horticultural  industry could benefit by using sewage sludge,
but rates  of application  and  the form  in  which  the sludge would  be most
suitable would have to be  determined on  a case-by-case basis.

Cotton and Soybeans

    Cotton and soybeans were included in this study because  these  crops have
many-potential  inedible uses  as  listed in  Table  19.   The oil  extraction
process used for purifying.the oils  rejects  all the impurities,  and the meals
can be used for the production of inedible  products.

    It has been reported that  cotton will not grow well when irrigated with
sewage effluents that  have high boron concentrations  (60).   Boron  is phy-
totoxic to cotton.   This element has the  tendency to remain in the  wastewater
and to move  with the soil-water  system  (61).   It  is  doubtful  that  sewage
sludges  would  be toxic  to cotton  since boron  is  not  concentrated  in the
sludges.

    Because  of  the  high N demand,  the  best crop  yields  are obtained when
cotton is fertilized.  In those areas where  the crop  is not  fertilized, crop
rotation is practiced to prevent soil nutrient exhaustion.  The average  annual
fertilizer requirements  of cotton are 82 Kg/ha (73  Ibs/acre) of N,  60 Kg/ha
(53 Ibs/acre) of P as P205 and 70 Kg/ha  (62  Ibs/acre) of K  as K20 (51).

    Soybeans are not normally  fertilized since the plant has the  ability  to
fix N.  However,  studies by Hinesly  (52)  show that soybean crop yields  can  be
increased by fertilization with sewage sludge.  In that study,  the  soybeans
grown on plots  with 25.0 mm of sludge had elevated metal concentrations in the
tissues, and did  succumb to phosphorus toxicity.   However plants  grown  on the
plots with sludge applications of 6.4  mm and 12.7 mm showed elevated metal
concentrations, but no phytotoxicity was observed.

    Over 28 x 10  ha are devoted  to  raising  cotton  and soybeans in  the U.S.
(51).   The leading  states in cotton  and  soybean production,  as shown  in
Figures 1 and 2,  contribute more than 80% of the sludge generated in  the U.S.
annually.  Based  on the pounds of N, P, and K  applied to cotton and soybeans  in
1973 as shown in Table 20,  the substitution  of sewage sludge (based on  N) for
commercial fertilizers would require an annual utilization of more than  40%  of
the sludge generated.  The actual percentage of sewage sludge that  could  be
used would of course be  considerably lower,  but the  potential is  there.

    Presently, the  edible  usages for  cotton and  soybeans far  outweigh the
inedible usages.  However, one scenario for these crops could be the selection
of one or two states  in  which  these  crops would be  grown  strictly for their
inedible  usages.   The  residues  remaining  after  harvesting and  processing
would be used for energy biomass.  This scenario if implemented could involve
the utilization  of about 15%  to 20%  of the  sludge  generated annually  in the
U.S.
                                     45

-------
   TABLE 19.  NON-FOOD-CHAIN-CROP USES FOR COTTON AND SOYBEANS

                              COTTON
A.   Fiber
     Textiles
B.   Linters
     1.   mattresses
     2.   coarse yarns
     3.   paper
     4.   packing material
                             SOYBEANS
A.   Oil
      1.  High grade industrial enamels
      2.  Varnish
      3.  Alkyd resin paints
      4.  Inks and stains
      5.  Sealing and caulking compounds
      6.  Synthetic rubber
      7.  Drying oils
      8.  Polishes and waxes
      9.  Synthetic organic  detergents
     10.  Toilet preparation  including shampoos
     11.  Cosmetics
     12.  Soap
                             continued

-------
TABLE 19. (continued)

          13.  Lubricants
          14.  Resins and plastics
          15.  Fatty acids (surfactants, esters and scents)
     B.   Meal (Protein)
           1.  Adhesives
           2.  Paper coatings
           3.  Water-thinned paints
           4.  Plastics
     -      5.  Textile fibers
           6.  Fire foam stabilizers
           7.  Printing inks
           8.  Fillers
           9.  Core binders
          10.  Linoleum
          11.  Emulsifying agents
          12.  Paper and textile sizing
          13.  Leather finishes
          14.  Fertilizer
          15.  (Active industrial research for new uses)
                                    47

-------
       "M   '     .u-   i
        f  • V^	;•      •;
tmtor—L    i
•^:--^f~~yf    ~>.^  /
     FIGURE 1. States with  significant cotton production
            (shaded area)
                           48

-------
FIGURE 2.   States with significant soybean production
           Cshaded area)
                                49

-------
  TABLE 20.  KILOGRAMS OF N, P, AND K APPLIED TO COTTON AND SOYBEANS  (51)

                              N                  (P205)            K?0
Item	(Kg/ha/yr)	(Kg/ha/yr)	(Kq/ha/.yr)


Soybeans                     16                    47              62

Cotton                       82                    60        :      70
Hemp, Jute and Sisal

    Hemp, jute and sisal are not major U.S. crops.  The  products  from  these
crops are presently being  imported.  They  are  amenable to cultivation  using
sewage sludge.  The U.S. grew hemp  during World War II when its supplies from
Japan were  cut off,  but  presently it does  not  appear  that  there are  any
economic advantages for the U.S. production of. these  crops.

    The  jojoba,  guayule and euphorbia are plants  that have  potential  eco-
nomic value.   Suitable  strains  of  these crops could  possibly  be  cultivated
using sewage  sludge  as  the source  of nutrients.   However, much research is
needed on the  growth  requirements  of these crops.   It is recommended  that
fertilization of these crops using  sewage sludge be investigated.  This  would
be an excellent use for  the sludge since a valuable resource  would  be used to
produce  valuable  products  that  could reduce the nation's dependancy on  im-
ported products.   The jojoba is presently being studied extensively at  the
University of California,  Riverside Campus.

    The jojoba is a hardy scrub bush which  produces a  seed from which oil  can
be extracted.   The  plant  grows best  in  arid climates.   The  oil is  very
similar  to whale  oil, and could be used as a  substitute.  The guayule bush
grows in the  deserts  of the  United  States.  The bush  produces a latex  which
has the  potential  of  being as versatile  as the latex  produced by  the rubber
tree.    The  euphorbia  plant grows  naturally  in  the  semi-arid  areas  of
California.   The  leaves  produce  a latex which, when mixed  with acetone,
yields an oil  that behaves as crude  petroleum.

MOST PROMISING NON-FOOD-CHAIN CROPS

    For  this  study the most promising  NFCC were selected from the initial
list of 20 crops  using the  stated criteria.  Based on  the above discussion of
each crop  category and by  application  of  the criteria, six  crops (or crop
categories) emerged as best meeting the goals of this  study.   These crops and
categories are given  in Table 21.
                                     50

-------
        TABLE 21.  MOST  PROMISING  NON-FOOD-CHAIN  CROPS  SUITABLE  FOR
	CULTIVATION  USING  SEWAGE  SLUDGE	~_"

Category	Crop  	

Timber Tracts                                Monoculture  timber  tracts
                                             operations using  softwoods

Forest Nurseries                             Hardwood and softwood seedlings

Horticulture Specialties                     Sod

Research Crops                               Energy  biomass  trees

Oil Crops                                    Cotton
	Soybeans	


Discussion of Selection Process

Timber Tracts--

    The feasibility  of using  sewage sludge as  a source  of nutrients  for  the
cultivation of hardwood forests, while possible and  currently  being  studied
by other researchers, was not judged to be acceptable by this study because:

    1.   The optimum growth for hardwoods is  best  achieved in the open forest
         environment and the impacts  of sewage  sludge on the  forest eco-
         system have not  been fully determined.

    2.   The N and P requirements  for hardwoods  are  low  when  compared with
         other crops and  thus this use of sewage sludge  would constitute  a
         disposal technique rather than a nutrient  recovery technique.

    3.   Hardwoods have  a very slow rotation period and the sites tend to be
         remote and  intermittently accessible.

    4.   Hardwood forests in  general  are not  in  close proximity to sludge
         generation  centers.

    On the other hand, softwoods are amenable to cultivation in monocultures
and the impacts of sewage sludge on those environments  would be  negligible.
Monoculture operations  are  accessible and the  sites are  not that far from
sludge  generation  centers.    While the nutrient  requirements  for  softwoods
are low when compared with other crops, the faster rotation periods for some
species  could  justify  the  consideration of sewage  sludge  as  a source  of
nutrients.  However, the  period of application would at  best  be once every
ten years.

    Some  of the  softwoods  do  appear to be amenable to  cultivation using
sewage  sludge  and thus this  crop  was retained as  a crop meriting  further
study.

                                      51

-------
Forest Nurseries—

    The operation of forest nurseries  for the production of forest tree  seed-
lings met all of the  criteria  considered  in this feasibility study.   Thus,
this crop category was retained for further study.

Flax and Flaxseed Farms--

    Even  though this  crop category  scored favorably  during  the  analysis
phase of this study,  it was decided to delete  it from further consideration
because the market for this crop is declining  and the  possibility does  exist
that some of the land used to  raise this  crop  would be  used to grow a food
crop.

Horticulture Specialties--

    This crop category met  essentially all  of the criteria considered,  and
many nurseries and gardeners cultivating crops  that  are  in  this category  are
currently  using sewage  sludge as  a  soil  conditioner  and as a source  of
nutrients.  Thus, this category was retained for further study.

Research Crops—

    A  lot  of interest was  generated  in trying  to  determine  if  any of  the
research crops  selected  were  suitable for cultivation using sewage sludge.
The jojoba, guayule, and euphorbia grow in arid climates presently.  While it
was felt that suitable strains could be developed, there was just  not enough
available data to determine feasibility.  Thus, it is  recommended that  those
researchers  working with  these  crops  investigate  the  potential  of  using
sewage sludge as a  source of nutrients for  the cultivation of the crops.

    The  feasibility  analysis  did  show  that  energy  biomass crops   could
benefit from the use  of sewage sludge as a source of nutrients  and thus they
were retained for further study.

Oil Crops--

    Cotton  and  soybeans are  food-chain  crops and  thus clearly  do not  fit
objectives of this  study.  However, they were  included under  the  category of
oil crops because the oil purification process could  be adjusted  to exclude
any metals that might be present.   This is true for any crop that  is  purified
such as sugar cane  and sugar  beets.   However,  it was felt that  these  crops
should be  studied  because  they met every criterion, except the  definition.
While  there  are many oil  crops  that could utilize  the N and P in sewage
sludge, it was felt that the  inedible uses  of  cotton  and soybeans were just
too "great to be overlooked.  These  crops  are cultivated in areas  very  close
to major sludge generation centers  and  the  rotation periods  are  fast enough
to  allow  major quantities  of  sludge to  be  used.   Thus,  these  crops were
retained for further  study.
                                     52

-------
                                  SECTION  7

                                CASE STUDIES
METHODOLOGY
    Three  NFCC crops were selected for in-depth case studies.  The crops were
 selected based on discussions with EPA and the project data collected.   Each
 case study examines the feasibility (in terms of land requirements and costs) of
 supplying  the necessary N and P to the crop through the application of sewage
 sludge in lieu of commercial fertilizers. The  sludge would serve to replace or
 reduce the application of fertilizer and soil nutrients.  Data on increased crop
 yields are not definitive  and are  therefore not included in the study.

    The feasibility analysis has shown that there are many NFCC that could be
 produced using sludge as a source of N, P, and organic matter.  Basically, any
 crop requiring N and P could be cultivated using sewage sludge  provided that
 there are no materials in the sludge that would be phytotoxic to the crop.  In
 addition, the sludge can also serve as a soil conditioner.  For certain crops, K
 and other minerals might have to  be added as supplements if they are absent in
 the soil.  Also,  depending  on the soil conditions and the crop,  lime might be
 needed to maintain proper soil pH  levels and to  insure immobilization of some of
 the metals that  might  tend  to become  bioavaiTable  to the plant.

    Sewage sludge does not contain materials that could be potentially toxic to
 any of the crops  reviewed  here based  on documented data.  Phosphorus phyto-
 toxicity to some of the crops has been documented, but this situation was easily
 corrected  by leaching  the  soil with  water.

    Because it appears that  sewage sludge could provide the necessary N and P
 for many NFCC, it is  necessary that other factors be taken into  consideration
.before crops are selected for cultivation.  The intent is to derive beneficial
 uses of the sludge and to produce crops that are of benefit and use in the market
 place.  Much of the research and many of the pilot studies on beneficial uses of
 sewage sludge have produced products  that have little or no market potential.
 Consequently, the sludge product has been given away and/or stockpiled and the
 crop produced has been given away or plowed under. Unless markets are available
 or have been identified, all efforts in this area become exercises in futility.

    The crops  selected for  the  case  studies are currently being sold on the
 open market, with the exception of the research crops.  Because these crops are
 being actively marketed and in the case of biomass crops, actively researched,
 the following  information  is available:

    1.    the preferential  climatic condition  for  the crop;

                                    53

-------
    2.    the nutrient requirements of the crop (this information is necessary,
         since beneficial sludge uses are being  analyzed  and not sludge dis-
         posal alternatives).  This information is used for the determination
         of the potential amount of sewage sludge that should be used to supply
         necessary N and/or P requirements;

    3.    the economic  crop  size (i.e., the amount  of  land  presently under
         cultivation),  the land  area  required, and the minimum  size  of a city
         that could generate enough sludge to support crop production.

    If the cost of supplying nutrients to a crop can be reduced by using sewage
sludge rather than commercial products, then this beneficial use of the sludge
should gain in popularity.  Thus, a simple cost/benefit analysis  was  performed
to determine the costs  involved for using sewage  sludge  in this  manner.  Those
costs were then compared to the costs  involved for the use  of commercial pro-
ducts to  supply the crop nutrients.    Benefit,  as  used in the cost/benefit
analysis, is the difference between the wholesale purchase price  of the commer-
cial source of nutrients and the wholesale purchase  price  of the alternative
source of nutrients, in  this case, sewage sludge (the purchase price is assumed
as no cost to the farmer in this study, unless otherwise  noted).   Cost, as used
in the cost/benefit analysis, is defined as the aforementioned wholesale prices
and does include labor and equipment required for land application, but it does
not include the costs for environmental monitoring and the cost of land.

Crops Selected for The Case Studies

    The following crops were selected for case studies:

    1.    Cotton

    2.    Sod

    3.    Energy Biomass Trees

    These crops were selected because sufficient documented information was
available for those crops to quantify the sludge requirements and to estimate
the costs incurred for supplying nutrients.  Other factors such as: (1) uses for
the crops;  (2) markets available for utilization of  the crops; and (3) crop
growth  habits  and constraints have been  discussed in other sections of this
report.  Figures 1,  3 and 4 show the geographical locations of growth for each
of the  crops selected for the case studies.

Acceptability

    There appear to be no significant barriers  to sludge  utilization for the
production of the selected crops in the context presented. These crops would be
excluded from man's food chain and thus, it is  likely that there would be no
adverse  reaction from the general public.

    The  full  scale use  of  sludge for the  production  of these crops would
involve  considerable changes to  current fertilizer  application   practice.
                                    54

-------
FIGURE 3.  States with significant sod production Cshaded area)
                               55

-------

                                                          ..'••
FIGURE 4.  Millions of acres and percentage of land potentially
           available for energy biomass tree production by
           region (assuming the utilization of 10% of the non-
           agricultural land in each region)
                               56

-------
Sludge application equipment tends to differ from that used for chemical fertil-
izers; odors may develop or be present whenever sludge applications occur  and
for a time thereafter;  and on-site  storage  of  the  sludge may  be  required.

    The advantages of  sludge application to NFCC are:

         Solution  to the  "where to  put  it"  question
         Recovery  of P  fertilizer value
         Recovery  of N  fertilizer value
         Recovery  of soil conditioner value
         Elimination of ultimate disposal problem
         Elimination of incineration option
         Reduction of fertilizer use at comparable application costs (depend-
         ing on option  selected)

    The disadvantages may be stated as  listed  below:

    •    Probable  higher costs than commercial  fertilizer for  application
         options other  than truck spreading
    •    Transport requirements and costs from POTW to site may be excessive
    •    Need different application schemes and equipment
    t    Potential "acceptability"  problems by applicators.

    The major advantage to using sewage  sludge for  the production of NFCC is
probably related to the  fact that sites for the land  disposal of sewage sludges
are difficult,  if not impossible, to  find near urban  areas. This difficulty in
finding suitable sites  near  urban  areas occurs because  the sludges  are  not
recognized as a commodity of value by the general public. Thus, no community
wants the disposal site located in  its domain.  However, using the sludges to
produce crops may  tend  to elevate the sludges to a commodity  of  value;  the
disposal sites could become beneficial  land management  options and would be
welcomed by communities  as ways of preserving the country side/open spaces  and
reducing the potential  for  development.   The use of  sewage sludge for NFCC
production may be found to be more acceptable  to the general public and the crop
production sites may be more easily obtained.

    The major disadvantage to the production  of NFCC  using sewage sludge may be
the sludge transport costs.

Determination of Land Requirements  and Costs

    Based on the annual N and P requirements for cotton, sod  and  biomass  and
the N and  P  content of sewage  sludge,  the  annual  sludge  application rates
necessary to satisfy the nutrient requirements of each crop were  calculated.
Given the quantity of  sludge  generated  annually in each state or region of
the United  States  and  the  sludge  application  rates  determined  above,   the
amount of land in  each  region that can  be fertilized  using  all  of the sludge
produced annually in that region was then calculated.  The  costs  of applying
this sludge  to the land by  three  modes  of  application  were then  determined
and compared to the costs of applying commercial fertilizer at rates needed
to satisfy crop nutrient requirements.
                                   57

-------
    Calculations used for determining sludge and fertilizer application rates
and costs of using commercial fertilizer are presented below, followed by a
description of  the  methods that were  used for  calculating costs of sludge
application.

Application of Nitrogen  to Crops —

    Sewage  sludge—The  N content of most  sewage sludges  ranges from 2 to
3.3%(51)  and 2.5%  was assumed  for this  study.    The total  N  in  the
sludge occurs in various forms,  and  about 30%  to 40% of that is the available
N.  The sludge application rates were  determined as given below:

1.  N requirement  for cotton: 45 to  135 kg/ha/yr  (40  to 120 Ib/acre/yr).
    An N value of 79 kg/ha/yr (70 Ib/acre/yr) was assumed

    Sludge  application rate =   	79 kg/ha/vr	 x 1 MT Sludge
                               (0.35}(0.025 kg N/kg Sludge)  1000 kg Sludge

                                 9  DMT/ha/yr .(4 DT/acre/yr)

2.  N requirement for sod: 191 kg/ha/yr (170  Ib/acre/yr)

    Sludge  application rate =	!!Uig/ha/vr	 yl HT Sludge
                                 (0.35)(0.025~  kg N/kg Sludge) 1000 kg Sludge

                                  22 DMT/ha/yr (10 DT/acre/yr)

3.  N requirement for biomass crops: 112 kg/ha/yr (100 Ib/acre/yr)

    Sludge  application rate «        112 kg/ha/.yr	X1 m Sludge	
                                 (0.35)(0.025  kg N/kg sludge) 1000 kg Sludge

                                  13 DMT/ha/yr (6 DT/acre/yr)

    Commercial  fertilizer—Aqueous  ammonia,  containing 30%  NFL,  was  used
as the basic  source  of commercial N.   The fertilizer application rates  were
determined  as given  below (all calculations  are on  a dry  weight  basis):

1.  N requirement for cotton  = 79 kg/ha/yr (70 Ib/acre/yr)

    N in 30% aqueous ammonia  =     0.30 kg NH.> (14/17) x  1000  kg  Fertilizer
                                       1  kg Fertilizer    i  MT fertilizer

                              =         247 kg  N/l MT Fertilizer

    Fertilizer  application
      rate                    =         79  kq/ha/vr
                                       247  kg  N/MT

                                       0.32 MT/ha/yr (0.14 DT/acre/yr)
                                    58

-------
Cost of aqueous ammonia fertilizer:
range
use cost of

Cost of spreading the
  fertilizer
Cost of custom
  application
N requirement for sod
N in 30% aqueous
  ammon i a
Fertilizer application
  rate
Cost of aqueous ammonia
  fertilizer
Cost of spreading
  the fertilizer
Cost of custom
  application
N requirement for
  biomass crops
N in 30% aqueous
  ammon i a
Fertilizer application
  rate
Cost of aqueous ammonia
  fertilizer
Cost of spreading the
  fertilizer
Cost of custom
  application
$188 to $198/MT ($170 to $180/ton)
$198/MT ($180/ton)
$7.41/ha ($3.00/acre)

$198/MT X 0.32 MT/ha/yr + $7.41/ha
 $71/ha ($29/acre)

191 kg/ha/yr

247 kg N/MT Fertilizer

191 kg/ha/yr

247 kg N/MT

 0.77 MT/ha/yr (0.35 DT/acre/yr)


$198/MT ($180/ton)

$7.41/ha ($3.00/acre)

$198/MT X 0.77 MT/ha/yr + $7.41/ha
 $160/ha ($65/acre)


112 kg/ha/yr (100 Ib/acre/yr)

300 kg N/MT Fertilizer

112 kg/ha/yr__

247 kg N/MT
 0.45 MT/ha/yr (0.20 DT/acre/yr)


$198/MT ($!80/ton)

$7.41/ha ($3.00/acre)

$198/MT X 0.45 MT/ha/yr + $7.41/ha
 $97/ha ($39/acre)
                                59

-------
Application of Phosphorus to Crops--

    Sewage  sludge—The  P content of  most  sewage sludge  is  about  the same
as that for N, and 2.5% was used for this study.  The total P in the sludge
occurs in various forms, and about 4.6% of that is availablefor crop utilization.
The sludge application rates for p wc:re determined as given below:

1.  P requirement for cotton: 59 kg/ha/yr (53 Ib/acre/yr)

    Sludge application rate  f	    59 kq/ha/yr	y  1 MT Sludge	
                            (0.46)TO25 kg P/kg Sludge)   A  1000 kg Sludge

                                    5.17 DMT/ha/yr (2.3 DT/acre/yrj

2.  P requirement for sod: 52 kg/ha/yr (46 Ib/acre/yr)

    Sludge application rate          52 kg/ha/yr	 v  1 MT Sludge
                             (0.46)(0.025 kg/ P/kg Sludge)    1000 kg Sludge

                                    4.48 DMT/ha/yr (2 DT/acre/yr)

3.  P requirement for biomass crops: 92 kg/ha/yr  (82 Ib/acre/yr)

    Sludge application rate  =	92 kg/ha/yr	»  1 MT Sludge	
                             (0.46)(0.025) kg P/kg Sludge     IQOO kg Sludge

                                       8 DMT/ha/yr (3.57 DT/acre/yr)

    Commercial fertilizer—Phosphorus  pentoxide containing 40%  P  was used
as the basic source of P for application to crops.  These fertilizer application
rates were determined as  given  below:

1.  P requirement for cotton =  59 kg/ha/yr  (53 Ib/acre/yr)

    P available in fertilizer =    0.40 kg P	x   1QQQ  kg Fertilizer
                                  I kg Fertilizer   *   i MT Fertilizer

                                     400 kg P/MT Fertilizer
    Fertilizer application
      rate                   =       59 kg/ha/yr
                                     400 kg P/MT
                                     0.15 MT/ha/yr (0.07 DT/acre/yr)

    Cost of P205:

    Range                    =   $1,345 to $1,455/MT ($1,220 to $l,320/ton)
    Use cost of $1,455/MT
    Cost of spreading the
      fertilizer             =      $7.41/ha  ($3.00/acre)
    Cost of custom
      application            =      $1,455/MT X 0.15 MT/ha/yr + $7.41/ha
                                     $226/ha  ($91/acre)


                                    60

-------
2.  P requirement for sod
     P available in
      fertilizer
    Fertilizer application
      rate
    Cost of P205

    Cost of spreading the
      fertilizer
    Cost of custom
      application
3.  P requirement for
      biomass crops
    P available in
      fertilizer

    Fertilizer application
      rate
    Cost of P205

    Cost of spreading the
      fertilizer

    Cost of custom
      application
 52 Kj/ha/yr (46 Ib/acre/yr)

 400 kg P/.MT Fertilizer

 52 kg/ha/yr
 400 k~ P/MT

 0.13 MT/ha/yr (0.06 DT/acre/yr)

  31,455/MT


$7.41/ha ($3.00/acre)

$1,455/MT X 0.13 MT/ha/yr + $7.41/ha
 $197/ha ($80/acre)


92 kg/ha/yr (82 Ib/acre/yr)

400 kg P/MT Fertilizer
92 kg/ha/yr
400 kg P/MT"
 0.23 MT/ha/yr (0.10 DT/acre/yr)

S1.455/MT


$7.41/ha ($3.00/acre)
S1.455/MT X 0.23 MT/ha/yr + $7.41/ha
 $342/ha ($133/acre)
Cost Estimates for Sludge Application--

    Cost data used for this study were derived from existing sources  in the
literature.

    Several  conversations  were held with  project  personnel  related to how
original cost estimates were constructed.  The accuracy of  cost estimates for
sludge application is. probably in the range of 50%.  The estimates are probably
high rather than  low.  This is the  case because:

    •    Available cost  data  probably  included  a  number of factors such  as
         management,  legal, site preparation,  engineering,  etc.,  which would
         be lower or  non-existent for small systems.
                                    61

-------
3EG1N
-^ST
OFTEXT
               •    Available data probably included some transport or sludge" product ipjv
                    costs (costs incurred at the POTW).

               Figures 5; 6,  and 7 show the  data  that were used for  calculating  unit;
           sludge application costs.  These [figures  show capital  costs that  have  been:
           updated to late 1979  costs  using 'the  ENR  CCI of 3131, and operation and main-'
           tenance costs that have been updated using  the October 1979 Consumer Price Index-*
              226-;—e-aptta-1-costs—tn~these-figuresHnclude-land-costST—To-arr4ve-at--the
           capital cost values in Tables 22 through 27, land costs,  assumed at $3,706/ha
           ($l,500/acre),' were   deducted from capital  costs  indicated  on Figures  5,
           6 and 7; this difference was then  amortized at 7 1/8% for 5 years.  Operation and^
           maintenance costs  were  read  directly from the figures.  Total  annual costs
           represent  the sum of  the capital costs and the O&M  costs.

           CASE STUDY 1: ; COTTON PRODUCTION     :

           Land Requirements                    j                                       1
                         !                       !                                       I
               The average  annual  nutrient requirements  for  cotton  are  79  kg/ha  (70i
           lbsAaereJ-of N> 59 Icg/ha (53-;bs/acre)-of-P-as-P205 and-ZO k-g/ha C62-1 bs/acre)-pfc
           K as K-0  (51)i.   Liquid  sludge application to cotton  croplands,  in order to:
           satisfy the N', and  P  requirements of  .the  crop,  requires  that the  sludge  be;
           applied at  an average  rate  of  9  DMT/ha/yr  (4  DT/acre/yr)  for N  and  5.17'
           DMT/ha/yr  (2.3 DT/acre/yr)  for P.  The hectares of land needed in each of the;
           cotton producing states to utilize the sludge generated  in  those  states  was;
           determined by'dividing the quantity of sludge generated  in  the  state by the'
           average annual loading rate.   In most;cases, as shown on Tables 22 and 23, the
           amount of  land required to utilize all of  the sludge  produced  in  each state?
           ("Land fertilized") is less than  the land  that is  currently being harvested for:
           cotton in  that; state ("Land harvested").   In Florida, Kentucky and Nevada, the:
           land needed  to utilize all  of  the sludge in each of those states exceds the land:
           currently being harvested for cotton.   In these three states,  then,  only ai
           fraction  of the  sludge  generated could  be used for producing  cotton.   For
           example, in Florida,

           sludge generated = 160,801 DMT/yr  (177,250 DT/yr)
           land under cultivation for cotton

           amount of land area needed if all the
production = 2,873 ha (7,099 acres)       !

  sludge generated in that state was used I
                 = 160,801 DMT/yr
                     9 DMT/ha/yr
                        i
                 = 17,867 ha (44,149 acres)
        I"'
           quantity of sludge that could be used in Florida for cotton production, based on;
           N, = 2,873 haix 9 DMT/ha/yr
              = 25,857 DMT/yr
                                           BOTTOM OF
                                           :MAGE AREA;
                                           OUTSIDE
                                           DiMEiNSiON
                                           FOR TA3LES

           B>A-287 (Gin.)
           (4-76)
                                          PAGE NUM3EH

-------
OROPPED
HEAD;
    100 i-   		-.-.	  —
                                                                          1000
3EGIN
LAST- LINE
OF TEXT »
                              CAPACITY  -  DRY TONS SOLIDS PER DAY
                  ENGINEERING NEWS RECORD:
                    CCI  -  CONSTRUCTION COST INDEX = 3131,  OCTOBER 1979 (1913=100)
                  U.S.. DEPT.  OF COMMERCE:      1
                    CPI  K  CONSUMER PRICE INDEX i* 226,  OCTOBER 1979
                  DRY TONS. (SHORT) x 0.9072 = DRY TONS (METRIC)
— Figure-5.   Costs of  land  application of sludge by  injection
        f   -  I           I
        I•'•:-.  fl 3/8"      «
  BOTTOM OF
  IMAGE AREA
  OUTSIDE
  DIMENSION
  FOR TABLES
>AND ILLUS-
 , TRATIONS
           EPA-287 (Cfn.)
           (4-76)
                                           PAGE NUMBER

-------
                                                                      1000
CNJ
CM
a.
o
«c
z=
Q
a:
bJ
Q-
o
o
             i .•:-;r,i ^Rgnns^s^n.^;;^
                                                                           r-l
                                                                           CO
                                                                           C_3
a;
Q
ce:
UJ
a.
                                                                           o
                                                                           o
<
i—i
D-


3:
•z.

-------
                                                                      1000
CM
CM
II
I—I
Q_
cc.
Q

01
LU
0.
O
O
o3
O





                                                     T*— 1  M.-r	!T1	" ' . r
                                                     	r*T-~-l —• — —	"tr« —
                            IR-TOW-STS


                                                                      10
       10
                 100


CAPACITY - DRY  TONS SOLIDS PER DAY
1000
                                                       00
                                                       I—I
                                                       CO


                                                        II
                                                       >—<

                                                       C_)

                                                       I—
                                                       
-------
              TABLE 22.  COST OF APPLYING  LIQUID  SLUDGE TO PROVIDE NITROGEN FOR COTTON CULTIVATION
Sludge Land Sludge
generated harvested required
1977
State (OMT/Yr)
Ala.
Ariz.
Ark.
Calif.
Fla.*

Ga.
Ky.*

La.
Miss.
Mo.
Nev.*

N.M.
N.C.
Okla.
S.C.
Tenn.
Tex.
Va.
90.500
34,800
20.800
428,503
160,801
(25.761)
137,201
53,293
(4.717)
40,000
54.201
72,000
18.300
(3,992)
21.000
107.701
47.100
79,801
126.801
301,502
94,701
(ha) (DMT/Yr)
169,976 90,500
137,600 34,800
384,470 20,800
453,270 428,503

2,873 25,761
97,129 137,201

526 4,717
226,635 40,000
594,917 54,201
105.224 72.000

445 3,992
25,901 21,000
28,734 107,701
135,576 47,100
64,348 79,801
149,741 126.801
182,117 301,502
242,003 94.701
Sludge application rate: 8.97 OMT/ha/yr(4.
Fertilizer
•Number in
application
bracket is
rate: 0.32 MT/ha/yr
sludge quantity that
Land
fprtili7pd
Injection
Cap.
O&M
(ha) (S/OHT) ($/OMT)
10,093
3,881
2.3?0
47,789

2.873
15.301

526
4,461
6.045
8,030

445
2,342
12.011
5.253
8,900
14,141
33,625
10,561
0 OT/acre/yr)
(0.14 OT/acre/yr)
can be used.
94
111
118
82

118
87

134
108
103
97

139
118
93
105
96
?3
86
94



31
32
32
29

32
31

44
32
32
31

46
32
31
32
31
31
31
31



Total
Surface irrigation
Cap.
O&M
J/DMT t/ha (S/DMT) ($/DMT)
125 1,121
143 1,283
150 1,345
111 996

150 1,346
118 1,058

178 1,597
140 1 ,256
135 1.211
128 1.148

185 1,659
150 1,345
124 1,112
137 1,229
127 1,139
124 1,112
117 1.049
125 1,121



52
58
65
41

63
47

77
58
57
54

80
65
50
58
53
47
42
52



19
23
26
14

25
18

36
23
21
20

37
26
19
22
20
19
15
19



Truck spread
Total Cap.
J/DMT
71
81
91
55

88
65

113
81
78
74

117
91
69
80
73
66
57
71



O&M
$/na ($/OMT) ($/DMT)
637
727
816
493

789
583

1,014
727
700
664

1,049
816
619
718
655
592
511
637



7
11
14
2

13
6

18
9
9
8

22
13
6
9
7
6
2
6



23
23
24
22

23
23

30
23
23
23

31
24
23
23
23
23
23
23



Total
t/DMT
30
34
38
24

36
29

48
32
32
31

53
37
29
42
30
29
25
29



$/ha
269
305
341
215

323
260

431
287
287
278

475
332
260
287
269
260
224
260



Aqueous
Aflwoni a
30< NH3
($/ha)
71
71
71
71

71
71

71
71
71
71

71
71
71
71
71
71
71
71



CT>
CTl

-------
TABLE 23.  COST OF APPLYING LIQUID SLUDGE TO PROVIDE PHOSPHORUS FOR COTTON CULTIVATION
Sludge Land Sludge
generated harvested required
1977
State
Ala.
Ariz.
Ark.
Calif.
Fla.*

Ga.
Ky.*

La.
Miss.
Mo.
Nev.*

N.M.
N.C.
Ok la.
S.C.
Tenn.
Tex.
Va.
(DMT/Yr)
90.500
34,800
20,800
428,503
160,801
(14,813)
137,201
53,293
(2.712)
40,000
54,201
72,000
18,300
(2.295)
21 ,000
107 ,701
47.100
79,801
126,801
301.502
94.701
(ha) (OMT/Yr)
169,976 90,500
T37.600 34,800
384,470 20,800
453,270 428,503

2,873 14,813
97,129 137,201

526 2,712
226,625 40,000
594,917 54,201
105,224 72,000

445 2,295
25,901 21.000
28.734 107,701
135.576 47.100
64,348 79,801
149,741 126,801
182.117 301.502
242,003 94,701
Sludge application rate: 5.17 OMT/ha/yr (2
Fertilizer application rate: 0.15 MT/ha/yr
*Number
in bracket Is
sludge quantity that
Land
fertilized
Injection
Cap.
O&M
(ha) (S/DMT) (S/DMT)
17.553
6.750
4.034
83.110

2,873
26,611

526
7,758
10,512
13,965

445
4,073
20.889
9.135
15,478
24,594
58,441
18,368
.3 DT/acre/yr)
(O.O'/DT/acre/yr)
can be used.
123
163
179
88

189
98

241
156
146
138

275
175
120
153
135
115
93
123


47
48
51
43

51
46

68
48
48
48

69
51
46
48
48
46
44
47


Total
S/DMT
170
211
230
131

240
144

309
204
194
186

344
226
166
201
183
161
137
170


Surface Irrigation
Cap.
O&M
S/ha ($/OMT) ($/DMT)
879
1,091
1,189
677

1.241
744

1,597
1.055
1,003
962

1.778
1,168
858
1,034
946
832
708
879


164
187
191
157

198
164

214
181
178
172

232
191
164
179
171
164
158
164


34
40
43
25

45
32

60
39
37
35

62
43
34
38
35
33
29
34


Truck spread
Total Cap.
O&M
J/DMT {/ha (S/DMT) (S/DMT)
198 1.024
227 1.174
234 1,210
182 941

243 1,256
196 1.013

274 1,417
220 1,137
215 1.111
207 1.070

294 1,520
234 1.210
198 1.024
217 1,122
206 1,065
197 1,018
187 967
198 1,024


19
32
42
7

48
10

68
32
27
21

69
42
15
27
21
13
7
18


25
26
26
25

27
25

39
25
25
25

42
26
25
25
25
25
25
25


Total
$/DMf
44
58
68
32

75
35

107
57
52
46

111
68
40
52
46
38
32
43


S/ha
227
300
352
165

388
181

5535
295
269
238

574
352
207
269
238
196
165
222


P2°5
40X P
(S/ha)
226
226
226
226

226
226

226
226
226
226

226
226
226
226
226
226
226
226



-------
Therefore, 16% of the sludge generated in Florida could be used to supply the N
needed for the total annual cotton production in that state.

    For the  states  of  Kentucky and Nevada, 9% and 22%,  respectively of the
sewage sludge generated in those'states could be used to supply N to all of the
land under cultivation for cotton  production.

    For the rest of the  cotton producing states, the amount of sludge generated
was not enough to supply the necessary N and P for cotton production. If all  of
the sludge generated by each of these states were used to supply N,  the amount
of cotton land that could be  fertilized in each state ranges from 0.6% to 42%
with the majority of the states generating enough sludge to supply less  than 15%
of the cotton lands in each state  with  sufficient N.

    In the case  of sludge utilization  for the  application of  P  to cotton
cropland, again only Florida, Kentucky and  Nevada would fall short in utilizing
all of the sludge generated in their  respective states.   For the rest of the
cotton producing states,  all of the sludge generated by state could be used  to
supply P.  The amount  of cotton land  in each state that  could be  fertilized
using all  of  the sludge generated by state ranges from 0.5% to 73%. The majority
of the states generate enough sludge to supply less than 20% of the cotton  lands
in each state with  sufficient  P.

Cost/Benefit Analysis

    The costs for  applying liquid sludge to provide N and P for cotton cultiva-
tion are given in Tables 22 and 23,  respectively.  Costs were computed for the
injection, surface irrigation  and truck spread modes of application. The  costs
for custom application  of aqueous ammonia and 40% P as PoOc_are a^so given for
cost comparisons.  The  cost of  the sludge is taken as zero Tor this study. The
costs for custom application include the cost of the  fertilizer, the cost  of
shipping to the central outlet and the cost  of application, but not transport  to
the   site.     A  more   detailed   discussion   of   the   types   of  factors
considered is presented  in Section 8.

    The figures in Tables 22 and 23 indicate that  utilizing  sewage sludge  to
provide   for  cotton   cultivation  can   in  some   cases  be   economically
competitive with custom application of commercial phosphorus pentoxide fertil-
izer if the sludge is applied via truck spreading.  Note that this is true only
for the states fertilizing relatively large quantities of land with sewage
sludge.   In  this  case, the economies  of scale associated with larger sludge
projects  (excluding land costs) are such that truck spreading of sludge may  be
an attractive  alternative  for supplying P to  cotton compared to  commercial
fertilizer applications.

    All other modes for the application of liquid sludge to supply N or P  are 3
to 23  times  the  costs for custom  application  for N or  P.    It  should  be
remembered,  however, that when sludge is applied to  provide N or P, the  auto-
matic addition of  P or N could  be an added benefit at no cost to the user. The
additional benefits to be  gained are  as follows:
                                    68

-------
    1.   A reduction in the energy consumed for the production of commercial
         fertilizers as discussed  in Section 4,

    2.   An improvement in the soil due to the soil conditioner attributes  in
         the sludge,

    3.   The reclamation of  spent  or abused  lands  unable  to  produce  quality
         crops without the addition of  soil  ammendments and  other necessary
         soil nutrients, all  of which  are  provided by  the sludge, and

    4.   The beneficial use  of a valuable  resource-sewage sludge.

CASE STUDY 2: SOD PRODUCTION

Land Requirements

    Most lawns require  about  8 kg (17 IbsJ of processed sewage  sludge, or 23 kg
(50 Ibs) of liquid sewage sludge per 93 M  (1,000 ft  ) once or twice a year.  In
order to satisfy the N and P requirements of sod, liquid  sludge must be applied
at  an  average annual  rate  of 22  DMT/ha/yr  (10 DT/acre/yr)  to  supply the
necessary N and 4.48 DMT/ha/yr (2  DT/acre/yr)  to  supply the  necessary  P.

    Again, the quantity of land needed to utilize all of  the sludge produced in
each state was calculated by dividing the sludge generated in each state (Tables
24  and  25) by the  above  sludge application rates  for  sod.   In  Florida  and
Delaware, this land requirement to use all of the sludge to provide nitrogen for
sod is lower than the land currently harvested for  sod;  thus all of the sludge
could be used. The quantity of land that could  be fertilized  (based on nitrogen)
using  all of  the sludge in  each  state amounts to  86% and 62% of the  land
currently under harvest for  sod in Delaware  and Florida,  respectively.

    In  all   other   cases,, the  quantity  of  land  needed to  utilize  all
of  the  sludge  generated  was  found  to exceed  the quantity of  land  being
harvested for sod in each state.  The  amount of land that  can  be fertilized
is thus constrained by the amount of land currently harvested rather than  by
the quantity of sludge  available  for application.   In Tables  24 and  25,  then
(with  the two exceptions  noted above), "Land fertilized"  is  equal  to  "Land
harvested", and "Sludge required"  is determined by multiplying the  quantity
of  land  fertilized  by  the annual  sludge  application rate.   In  most cases,
then, the amount of sludge generated in the sod  producing states is more than
that which can be utilized for producing the  crop.  The amount of sludge that
can be  used  for providing nitrogen for sod  ranges from  4%  to 100% of  the
sludge produced in the respective  states.  To  provide  phosphorus, only 1.4%
to 33% of the sludge produced could be  used.

Cost/Benefit Analysis

    The costs for applying liquid  sludge to  provide N  and  P  for  sod  produc-
tion are given in Tables 24  and 25, respectively.   The methodology  used for
the cotton case  study  is  the same as used here.   As  with cotton, with the
exception of  applying  sludge to  provide P for sod  v.ia truck spreading, the
cost of custom application using  commercial fertilizer for supplying N  and P

                                   69

-------
                TABLE  24.   COST OF  APPLYING LIQUID  SLUDGE TO PROVIDE NITROGEN  FOR  SOD  CULTIVATION
Sludge Land Sludge
generated harvested required
1977
State (DMT/Yr)
Ohio 367,703
' Ind. 160.001
111. 530,704
Mich. 336,702
Wise. 149,901
Minn. 162,001
Iowa 63,701
Miss. 72.001
Nebr. 27.400
Kans. 38,700
Del. 26,900
Ga. 137,201
Fla. 160.801
Tex. 301.502
Ala. 90,500
Conn. 81,900
N.Y. 537,103
N.J. 216,002
Calif. 428,703
Sludge application rate
Fertilizer application

(ha) (
1.416
809
1,619
2.428
1,214
2,104
607
405
486
809
1,416
809
11,736
1,214
526
1,693
971
971
809

DMT/Yr)
31.152
17,798
35,618
53,416
26,708
46.288
13,354
8,910
10,692
17,798
26,900
17.798
160,801
26,708
11,572
37,246
21,362
21,362
17.798
« 22 DMT/ha/yr (9.8
rate * 0.77
MT/ha/yr
Land
fertilized


Cap.
Injection
Surface irrigation
O&M Total
(ha) (S/OMT) (S/OMT) l/UMI
1,416
809
1,619
2.428
1.214
2,104
607
405
486
809
1,223
809
7,309
1,214
526
1,693
971
971
809
DT/acre/yr)
45
45
45
45
45
45
45
45
45
45
45
45
45
45
45
45
45
45
45

15 60
18 63
15 fiO
15 60
16 61
15 60
20 67
21 66
21 66
18 63
16 61
18 63
14 59
17 62
20 65
15 60
17 62
17 62
18 63

Cap.
O&M
$/ha (S/DHT) (S/DMT)
1,320
1,386
1.320
1,320
1,342
1,320
1,474
1,452
1,452
1,386
1,342
1,386
1,298
1,364
1,430
1,320
1,364
1,364
1,386

20
21
19
16
20
17
23
26
26
21
20
21
11
20
25
19
21
21
21

9
11
8
7
10
8
12
14
13
11
10
11
4
10
13
8
10
10
11

Truck spread
Total Cap.
O&M
S/DMT $/ha (S/DHT) (S/DMT)
29
32
27
23
30
25
35
40
39
32
30
32
15
30
38
27
31
31
32

638
704
594
506
660
550
770
880
858
704
660
704
330
660
836
594
682
682
704

11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11
11

20
22
20
19
21
19
23
24
23
22
21
22
19
21
23
20
21
21
22

Total
S/DHT
31
33
31
30
32
30
34
35
34
33
32
33
30
32
34
31
32
32
33

S/ha
682
726
682
660
704
660
748
770
748
726
704
726
660
704
748
682
704
704
726

Aqueous
Ammonia
30X NH,

($/ha)
160
160
160
160
160
160
160
160
. 160
160
160
160
160
160
160
160
160
160
160

(0.34 DT/acre/yr)
O

-------
TABLE 25,  COST OF APPLYING LIQUID SLUDGE TO PROVIDE PHOSPHORUS FOR SOD CULTIVATION
Sludge Land
generated harvested

State
Ohio
Ind.
Ml.
Mich.
Wise.
Minn.
Iowa
Miss.
Nebr.
Kans.
Del.
Ga.
Fla.
Tex.
Ala.
Conn.
N.Y.
N.J.
Calif.
Sludge
1977
(OMT/Yr)
367.703
160.001
530.704
336.702
149,901
162,001
63,701
72,001
27,400
38,700
26,900
137.201
160.801
301,502
90,500
81.900
537.103
216,002
428.703
application rate
Fertilizer application

(ha)
1.416
809
1,619
2.428
1,214
2,104
607
405
486
809
1,376
809
11,736
1,214
526
1.673
971
971
809
= 4.48
rate » C
Sludge
required

(OMT/Yr)
6,349
3,627
7,258
10,886
5,443
9.426
2,719
1,814
2.177
3,624
6.164
3.624
52.577
5,439
2.356
7,501
4,353
4,353
3,627
DMT/ha/yr (2
.13 MT/ha/yr
Land
fertilized

Injection
Cap.
O&M
(ha) (S/DMT) ($/OMT)
1.416
809
1.619
2.428
1.214
2,104
607
405
486
809
1.376
809
11.736
1.214
526
1.673
971
971
809
.0 OT/acre/yr)
185
214
185
175
191
176
216
218
218
214
185
214
125
191
216
185
204
295
214

56
63
55
53
59
53
68
84
73
63
56
63
47
5?
73
55
61
61
63

Total
Surface irrigation
Cap.
O&M
S/OMT $/ha (S/DMT) ($/DMT)
241 1,080
277 1,241
240 1,075
228 1.021
250 1,120
229 1,026
284 1.272
302 1.353
291 1.304
277 1,241
241 1,080
277 1,241
172 771
250 1,120
289 1,295
240 1,075
265 1.187
356 1,595
277 1,241

177
184
177
165
180
165
186
195
195
184
180
184
153
180
190
177
182
213
184

51
55
50
47
S3
48
60
66
62
55
51
55
37
53
62
50
54
54
55

Truck spread
Total Cap. O&M
S/OMT $/ha ($/DMT) (S/DMT)
228 1,021
239 1.071
227 1.017
212 950
233 1,044
213 954
246 1,102
261 1,169
257 1.151
239 1,071
231 1,035
239 1,071
190 8S1
233 1.044
252 1.129
227 1,017
236 1,057
267 1,196
239 1.071

37 31
48 35
37 31
27 29
45 33
30 29
48 40
50 49
48 42
48 35
37 31
48 35
2 25
45 33
48 42
37 30
45 34
81 34
48 35

Total
S/DMT
68
83
68
56
78
59
88
99
90
83
68
83
27
78
90
67
79
115
83

i/ha
305
372
305
251
349
264
394
444
403
372
305
372
121
349
403
300
353
515
372

P2°5
40X P
(S/ha)
197
197
197
197
197
197
197
197
197
197
197
197
197
197
197
197
197
197
197

(O.OfcDT/acre/yr)

-------
is 2 to 9 times cheaper than the costs incurred if sewage sludges were used
to supply the nutrient.   High  costs  are  probably attributable to the small
amounts of land under crop cultivation.  Truck spreading of sludge to provide
phosphorus appears to  be  actually  cheaper than fertilizer application only
in Florida, due to the economy of  scale associated with  applying sludge to
the larger land area  that  can fertilized in this state.   In all other states,
truck  spreading of  sludge to  supply P  is  more  expensive  than utilizing
commercial fertilizers  although the associated costs  are more  competitive
than the other application modes for either nutrient.  The cost of the sludge
was assumed to be  no  cost  to the user.  The additional benefits are the same
as for cotton.

CASE STUDY 3:  BIOMASS PRODUCTION

Land Requirements

    Table  17  gives  the  various fertilizer  and  sewage  sludge  application
rates that have been  used  or  recommended  by many researchers for  the produc-
tion of this crop.   For this study sewage  sludge  application rates of 13.45
DMT/ha/yr (6 DT/acre/yr) for N  and 7.85 DMT/ha/yr (3.5 DT/acre/yr) for P were
used.          ••-•''

    The  land  available for  crop production  was  more than  that needed to
utilize all the sludge  generated in  the biomass producing states.  As shown
in Tables 26 and  27,  all the  sludge  generated  in those regions or states
could  be  used  to  produce  these crops.  The land  area  to be fertilized was
determined by dividing the amount of sludge generated in  the  region or state
by the sludge loading  rates.   For example, for the northeast region,

    annual sludge  generation = 1,556,010  MT/yr

    applicate rate for  N,  = 13.450 MT/ha/yr

Therefore, the  land  area  that could be fertilized using  sewage  sludge, based
on N  is,

          1,556,010 MT/yr  = 115,689  ha
           13.450 MT/ha/yr

Thus,  if  all the sewage sludge generated in the northeast were used to supply
N to the soil  for  biomass  crop  production,  only 10% of the land that could be
dedicated for  this crop would  be involved.

    The hectares of  land  that could be fertilized  in  each  region using all of
the sewage sludge  generated  in those regions for  biomass production ranges
from  0.6% to  22%.   If biomass production were  undertaken  in  the form of
biomass  plantations  (monoculture - operations),  this would  be an excellent
crop  for  production  using sewage sewage.

Cost/Benefit Analysis

    The  costs  for  applying  liquid  sludge to provide N  and P  for  biomass

                                    72

-------
production are given  in Tables 26 and 27, respectively.  Applying  sludge  via
surface irrigation and truck spreading  is shown  in these tables to be  cheaper
than  applying sludge by  injection for  both  nutrients,  although  the  dif-
ference is more pronounced in the case  of  N.   None of the sludge  application
modes  to  provide  nitrogen  are  competitive with applying  commercial  fertil-
izer,  ranging from  1.25  to 13  times  more expensive.   For  phosphorus,   the
values  presented  in Table 27  indicate  that  the costs of sludge  application
via surface irrigation and truck spreading can  in many cases  be cheaper than,
or in the range of> costs for applying  commercial fertilizer.  Again,  this is
the case mainly  in the  regions  fertilizing large  quantities  of land, due to
the  associated economies  of  scale.    This   is  due  also  to  the  high costs
associated with using commercial P  fertilizer.

SUMMARY        :

      For  the three  crops  considered,  the  utilization  of  sewage sludge  to
supply nutrients for  the production of  cotton and biomass crops does  offer a
significant beneficial sludge use option.  However, utilization of sludge for
sod production is  the most feasible at  this  time.  Sod production would  uti-
lize,  conservatively, 5%  to  10% of  the total  sludge generated  in the  sod
producing  states.   This may  represent  a  significant sludge  use  option  and
should  be  pursued to the  fullest  extent possible.   Most  of the  research on
biomass cultivation has not involved the use of  sewage sludge  to provide N and
P and for  soil conditioning.   Research  on the  use of sewage  sludge  (and  even
sewage effluent)  as a substitute for commercial  fertilizers for the production
of this  crop should  be  encouraged  by  the  sponsoring agency  or  institution.
Additionally, because of the fast rotation  periods being  investigated,  the use
of sewage  sludge would offer  additional  benefits  in terms  of its  soil  con-
ditioner values.   While most of the cotton being produced  is  used  in  part for
food chain products, the possibility does exist whereby a portion  of this  crop
could be grown for non-food-chain  purposes only.  This  crop and   the  soil  on
which it is cultivated would respond favorably  to  sewage sludge applications.

      It is evident from the above  case studies  that  all of  the sewage sludge
generated cannot be used for the  production  of  NFCC.   However, based  on  just
the three  crops  presented  here,  at least 20%  of the total   sludge  generated
could be used for those  crops.   That  is  significant.  The  problem  of  more
sludge generated than is required for application raises other concerns such as
the need for  sludge storage facilities and the need for other  beneficial sludge
use options.   These "needs" should be  addressed  if the eventual objective is to
use and to recycle sewage sludge as much as possible.
                                      73

-------
  TABLE  26.   COST  OF  APPLYING  LIQUID  SLUDGE  TO  PROVIDE NITROGEN  FOR  BIOMASS CULTIVATION
 Region


North East
(Md.,N.J.,
  N.Y.)
Mid-Atlantic
(W.Va.,  Va.,
  N.C.Jenn.,
  Ky.)

South East
(S.C.,Ga.,Ala.,
  Fla.)

South Gulf
(La..Miss.,
  Ark.)

South Central
(Tex..0kla.)

Central
(Iowa.,Mo.,

  Ohio)

Great Lakes
(Minn..Wise.,
  Mich.)

Mid-West
(N.O..S.D.,
  Nebr..
  Kans.)

West
(Wash.,0reg.,
  Calif.)
                                                               Injection
                                                                           Surface  irrigation
                                                                                                                            Truck spread
 Sludge       Land       Sludge      Land
generated   harvested   required   fertilized 	
  1977
                                               Cap.    O&M      Total       Cap.    O&M      Total     Cap.    O&M      Total
(DMT/Yr)      (ha)      (DMT/Yr )     (ha>     ($/DMT)  ($/OMT) J/DMT $/ha   ($/OMT) (S/DMT)  I/DMT $/ha (S/DMT)  (S/DMT) J/DMT t/ha
                                                                        Aqueous
                                                                        Ammonia
                                                                          30X NH3

                                                                         ($/ha)
1.536.010    1,173.646     4.639     115.689       60     22    82  1,103      2
                                                                                                    9    121    5      22    27    363
464,103    1,456,940      1,402      34,506      65     23     88   1.184      9      9     18    242   9      23    32    430



468,303    2,063.998      1.414      34.818      64     23     87   1,170      9      9     18    242   9      23    32    430
           115,001    1,416,469       347       8,550      74


           348.602    1.699.763      1.053      25,919      67
                                                      24     98   1.318     18


                                                      23     90   1.211     10
                                                                                   11     29    390   11      24    35    471


                                                                                    9     19    255    9      23    32    430
         1,194,208    1,133.175      3,606      88.789      60     22     82  1,103      4      8     12    161    6      22    28    377
  648,604    1,335,528      1,959      48,224       63



   74,701      242,823       226       5,554       74
23     86  1,157      6



24     98  1,318     20
                                                                                  8     14    188   7      23    30   403
                                                                                            12     32    430   13      24    37    498
600,203     202,353      1,813      44,625      64     23     87   1,170      7      9     16    215    7      23    30    403
                                                                                                                                 97
                                                                                                                                            97
                                                                                                                                            97
                                                                           97
                                                                                                                                            97
                                                                                                                                            97
                                                                                                                                 97
                                                                                                                                            97
Sludge application rate:  13.45 OMT/ha/yr  (6  DT/acre/yr)
Fertilizer  application rate: 0.45 MT/ha/yr (0.20 DT/acre/yr)

-------
                  TABLE  27.   COST  OF APPLYING  LIQUID  SLUDGE TO  PROVIDE  PHOSPHORUS  FOR  BIOMASS  CULTIVATION
en
                                                                               Injection
                                                                                              Surface irrigation
                                                                                                        Truck  spread
          Region
North East
(MC1..N.J..
  N.Y.)

Mid-Atlantic
(W.Va.,  Va..
  N.C.Jenn..
  Ky.)

South East
(S.C..Ga..Ala..
  Fla.)

South Gulf
(La.,Miss..
  Ark.)

South Central
(Tex.,0kla.)

Central
(Iowa.,Mo.,
  Ill.,Ind.,
  Ohio)

Great Lakes
(Minn..Wise.,
  Mich.)

Mid-West
(N.O..S.D.,
  Nebr.,
  Kans.)

West
(Wash.,0reg.,
  Calif.)
  Sludge       Land      Sludge       Land
•generated    harvested   required   fertilized
   1977                                       	—	
                                               Cap.    O&M      Total       Cap.    04M      Total     Cap.    OiM     Total
 (DMT/Yr)      (ha)     (OMT/Yr)      (ha)     (S/DMT)  (S/DMT) J/DMT $7ha"   (J/DMT) ($/DMT) J/DMT J/ha (J/OMT) (J/DMT)  {/DMT t/ha'
                  Sludge  application rate:  7.85 OMT/ha/yr  (3.5 OT/acre/yr)
                  Fertilizer application rate: 0.23 MT/ha/yr  (0.10 DT/acre/yr)
                                                                                                                                                            40* P

                                                                                                                                                            ($/ha)
1.536,010    1.173,646   1.536,010    198.321       43     31     74    581      30    11      41   322   14      23    37    290        342



  464,103    1,456,940    464,103     59,153       64     31     95    746      32    13      45   353   18      24    42    330        342




  468,303    2,063,998    468,303     59,688       64     31     95    746      32    13      45   353   18      24    42    330        342



  115,001    1,416.469    115.001     14.658       81     32    113    887      34    19      53   416   25      24    49    385        342


  348,602    1,699,763    348,602     44.432       64     31     95    746      32    14      46   361   18      24    42    330        342




1,194.208    1.133.175   1.194.208    152.210       49     31     80    628      30    12      42   330   16      23    39    306        342



  648.604    1.335.528    648,604     82,669       62     31     93    730      30    12      42   330   17      24    41    322        342



   74,701      242,823     74,701      9,521       85     33    118    926      35    20      55   432   26      25    51    400        342




  600,203      202,353    600.203     76,500       64     31     95    746      31    13      44   345   17      24    41    322        342

-------
                                  SECTION  8

                                COST  ANALYSIS
BACKGROUND
  •    It  is desirable to compare the cost of the use  of sludge for its nutrient
and soil conditioner values with the cost of commercial  fertilizer.   In making
such  a comparison, however, a number of important factors which are related to
each  (fertilizer  and  sludge)  make comparisons  difficult.

      A straightforward cost comparison approach would  consist of determining
the following:

           Fertilizer                         Sludge

           A.    Cost  of fertilizer           A.  Cost  of  sludge
           B.    Cost  of transportation        B.  Cost  of  transportation
           C.    Cost  of application          C.  Cost  of  application

      In  the case  of fertilizer, the cost of fertilizer  purchased at an outlet
by  a  farmer  includes  the  cost of production, transportation  and profit.   The
farmer  must then transport  the fertilizer to  the  location  of  interest and
.apply it.   Services  are  available  to transport  and  apply fertilizer for
farmers.  For example, the  Southern  States Cooperative will provide such a
service  to the farmer at a cost.  For the purposes of  analysis during  this
study, the current cost of fertilizer  was determined from the  chemical market-^
ing literature  (62),  and  the costs of  transport and  application (custom appli-
cation)  were determined  based on information  from companies  which provide
that  service  and  from the literature  (63).

      In  the case  of sludge, a determination of the cost factors was much  more
complex.  Since  sludge  is not in common  use  for application to crops,  even
NFCC, and is  not  considered to be  a "commodity", it  was difficult to consider
the cost of the sludge as recoverable.  The cost of  sludge, therefore, for any
applications  to NFCC over the near term future should  probably be considered
zero.   This  means  that  the cost  of sludge production  should be totally al-
located  to the  cost of wastewater  handling, treatment and disposal.  There is
a significant cost associated with the production of sludge.  Total costs may
amount to one-half of  the sewage treatment  expenditures on a total annual  cost
basis at a typical  sewage treatment plant.

      It  is difficult,  if not impossible,  to  determine  sludge  handling, de-
watering and  disposal  costs accurately because  of the many different account-
 ing systems which are currently  in use by POTW  operating  authorities.   The

                                     76

-------
cost to the consumer, however,  may be widely different from the cost of actual
production.  The price is often kept low  in  an  attempt  to get rid of excess
quantities.  For example,  the  December  1979  cost of sludge was $4.52 per MT
($4.10/ton) F.O.B.  Chicago (62).  At this price,  even if  the  cost of sludge is
included  in  this  analysis,  it is  a small  percentage of the combined sludge
transport and application cost.

     Also, costs  for various  alternatives for  sludge  handling and disposal
are often presented  in the most favorable light depending on which option is
being promoted.  Even in the cases where  costs  have been assembled and analyzed
with  reasonable diligence,  it  is difficult  to separate  costs  of  sludge
production from the  costs of sludge transport and application  to the land.

     For the purposes of this  study, various  sludge disposal experiences in-
volving application  to the land in the U.S. were analyzed.  Data were avail-
able from Chicago, Los Angeles/Orange County Metropolitan Area (LA/OMA), San
Francisco and elsewhere (64, 65, 66, 67).   It appeared that  the San Francisco
study  had  included  the  results  of previous  studies and  was a  summary in
itself.  It was, therefore, used as a primary reference for this work.

     Based on a review of the  cost data,  it  was difficult to  determine what
had been  included  in capital  costs and  the operating and maintenance costs.
Trucks for transport, for  example, might have  been  included   in the capital
cost or a leasing  assumption  might have  been made.  For any sludge application
venture, site preparation  costs for storage areas and a cost  for the operation
and maintenance of storage facilities  should  be  included.  This was uncertain
in some of the reports.

     It was  also difficult to  determine the  lifetimes of spreading, storage
and sludge moving equipment at  the  site because of a  general  lack of long-term
experience in the U.S.  Lifetimes  used for annualizing costs for such equip-
ment ranged from 5 to 20  years.   Transportation requirements  for  sludge are
fixed  in  that  the  sludge must  be moved  from  generating  points  at sewage
treatment plants to  points of  application which may be long distances away.
Fertilizer sales  operations,  on  the  other  hand,  will normally  be located
centrally for potential use  by the farmers.   Also,  the  costs of  fertilizer
"off the shelf" at the outlet already  include  some transportation costs (pro-
bably by train from  the point  of manufacture  to the point of distribution).

     The  application of sludge  to crops  -  even NFCC  which   require longer
growing periods - is  likely  to be  seasonal.   Weather conditions will be the
most prominent constraint throughout the northern and Plains states.  Changes
may, therefore, be  required  at the POTW  in  order  to  accommodate  the-large
scale application of sludge  to NFCC.   Because of pick-up schedules, storage
facilities may be  required.   Because of  application  techniques  and  equipment,
it may be desirable to produce sludge  with varying water composition  in order
to facilitate application during different times of the year and/or for dif-
ferent crop types.

     There are  other  considerations  which  complicate  the  cost  comparison
picture.   A  farmer  buys commercial fertilizer  on  the basis of NPK content.
Sludge, on the other hand,  will provide  N,  some  P and very little K. The cost


                                    77

-------
of augmenting sludge with additional K was not considered in this study.  The
types of equipment used to apply commercial fertilizer versus that required to
apply sludge may be different for terrain, crop type  and weather conditions.

     In  the  case of application  of sludge to  NFCC,  it may  be possible to
consider the application  of  sludge  to accelerate growth conditions  in cases
where no commercial fertilizer is currently being applied.

     Because of the foregoing considerations  and others,  it  was  not possible,
based on currently  existing  data  and information,  to fully draw comparisons
between current commercial fertilizer costs and expected  costs for sludge ap-
plication.  The determination of  accurate costs for  sludge application alter-
natives is clearly an area for further research and development effort, and if
ventures are to be successful and alternatives made believable,  such further
work should be done in  the near future.

     A cost  comparison has been developed and  the  information  is presented
under various conditions in order to perform  a sensitivity  analysis  and pro-
vide the  reader with  a general  idea of how costs might  vary  depending on
various conditions.            .

DISCUSSION AND SUMMARY

Sludge Application Costs Comparisons

     It must be  emphasized that applying  the sludge  based on the N content
will simultaneously supply the soil  with more P than the crop needs.   For most
crops this will probably not be a problem.  However,  several  crops (soybeans
and possibly the  Douglas  fir)  have  shown a decrease  in  growth   due to phos-
phorus phytotoxicity.  Thus,  the  application  of the  sludge based on P  might be
preferable if phosphorus phytotoxicity is suspected  of being a concern.  The N
requirements for the crop will not  be sufficient, if  sludge  is  applied based
on P.  The N  in  the  soil might be sufficient,  or supplemental N in the form of
commercial fertilizer might have to be added.

     Table 28 summarizes  the  total  annual  cost (O&M  plus annualized capital
cost) for sludge application to the  three selected crops.  The costs  are pre-
sented based on supplying required  quantities of N  and P in each case; costs
for providing the same  quantities of N and P  using  commercial fertilizer are
given for comparison.   These  cost figures do not include the cost of trans-
porting sludge to the site nor the cost of  storage.  Details of  costs derived
during the study are presented in  Tables  22  through 27.  These tables also
give the results by state or region for  each  of the three crops.

     For this feasibility study, the cost values were based  on three  modes of
application  -  injection,  surface  irrigation  and truck-spreading of liquid
sludge.  It was found  that, while some effort  has been made to  determine the
cost of sludge application, most of the  results reported do not  show exactly
what items were  included  in  the  cost values.   The  cost  curves  (Figures 5 to
13) used in this study were based  on a study of sludge application in the San
Francisco Bay Region (65).
                                    78

-------
                     TABLE 28.  COST COMPARISONS FOR SLUDGE AND COMMERCIAL FERTILIZER

Application
Mode
Injection

Surface
Irrigation

Truck
Spreading

Cotton Sod Blomass
Units N(S)1 Fertilizer2 P(S)3 Fertilizer4 N(S)1 Fertilizer2 P(S)3 Fertilizer4 N(S)1 Fertilizer2 P(S)3 Fertilizer4
J/OMT 137
J/ha 1,229
J/DMT 79

J/ha 709
J/DHT 33

J/ha 296
198
71 1
198

71 1
198

71
200 1.455 62 198 2,58 1,455 89 198 95
,034 , 226 1,364 160 1,156 197 1,197 97 746
218 1,455 30 198 234 1,455 19 198 46

,127 226 660 160 1,048 197 255 97 361
56 1,455 32 198 75 1,455 31 198 43

290 226 704 160 336 197 417 97 338
1,455
342
1,455

342
1,455

342
N(S) « Nitrogen supplied using POTM sludge (does not Include cost of sludge).
2 Fertilizer »
Nitrogen supplied using commercial fertilizer (custom application).
3 P(S) • Phosphorus supplied using POTW
4 Fertilizer «
Phosphorus supplied using
* The cost data presented for the sludge
at the site.

sludge (does
commercial
not Include cost of sludge).
fertilizer (custom application).


and the commercial fertilizer do not Include the cost of transportation to the site and the cost of storage



10

-------
     This study considered various regions and states.   The  primary  impact on
regional cost variations is due to the scale  of sludge application.  The Con-
struction Cost Index (CCI) was used to adjust costs given in the literature to
September 1979  (national  average basis).  The maximum  regional cost varia-
tions in the CCI were about 7% for all cities (analysis  conducted using March
1979 data).  Most variations  were  less than  5%.   The regional costs, there-
fore, were not computed using regional CCI values.

     Any application of  sludge  to recover the N  value  involves the coinci-
dental  application  of P  and  K  as well.   Some cost  value  could properly be
claimed for the P  and K recovery, especially  in the case  where NPK values as a
whole are  desired for the crop.   Similarly, when applying sludge for the P
value, there is a  synonymous recovery of N and K.   However,  in both instances,
the coincidental  nutrient application is a  benefit  derived by using sewage
sludge; no cost values  are claimed.  To illustrate the impact on the  cost com-
parison v/hen coincidental nutrient  application is accounted  for, the data on
Table 29 were prepared.   The fertilizer  costs presented include a mixture of
the required quantities of N and P for the crops.  The value of K has not been
included because of the relatively small  sludge K  content.   Table 29  shows the
following:

     1.   For all sludge  application  modes considered,  application  by injec-
          tion  is the  most  expensive with  one  exception.   Application by
          surface irrigation  is more expensive when applying sludge,  based on
          P, to cotton.

     2.   Truck spreading is  the  cheapest application mode  except for apply-
          ing sludge,  based on  N,  to  sod or  biomass.  Application of sludge,
          based on N,  to  sod or biomass is cheaper when  surface irrigation is
          used.   Truck spreading appears to be cost competitive with custom
          application  of  the  commercial  fertilizer mixture.

     3.   Application  of  sludge, based  on N or  P,  to biomass  using surface
          irrigation or truck spreading is cheaper than  custom application of
          a mixture of commercial  N and  P.

Transportation  Costs

     The most significant impact on regional costs variations will clearly be
due to  the transportation costs from  the centers  of  sludge  generation to the
application sites.  Transport costs were considered separately in this study.
Transportation  costs  are  presented in Figures 8  through 13  for 20,  40 and 60
mile distances  and for liquid and  cake shipping options.  In most cases, cost
differences were  apparent among pipeline, barge,  railroad and truck. Figures
11, 12  and  13  show transport costs for  the  cake  option  (pipeline not appli-
cable  to  the transport of  sludge cake).  Trucking  costs  were largely non-
varying for  the full  range of production values.  Trucking  operations, how-
ever,  are convenient  for use  at  small  plants  where  rail  sidings are not
feasible.   As  expected,  there  is  little economy of  scale  in  the case of
trucking  sludge cake.   There  is  little economy of scale for rail transport at
lower sludge quantities and distances.  Rail and barge  transport  become more
cost  efficient  at longer transport distances.  Barge transport  is  of course


                                    30

-------
                                                                                 **
                              TABLE 29.   COST  COMPARISONS  FOR  SLUDGE   VERSUS COMMERCIAL  FERTILIZER
                                             (FERTILIZER COSTS  INCLUDE  BOTH  N AND  P)
00
           Application mode     N(S)
           Injection
           Surfoci?
           • rriiiition
                spread
1.229

  709
  296
                                        Cotton
                                                              Average total annual cost  ($/ha)
                                                                                Sod
            P(S)
            Fertilizer *
              N(S)
            F(S)
            Fertilizer*
               N(S)
1.034
1.127
  290
290

290
290
1.364
  660
  704
1.156

1.048
  336
350

350
350
1.197
  255
  417
           *  All fertiliser costs are for custom application.
           ••  t'r-y weight basis
                                                                                                                        Biomass
            P(S)
746

361
338
                                                                                            Fertilizer
433
432
432

-------
not applicable to inland POTW's or  inland  application  sites.

     Cake  transport  implies a number  of considerations  which affect  total
system costs for NFCC application.   If cake  is  being transported,  dewatering
costs  at  the POTVI  are  probably  higher  than for  other options.   Cake may
require re-slurrying at the application  site for certain  types  of  spreading.

     Unit costs for rail and truck transport  of  liquid  sludge  are similar and
fairly constant  for all ranges  presented.  Pipeline  costs are affected  by
pumping station requirements, but there is a  significant economy of scale for
increased  capacities.   Pipelines,  however,  require  a  fixed commitment over
long periods of time and are  very capital  intensive.   Rail transport  is not
labor  intensive.  Existing rail lines and  facilities can  be used with  little
or no  adverse impact, and trains  have a  very low fuel  consumption  per  metric
ton-kilometer.

     Pipelines and  barges for  liquid sludge  transport and  barges  for  sludge
cake transport are  clearly  more  cost efficient for most ranges of potential
application, but are very  limited by site, right of way,  and  on/off  loading
requirements.

     Over  the  distances analyzed,  the  costs  for  transport  of sludge cake
averaged  327/DMT  ($25/DT)   and  for  liquid  sludge,  the  costs  for  transport
averaged  $110/DMT  ($100/DT)  for  both rail and truck, which are likely to  be
the most common options.  The costs for sludge transport and application could
be increased from two to seven orders of  magnitude over the costs for applica-
tion alone.

     For  the  three  sludge  application  modes  investigated,   the  costs for
applying  the sludge, based on N,  range from  41% less than  the  cost of  custom
application of a commercial fertilizer mixture  to 324% greater  than the cost
of  custom  application.    When  transport costs  are  added  to  the  sludge
application costs, the total cost for the sludge ceases to be cost competitive
with custom application, even for  the-cheaper application modes. For example,
in the case of N application, for biomass production  using surface  irrigation
(Table 29), the cost for sludge application, on a $/ha basis, is 41% less than
the  cost  for custom application  ($/ha)  of  a mixture  of N and P  commercial
fertilizers.  When the transport cost (S/DMT) for sludge cake  is added  to the
application  cost of the sludge,  the cost of the sludge  is increased  by 142%
(see Table  28).   This  142%  increase in  the sludge cost,  on  a $/DMT  basis,
increases  the  sludge cost,  on a $/ha basis, from 41%  less than the cost for
custom jipplication  to 43% greater than  the cost for custom application of a
fertiliser mixture.  This shows that adding transport cost to  the  application
cost  would put most  options considered far out  of  the  range  of  possible
consideration  (based  on costs  alone).   The  transport costs  for  commercial
fertilizer are not that  significant, because the seller of the  product usually
locates near the centers of  use.

     Clearly,  a  great many  permutations  are possible  among transport  modes,
application  types  and rates  and crop types.  A  detailed  analysis of the many
alternative  combinations  is beyond  the  scope  of this  study.   The data  and
information,  however,  are presented  to  permit  a more detailed examination.


                                     82

-------
The application  rates  for  sludge affect costs.   Where sludge quantities are
small, e.g.,  P  injection application  to  sod in the  Mississippi  case, (see
Table 25), costs are high when compared to costs for application of commercial
fertilizer  and  when compared  to other states or  regions  where application
rates are higher.   In  general, the low sludge application rates result in an
unfair comparison  because  equipment  and other capital  costs  are annualized
with a poor economy of scale.

     Clearly, if sewage sludge  is to compete with  commercial  products for
supplying the necessary N and  P  for crop production,  the costs for operation
will  have to be  borne by  the municipality  generating the sludge.   If the
municipality would transport the  sludge to the site of application and provide
the application  equipment,  then  the  sludge  would  be a sought after product
when costs  for  this product  are  compared with the costs  for the commercial
product.
                                    83

-------

                                                             1000
                  CAPACITY - DRY TONS SOLIDS PER DAY
ENGINEERING NEWS RECORD:
   CCI - CONSTRUCTION COST INDEX = 3131, OCTOBER 1979 (1913=100)
U.S. DEPT. OF COMMERCE:
   CPI - CONSUMER PRICE INDEX = 226, OCTOBER 1979
DRY TONS (SHORT) x 0.9072 = DRY TONS (METRIC)
     Figure 8.  Costs of liquid sludge transport - 20 miles.
                                84

-------
10301	
                                                             1000
                CAPACITY - DRY TONS SOLIDS PER DAY
  ENGINEERING NEWS RECORD:
     CCI - CONSTRUCTION COST INDEX = 3131, OCTOBER 1979 (1913=100)
  U.S. DEPT. OF COMMERCE:
     CPI - CONSUMER PRICE INDEX = 226, OCTOBER 1979
  DRY TONS (SHORT) x 0.9072 = DRY TONS (METRIC)
       Figure  9. Costs of liquid sludge transport - 40 miles,
                                 85

-------
1000
                                                             1000
                   CAPACITY  -  DRY  TONS SOLIDS  PER DAY
  ENGINEERING NEWS RECORD:
     CCI - CONSTRUCTION COST  INDEX = 3131, OCTOBER 1979 (1913=100)
  U.S. DEPT. OF COMMERCE:
     CPI - CONSUMER PRICE  INDEX = 226, OCTOBER 1979
  DRY TONS (SHORT) x 0.9072 = DRY TONS (METRIC)
        Figure 10. Costs of liquid sludge transport - 60 miles,
                                  86

-------
vo
CM
CM
 II
»—i
Q_
O
CO
II
I—I
CJ

£

I

Of.
o
a:
LU
o.
CO
o
o

-------
  100
U3
CM
CVJ
 II
t—i
Q_
O
CO
ro
 i)
c_>
O
DC
Q

C£
UJ
D-

-t/>

 I
1/1
O
o

-------

ID
CVJ
CM
 II
I—i
ex.
o
n
n
 ii
CJ
<_>

10
^
o








10
                                   100

                   CAPACITY - DRY TONS SOLIDS  PER DAY
                                                             1000
    ENGINEERING NEWS RECORD:

       CCI  - CONSTRUCTION COST  INDEX  =  3131,  OCTOBER 1979 (1913=100)

    U.S.  DEPT. OF COMMERCE:

       CPI  - CONSUMER PRICE INDEX  = 226,  OCTOBER 1979

    DRY TONS (SHORT) x 0.9072 =  DRY TONS  (METRIC)
         Figure 13.   Costs of sludge  cake transport - 60 miles,
                                   89

-------
                                REFERENCES
1. Pietz-, R.I., J.R. Peterson,  C.  Lue-Hing,  and J.L. Halderson.  Rebuilding
   Topsoil  with  Municipal Sewage  Sludge Solids.   Report No.  78-12,  The
   Metropolitan  Sanitary  District of Greater Chicago,  Chicago, Illinois,
   1978. 22 pp.

2. United States Department of  Agriculture.   Final Environmental Statement,
   Palzo Reclamation Project,  Shawnee National Forest,  Williamson County,
   Illinois.  U.S. Forest Service, Milwaukee, Wisconsin, 1972.  102 pp.

3. Dean,  R.B.  Disposal   and  Reuse  of  Sludge and  Sewage:  What Are  the
   Options.  In: Proceedings of the Conference on Land Disposal of Munici-
   pal Effluents and Sludges.   EPA-902/9-73-001,  U.S. Environmental Protec-
   tion Agency, Washington, D.C., 1973.

4. Council for Agricultural Science and Technology.  Application of Sewage
   Sludge to Cropland: Appraisal  of  Potential Hazards  of The Heavy Metals
   to Plants and Animals.  EPA 430/9-76-013, U.S. Environmental Protection
   Agency, Washington, D.C., 1976. 63 pp-.

5. Water Resources Council.  Concepts, Methodology and Summary Data.  OBERS
   Projections  -  Economic  Activity in the  United  States,  Volume  I.
   Washington, D.C., 1972. 127 pp.

6. Farrell, J.B. Overview of Sludge  Handling and Disposal.   In: Municipal
   Sludge Management, Proceedings of the National  Conference on Municipal
   Sludge Management,  Am. Soc. of Civil  Engineers  and  U.S.  Environmental
   Protection Agency, Pittsburgh, Pennsylvania,  1974.  pp. 5-10.

7. Zenz, D.R., B.T. Lynam, C. Lue-Hing,  R. Rimkus, and T.D. Hinesly.  USEPA
   Guidelines  on  Sludge  Utilization  and Disposal; A Review  of Its Impact
   Upon  Municipal  Wastewater  Treatment  Agencies.   Report No.  75-20,  The
   Metropolitan  Sanitary  District of Greater Chicago,  Chicago, Illinois,
   1975.  70 pp.

8. Sommers,  L.E.,  D.W.  Nelson,  and K.J. Yost.    Variable  Nature  of  the
   Chemical Composition of Sewage Sludge. J. Environmental Quality, 5:303-
   306, 1976.

9. Sommers, L.E.,  and  D.W.  Nelson.   Analyses and Their Interpretation for
   Sludge Application.  In:  Application  of  Sludges and Wastewater on Agri-
   cultural Land:   A  Planning  and Educational  Guide,  B.D. Knezek and R.H.
   Miller, eds.  U.S. Environmental Protection Agency, Municipal Construc-
   tion Division, Washington,  D.C., 1978.  pp. 3.1-3.8.

                                   90

-------
10. Keeney, D.R., K.W. Lee, and L.M. Walsh.  Guidelines for the Application
    of Wastewater Sludge to Agricultural Land in Wisconsin.  Tech. Bullentin
    No. 88, Department of Natural Resources, Madison, Wisconsin, 1975.

11. King, L.D. Fate of Nitrogen from Municipal  Sludges.  In: Proceedings of
    the National Conference on Disposal of Sludge on Land. 1976.

12. North Central Regional Extension Publication No. 52.  Utilizing Munici-
    pal Sewage Wastewaters and Sludges on Land  for Agricultural Production.
    1977.                      •        -  "'
              ;
13. Sommers, L.E. Chemical  Composition of  Sewage  and Analysis  of Their Po-
    tential Use  as  Fertilizers.   J. Environmental Quality,  6(2):  225-232,
    1977.     \                       :

14. Sommers, L.E.,  and E.H.  Curtis.   Effect  of Wet-Air Oxidation  on the
    Chemial  Composition of  Sewage  Sludge.    J. Water Pollution  Control
    Federation, 49(11):. 2219-2225, 1977.          '   _-_           __

15. Peterson, J.R.,  C.  Lue-Hing, and  D.R.  Zenz.   Chemical  and Biological
    Quality of Municipal  Sludge.   In:  Recycling Treated  Municipal  Waste-
    water  and  Sludge  Through  Forest  and  Cropland,  W.E.  Sopper  and  L.T.
    Kardos,  eds.     Penn.  State   University  Press,   University   Park,
    Pennsylvania, 1973.  pp. 26-37.

16. Water  Pollution  Control  Federation.    MOP-8-Sewage  Treatment  Plant
    Design.  Washington, D.C., 1959.

17. Anderson, M.S.   Fertilizing Characteristics of  Sewage  Sludge.   Sewage
    and Industrial Wastes 31(6): 678-682, 1959.

18. Vesilind, P.A.  Treatment and Disposal  of Wastewater Sludges.  Ann Arbor
    Science Publishers, Inc., 1974.  236 pp.                •••:

19. Zenz, D.R., B. Sawyer, R. Watkins, C. Lue-Hing, and G. Richardson.  Eval-
    uation of  Dewatering  Equipment for Anaerobically Digested  Sludge.   J.
    Water Pollution Control Federation, 50(8):  1965-1975, 1978.

20. Price Quotation,  International  Minerals Corporation, Skokie, Illinois,
    January 1980.

21. Hoeft, R.G., and J.C. Siemens.  Do Fertilizers Waste Energy.  Crops and
    Soils Magazine, November 1975.

22. Price Quotation, Standard Oil Company, Chicago, Illinois, January 1980.

23. Mining Congress Journal, March 1976.

24. Heichel, G.H.  Comparative Efficiency of Energy Use in Crop Production.
    Report of the Connecticut Agricultural Experimental Station, 1974.
                                    91

-------
25. U.S.  Environmental  Protection  Agency,  Technology Transfer.    Sludge
    Treatment and Disposal.  EPA-625/4-78-012, Environmental Research Infor-
    mation Center, Cincinnati, Ohio, 1978.  140 pp.

26; Olexsey, R.A., and J.B.  Parrel!.  Sludge Incineration and Fuel Conserva-
    tion.  In:  News of Environmental Research in Cincinnati, May 1974.

27. Executive  Office  of  the  President,  Office  of Management  and  Budget.
    Standard Industrial Classification Manual.  General Services Administra-
    tion, Washington, D.C., 1972.  649 pp.

28. United States  Department  of  Agriculture,  Forest  Service.  Agricultural
    Conservation and Forestry Statistics, 1977.  Washington, D.C.,  1977.

29. Schery, R.W.   Plants for Man,  2nd  Edition.    Prentice  Hall,  Inc., New
    York, New York, 1972.

30. Sopper, W.E., andL.T. Kardos, eds. Recycling Treated Municipal Wastewater
    and Sludge Through  Forest and Cropland.   Penn. State  University Press,
    University Park, Pennsylvania, 1973.  479 pp.

31. Salo, D.J., J.F. Henry, and  R.E. Inman.  Design of  a Pilot Silvicultural
    Biomass Farm  at  the Savannah River Plant.   Tech.  Rep.  MTR-7960, Mitre
    Corporation, McLean, Virginia, 1979.  115 pp.

32. Inman, R.E., D.J.  Salo, and  B.J.  McGurk.   Silvicultural Biomass Farms,
    Site-Specific  Production  Studies  and Cost Analyses,  Volume  IV.   Tech.
    Rep. No. 7347, Mitre Corporation, McLean, Virginia, 1977.  159 pp.

33. Zavitkovsky, J. USDA/Forest Service, Rhinelander, Wisconsin, June 1978.
    In:  Design of a Pilot Silvicultural Biomass  Farm at  the Savannah River
    Plant.  Mitre  Corporation, McLean, Virginia,  1979.

34. United  States  Environmental  Protection  Agency,  Technology Transfer.
    Land Treatment of Wastewaters.  1975.

35. Kitzmiller, H.J., Jr.  Response  of Sycamore Families to Nitrogen Fertil-
    ization.   Technical  Report  No.  48,  North  Carolina State  University,
    School of Forest Resources, Raleigh, North Carolina,  1972.

36. Bonner, F.T.,  and W.M. Broadfoot.  Growth  Response  of Eastern Cottonwood
    to Nutrients in San Culture.  Note 50-65, U.S. Department of Agriculture,
    Forest Service Res., Southern Forest Exp. Sta., New Orleans, Louisiana,
    1967.

37. Sopper, W.E.   Crop Selection and Management  Alternatives - Perennials.
    In:  Proceedings of the Joint Conference on Recycling Municipal Sludges
    and  Effluents  on   Land,  U.S.  Environmental   Protection Agency,  U.S.
    Department  of  Agriculture,  Nat.  Assoc.  of State Universities and Land-
    Grant Colleges, Champaign, Illinois, 1973.  pp. 143-154.
                                    92

-------
38. Kenady, R.M.  Seedling Establishment in Soil  Receiving Dewatered Sludge.
    In:  Use of Dewatered Sludge as an Amendment for Forest Growth, Vol.  II,
    R.L.  Edmonds  and  D.W.  Cole,  eds.   Bulletin  No.  2,  University  of
    Washington,  Center  for Ecosystem  Studies, Seattle, Washington,  1977.
    pp. 45-54.

39. Urie,  D.H., A.R. Harris,  and J.H.  Cooley.    Municipal  and Industrial
    Sludge Fertilization of Forests and Wildlife Openings.   In:  Proceedings
    of the First Annual  Conference of Applied  Research  and Practice of Muni-
    cipal  and  Industrial  Waste.    U.S.   Forest   Service,  East  Lansing,
    Michigan,  1978.  pp. 467-480.

40. Mitre  Corporation.    Silviculture  Biomass Farms, Volumes  I-VI.   Tech.
    Rep. No. 7347.  McLean, Virginia, 1977.

41. Sopper,  W.E.,  D.R.  DeWalle,  and  S.N.  Kerr.   Utilization  of Municipal
    Wastewater  and Wast Heat for Energy Production  from Forest Biomass.  In:
    Proceedings  of the 1979  National  Conference  on Technology for Energy
    Conservation.   Information  Transfer,   Inc.,  Silver Spring,  Maryland,
•=- -1979. -pp.  572-581. 		:-	- —	-  -	- —- —  -  -  	-  .-.
              l
42. Einsphar,  D.W., M.K.  Benson,  and  M.L.  Harper.   Influence of Irrigation
    and Fertilization on  Growth  and  Wood  Properties of Quaking Aspen.  In:
    Proceedings of the Symposium on the Effect of Growth Acceleration on the
    Properties  of  Wood.   U.S.  Department  of  Agriculture,  Forest Service,
    Washington, D.C., 1972.
                    i.
43. Mitchell,  H.L.  Effect of Fertilizer on the Growth  Rate  and  Certain Wood
    Quality Characteristics of Sawlog Red Oak, Yellow-Poplar, and White Ash.
    In:  Proceedings of the Symposium on the .Effect of Growth Acceleration on
    the Properties of Wood.  U.S.  Department of Agriculture, Forest Service,
    Washington, D.C., 1972.

44. Saucier, J.R., and A.F. Ike.  Response  in  Growth and Wood Properties of
    American Sycamore to Fertilization and Thinning.  In:  Proceedings of the
    Symposium  on the Effect of Growth Acceleration on the Properties of Wood.
    U.S. Department of Agriculture, Forest Service, Washington, D.C., 1972.

45. Murphey, W.K., R.L.  Brisbin, W.J.  Young, and B.E. Cutter. Anatomical and
    Physical Properties  of Red Oak  and Red  Pine  Irrigated With Municipal
    Wastewater.    In:   Recycling  Treated  Municipal Wastewater and Sludge
    Through  Forest and  Cropland,  W.E.  Sopper and  L.T. Kardos, eds. Penn.
    State University Press, University Park,  Pennsylvania,  1973.  pp.  295-
    310.

46. Zasoski, R.J., S.G.  Archie, W.C.  Swain,  and J.D. Stednick.  The Impact of
    Sewage  Sludge  on Douglas  Fir Stands  Near Port Gamble.  University of
    Washington, College of Forest Resources,  1977.  42 pp.

47. Gouin,  F.R.,  C.B.  Link,  and O.F.  Kundt.   Forest  Seedlings  Thrive on
    Composted  Sludge.  Compost Science/Land Utilization: 28-30, July/August
    1978.

                                    93

-------
48. United States Department of Agriculture, Forest Service.  A Directory of
    Forest Tree Nurseries in the United States.  Washington, D.C., 1976.  33
    pp.

49. United States Department of Agriculture, Forest Service.  1976 Report -
    Forest Planting, Seeding, and Silvical Treatments in the United States.
    Washington, D.C., 1977.  13 pp.

50. Berry, C.R.,  and D.H.  Marx.   Sewage Sludge  and  Pisolithus  Tinctorius
    Ectomycorrhizae:  Their Effect on  Growth of Pine Seedlings.Forest Sci.
    22:351-358, 1976.

51. Prior, L.A.  Land Availability,  Crop  Production, and Fertilizer Require-
    ments in the United States.  EPA/530/SW-166, U.S. Environmental Protec-
    tion Agency, Washington, D.C., 1975.   99 pp.

52. Zenz, D.R., B.T. Lynam, C.  Lue-Hing,  R.  Rimkus, and T.D. Hinesly.  USEPA
    Guidelines on Sludge  Utilization  and Disposal;  A Review  of  Its Impact
    Upon  Municipal  Wastewater  Treatment  Agencies.   Report No.  75-20, The
   - Metropolitan-Sanitary  District  of Greater Chicago,  Chicago,  Illinois,
    1975.  70 pp.

53. Kirkham, M.B.  Growth of Tulips Treated with Sludge Containing Dewater-
    ing Chemicals.  Environmental Pollution 13: 11-19, 1977.

54. Kirkham, M.B.  Elemental Composition  of Sludge-Fertilized Chrysnthemums.
    J. Amer. Soc. Hort. Sci., 102(3): 352-354, 1977.

55. Epstein, E., and J.F. Parr.  Utilization of Composted Municipal Wastes.
    In: Proceedings of the 1977 National  Conference on Composting of Munici-
    pal  Residues and  Sludges,  Information Transfer,  Inc.,  and  Hazardous
    Materials Control Research Institute, 1977. pp.  149-153.

56. Lessley, B.V., and F.T. Arnold. Maryland Sod Production Costs, The Key to.
    Business Success.  Weeds, Trees and Turf:  44-47,  1977.

57. Tyson, J.  Sod  Growing in  Michigan.   Presented before Sod Nurserymen's
    Section, Midwest Regional Turf  Conference,  Purdue University,  Indiana,
    1977.

58. Darrah, C.H., J.R. Hall, and  J.J. Murray.   An Evaluation of Liquid and
    Composted  Sewage Sludge Utilization  in Turf  Production.   In:   Feasi^
    bility of  Using Sewage Sludge  for  Plant  and Animal  Production.   Uni-
    versity of Maryland, College Park, Maryland, and the U.S. Department of
    Agriculture, Washington, D.C., 1977.

59. Powell, A.J.,  and  J.R. Miller.   Lawn Care  in Maryland.  Bulletin 171.
    Cooperative  Extension  Service, University  of Maryland,  College  Park,
    Maryland, 1971.  24 pp.
                                    94

-------
60. Personal Communication, April 1978.

61. North  Central  Regional  Committee  NC-118.   Application  of  Sludge  and
    Wastewater on Agricultural Land:  A Planning and Educational Guide.  B.D.
    Knezek  and  R.H.  Miller,  eds.   MCD-35,  U.S. Environmental  Protection
    Agency, Municipal  Construction Division, Washington, D.C., 1978.  88 pp.

62. Schnell Publishing Company,  Inc.   Chemical  Marketing  Report.  December
    1979.  30 pp.

63. Personal Communication, Manufacturers of Chemical Fertilizer.

64. Personal  Communication,  Metropolitan  Sanitary  District  of  Greater
    Chicago, November 1979.

65. CH2M Hill, Inc., and Environmental Impact Planning Corporation.   Waste-
    water Solids Process, Transport  and  Disposal/Use  Systems,  Task  Report.
    San Francisco Bay Region Wastewater  Solids Study, Oakland, California,
    1977.  158 pp.    ...	

66. Haug,  R.Ti,  L.D.  Tortorici,  and S.K. Raksit.    Sludge  Processing  and
    Disposal, A State of the Art  Review.   Los Angeles/Orange County Metro-
    politan  Area  Project,  Regional  Wastewater Solids  Management Program,
    1977.  236 pp.

67. Roger Blobaum and Associates. An Assessment of the Potential for Apply-
    ing Urban Wastes  to Agricultural  Lands.   National Science  Foundation
    Grant No. AER77-08280.  West Des Moines, Iowa, 1979.  181 pp.
                                    95

-------
                                     TECHNICAL REPORT DATA
                             (Please read Inunctions on the reverse before completing)
1. REPORT NO.
                               2.
                                                              3. RECIPIENT'S ACCESSION»NO.
4. TITLE AND SUBTITLE

Production of Non-Food-Chain Crops with Sewage Sludge
              5. REPORT DATE
               Mav 1980 (issuing date)
                                                              6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Lilia A. Abron-Robinson, Cecil Lue-Hing,
Edward J. Martin, David Lake
                                                              8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
                                                              10. PROGRAM ELEMENT NO.
PEER Consultants, Inc. & Environmental Quality Systems
  Inc.
1160 Rockville Pike, Suite 202
Rockville. Maryland  20852	
                36HLC,  D.U.  yi21,- task C/38
              11. CONTRACT/GRANT NO.
                 68-03-2743
12. SPONSORING AGENCY NAME AND ADDRESS
Municipal Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati. Ohio 45268	
              13. TYPE OF REPORT AND PERIOD COVERED
               Research & Development	
              14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES

Project Officer:   Gerald Stern (513) 684-7654
16. ABSTRACT
 Feasibility and  market  potential were determined for non-food-chain crops  cultivated using
 sewage sludge.                                                      ........

 Non-food-chain  crops  that are currently  being sold  on the open market or that-have, a good
 potential for marketability were selected.  From a list of 20 crops, 3 were selected and subjected
 to a cost analysis to determine how the costs for cultivation using sewage  sludge compared with
 the costs for cultivation using commercial fertilizer.

 Cotton, sod, and energy biomass trees were determined to have the best potential for cultivation
 using sewage sludge, based on the market values and nutrient requirements for each crop, and on
 the hectares presently under cultivation for production of these crops.

 Results indicate that large quantities of sewage sludge can be used, based  solely on the  nitrogen
 and phosphorus requirements for the cultivation of these crops.  In addition, it was  determined
 that although the total costs for fertilization using commercial fertilizer are less than the costs
 for using sewage sludge, the  latter  would  be viewed more favorably if the costs were borne by
 the municipality generating the sludge.
17.
                                 KEY WORDS AND DOCUMENT ANALYSIS
                   DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
                                                                            c.  COSATI Field/Group
 Sludge, Sludge disposal, Cost comparison,
 Cost effectiveness, Cost estimates,
 Feasibility, Marketing value
 Non-food-chain crops,
 Marketing potential,
 Sewage sludge, Compari-
  son with commercial
  fertilizer
     13B
13. DISTRIBUTION STATEMENT

   RELEASE TO PUBLIC
19. SECURITY CLASS (This Report)
 UNCLASSIFIED
21. NO. OF PAGES

     108
                                                20. SECURITY CLASS (Thispage)

                                                 UNCLASSIFIED
                                                                            22. PRICE
EPA Form 2220-1 (9-73)

-------