State/EPA Regional Policy
on
Municipal . Sludge Management
New England Interstate
Water Pollution Control Commission
United States
Environmental Protection Agency
Region I — New England

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STATE/EPA REGIONAL POLICY
ON
MUNICIPAL SLUDGE MANAGEMENT
Prepared by: New England Interstate Water
Pollution Control Commission
and
Environmental Protection Agency
Region I — New England
DECEMBER 1978

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FOREWORD
As a result of the construction and operation of wastewater treatment
plants designed to reduce the pollutants discharged to our waterways, signifi-
cant quantities of sludge are being produced each day. The utilization or
disposal of the sludge is a problem being faced by municipalities throughout
New England and the Nation. The resolution of this problem has been
hindered, in part, by the absence of comprehensive State or Federal guidelines
for evaluating utilization and disposal alternatives. Working through the New
England Interstate Water Pollution Control Commission, the water pollution
control agencies of the New England States have moved ahead to establish
uniform policies for guiding the development of sludge management pro-
grams. This paper represents the culmination of a joint effort by the Commis
sion and the Region I office of the U. S. Environmental Protection Agency to
develop policies which provide the necessary State flexibility for implementa-
tion and, at the same time, encourage environmentally sound municipal
sludge utilization and disposal programs. In concurrence with a recommenda-
tion from its Technical Advisory Board, the Commission voted on June 23,
1978 to adopt this policy paper.
The policies outlined herein are intended to serve as a general guide to the
design engineer, the regulatory agencies and the public in selecting environ-
mentally acceptable procedures that are both operationally practicable and
economically feasible. In doing so, it is important to recognize that although
State and Federal grants support the capital investment for sludge manage-
ment facilities, it is the municipality which must implement the sludge
management program and carry the burden of operational expenses.
It is not the intent of this document to provide detailed information on the
design procedures for various sludge handling and disposal methods. For such
information, the reader is referred to the sources listed in Appendix A. In
addition, the appropriate State regulatory agencies must be contacted to
determine specific limitations or restrictions that may apply to a particular
project.

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INTRODUCTION
The processing and disposal of the sludge produced during wastewater
treatment is the source of many health and environmental hazards. Existing
methods often contravene known principles of good practice; however, some
environmentally acceptable alternatives are almost prohibitively expensive for
particular plants. Problems of plant operation are frequent and troublesome.
In most situations, it is not easy to find an operationally reliable, environmen-
tally sound and financially acceptable method of sludge disposal and get it
implemented.
The foregoing statements are based on observations and reports made by
local, State and Federal officials in New England. At the present time, efforts
to make a detailed assessment of the Region's municipal sludge management
practices are hindered by the lack of a comprehensive data base. However,
such information is presently being obtained and catalogued by State and
Federal agencies and should be complete within the near future.
Recent amendments to the Federal Water Pollution Control Act and the
Solid Waste Disposal Act1 included requirements for the Environmental Pro-
tection Agency (EPA) to develop guidelines for disposal and management of
municipal sludge. In November 1977, EPA published a technical bulletin on
municipal sludge management.2 The bulletin addresses environmental factors
of various sludge management options and does so in a general manner to
allow maximum flexibility to meet varying regional needs. Additional criteria
for land disposal of sludge were proposed by EPA in February 19783, and
numerous EPA technical reports on sludge disposal have been published as well.
Although Federal legislation has directed the EPA to develop and imple-
ment a national policy on municipal sludge management, it nevertheless re-
mains the primary role of the States to translate that policy into programs that
provide for sound management and oversight of sludge disposal practices. In
view of the numerous differences that exist among the New England States, it
is unreasonable to expect that specific requirements and restrictions of their
sludge utilization and disposal programs will be identical. Similarly, the States
may in some instances choose to differ from EPA regulations by imposing
stricter requirements on the use of various utilization or disposal options. How-
ever, there are certain aspects which will be common to all programs and in
which both the States and the Federal government can concur. The purpose of
issuing this regional municipal sludge management policy is thus one of estab-
lishing general guidance for acceptable practices in the New England States.
It is preferred to have sludge disposed in a beneficial way by taking full
advantage of its resource potential. The most common beneficial use of sludge
is via land application for its effect on soil properties and for the plant
nutrients it contains. This can be accomplished either by direct application or
after an intermediate step such as composting. A less frequent use of sludge is
for its fuel value.
It is well recognized that the disposal of sludge, even for beneficial uses,
carries with it the risk of serious and long term environmental degradation
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unless proper design and operational procedures are followed. For land appli-
cation, the hazards are: 1) the transmission of bacteria and virus infections and
of parasitic organisms, 2) the introduction of toxic materials into the soil with
consequent injury to crops, or through the food chain to animals and to
humans, 3) the pollution of ground and surface water supply sources, 4) the
pollution of surface waters, and 5) nuisance conditions which result from some
practices. To assure reasonable protection against these hazards, the land use
methods and precautions set forth herein are considered necessary.
The extraction of fuel value from sludge also poses some environmental
hazards as well as technical difficulties. For incineration and pyrolysis pro-
cesses, the primary hazards are associated with stack gas emissions and with ash
disposal. The incineration of sludge frequently requires auxiliary fuel con-
sumption, although recent work has shown that sludge can be co-incinerated
with processed municipal refuse at a substantial reduction in supplemental
fuel requirements. However, anaerobic digestion of sludge, in which the gas
produced has a fuel value of about 600 Btu/cu. ft., has virtually no environ-
mental hazards associated with it. Of course, the plant operator is still faced
with disposal of the digested sludge, but the digestion process results in a well-
stabilized sludge that can be readily dewatered and/or applied to the land,
transported to a landfill or disposed of by some other means.
The alternatives to beneficial use of sludge are: 1) dewatering and either
pyrolysis or incineration (with no heat recovery), with ash usually buried in a
landfill, and 2) burying in a sanitary landfill either separately or in combina-
tion with solid waste. Each of these alternatives has its advantages and its
hazards, many of which are similar to those discussed above. Although ocean
disposal is currently used at one location in New England, it is due to be
phased out by 1982 and is therefore not considered to be a viable alternative
for new or existing systems.
Sludge is by no means a uniform commodity. Its composition depends
upon its source, and particularly on the industrial wastes which may be
discharged to the sewer system for joint treatment. Small communities without
significant industrial waste may safely be exempted from some of the precau-
tionary measures required for larger systems. Larger communities may find
that instituting an industrial pretreatment program will significantly affect the
community's options for sludge disposal.
Although the Environmental Protection Agency and the State and local
agencies responsible for sludge management are primarily regulatory, and
although innovative methods involve extra risk and extra effort, EPA makes
explicit provision for full consideration and encouragement of new and im-
proved methods. It is hoped that State and local authorities will, when oppor-
tunity offers, share in reasonable developmental risks to advance the transfer
into practice of improved technology.
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LAND APPLICATION
Priorities
Land application is probably the most common beneficial use for waste-
water sludge and should always be given consideration on new projects and
major revisions or extensions of existing projects. For the purposes of this policy
document, land application includes those disposal methodologies which make
use of the beneficial nutritive and soil-conditioning properties of sludge.
In view of the present uncertainty about the public health risks of various
food-chain uses for sludge, nonagricultural uses with minimum public contact
are generally preferred. The following list presents a recommended order of
preference for sludge utilization via land application:
1.	Remote or controlled areas of minimum public contact, such as strip-
mine reclamation or sand-dune stabilization projects, and forest land.
2.	Highway embankment and cut stabilization, golf courses, parks, high-
way median strips, and final cover on sanitary landfills.
3.	Fiber and non-food-chain crops.
4.	Fodder crops and pasture land.
5.	Agricultural land used for crops to be cooked.
6.	Agricultural land used for crops which may be eaten raw.
The selection of any utilization scheme is based upon a number of factors,
not the least of which is site monitoring requirements. It might therefore be
desirable to utilize a disposal option of lower preference where only one site is
involved rather than an option of higher preference with multiple sites that
would make monitoring difficult. Similarly, uses of higher potential risk (i.e.,
lower order of preference) may be selected in specific cases, provided adequate
precautions are implemented and sludge characteristics are generally good,
such as in rural areas. For example, the application of sludge to agricultural
land used for growing crops which may be eaten raw might require additional
sludge disinfection or a waiting period prior to planting.
Sludge Characteristics
Many factors affect the suitability of land disposal, the methods to be
used, and the monitoring and other precautionary measures necessary.
Perhaps the simplest to consider first are the sludge characteristics.
Disinfection and Stabilization
Before disposal of sludge to the land, it is usually advantageous to stabilize
its organic content and substantially reduce its population of pathogenic
organisms. This lessens the danger of nuisance odors and transmission of infec-
tion. In especially favorable sites, small quantities of materials such as excess
extended aeration sludge may be used without further stabilization or
disinfection.
Anaerobic digestion has been the most frequently used method of
stabilization. It converts the sludge to a relatively stable material without
objectionable odor, and substantially reduces its content of enteric organisms.
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Adequate stabilization is achieved when volatile solids are reduced by at least
40 per cent, which in the absence of toxic substances takes about 30 days at
80°F. In high-rate anaerobic digestion, adequate stabilization is achieved after
10 days at 95°F. Fecal coliforms, and presumably also pathogenic bacteria,
will typically be reduced by at least 97 per cent.
Composting is a stabilization method which is of increasing interest and
practicality. Recent advances make it possible to compost raw sludge rapidly
without nuisance odors. Other methods of sludge stabilization are aerobic
digestion, lime treatment to high pH, heat treatment and heat drying, and
proprietary chemical treatment processes. Lime treatment requires the
maintenance of high pH in the soil so that the sludge decomposes gradually
and does not cause nuisance odors. Although incorporating the sludge into the
soil reduces the odor potential, the application of additional lime may be
necessary if the sludge destabilizes too rapidly. Chemical treatment involving
chlorine oxidation is currently in question since chlorinated organics of
unknown toxicity and carcinogenicity are produced. Nuisance odors, which
strongly influence acceptability of land use of sludge, can be avoided with
proper operation of chlorine oxidation facilities.
Additional Pathogen Reduction
For some agricultural or public-contact applications, or for projects
involving special wastes, pathogen reduction beyond what is afforded by the
stabilization methods described above may be necessary. The methods listed in
EPA's technical bulletin are as follows: 1) pasteurization (30 minutes at 70°C),
2)	high pH treatment, typically with lime, at a pH greater than 12 for 3 hours,
3)	long term storage of liquid-digested sludge for 60 days at 20 °C or 120 days at
4°C, 4) composting to completion, in which the entire mass reaches a
temperature of at least 55 °C and is then stockpiled to cure for at least 30 days,
and 5) both gamma and high energy electron ionizing radiation under various
application procedures.
Toxic Substances
The amounts of heavy metals, pesticides, persistent organics such as PCB,
radionuclides and other toxic materials4 present in the sludge are the main
determinants of suitability for land application. The potential hazards posed
by these materials include contamination of surface or ground waters, toxicity
to plants, and increased contamination of the food supply by potentially toxic
substances, Contamination of an important ground water aquifer can be a
serious problem because of the relatively slow rate of natural purification even
after the removal of the source of contamination. The presence of these
materials will thus limit the application rates and may influence the selection
of a cover crop for the site. The heavy metals of primary concern are cad-
mium, lead, zinc, nickel, chromium, mercury, arsenic, selenium, molybde-
num, and copper, all of which can accumulate in plants and may pose a
hazard to plants, animals or humans. In some instances, the implementation
of industrial pretreatment programs may eliminate the presence of these toxic
materials in the municipal sludge.
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System Classification
For reasons of relative environmental importance and control require-
ments, the municipal wastewater treatment systems of the Region are for pur-
poses of land application of sludge divided into three classes: 1) systems of
minimum concern with a design capacity of one million gallons per day (MGD)
or less, with no known significant industrial wastes (also includes unsewered
areas with on-site disposal systems), 2) systems of intermediate concern with a
flow up to 5 MGD and acceptable sludge characteristics and monitoring provi-
sions, and 3) systems of major concern involving larger urban areas. Any
system in which the sludge is found to contain significant levels of toxic or
hazardous materials shall be classified as a system of major concern.
Based on 1970 census figures, the number of systems and corresponding
population in each class are estimated as follows:
Systems	Population

Number
Percent
Number
Percent
Minimum Concern: Unsewered
37
8.0
2,469,528
20.8
Flow < 1 MGD
353
76.1
1,033,004
8.7
Intermediate Concern
47
10.1
935.784
7.9
Major Concern
27
5.8
5,208,902
62.6
Site Selection
The characteristics of the application site are as significant a factor as
sludge characteristics in determining the acceptability of a sludge manage-
ment program. As outlined below, selection and evaluation of alternative sites
will be a function of several factors.
Present and Future Land Use
As noted earlier, the priority of non-agricultural land uses will apply. In
addition to the disposal site itself, consideration must be given to the surround-
ing land uses. In order to avoid odor problems or other issues which might
create adverse public reactions, land application sites should be isolated as
much as possible from residential areas. The anticipated future land uses of
the site as well as the surrounding areas should be evaluated for compatability
over the expected life of the site as well as over the expected time period during
which the site, after its closure, will continue to have an effect on the environ-
ment. Specific non-compatible uses, such as location of a land application site
within a surface water supply watershed, may be designated by some States
and can be determined by contacting the appropriate State regulatory agency.
Size and Number of Sites
In general it is easier and less costly to maintain and assure a well-run
operation on relatively few sites, each using a substantial portion of the total
sludge available, than on many scattered locations. In some cases, however,
there may be justification for making sludge available to holders of smaller
plots, even at some increase in operating cost.
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Topography
Well-drained land of fairly gentle and uniform slope is ideal. Steeper
slopes may cause polluting surface runoff to the nearest watercourse, or re-
quire construction of dams, holding ponds or similar works to avoid creating
such pollution. Rugged or irregular terrain may increase the cost of sludge
application and limit the methods which can be used. Wet or waterlogged land
is generally unsuitable for beneficial use of sludge and is generally incompati-
ble with adequate protection of ground and surface waters for other uses.
Some exceptions, such as aquacultural demonstrations, may have merit and
should not be arbitrarily disallowed, but will require careful individual evalua-
tion to assure adequate protection of ground water supplies, wildlife, and
other legitimate uses of the environment.
Ground Water Hydrology
Ground water (i.e., leachate) migration from the site must not be permit-
ted to pollute ground water sources already in use or needed for future
development of the region, nor to adversely affect surface waters. The necessity
to both monitor such sites continuously and to have an alternative site
available to accept the sludge if incipient deterioration does occur should be
considered. The presence of adjacent ground water uses or values may also
affect the amount of sludge which may be applied in any time interval, and the
extent to which it should be dewatered. In general, sludge should not be
applied under circumstances where it may reasonably be expected to have a
harmful effect on potable water supply wells.
Geology
The nature of the surface layer and subsurface structure of the area
affects the operation in several ways. First, the cation exchange capacity of the
soil in relation to the cation concentrations in the sludge will determine the
total cumulative amount of sludge which may safely be applied, and thus the
life of the site, unless other problems develop sooner. The formula recom-
mended by the USDA, Agricultural Research Service, and the EPA is a useful
guide providing a margin of safety for agricultural practice, and should be
observed unless specific justification for an exception can be demonstrated.
The formula5 is as follows:
Metal	Soil Cation Exchange Capacity (meq/100g)*

0-5
5-15
>15


(Maximum metal addition, kg/ha)

Pb
500
1000
2000
Zn
250
500
1000
Cu
125
250
500
Ni
50
100
200
Cd
5
10
20
•Determined on soil prior to sludge application using the pH 7
ammonium acetate procedure.
Second, soil permeability in relation to rainfall, water table and its
seasonal variations, and water content of the sludge, affects the dosage and
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timing of sludge to be applied and method of application. Adequate sludge
storage facilities (e.g., impermeable lagoons) must be available at the plant or
the application site to provide sufficient storage capacity for winter and other
periods when sludge application is not feasible. Consideration should be given
to the need for odor control at such storage facilities.
Finally, the geologic structure below the surface soil layer can play an im-
portant role in some cases. The presence of impervious layers can direct
ground water migration, sometimes in directions which would not be expected
from surface topography. Such layers may also protect underlying aquifers
from contamination. The channeling which often occurs in limestone areas
may carry waters rapidly for long distances with little opportunity for ion ex-
change or other purification. Where these factors are known or suspected, they
should be considered in site evaluation.
Monitoring
Monitoring requirements for land application of municipal sludge are
desirable to insure proper operation of the site, including crop production, as
well as protection of ground and surface water quality. As described below,
monitoring requirements will vary with the size and type of land application
method, but in all cases they should address sludge characteristics, soil condi-
tions, ground water impacts and cover crop contamination. Environmental
monitoring is encouraged because it represents a direct measure of any adverse
effect, and therefore of compliance. However, environmental monitoring pro-
grams may be very expensive and in many cases may not be necessary. In such
cases, utilization of proper operational controls should provide for achieve-
ment of environmental goals. This is especially true for one-time sludge (or
compost) applications, for low rates of application per acre, and for well-
stabilized sludge or compost with low metal and other toxic element content.
Sludge Monitoring
Sludge composition should be monitored to assure that its application to
the land will not introduce toxic materials to the environment and to deter-
mine the application rates and procedures. The methods of sludge stabiliza-
tion and subsequent use, rather than sludge analysis per se, are relied upon to
assure that its application will not transmit pathogenic organisms nor cause
significant odor or other nuisance conditions.
Communities with wastewater treatment plant capacity of 1 MGD or less
and no significant industrial waste contribution should have one representative
sample of the winter sludge accumulation analyzed for metals and any other
constituents of environmental concern that because of local factors might be
expected to be present. The following table lists both maximum allowable
metals concentrations for projects of minimal concern, and also lower target
concentrations which should be attainable for domestic sewage with no in-
dustrial waste or with best available pretreatment:
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(Concentration in Milligrams per dry kilogram)
Cation
Zinc
Copper
Nickel
Cadmium
Lead
Mercury
Chromium
T arget
750
250
25
5
500
2
50
Maximum
2500
1000
200
25*
1000
10
1000
"Cadmium should not exceed 1% of the concentration of zinc;
however, for concentrations of 25 ppm or less, adverse effects
will take several decades to develop at recommended rates of
application to agricultural land.
If the sludge is otherwise qualified for agricultural application, available
nitrogen and total Kjeldahl nitrogen should be determined for use in calculat-
ing application rates. Phosphorus and potassium determinations on the sludge
are not usually required, since meeting the nitrogen requirement of the crop
should automatically supply sufficient phosphorus, and potassium content of
the sludge can be assumed negligible. In cases where sludge is applied to non-
agricultural land, the application rate should be based on preventing pollution
of ground waters and surface waters (via runoff) as well as soil condition re-
quirements for present and future site uses.
Projects of intermediate concern, if they comply with the sludge quality
requirements for projects of minimal concern as demonstrated by each of three
successive quarterly samples, need continue sampling only quarterly while the
sludge quality remains in compliance and there is no known significant new
source of pollution. Since sludge use will probably be periodic, the analyses
should be timed to determine the quality of the accumulated sludge before it is
used on agricultural land.
Projects of intermediate concern not complying as above may be required
to determine the concentrations of critical contaminants more frequently, and
to undertake an abatement program and schedule for the reduction of
contaminants at least to the above maxima, to assure that their sludge can be
used on agricultural land beneficially.
Major urban areas and other places not qualifying for lesser concern must
be treated individually on a case-by-case basis, with sludge monitoring and all
other aspects of the operation regulated as necessary for continued agricultural
productivity and environmental protection.
Soil Monitoring
Before any sludge is applied to agricultural land, the soil at each site
should be sampled and analyzed for heavy metals, pH and cation exchange
capacity and each year before sludge is applied, the soil should be analyzed for
pH and plant nutrients. The total and available nitrogen analysis of the soil
and the sludge, in relation to the crop to be planted, normally determine the
amount of sludge per acre which should be applied. This will normally provide
ample phosphate, which is adsorbed and held available for plant growth in the
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soil. Supplemental potassium fertilizer will probably be required for optimum
productivity.
Ground Water Monitoring
In general, ground water monitoring requirements should be related to
the characteristics of the applied sludge and the rate of application. For pro-
jects of minimal concern applying sludge within the cumulative limit for heavy
metals and annual dosage not exceeding 5 dry tons per acre the first year and
half that amount in subsequent years, no special ground water monitoring is
necessary for most sites. Nitrate concentration and sanitary quality should be
monitored annually in water from any adjacent wells which could possibly be
affected. In special cases, ground water monitoring may be made a condition
for site approval or later required for continued operation if problems arise.
For projects of intermediate concern, if they comply with the foregoing
cumulative and annual dosages for heavy metals and in addition comply with
USDA recommended maximum application of nitrogen for the crop grown on
the site*, minimal ground water monitoring will suffice in the absence of
special site problems.
Wells within one-half mile with hydrostatic level below the elevation of
the ground to which sludge is applied should be monitored twice annually for
sanitary quality, dissolved solids and nitrates. If there is reason to suspect the
presence of pesticides or related compounds, or other potentially toxic
materials leaching from the sludge, these too should be determined. Public
water supplies will also conform with the more frequent monitoring re-
quirements of the Safe Drinking Water Act (PL 93-523) and any amendments
thereto and regulations thereunder. Where special site problems exist, it may
be necessary to provide monitoring wells between the site boundary and an
existing well or ground water supply of importance for future development, so
that with timely warning the water supply can be protected. Sampling fre-
quency will be increased as necessary t<3 determine a course of corrective action
and assess its effectiveness. Among possible corrective actions are changes in
sludge dewatering, stabilization, application method and rate, temporary or
* Annual rates of sludge application on land should be the lower of the following two values (1 or
2):
1.	Nitrogen requirement of the crop (inorganic N = 20% organic N).
a.	When incorporated — sludge should be applied at no more than
100% of the crop requirement for N.
b.	When surface applied sludge should be added at no more than 150%
of the crop requirement for N.
2.	Cadmium loadings on land should not exceed 1 kg/ha/yr at most sites
and not more than 2 kg/ha/yr under good site conditions and good
management practices.
Sludge having a cadmium content greater than 1.5 percent of its zinc content should not be
applied on a continuing basis unless there is an abatement program to reduce the quantities of
cadmium in the sludge to an acceptable level. These metal additions apply only to soils that are
adjusted to pH 6.5 or greater when sludge is applied, and are to be managed at pH 6.2 or
greater thereafter (soil pH determined by 1:1 water, or equivalent method).1
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permanent suspension of sludge use at a site, soil amendments to control pH,
temporary or permanent special water treatment, and temporary or perma-
nent switch to an alternative water supply source.
Large urbanized areas, and smaller population centers where special
problems are encountered, require individual study and a program of opera-
tion specifically designed for the needs of the unique situation.
Crop Monitoring
The safety of food crops entering commerce is primarily the responsibility
of the Food and Drug Administration. The Environmental Protection Agency
has responsibility for assuring that operators of wastewater sludge utilization
projects are aware of FDA requirements and in communication with FDA.
For foods to be eaten raw, except for crops such as tree fruits, where
methods of sludge application and crop harvesting assure no contact between
the food part of the plant and the sludge or the soil, FDA recommends that
three years shall elapse between sludge use and crop harvesting.
For foods to be cooked or otherwise effectively processed, when grown on
sludged land, FDA requires testing for specified pathogens with negative
results.
When sludge is applied to pasture land, care should be taken to avoid
contact between applied sludge and grazing animals. Forage and pasture crops
should not be consumed by these animals when physically contaminated by
sludge which has not been removed from the crop by rain or other means.
Leafy vegetables are not a desirable crop for sludged land. If they are
grown, monitoring the crop for metals content is recommended by USDA, and
the Agricultural Extension Service agent should be consulted on analyses,
methods and acceptable levels.
Cereals and seed crops are desirable, since heavy metal content of the seed
tends to be low, even when high in the plant as a whole. Monitoring these crops
should not be necessary if limits on annual and cumulative sludge application
contained herein are observed.
SANITARY LANDFILLS
The disposal of sludge in a sanitary landfill is an acceptable practice
where suitable sites are available. In July 1979, EPA is expected to promulgate,
in final form, criteria for solid waste disposal facilities, including landfills, as
required by the Resource Conservation and Recovery Act of 1976 (PL 94-580).
This law requires the States to upgrade the operation of the landfills to meet
these criteria. At present, State and local regulatory agencies differ in their re-
quirements for acceptance of municipal sewage sludges for landfilling. For
example, combining sludge with solid waste in landfills is acceptable in some
areas but not in others.
The design and operation of a landfill for disposal of sewage sludge should
take into consideration precautions for protection of public health, ground
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water protection, and prevention of nuisance odor conditions. Normally,
sludge stabilization and the daily soil cover will prevent nuisance odors.
Ground water contamination may occur as a result of leachates from landfills
receiving sewage sludges. Such leachates may contain heavy metals, persistent
organics (pesticides, PCB's, etc.) and other compounds covered by drinking
water standards. It is therefore recommended that an appropriate monitoring
program be developed and implemented for landfills accepting sludge. Such a
program, to be specifically designed for each site, should include ground water
observation wells and, where applicable, surface water monitoring.
INCINERATION
The use of incineration as part of the sludge disposal option significantly
reduces the volume of waste for ultimate disposal, which is a major concern
where land availability is a problem. In the past, substantial energy inputs
have been required either for dewatering the sludge or for auxiliary fuel pur-
poses. However, some future plants may achieve self-sustaining combustion
once incineration has begun, thereby reducing auxiliary fuel needs. Recent
demonstration projects have shown that co-incineration of sludge with
municipal refuse can eliminate the need for auxiliary fuels. Also, energy
recovery techniques are being used in conjunction with some recent units as a
means of achieving a more favorable energy balance for the system. The
development and demonstration of such technologies should be encouraged
and supported by Federal, State and local officials.
The environmental hazards associated with incineration include ash
disposal and air quality degradation. The design of ash disposal systems should
provide for ground water protection from leachates, dust prevention, and pro-
tection against erosion to surface waters. Criteria for systems will be developed
under PL 94-580.
In order to prevent air quality hazards, the sludge incinerators must meet
EPA air pollution emission standards of performance contained in the New
Source Performance Standards for Sludge Incinerators (40 CFR 60.15, Appen-
dix IV). The ultimate goal is to prevent violation of ambient air quality stan-
dards. A program of industrial pretreatment may be necessary to control
specific emissions such as volatilized mercury, persistent organics, radioactive
materials, PCB's, and particulates containing trace amounts of metals such as
lead and cadmium.
A monitoring program for stack gas emissions must be established for
each sludge incinerator. The program must be designed to provide a means of
measuring compliance with existing EPA regulations (40 CFR 60.15, Appen-
dix IX; and, for mercury emission, 40 CFR 61.52). Additional monitoring for
oganic pesticides, PCB's or heavy metals may be necessary for specific projects.
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PYROLYSIS
Pyrolysis is defined as the gasification and/or liquefaction of a combusti-
ble material by heat, either in the total absence or in the presence of a con-
trolled amount of oxygen. The gas which is produced from pyrolysis of sludge
has a heat value of up to 130 Btu/std. dry cu. ft., using air for combustion,
and is suitable for use in many applications. Pyrolysis is much more efficient
than incineration because of the small amount of excess air to be heated, and
the resultant decrease in amount of supplemental fuel and size of gas handling
facilities required often makes pyrolysis much more economically attractive.
The environmental hazards associated with pyrolysis are similar to those
stated for incineration, i.e., control of stack gas emissions and ash disposal.
The ash from pyrolysis has a higher content of combustibles (up to 30%) than
that from incineration. Co-pyrolysis of sludge and refuse derived fuel (RDF)
with energy recovery has also been shown to be feasible.
OCEAN DISPOSAL
Sludge disposal in the ocean, although used for 15% of the national
sludge volume, is used in Region I only by the City of Boston. At the present
time, ocean dumping of sludge is being done only under interim permits,
because the sludge does not meet ocean dumping criteria. Sludge dumping is
scheduled to be phased out by 1982, and therefore it is not considered to be a
viable alternative for New England municipalities.
12

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REFERENCES
1.	Clean Water Act Amendments of 1977 (PL 95-217) and Resource Conser-
vation and Recovery Act of 1976 (PL 94-580).
2.	Municipal Sludge Management: Environmental Factors (MCD-28), EPA
430/9-77-004, U.S. Environmental Protection Agency, October 1977.
3.	"Proposed Criteria for the Classification of Solid Waste Disposal
Facilities", 40 CFR Part 257, Federal Register, Vol. 43, No. 25,
4942-4955, February 6, 1978, U.S. EPA, Washington, D.C.
4.	"List of 65 Toxic Pollutants Pursuant to Section 307(a) (1) of FWPCA, As
Amended", Federal Register, January 31, 1978, p. 4108 (see also Natural
Resources Defense Council et al v. Train, No. 73-2153, DC DC, June
1976).
5.	Municipal Sludge Management: Environmental Factors, U.S. EPA, Octo-
ber 1977.
6.	King, L. D., "Mineralization and Gaseous Loss of Nitrogen in Soil-
Applied Liquid Sewage Sludge", Journal of Environmental Quality,
2:356 358 (1973).

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APPENDIX A
Bibliography of Sludge Design Manuals and Related Publications
1.	Municipal Sludge Management: Environmental Factors, (MCD-28) EPA
430/9-77-004, U.S. EPA, October 1977.
2.	Sludge Treatment and Disposal — 1977 Design Seminar Handout, Envi-
ronmental Research Information Center, U.S. EPA, 1977.
3.	Sludge Handling and Disposal Practices at Selected Municipal Waste-
water Treatment Plants, MCD-36, EPA 430/9-77-007, U.S. EPA, April
1977.
4.	Wastewater Sludge Utilization and Disposal Costs, (MCD-12), EPA 430/9-
75-015, U.S. EPA, September 1975.
5.	Process Design Manual for Sludge Treatment and Disposal, U.S. EPA
Technology Transfer, October 1974.
6.	First Progress Report on Static Pile Composting of Wastewater Sludge
(#2014), U.S. EPA Technology Transfer, 1978.
7.	Process Design Manual for Municipal Sludge Landfills, U.S. EPA Envi-
ronmental Research Information Center, October 1978.
8.	Sludge Treatment and Disposal (2 volumes), U.S. EPA Environmental
Research Information Center, October 1978.
Ol/VOOOlbZ'f 9. Applications of Sludges and Wastewaters on Agricultural Land: A Plan-
ning and Educational Guide, (MCD-35), U.S. EPA Office of Water Pro-
gram Operations (Reprinted with permission of Ohio State University),
March 1978.
10.	Guides for the Design of Wastewater Treatment Works, (TR-16), New
England Interstate Water Pollution Control Commission, Boston, Massa-
chusetts (Revised edition 1979).
11.	Wastewater Treatment Plant Design, (MOP-8), Water Pollution Control
Federation, Washington, D.C., 1977.

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OCLC Connexion
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OCLC 1141781462 Held by EHA - no other holdings
Rec stat n Entered 20200225 Replaced 20200225
Type a ELvl K Srce d Audn	Ctrl
BLvl m Form	Conf 0 Biog	MRec
Lang eng
Ctry mau
Cont b GPub f LitF 0 Indx 0
Desc i	Ills a Fest 0 DtSt s Dates 1978 ,
040	EHA *b eng *e rda *c EHA
088	EPA 901-R-78-011
099	EPA 901-R-78-011
049	EHAD
245 0	0 State/EPA regional policy on municipal sludge management / *c prepared by: New England Interstate
Water Pollution Control Commission, and Environmental Protection Agency, Region I.
264	1 [Lowell, MA]: #b New England Interstate Water Pollution Control Commission, *c 1978.
264	1 [Boston, MA]: *b Environmental Protection Agency, Region I
300	12 pages : *b tables ; *c 26 cm
336	text *b txt +2 rdacontent
337	unmediated *b n *2 rdamedia
338	volume *b nc +2 rdacarrier
500	"December 1978."
504	Includes bibliographical references.
650	0 Sewage sludge *x Environmental aspects #z New England.
650	0 Sewage disposal plants *x Environmental aspects *z New England.
710 1	United States. *b Environmental Protection Agency. *b Region I. *e issuing body.
710 2	New England Interstate Water Pollution Control Commission, *e issuing body.
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