vvEPA
                        United States
                        Environmental Protection
                        Agency
                        Office of Water
                        Washington, D.C.
EPA 832-F-00-052
September 2000
Biosolids
Technology  Fact Sheet
Alkaline  Stabilization of Biosolids
DESCRIPTION

Biosolids are primarily organic materials produced
during wastewater treatment which may be put to
beneficial  use.   Biosolids are  used in home
gardening,  commercial  agriculture,  silviculture,
greenways, recreational areas and reclamation of
drastically disturbed sites such as those subjected to
surface mining. Biosolids are often rich in nutrients
such as  nitrogen and  phosphorus,  and  contain
valuable  micro nutrients.   The  Environmental
Protection  Agency's (EPA) 40  CFR Part 503,
Standards for the Use and Disposal of Sewage
Sludge,  (the   Part   503  Rule)  requires  that
wastewater solids be processed before they can be
beneficially used. The processing is described in this
fact sheet as stabilization.  Stabilization helps to
minimize the potential for odor generation, destroys
pathogens (disease causing organisms), and reduces
the  material's vector  attraction potential.  One
method of stabilization is to add alkaline materials
to raise the pH level to make conditions unfavorable
for the growth of organisms (such as pathogens).
Figure 1  is a picture of alkaline stabilized biosolids
being dropped  from  an overhead conveyor into
windrow curing piles at Middlesex County Utility
Authority's facility in New Jersey.

The Part 503 Rule defines two types of biosolids
with respect to pathogen reduction:  Class A (no
detectable pathogens) and Class B (a reduced level
of pathogens). Both classes are safe, but additional
requirements are necessary with Class B materials.
These requirements are detailed in the Part 503 Rule
and include such things as limiting public access to
the  site of application, limiting livestock grazing,
and controlling crop harvesting schedules.  Class A
biosolids are not subj ect to these use restrictions and
can generally be used like any commercial fertilizer.
                      Alkaline stabilization can achieve the minimum
                      requirements for both Class A and Class B biosolids
                      with respect to pathogens, depending on the amount
                      Source: Parsons Engineering Science, Inc., 1999.

                          FIGURE 1 ALKALINE STABILIZED
                                      BIOSOLIDS

                      of alkaline material  added and other processes
                      employed. Generally, alkaline stabilization meets
                      the Class B requirements when  the pH of the
                      mixture of wastewater solids and alkaline material
                      is at 12 or above after 2 hours of contact.

                      Class A requirements  can be achieved when the pH
                      of the mixture is maintained at or  above 12 for at
                      least  72  hours,  with  a  temperature  of 52°C
                      maintained for at least 12 hours during this time. In
                      one process, the mixture  is air dried to over 50
                      percent solids after the 72-hour period of elevated
                      pH. Alternately, the process may be manipulated to
                      maintain temperatures at or above 70°C for 30 or
                      more minutes, while maintaining the pH requirement
                      of 12. This higher temperature can be achieved by

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overdosing with lime (that is, adding more than is
needed  to  reach a  pH of 12),    by  using a
supplemental heat source, or by using a combination
of the two.   Monitoring  for fecal  coliforms  or
Salmonella  sp. is required prior to release by  the
generator for use.

The Part 503 Rule also allows for meeting Class A
pathogen   reduction   requirements   through
monitoring   for  pathogens  before  and  after
processing.   For example, Class A Alternative 3
requires that the unprocessed wastewater solids be
monitored for enteric viruses and helminth ova. The
process is monitored for lime dosage and pH and
the final product must have no detectable  levels of
enteric viruses or helminth ova.

For more specific details on the requirements  for
achieving Class A or B, please refer to the Part 503
Rule.

Materials that may be used for alkaline stabilization
include hydrated lime, quicklime (calcium oxide), fly
ash,  lime and cement kiln dust, and carbide lime.
Quicklime is commonly used because it has a high
heat of hydrolysis (491 British thermal units) and
can significantly enhance pathogen destruction.  Fly
ash,  lime kiln dust, or cement kiln dust are often
used  for  alkaline stabilization  because  of their
availability and relatively low cost.

The  alkaline stabilized product  is  suitable  for
application in many situations, such as landscaping,
agriculture,  and mine reclamation.   The product
serves as a lime substitute, source of organic matter,
and a speciality fertilizer. The addition of alkaline
stabilized biosolids  results   in  more favorable
conditions for vegetative growth by improving soil
properties such as pH, texture, and water holding
capacity.  Appropriate applications depend on  the
needs of the soil and  crops that will be grown and
the pathogen classification. For example, a Class B
material would not be suitable for blending in a  top
soil mix intended for use in home landscaping but is
suitable  for  agriculture,  mine  reclamation,  and
landfill cover where the potential for contact with
the public is lower and access can be restricted.
Class A  alkaline stabilized biosolids  are useful in
agriculture  and  as   a  topsoil blend ingredient.
Alkaline stabilized biosolids provide pH adjustment,
nutrients, and organic matter, reducing reliance on
other fertilizers.

Alkaline stabilized biosolids are also useful as daily
landfill cover. They satisfy the federal requirement
that landfills must be covered with soil or soil-like
material at the end of each day (40 CFR 258). In
most cases, lime stabilized biosolids are blended
with other soil to achieve the proper consistency for
daily cover.

As  previously   mentioned,  alkaline  stabilized
biosolids are excellent for land reclamation in
degraded areas, including  acid mine spoils or mine
tailings.   Soil conditions  at such sites  are very
unfavorable for vegetative growth often due to acid
content, lack of nutrients, elevated levels  of heavy
metals,  and poor soil texture.   Alkaline stabilized
biosolids help to remedy  these problems, making
conditions more  favorable  for plant growth and
reducing  erosion potential.  In addition, once a
vegetative cover is established, the quality of mine
drainage improves.

APPLICABILITY

Where  lime  or  another  alkaline  additive  (for
example,  recycled   kiln  dust),   is  relatively
inexpensive, alkaline stabilization is often  the most
cost-effective  process  for  wastewater  solids
stabilization.   This  is  particularly true  where
dependable markets for the alkaline product can be
developed, such as in areas where alkaline materials
are  routinely  applied to  agricultural   soils to
maximize crop yields.

Alkaline stabilization is practical at small wastewater
treatment plants  that store  wastewater solids for
later transportation to larger facilities for further
treatment. It is also applicable as an expansion of
existing facilities or as anew facility to reduce odors
and pathogens. The technology is especially useful
at wastewater treatment facilities with flows that
vary greatly since the process   adjusts easily to
changing flows.   This  adaptability also makes
alkaline  stabilization an appropriate choice as a
secondary or backup stabilization  method because
these facilities can be started and stopped relatively
quickly  and easily. Facilities can also be designed to
handle either liquid or dewatered wastewater solids.

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In general, alkaline stabilization is not a proprietary
process, meaning that no fee is required to be paid
to a patent holder to use the process.  However,
several  variations  on  the  basic  process  are
proprietary, such as:

•      BioFIX Process (marketed by  Bio Gro
       Division of  Wheelabrator  Clean Water
       Systems, Inc.)

•      RDP  En-Vessel Pasteurization System
       (marketed by RDP Company.)

•      N-Viro  Advanced  Alkaline  Stabilization
       with  Drying   (marketed   by  N-Viro
       International Corporation.)

ADVANTAGES AND DISADVANTAGES

Alkaline  stabilization offers  several  advantages,
including:

•      Consistency  with  the  EPA's  national
       beneficial reuse policy. Results in a product
       suitable for a variety of uses and is usually
       able to be sold.

•      Simple  technology  requiring few special
       skills for reliable operation.

       Easy to  construct of readily  available parts.

       Small land area required.

       Flexible  operation,  easily  started  and
       stopped.

Several possible disadvantages should be considered
in evaluating this technology:

•      The resulting product is not  suitable for use
       on all soil.   For example, alkaline  soils
       common in southwestern  states  will not
       benefit  from  the addition  of a high pH
       material.

•      The volume of material to be managed and
       moved off-site is increased by approximately
       15 to  50 percent in comparison with other
       stabilization techniques, such as digestion.
       This  increased volume results in higher
       transportation costs when material is moved
       off-site.
       There is potential for odor generation both
       at the processing and end use site.

       There is a potential for dust production.

       There is a potential for pathogen regrowth
       if the pH drops below 9.5 while the material
       is stored prior to use (U.S. EPA, 1992.)

       The nitrogen content in the final product is
       lower than that in several other biosolids
       products.  During processing, nitrogen  is
       converted to ammonia, which is lost to the
       atmosphere  through  volatilization.    In
       addition, plant available phosphorous can be
       reduced through the formation of calcium
       phosphate.

       There are fees associated with proprietary
       processes (Class A stabilization.)
Environmental Impacts

There are several potential environmental impacts
associated with alkaline stabilization of wastewater
solids.  Odor problems may occur at the point of
processing or use due to the release of ammonia and
ammonia related compounds and amines.  These are
generally considered nuisance issues without long-
term  environmental impact.   Handling  of the
material, such  as loading, unloading, or spreading,
all potentially cause release of ammonia and amines.
The amount of ammonia released from the alkaline
stabilized product depends on the nitrogen content
of  the   wastewater  solids  and  the  pH  and
temperature achieved through the process.   The
extent of amine released will depend in part on the
nature of the dewatering chemicals used.

In addition, small amounts of parti culate matter may
be emitted by the processing facility, but these are
easily mitigated.

Land  application  of  any biosolid product  can
increase the concentrations of trace elements in the
soil.  Alkaline stabilized biosolids help to create soil
pH conditions in  which metals  are  insoluble,
minimizing plant uptake and movement of metals to
groundwater.

Soils which have a low pH will benefit greatly from
the alkaline material and will  be more fertile. Lime
is  usually low in metals  and, when blended with

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wastewater solids, can improve the quality of the
product with respect to metals.
DESIGN CRITERIA

There are many factors that must be considered in
designing an  alkaline  stabilization  facility  for
biosolids. The most critical are:

       Percent solids of infeed wastewater solids.

•      Desired  results (Class A versus Class B)
       which affect the amount of alkaline material
       needed and mixing time,  which, in turn,
       impacts equipment size.

•      Source and volume of alkaline material to be
       used.

•      Odor control equipment at the processing
       facility.

       Storage and curing areas.
The equipment necessary for alkaline stabilization is
relatively easy  to install and operate.   Typical
equipment includes the following:
                     •      Wastewater   solids   feed/conveyance
                            mechanism.

                     •      Lime storage (silo, 1000 or 50 pound bags,
                            etc.)
                     •      Lime transfer conveyor.

                     •      Mixer.

                     •      Air emission control equipment to minimize
                            odors and dust.

                     Figure 2 presents a typical flow diagram for alkaline
                     stabilization.  A list of general design parameters
                     and criterion for  Class B alkaline stabilization  is
                     found in Table 1.

                     Designing a facility to meet Class A stabilization
                     requirements may require additional lime storage to
                     allow  an  increased lime  dose, additional  curing
                     capacity, and/or the provision of supplemental heat.
       Storage Silo
                                                ->-Treated Air Vented to Atmosphere
                             Exhaust Air
                             „ Treatment
                                                         Process Air
             Alkaline
             Additive
Biosolids
f   Mixing  f  V
 Supplemental Heat
 Source or Alkaline
 Mixing to Achieve
^^   Class A   ^.

         i
         T
 i	••
 [ Product Curing  |
 !_ _ ai2d/?torage _  ]
                                                                                       Product
                                                                                     Distribution
Source: Parsons Engineering Science, Inc., 1999.
Note: Dashed lines indicate optional equipment.

   FIGURE 2  FLOW DIAGRAM OF A TYPICAL ALKALINE STABILIZATION OPERATION

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  TABLE 1  TYPICAL DESIGN CRITERIA
FOR CLASS B ALKALINE STABILIZATION
 Parameter
Design Criterion
 Alkaline dose
 Retention time in mixer
 Retention time in curing
 vessel
0.25 pound per pound of
wastewater solids at 20
percent solids
1 minute

30 minutes
 Source: National Lime Association, undated.

The end use of the material is another important
factor  when designing a  biosolids management
program,  including alkaline  stabilization.   The
resulting  material  is  suitable  for many  uses,
including agricultural application, mine reclamation
and landfill cover.  The amount of land that must be
available differs with the use. Alkaline stabilized
biosolids are generally lower in nitrogen than other
biosolids products because nitrogen is converted to
ammonia during processing. The material contains
approximately one to  two percent nitrogen; one
percent phosphorus;  and  negligible  potassium,
nutrients  of primary  importance  for vegetative
growth.    In  agricultural  application,   alkaline
stabilized biosolids  are often applied more for their
pH adjusting characteristics at a typical application
rate of two to five tons per acre. Nutrients supplied
to the crop are a secondary  benefit.  In reclamation
applications, the material is often applied only once
rather than annually or periodically as in agricultural
applications.  Therefore, the material is usually
applied at a higher rate of between 60 to  100 dry
tons per acre.  In landfill  cover applications, the
amount of  material  used  is dictated more  by
regulatory requirements  than nutrient  content.
Alkaline stabilized  biosolids can be used  as daily
cover,  or to amend the final cover, in accordance
with federal regulations which require  material to
enhance conditions for vegetative growth. For daily
cover,  a minimum of six inches of soil is required.
Equivalent thickness of alkaline stabilized  material
must be approved on a case by case basis.  Typical
application rates for incorporation into final cover
material are similar to those at mine reclamation
sites.
PERFORMANCE

Alkaline stabilization  is  frequently  selected by
wastewater  treatment  facilities in regions where
soils have a tendency to be acidic and where low
cost alkaline materials are readily available. In areas
where soils are acidic,  the end product has greater
value. Table 2 shows location, size, and end use for
representative alkaline stabilization facilities.

Alkaline stabilization  systems are generally quite
reliable  and flexible. The same equipment can often
be used to produce either Class A or B  biosolids
with minor process modifications, such as a larger
dosage  of alkaline material  or  the addition  of
supplemental heating (pasteurization.)

With respect to pathogen reduction, Class B alkaline
stabilization has been demonstrated to reduce total
coliform,  fecal  coliform,   and fecal  streptococci
bacterial concentrations by more than 99.9 percent.
Concentrations of Salmonella and Pseudomonas
aeruginosa have been  shown to be reduced below
the level of detection.  Pathogen concentrations in
Class B alkaline stabilized biosolids range from  10
to  1,000 times  less than  those  in  anaerobically
digested sludge  (U.S. EPA,  1979.)    Alkaline
stabilization can result in an exceptional quality
product when it meets Class A pathogen reduction,
vector attraction reduction  and the highest standards
for metal concentrations.   This higher  level  of
processing can result in a more valuable product
because there are no restrictions on end use.  The
high level  of disinfection  achieved  in  Class  A
products makes them easier to handle and apply.
For example, if a farmer purchases an exceptional
quality product, he will not have to restrict access or
limit grazing and harvesting times.

The appearance,  odor  causing  potential,  and
handling characteristics can vary greatly depending
on the type  of alkaline stabilization process used.
Processes that  add  larger amounts of  alkaline
material or include added heat, drying, or curing will
produce a drier product  that  resembles topsoil.
Other  alkaline stabilization processes that simply

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              TABLE 2  REPRESENTATIVE LIME STABILIZATION FACILITIES
Solids
Location Production Disposal/End Use
(dry tons/day)
Hampton Road, VA
Reedsville, Wl
Lancaster, OH
Raleigh, NC
Howard Co., MD
Cookeville, TN
Charlotte, NC
Washington, DC
Middlesex, NJ
Toledo, OH
Greenville, SC
Tarpon Springs, FL
Syracuse, NY
Urbana-Champagne, IL
Upper Gwynedd, PA
Bergen County, NJ
8
1-2
3
20
20
<1
20
270
146
63
10
3
30
5
2-3
45
Land Application
Land Application
Land Application
Land Application
Land Application
Land Application
Agricultural Liming Agent
Land Application
Landfill Cover
Agricultural Liming Agent
Agricultural Liming Agent
Landfill Cover
Land Application
Agricultural Liming Agent
Land Application
Land Application
Landfill Cover
Pathogen
Reduction
Class A
Class A
Class A & B
Class A
Class A & B
Class A
Class A
Class B
Class A
Class A
Class A
Class A
Class A
Class B
Class B
Class A
Process Employed
Bio*Fix
EnVessel
Pasteurization™
Bio*Fix
N-Viro AASAD
Bio*Fix
EnVessel
Bio*Fix
Post-Lime Stabilization
N-Viro AASAD
N-Viro AASAD
N-Viro AASAD
N-Viro AASAD
N-Viro AASAD
N-Viro
Generic
Bio*Fix
Source: National Lime Association, 1995; RDP Technologies, Inc. web site, 1999;
personal communication with facility operators.
            N-Viro International Corp. web site, 1999, and
add enough lime to increase pH to 12 for 2 hours
may  still  resemble  biosolids  cake  from  the
dewatering equipment.  The characteristics of the
end product should be considered when evaluating
the methods and  feasibility of storage.  Drier
alkaline  stabilized products tend to  have fewer
odors after 30 days or more of storage.  On the
other hand, cake-like  products  should be used as
soon as possible to minimize odor complaints at the
application sites.

The  odors  associated  with  alkaline  stabilized
products are also dependent on the characteristics of
the wastewater  solids.    Plant  operators  who
minimize sludge age in  the  their  wastewater
treatment facility will also minimize odor generation
both at the processing facility and at  the end use
site.   In  addition, 25  percent total solids cake is
easier to process  and requires  less lime than 20
percent total solids cake.  The odors also result
from the dewatering chemicals used.

OPERATION AND MAINTENANCE

Alkaline  stabilization   systems   are   relatively
uncomplicated facilities  operated with the skills
found   in  typical  wastewater  treatment plant
personnel.   Labor requirements  include  heavy
equipment operators, maintenance personnel, and
instrumentation/computer operators.

The caustic nature of the  alkaline additive requires
higher  maintenance  on  these systems  than on
stabilization systems that do not involve caustic
materials.   Proper design  and operation of the
mixing  equipment is  necessary  to  ensure  a
consistent, homogeneous product.

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COSTS

It is difficult to estimate the costs of stabilizing
biosolids with alkaline materials without specific
details, such as wastewater solids characteristics and
quantities.  One study estimated costs for Class A
alkaline stabilization ranging from $139 to $312 per
dry ton of wastewater solids processed by facilities
designed to  serve  wastewater treatment  plants
ranging in capacity from 10 to 60 million gallons per
day.   This  estimated  range  demonstrates  the
economy of scale associated with larger systems.
The capital costs cited in this same study ranged
from $1.5 to $4.0 million and  annual costs were
estimated to range from $1 million and $4 million.
This study concluded that alkaline stabilization was
less expensive than composting or thermal drying
(Sullivan, 1996.)

Although exact costs for alkaline stabilization
cannot be provided,  the following  items must be
considered in estimating costs for any alkaline
stabilization facility:

•      Processing   equipment  purchase   and
       installation.

•      Product curing and storage facilities.

       Loading facilities.

•      Transport of product to point of use.

       Royalty and operating fees  for proprietary
       processes.

•      Equipment maintenance and fuel.

       Alkaline additive.

•      Labor.

       Odor control equipment and chemicals.

•      Marketing costs/revenues.
•      Regulatory compliance,  such  as  permit
       applications,  site  monitoring,  biosolids
       analyses, and regulatory record keeping and
       reporting.

The incremental capital cost for meeting Class A
requirements through alkaline stabilization is the
lowest among  stabilization  alternatives  such as
thermal drying and anaerobic and aerobic digestion.
The incremental unit cost (including capital and
operation and maintenance) associated with creating
a Class A product from a system currently making
a Class B product and serving a 5 million gallon per
day wastewater treatment facility was estimated to
be $39 per dry ton. Again, this is significantly less
than the unit costs to increase pathogen treatment
through aerobic or anaerobic digestion, which were
cited  as $88 and $103  per dry  ton, respectively
(National Lime  Association, 1998.)

Some generators of alkaline stabilized biosolids sell
the product for approximately $3 to $5 per wet ton.
REFERENCES

Other Related Fact Sheets

Odor Management in Biosolids Management
EPA 832-F-00-067
September 2000

Centrifugal Dewatering/Thickening
EPA 832-F-00-053
September 2000

Belt Filter Press
EPA 832-F-00-057
September 2000

Land Application of Biosolids
EPA 832-F-00-064
September 2000

Other EPA Fact Sheets can be found at the
following web address:
http://www.epa.gov/owmitnet/mtbfact.htm

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Backmann, F., 1942. Emergency Treatment    9.
of Army Camp Sewage. Engineering News-
Record. July 16, 1942.

Christy, P.O.,  1990.  Process Equipment    10.
Considerations  For  Lime  Stabilization
Systems Producing PSRP and PFRP Quality
Sludge. In Proceedings of Water Pollution
Control Federation Conference: The Status
of Municipal Sludge Management for the    11.
1990 's.

Christy, R.W. Sr., 1990.  Sludge Disposal    12.
Using  Lime.    Water  Environment  &
Technology. 2: 56-61.

Forste, J., 1996. Agricultural Use of Lime
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10th  Annual  Residuals  and  Biosolids    13.
Management Conference:  10  Years  of
Progress and a Look Toward the  Future.
Alexandria: Water Environment Federation.

Hatfield, N.L. and Burnham, J.C., 1994.
Characterization of Odors in Untreated and
EQS   Processed  Dewatered  Municipal    14.
Wastewater Sludges. In Proceedings of the
Odor  and  Volatile  Organic  Compost
Emission  Control Specialty Conference.
Alexandria: Water Environment Federation.

Males, E. 1998. National Lime Association,
Reference Sheet.

Metcalf & Eddy, Inc., 1991.  Wastewater
Engineering  Treatment,  Disposal,  and    15.
Reuse   Third Edition.    San  Francisco:
Irwin/McGraw-Hill.

Muhs,  G. P., 1999. The Design  and  Cost
of Class A and B Treatment of Biosolids
Using   Post-Lime  Stabilization  and
Pasteurization.      Available   at
[http://www.rdptech.com].
National Lime Association, 1995. Biosolids
Booklet (Bulletin 334, Edition 1). Edited by
J.D. Robinson. Arlington, Virginia.

National Lime Association, 1998. Biosolids
Treatment:     Comparing  Add-On
Stabilization  Processes.   Bulletin  335.
Arlington: National Lime Association.

N-Viro International Corporation's Web
Site  [http://www.nviro.com], 1999.

Northwest   Biosolids   Management
Association (NBMA). "Biosolids Q & A
Environmental  Effects."    Available  at
[http://www.nwbiosolids.Org/biosolidsqa/e
nvironment.html], July 1999.

Oerke, D.W.,  1989.   The Role of Lime
Stabilization  Processes  In   Wastewater
Sludge  Processing and  Disposal.    In
Effective   Use  of Dry Lime for Sewage
Sludge Stabilization.   Arlington: National
Lime Association.

Smith, K.A., Goins L.E., and Logan T.J.,
1996.  Effect  of Lime Dose  on Thermal
Reactions  and  Physical  Properties  of
Alkaline  Stabilized   Biosolids.     In
Proceedings of the 10th Annual Residuals
and Biosolids Management Conference: 10
Years of Progress and a Look Toward the
Future.   Alexandria: Water Environment
Federation.

Sullivan, D.G, Oerke, D.W., 1996.  Which
Class A Biosolids  Stabilization Process is
the Most Economical: Lime Stabilization,
Composting  or  Thermal  Drying?    In
Proceedings of the 10th Annual Residuals
and Biosolids Management Conference: 10
Years of Progress and a Look Toward the
Future.   Alexandria: Water Environment
Federation.

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16.    U.S. EPA, 1994. A Plain English Guide to
       the  EPA  Part  503  Biosolids  Rule.
       EPA/832/R-93/003,  U.S.     EPA,
       Washington, D.C.

17.    U.S.  Environmental  Protection  Agency,
       1993. Standards for the Use or Disposal of
       Sewage  Sludge  (40 Code  of Federal
       Regulations Part 503). Washington D.C.:
       U.S. Environmental Protection Agency.

18.    U.S   EPA,   1999.      Environmental
       Regulations and Technology: Control  of
       Pathogens and Vector Attraction in Sewage
       Sludge. U.S. EPA, Washington, D.C.

19.    U.S. EPA, 1979.  Process Design Manual
      for Sludge Treatment and Disposal. U.S.
       EPA, Washington, D.C.

20.    Weissinger, T. and Girovich, M.,  1994.
       Evaluation  of a Chemical  Stabilization
       Process. Remediation. Winter 1994. pp.
       77-99.
Valley Forge Sewage Authority
Rick Taylor
333 Pawling Road
Phoenixville, Pennsylvania 19460
The mention of trade names or commercial products
does not constitute endorsement or recommendation
for use by  the  U.S.  Environmental Protection
Agency.
21.     Wheelabrator Water Technologies, Inc. Bio
       Gro Division,  1996.  Bio*Fix  Alkaline
       Stabilization.

ADDITIONAL INFORMATION
District of Columbia Water and Sewer Authority
Chris Peot
5000 Overlook Avenue, SW
Washington, D.C. 20032

Middlesex County Utility Authority
Richard Fitamont
One Main Street Extension
Sayreville, New Jersey 08872

National Lime Association
200 North Glebe Road, Suite 800
Arlington, Virginia 22203
          For more information contact:

          Municipal Technology Branch
          U.S. EPA
          Mail Code 4204
          1200 Pennsylvania Ave., N.W.
          Washington, D.C. 20460
                                                            MTB
                                                           Excelence fh tompfance through optfhial tethnltal solutfons
                                                           MUNICIPAL TECHNOLOGY BRANCH

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