EPA-600/2-77-145
August 1977
Environmental Protection Technology Series
ACTINOMYCFTES OF
SEWAGE-TREATMENT PLANTS
Municipal Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL PROTECTION TECH-
NOLOGY series. This series describes research performed to develop and dem-
onstrate instrumentation, equipment, and methodology to repair or prevent en-
vironmental degradation from point and non-point sources of pollution. This work
provides the new or improved technology required for the control and treatment
of pollution sources to meet environmental quality standards.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/2-77-145
August 1977
ACTINOMYCETES OF SEWAGE-TREATMENT PLANTS
by
Hubert A. Lechevalier, Mary P. Lechevalier
Waksman Institute of Microbiology
Rutgers, the State University of New Jersey
Piscataway, New Jersey 08854
and
Paul E. Wyszkowski
Consulting Engineer
Warren, New Jersey 07060
Grant No. R803701
Project Officer
Ronald F. Lewis
Wastewater Research Division
Municipal Environmental Research Laboratory
Cincinnati, Ohio 45268
MUNICIPAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U. S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
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DISCLAIMER
This report has been reviewed by the Municipal Environmental
Research Laboratory, U,S. Environmental Protection Agency, and
approved for publication. 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 recommendation for use.
11
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FOREWORD
The 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 testimony to
the deterioration of our natural environment. The complexity of
that environment and the interplay between its components re-
quire 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 for the prevention, treatment, and management of waste -
water and solid and hazardous waste pollutant discharges from
municipal and community sources, for the preservation and treat-
ment of 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; a most
vital communications link between the researcher and the user
community.
This report covers studies of attempts to control nuisance
Nocardia foams in full scale activated sludge plants by adding
anaerobic digester supernatant containing suspended solids that
were toxic for the Nocardia. The results of tests at four full-scale
plants are reported along with conclusions of the best method for
the addition of the anaerobic digester supernatant.
Francis T. Mayo
Director
Municipal Environmental Research
Laboratory
111
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ABSTRACT
In some sewage-treatment plants of the activated sludge type, a
thick foam rich in species of Nocardia may be formed at the surface
of the secondary aeration and settling tanks. This report covers the
work done on this problem between May 1975 and May 1976.
It had been observed previously that the supernatant from anaerobic
digesters contained suspended solids which were toxic for Nocardia.
In the present study we observed that this material is toxic for some
bacteria and not for others.
In four sewage -treatment plants equipped with anaerobic digesters,
attempts were made to control the foam by returning the supernatant
from the digesters.to the primary system. The nocardiotoxicity of
the supernatant solids was tested to be sure that nocardiotoxic
material was being returned into the system.
The amount of nocardia present was estimated visually and by
measuring by gas chromatography the amount of nocardomycolic
acids present in the suspended solids.
The results indicated that this method of control is difficult to use at
the plant level and indicates that better results might be obtained if
the toxic supernatant was added directly to the activated sludge
aeration basins rather than added to the incoming sewage or the
primary settling basins.
It is also concluded that a more rational approach to the method of
control would be possible if the nature of the nocardiotoxic
principle(s) of the anaerobic digested material was known.
This report was submitted in fulfillment of Grant No. R803701 by
the Waksman Institute of Microbiology under the partial sponsorship
of the Environmental Protection Agency. The reported work was
completed as of May 1976.
IV
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CONTENTS
Page
Disclaimer ii
Foreword iii
Abstract iv
Figures vii
Tables viii
Acknowledgments ix
Sections
I Introduction 1
II Conclusions 4
III Recommendations 5
IV Methods 6
V Spectrum of Antimicrobial Activity of Anaerobic 12
Digester Supernatant Solids
VI The Bernardsville Plant 14
VII The Florham Park Plant 15
VIII The Middletown Plant 34
DC The Ocean Township Plant 51
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CONTENTS (Continued)
Page
X Comparison of the Results Obtained at the 69
Florham Park, Middle town and Ocean
Township plants
XI The Bayshore Plant 73
XII Discussion 78
XIII References 80
VI
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FIGURES
Number Page
1 Flow Diagram. Sewage Treatment Plant - 16
Florham Park Sewerage Authority
2 Nocardiotoxicity of the Supernatant from the 31
Anaerobic Digester and Nocardomycolate
Contents of Sludge Solids at the Florham Park
Plant from July 1 to October 13, 1975
3 Flow Diagram. Sewage Treatment Plant - 35
Township of Middletown Sewerage Authority
4 Nocardiotoxicity of the Supernatant from the 50
Anaerobic Digester and Nocardomycolate
Contents of Sludge Solids at the Middletown
Township Plant from June 10 to November 3,
1976
5 Flow Diagram. Sewage Treatment Plant 52
Township of Ocean Sewerage Authority
6 Nocardiotoxicity of the Supernatant from the 67
Anaerobic Digester and Nocardomycolate
Contents of Sludge Solids at the Ocean Township
Plant from August 1 to November 4, 1976
VII
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TABLES
Number Page
1 Field Observations Florham Park Plant 17
2 Analysis of Return Activated Sludge 22
Florham Park Plant
3 Analysis of Digester Supernatant - 24
Florham Park Plant
4 Plant Operating Records (Weekly Averages) - 25
Florham Park Plant
5 Field Observations - Middletown Plant 36
6 Analysis of Return Activated Sludge 41
Middletown Plant
7 Analysis of Digester Supernatant - 43
Middletown Plant
8 Plant Operating Records (Weekly Averages) 44
Middletown Plant
9 Field Observations - Ocean Plant 53
10 Analysis of Return Activated Sludge - 58
Ocean Plant
11 Analysis of Digester Supernatant - Ocean Plant 60
12 Plant Operating Records (Weekly Averages) - 61
Ocean Plant
13 Sludge Age in Days 70
14 Field Observations - Bayshore Regional Plant 75
15 Operating Records - Bayshore Regional Plant 77
Vlll
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ACKNOWLEDGMENTS
We wish to thank the operators of the various New Jersey plants who
cooperated in this study and the municipal operating agencies as
follows:
Mr. Nicholas Sapio, Plant Manager, Florham Park Sewerage
Authority.
Mr. Dennis Broderick, Plant Superintendent, Township of
Middletown Sewerage Authority.
Mr. Harold Johnson, Laboratory Director, Township of Middletown
Sewerage Authority.
Mr. Robert Rogove, Superintendent, Township of Ocean Sewerage
Authority.
Mr. Robert Buckingham, Plant Superintendent, Borough of
Bernardsville.
Mr. Harris Layton, Superintendent, Bayshore Regional Sewerage
Authority.
IX
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SECTION I
INTRODUCTION
GENERAL
We have previously reported on the presence and the role of
different types of Nocardia in the thick foam which is formed at the
surface of the secondary aeration and the settling tanks of some
sewage-treatment plants of the activated sludge type. This work
has been described in report EPA-600/2-75-031 of the Environmental
Protection Technology Series, which was published in September
1975. We reported then that we had observed that the solids found
in the supernatant of anaerobic digesters were toxic to Nocardia
amarae (Lechevalier and Lechevalier, 1974), the organism most
commonly associated with the production of foams. We
recommended that the chemical nature of the nocardiotoxic principle
should be elucidated and that attempts should be made to control
foaming at the plant level by returning anaerobic digester supernatant
into the system.
We are presently reporting on the work that we have carried out
between May 1, 1975 and May 31, 1976 involving the addition of
regulated amounts of supernatant from anaerobic digesters to the
flow stream of plants known to have a nocardial foaming problem.
We selected four New Jersey wastewater treatment plants equipped
with anaerobic digesters that were known to have actinomycetic
foams during the summer. These were the plants at Ocean
Township, Middletown Township, Bernardsville and the Somerset
Raritan Valley Sewerage Authority in Bridgewater Township. As
we were ready to start our study we were informed that the last plant
had discontinued using anaerobic digesters. We dropped it from our
study and replaced it with the Florham Park plant.
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The plan of the study was to observe these plants until actinomycetic
foam would occur. During that waiting period, supernatant return
from the anaerobic digesters was to be kept to a minimum. After
the development of a significant amount of actinomycetic foam had
occurred, controlled amounts of nocardiotoxic anaerobic super-
natant were to be returned into the system in an effort to control
the actinomycetic foaming.
The field work was started in May 1975 and was terminated in
November of the same year. It consisted in weekly monitoring the
four wastewater treatment plants previously mentioned. During the
weekly visits to each of these plants the physical appearance of the
activated sludge was checked and a visual estimate of the foaming
problem was made (Tables 1, 5 and 9). In addition, unusual
operating conditions were noted and samples of the returned
activated sludge and of the anaerobic digester supernatant were
collected. Further, the plant operators supplied us with copies of
their records containing information on flow, temperature, pH,
suspended solids and BOD determinations (Tables 4, 8 and 12).
The weekly samples of return activated sludge collected at the
plants were analyzed by us for pH, solid concentration and the
presence of Nocardia amarae by two different methods (Tables 2, 6
and 10). One of the methods was qualitative, being the microscopic
examination of the samples for the presence of nocardial hyphae.
The other was quantitative, and involved the gas chromatographic
determination of the nocardomycolic acids of N. amarae. This last
method is based on the fact that N. amarae produces a unique type
of lipid, a nocardomycolic acid whose a branch is mono-
unsaturated. The rationale behind the utilization of this
quantitative assay was that as the foam builds up with the warming
of the weather, the hyphae of N. amarae become more abundant
and the nocardomycolate content increases. The assumption was
made that if the addition of anaerobic digester was reducing the
nocardial growth, this would be accompanied with a reduction in the
nocardomycolate content of the suspended solids.
The samples of anaerobic digester supernatants were checked for
pH and nocardiotoxicity (Tables 3, 7 and 11). The pH of all
supernatants tested were neutral. This assay was carried out since
it was felt that there was no point returning a non-nocardiotoxic
supernatant to a foaming plant.
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OBJECTIVE
The purpose of this study was to determine if the addition of
nocardiotoxic supernatant from anaerobic digesters to the raw
sewage flowing into plants with nocardial foaming would control
the foaming which is considered a nuisance in the operation of
activated sludge sewage-treatment plants.
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SECTION II
CONCLUSIONS
Attempts were made to control actinomycetic foaming in the
secondary aeration and settling tanks of four activated sludge type
sewage-treatment plants by adding controlled amounts of
nocardiotoxic anaerobically digested material to the sewage flow.
In addition to the nocardiotoxicity of the anaerobically digested
material, success seemed to depend on the plant design. Favor-
able design should permit the operator 1) to waste the Nocardia-
infected foams to the anaerobic digester in order not to keep re-
inoculating the secondary tanks with large biomasses of Npcardia,
and 2) to add the nocardio-toxic material to the secondary flow
into the activated sludge in order to prevent its partial removal by
primary treatment system.
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SECTION in
RECOMMENDATIONS
The production of actinomycetic foams should be prevented because
the growth of nocardias in aeration tanks is a health hazard due to
the formation of Nocardia-containing aerosols and, in addition, the
production of thick foams in activated sludge type plants interferes
with treatment efficiency and is a source of extra labor costs. In
plants affected with nocardial foam, the foam should be skimmed
off the secondary settling tanks and sent to the anaerobic digester.
This should be done to reduce the amount of Nocardia in the
secondary treatment system.
We feel that a pilot study should be run in properly equipped plants
with anaerobic digesters to test the value of returning controlled
amounts of nocardiotoxic anaerobic digester supernatant directly to
the secondary flow stream.
It is also our recommendation that the chemical nature of the
nocardiotoxic compound(s) be determined. If the nature of the
nocardiotoxic material were known it might be possible to add small
amounts of the active compound(s) which might be effective without
applying an appreciable waste load to the system as is commonly
experienced with supernatant returns. This last study would have the
added benefit of increasing our knowledge of the chemical nature of
anaerobically digested materials.
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SECTION IV
METHODS
Isolation of Nocardia from sewage.
Method.
Samples of sewage sludge or foam were diluted in sterile distilled
water to give final dilutions of 10 , 10"^ and 10"^. A tenth of ml of
these dilutions were spread on the surface of 6-10 plates containing
Czapeks-Yeast Extract, Potato-Car rot, and Glycerol-Nutrient
agars. After incubation of the plates at 28 °C for 10-14 days,
actinomycete colonies were picked and streaked on fresh plates to
determine morphology and freedom from contamination by other
microorganisms. N. amarae strains grew as dry, beige, wrinkled
colonies on all media. N. rhodochrous colonies were usually some
shade of pink or orange (sometimes very light) and varied in
consistency from very "runny" to quite dry.
Monitoring of Nocardia amarae chemical.
Monitor mycolate procedure.
Extraction.
Samples of activated sludge were autoclaved at 15 Ib. /sq. in. for 25
min, cooled, and the solids collected by centrifuging 250 ml aliquots
at 5, 000 rpm for 10 min in a Lourdes P-Fuge (4100 xg). The wet
solids were air-dried to constant weight, and the dried solids ground
to a fine powder in a Thomas-Wiley Intermediate Mill Model 3383-
L40. Five gm of this powder were saponified in 75 ml 2%
methanolic potassium hydroxide by boiling in a 250 cc Erlenmeyer
over a steam cone for 7 min. The solids were separated from the
supernatant by filtration through fluted Reese-Angel 802 filter paper.
The filtrate was labelled "extract #1. " The solids were rinsed with
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hot methanol, replaced in the original flask and extracted by boiling
in distilled methylene chloride for 2 rain on the steam cone. The
solvent was separated from the solids as before by filtering into a.
fresh flask, then the solids extracted once with fresh methylene
chloride. Care was taken to "squeeze-dry" the solids to obtain all
the extract. The two methylene chloride extracts were combined
and labelled "extract 2" and taken to dry nes sin vacuo with mild heat
(40 °C).
Purification.
Extract #1 was neutralized carefully to pH 7. 0 with 6N hydrochloric
acid and taken to dryness in a Buchi Rotovapor Model RE at 55 ° C
under vacuum provided by a Buchler Water Booster #2-9000. Extract
2 was taken to dryness similarly without pH adjustment. Extract #1
and extract #2 were each separately treated in the following way: The
dry residue •was dissolved in 5-10 ml of methylene chloride, 5-10 ml
of distilled water added, the water adjusted to pH 2. 0 with 2N HC1 and
the two phases thoroughly mixed for 1 min on a Vibromix. The two
phases were completely separated by centrifuging at 3, 000 RPM in an
International Clinical Centrifuge (1200 xg), and the aqueous (upper)
phase discarded. The methylene chloride of the lower phase was
removed under vacuum in a tared tube and the tube placed for complete
drying in a vacuum oven (National Appliance Co. Model No. 5851)
using concentrated technical sulfuric acid as desiccant.
Methylation.
The dried extracts #1 and #2 were weighed, then methylated by boiling
with 10% boron trichloride-methanol (Applied Science, State College,
Pa.) (3 ml of reagent for 200 mg of residue) until the reagent went
to dryness. The dry methylated material was dissolved in methylene
chloride and washed three times with distilled water by mixing on a
vibrator-mixer and centrifuging to break any emulsion as described
above. The aqueous washes were discarded. The last wash had a
pH 5. 0-6. 0. If the pH of the final wash was too low, the washing was
continued. The organic (lower) layer of each extract was taken to
dryness under vacuum in a tared tube.
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Preparative thin-layer chromatography (PTLC).
Each methylated extract was weighed and the weight recorded. Each
was dissolved in methylene chloride and fifty mg or less were spotted
as a band 2 cm from the bottom of a 20 x 10 cm PF~(- . silica gel plate
(Brinkmann Instruments, Westbury, N. Y.) containing 10 g of silica
per plate. The bands were dried under warm air, then developed in a
solvent system, containing petroleum ether:diethyl ether in proportions
of 8:2 (b. p. >40). When the solvent front had reached the top of the
plate, the plate was air-dried under a hood, then sprayed with
Rhodamine B (0. 1% ethanolic Rhodamine B diluted 1:10 with 0.25 M
KHUPCK). The band(s) migrating at an Rf corresponding to the
methyl nocardomycolates from Nocardia amarae were carefully
scraped off, and dried overnight at room temperature. The silica of
the bands was eluted by 10X by volume distilled methylene chloride,
and the eluate reduced in volume by heating at ry 40° C on a hot plate
under a stream of compressed filtered air. The samples were
transferred to tared tubes, the solvent driven off and the residues
taken to dryness in vacuo and weighed.
Analysis by gas chromatography.
Ten meg of the samples to be analyzed were injected in 0. 5 A of
methylene chloride into a Varian Gas Chromatograph Model 2800
equipped with a flarne-ionization detector. Conditions were:
injector port 300° C, detector 300 ° , column temperature
programmed at 6° /min from 185° to 285 ° . Columns 6' x 1/8" of
10% OV-1 on Chromosorb W, AW-DMCS, 100-120 mesh were used.
Under these conditions the mycolates in the sample pyrolyzed to give
rise to a straight chain fatty acid methyl ester according to the
following reaction:
O
ft ? i //
OH RX OCH3 H OCH3
Mycolic acid Meroalde- Fatty acid
Methyl ester hyde methyl ester
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The fatty acid peak corresponding to the fatty methyl ester (methyl
octadecenoate) from the pyrolysis of the nocardomycolic acids of N.
amarae (amaraemycolate) was identified on the basis of retention
time compared to that from an authentic sample of amaraemycolate
isolated from a. laboratory strain of N. amarae. An internal
standard (methyl eicosanoate) injected at the same time, aided in
this comparison. To verify the identity of the putative mycolate-
derived peak, the sample was run again with the injector port at
235 ° C. Under these conditions no pyrolysis of mycolates takes
place; thus, the disappearance of the fatty acid methyl ester peak
confirms its derivation from the pyrolysis of nocardomycolates of
-N. amarae.
The volume under the peak was calculated by multiplying the height
of the peak by its width at half height and the calculation of the
original weight of amarae-mycolate in the starting sample was
calculated as follows:
The volume under the peak of a known amount of methyl vaccenate
(C,gl= ) injected under the same conditions was calculated to give a
peak volume to weight ratio. This, under the conditions of analysis
used was 0.7 nanograms/mm . (A).
The peak volume from the unknown sample (B) was multiplied by (A)
to give the amount by weight in the unknown-sample expressed as
micrograms of C, «1= (G). The total weight of the unknown sample
(C) was divided by the rncl of solvent (D) in •which it was dissolved to
give the concentration of the injected solution in mcg/mcl (E). (E)
was multiplied by the amount (usually 0. 8 mcl) actually injected to
yield the total solids injected (-F). C -r F x G x 3* gave the uncorrected
total of amaraemycolate per 5-gm of dry sludge solids. Corrections
to this last figure were made if the original sample before PTLC
contained more than 50 mg (the maximum purified for GLC analysis).
The methods used in the assay of the mycolates were modified from
those of Lechevalier et al. 1971 and 1973.
Assuming a molecular weight of amaraemycolate of about 900.
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Microscopic monitoring of N, amarae.
The hyphae of Nocardia amarae were also monitored in each
sewage sludge sample by microscopy. Without exception, where
foaming occurred and the amaraemycolate levels were appreciable,
the hyphae of the actinomycete were visible in the samples,, An
actual quantitation of the amount of the nocardia present was
difficult by microscopic means.
The results are shown in Tables 2, 6 and 10.
Testing anaerobic digester supernatant for nocardiotoxicity0
Samples of supernatants from anaerobic digesters to be tested for
nocardiotoxicity were autoclaved for 20 min at 15 Ib/sq. in.
pressure prior to testing. If the samples were received at the end
of the day, they were stored at 4 C overnight prior to sterilization.
Previous experiments showed that autoclaving did not destroy the
toxic substance(s) which is associated with the solids present in the
supernatant (Lechevalier, 1975),
(ATCC 27808).
The test organism was Nocardia amarae Se 6/ It was inoculated in
yeast-extract glucose broth,dispensed at the rate of 50 ml per 250
cc Erlenmeyer flask and was incubated at 28 C on a rotary shaking
machine (New Brunswick Scientific Co. Model G 10) operated at 200
RPM. Yeast-extract glucose medium (YD) is composed of 1% Bacto
yeast extract and 1% glucose in water with-a pH after sterilization of
6.8.
One ml aliquots of the culture of the test organism prepared as
described above were used to inoculate a series of 250 cc flasks
containing 50 ml Czapek's broth (Waksman, 1950) to which 0.2%
yeast extract had been added (YCZ medium). The series of flasks
received 0, 0. 05, 0. 5, 1. 0 an-d 5. 0 ml of the autoclaved anaerobic
digest to be assayed. Assays were run in duplicate.
The assay flasks were incubated for 48 hr as described above at
which time the growth was measured by the packed cell volume
assay method.
The packed cell volume assay consisted in centrifuging 5 ml of each
culture at 1, 200 g for 3 min in graduated conical centrifuge tubes.
10
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The volume of the packed cells was read off directly.
These readings were plotted on arithmetic paper and the 50%
inhibition concentration was determined as mg of anaerobic
supernatant solids per ml of YCz broth required to reduce growth
of No amarae Se 6 to 50% of that found in the untreated control.
To determine the dry weight of the solids per ml of anaerobic
supernatant, 5 ml of well-mixed autoclaved material was placed
into a tared weighing dish and taken to constant weight at 60 C.
11
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SECTION V
SPECTRUM OF ANTIMICROBIAL ACTIVITY OF
ANAEROBIC DIGESTER SUPERNATANT SOLIDS
Before we started this study we knew that the solids present in
anaerobic supernatant were toxic to strains of Nocardia amarae.
We felt that it would be useful to know if this material is also toxic
for fecal bacteria likely to be found in domestic sewage. Using a
modification of the assay method that we used for the determination
of toxicity to N. amarae Se 6, we also tested the sensitivity of
Streptococcus faecalis LL-B, Enterobacter cloacae LL-B and
Escherichia coli 54.
The organisms to be tested were grown in nutrient broth for 24 hr
at 28 °C by shaking at 200 RPM in 250 cc Erlenmeyer flasks contain-
ing 50 cc of medium. These were used to inoculate (2% inoculum)
similar flasks of nutrient broth containing 3. 3, 0. 3 and 0. 03 mg/ml
of supernatant solids (determined as dry weight) from the Middletown
plant sample of 6/10/75). These cultures were incubated as
described above for 24 hr and then centrifuged at 300 G for 1 min to
settle the supernatant solids, leaving the bacteria in suspension.
Bacterial growth was estimated from the optical density of the
bacterial suspensions which were measured with a Klett-Summer son
colorimeter using a No. 66 filter. Control flasks included: a)
nutrient broth containing only bacteria and no supernatant solids and
b) nutrient broth containing only supernatant solids and no bacteria.
Both types of controls were shaken 24 hr at 28 C and centrifuged as
in the case of the experimental flasks.
The results were that at 3. 3 mg/ml the growth of E. cloacae was
reduced to 12% of that found in the positive control cultures and that
of E. coli to 40%. These results were observed after 24 hr
incubation but remained unchanged when the cultures were incubated
for a total of 5 days. In the case of S. faecalis, no inhibition was
* 1.65 mg/ml, of this sample were required to give 50% inhibition of
Nocardia amarae Se 6.
12
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observed.
We can thus conclude that the solids present in anaerobic digester
supernatant are not toxic to the same level for all types of bacteria
and may even be non-toxic for some. These solids thus must play
a selective role in the control of the microbial population of the
activated sludge •when they are returned into the system.
13
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SECTION VI
THE BERNARDSVILLE PLANT
The Bernardsville Waste-water Treatment Plant in the Borough of
Bernardsville, Somerset County, N. J. was constructed in 1933.
When we started our studies in 1971, the 1,893 m3/d (0.5 mgd)
plant consisted of preliminary treatment (comminutor), primary
sedimentation (rectangular clarifier), conventional diffused air
activated sludge treatment with rectangular final settling tanks (with-
out scum baffles), effluent disinfection (chlorination) and anaerobic
digestion (conventional). The digested sludge was dewatered by
centrifugation and the anaerobic supernatant was returned to the
primary treatment system. Dewatered sludge was used for landfill.
As far back as the operators of the plant could recall the
Bernardsville facility had been free of heavy foaming and we were
unable to see or isolate nocardia from the Bernardsville suspended
solids during the period of April 1971 to May 1974.
Later in 1974, the Bernardsville plant was modified in such a way
that the anaerobic digester was no longer used. In spring 1975, the
aeration tanks of the plant were covered with a thick foam in which
actinomycetic hyphae could be seen and a number of strains of
N. amarae and N. rhodochrous were isolated from it. We thought
that the Bernardsville facilities would be ideal for the testing of our
hypothesis because it was a plant which had operated for a long time
without nocardial foam and which had started to foam only after the
anaerobic digesters had been abandoned.
We asked the operator of the plant to reactivate the anaerobic
digesters in order to be able to return their supernatant into the
system, as it was done previously. During the period of this study
(May 1975 to May 1976) he was unable to get satisfactory digestion,
the pH remaining always on the acidic side (pH 4 to 5). We
eventually had to abandon the hope of being able to use this plant for
this study.
14
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SECTION VII
THE FLORHAM PARK PLANT
The Florham Park Sewage treatment plant located in the Borough of
Florham Park, Morris County, New Jersey was constructed in
December 1966. The plant has a capacity of 3, 785 m3/d (1.0 mgd)
and consists of preliminary treatment (comminutor and grit
remover), rectangular primary sedimentation tanks with scum and
sludge conveyed to the digesters, conventional secondary activated
sludge (diffused air) and secondary sedimentation in rectangular
units, effluent disinfection (chlorination); digested sludge is dewatered
by vacuum filtration and disposed as land fill. The anaerobic super-
natant is returned to the preliminary treatment units as illustrated in
the flow diagram (Figure 1). The foam and scum collected on the
surface of the secondary clarifiers is periodically manually removed
and disposed as landfill.
At the beginning of our study, as can be seen in Table 1, the plant had
little or no foam accumulation. Toward the end of June the foam and
scum, which was shown to contain nocardias (Table 2) and from which
strains of N. amarae were isolated, was sufficiently developed to
attempt control by the return of digester supernatant, the solids of
which were toxic to Nocardia amarae (Table 3). Plant operating
records during the study period are given in Table 4. Figure 2 gives
the nocardiotoxicity of the supernatant solids and the nocardiomycolate
levels of the sludge solids.
On July 1, a control program was instituted consisting of the return
of approximately 6. 4 m (1, 700 gal) of anaerobic digester supernatant
per day to the plant headworks. This quantity of return represented
about a ratio of 1 volume of supernatant to 500 of plant flow and was
based on a preliminary experiment run at the Middletown plant in
1974. The supernatant was returned to the primary flowstream over
an average 4 hr time period.
15
-------
Waste Sludge
Primary
Settling
Tanks
Return Activated Sludge
Grit
Remover
Pumps
Wet Well
Comminutor
Influent
Aeration
Tanks
Final
Settling
Tanks
(A> Pumps
I Sludge
^—tt>—» - - J
Digesters
Chlorine
Contact
Tanks
Effluent
Vacuum
Filter
FLOW DIAGRAM
SEWAGE TREATMENT PLANT
FLORHAM PARK SEWERAGE AUTHORITY
Figure 1
-------
Table 1. FIELD OBSERVATIONS
FLORHAM PARK PLANT
Date
May 6, 1975
12
20
27
June 2, 1975
10
17
24
Aeration
tanks
Darkish
Some
foam
Some
foam
Some
foam
Some
foam
Low foam
Some
foam
Good
foam
developmen'
Final
settling
tanks
Normal.
Some
channel
scum
Some
channel
scum
More
channel
scum
Some
channel
scum
More
channel
scum
Low
channel
scum
Some
channel
scum
Good
scum
t amount in
Activated
sludge
Color dark
Color dark
Color
darkish
Color
darkish
Color
dark
Color
dark
Color
good
darkish
Color
good
darkish
Scum/
foam
conditions
Low amount
Low amount
Low amount
Low amount
Medium
amount
Low amount
Low amount
Good
development
Miscellaneous
observations
and
r ecommendatio ns
To keep super.
natant return to a
minimum
To try to lower
RAS rate
Reducing RAS rate
Returned large
amount of supernata*
RAS valve
problem
Temperature of
sewage 17* C
Foam in primary
channel too
channel
17
-------
Table 1 (continued). FIELD OBSERVATIONS
FLORHAM PARK PLANT
Date Aeration
tanks
July 1, 1975 Plenty of
foam
8 Somewhat
leas foam
15 Less foam
22 Good foam-
ing
29 Good foam
August 1, 1975 Less foam
12 Plenty
foam
19 Plenty
foam
26 Less foam
Final
settling
tanks
Plenty of
scum in
channel
bulking
Less scum
in channels
Less scum
dark color
Good scum
in channels
Good scum
in channels
Less scum
in channels
Plenty
channel
scum
Plenty
scum in
channel
Leas
scum in
channel
Activated
sludge
Color dark
Color dark
Very dark
color
Color dark
Color very
dark
Color good
Color dark
Color dark
Color dark
Scum/
foam
conditions
Good
development
Somewhat
reduced
Reduced
Good
development
Good
development
Reduced
Good
development
Good
development
Reduced
Miscellaneous
observations
and
recommendations
Started super*
aatant control: 10.2
cm/day (4"/day)RAS
problem and
wasting problem
ML highrwasiing
problem; supernatant
return cut to 7. 6
cm/day (3"/day)
Rain; heavy flow
washed out ML
ML washed out
due to heavy rain
flows
ML high; wasting
problem
Wasting problem
By pass out;l final
out; wasting problem
Heavy rain; ML
washed out; flow
change wasting
18
-------
Table 1 (continued). FIELD OBSERVATIONS
FLORHAM PARK PLANT
Date
August 27, 1975
Sept. 2
4
9.
Aeration
tanks
Less foam
Plenty of
foam
Plenty of -
foam
Plenty of
foam
Final Activated
settling sludge
tanks
Less scum; Color dark
very good
clarity
Plenty of Color dark*
foam in ish
channel;
good
clarity
Clarity Color dark
good;
plenty of
scum
Plenty of Color dark
scum in
channels
Scum/
foam
conditions
Reduced
Good
development
Good
development
Good
development
Miscellaneous
observations
and
recommendations
Started new-
wasting
ML 1800 ± mg/l
Supernatant from
primary dig es tor
Wasting problem
Go back to
secondary digestoi
supernatant
12
16
23
Plenty of
foam
Some
foam
Lot of
light scum
in channels
Lot of scum
in channel,
little in
primary
channel;
#1 bulking
Dark color
Dark color
Good
development
Good
development
Less foaming
during day, more
at night
Will lower
aeration at night;
wasting problem
Heavy rain last
night; wasting
problem
19
-------
Table 1 (continued). FIELD OBSERVATIONS
FLORHAM PARK PLANT
Date
Aeration
tanks
Final
settling
tanks
Activated
sludge
Scum/
foam
conditions
Miscellaneous
observations
and
recommendations
Sept. 30, 1975 Less foam
Good scum
in channel
Color very
dark
Reduced?
Heavy rain and
flow washed out
ML; changing RAS
well
Oct. 7
14
Lots of
foam
Less foam
21
Some foam
28
31
Less foam
Some foam
Plenty of Color very-
scum in dark
channels
Somewhat Color very
less scum; dark
tanks bulk-
ing; clarity
poor
More scum Color
in channels; better but
good still dark-
clarity; #1 ish
some bulking
Good
development
Reduced
Less scum
in channel;
bulking in
afternoon
Some scum
in channels
f 1 bulking
Color good
darkish
Color very
good
Increasing
development
Reduced?
Reduced
(same as
28th)
Change RAS
method
RAS clogged 12
and 13th.
Problems with
wasting and RAS.
Stoppe'd super-
natant control on
10th
Will keep no
supernatant feed
until next week,
then drop slug
amount
To drop slug of
supernatant
25.4 cm (10")
20
-------
Table 1 (continued). FIELD OBSERVATIONS
FLORHAM PARK PLANT
Date Aeration Final Activated Scum/
tanks settling sludge foam
tanks conditions
Miscellaneous
observations
and
recommendations
Nov. 4, 1975
Lots of dark Lots of dark Color very
foam scum dark
#1 bulking
10
18
25
Dec. 2
Less foam
Plenty of
foam
Increased
development
Less foam
Plenty of
foam
Somewhat
less foam
Slightly
less scum
#1 bulking
Plenty of
scum in
channels
but lighter
than in
past
Somewhat
less scum
Color good,
darkish
Color
darkish
Color good
Reduced
Increased
development
Plenty of
scum in
channels
Color
darkish
Plenty of Color
foam in darkish
channels;
#2 bulking
About same
as 10th
Increased
development
Good
development
Dropped 99 cm
(3 ft. 3 inches)
of digester on
31st. Much
problems with
clogging pumps
and etc.
Wasting problems
Dropped 30. 5 cm
(12") of super-
natant wasting
problem
Wasting problem
End control
attempts
HAS = activated sludge return.
ML = mixed liquor of aeration tanks.
21
-------
Table 20 ANALYSIS OF RETURN ACTIVATED SLUDGE
FLORHAM PARK PLANT
Date
5-6-75
5-12
5-20
5-27
6-2
6-10
6-17
6-24
7-1
7-8
7-15
7-22
7-29
8-1
8-12
8-19
8*26
Suspended
solids
mg/1
6,400
7,200
6,600
8,800
8,200
14,400
10,600
10,600
8,400
9,000
9,000
8,400
8,200
8,000
9,600
4,200
9,800
Microscopic Mycolate content
estimation of M-g/5 gm dry
nocardial hyphae sludge solids
+ 6.3
+ — 34.2
+ — 30.9
-f- 199
+ 188
+ 141
+ 130
+ 286
-f 453
+ 433
+ 142
+ 153
+ 281
+ 444
+ 575
+ 391
+ 481
22
-------
Table 2 (continued),, ANALYSIS OF RETURN ACTIVATED SLUDGE
FLORHAM PARK PLANT
Date
9-2-75
9-9
9-16
9*23
9*30
10-7
10*14
10*21
10-28
11*4
11*10
11-18
11*25
Suspended
solids
mg/1
7,200
7,200
7,800
8,800
9,200
11,600
10,600
8,400
8,000
9,800
8,800
9,280
6,800
Microscopic Mycolate content
estimation of H*g/5 gm dry
nocardial hyphae sludge solids
+ 310
+ 570
+ 402
-1- 418
+ 242
+ 1,169
+ 353
+ 413
•f 1,051
+ 623
23
-------
Table 30 ANALYSIS OF DIGESTER SUPERNATANT
FLORHAM PARK PLANT
Date
6-24-75
7/1-8
7/9-14
7/15-21
7/22-29
7/30-8/12
8/13-19
8/20-26
8/27-9/2
9/3-9
9/10-16
9/17-23
9/24-30
10/1-7
10/8-14
10/31
11/18
Suspended
solids
mg/1
15,300
22,400
16, 100
20, 800
26,000
10,600
8, 300
4,500
3,900
12,600
25, 700
20,400
24, 300
33, 700
28, 100
13,800
8,500
nag /ml for
50% inhibition
of N. amarae
U2
1.1
1.3
1. 1
Oo7
0.8
2.7
>3.0
0.9
1.3
0.9
1.1
1.1
0.4
Av. 1.3
24
-------
Table 4. PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
FLORHAM PARK PLANT
Flow
Date
5/1-6
1-13
14-20
21-27
28-6/3
4-10
11-17
18-24
25-30
7/1-8
9-14
x icr
2.80
2.89
2.98
2.66
2.75
2.98
3.09
2.71
2.49
2.41
3.25
M. G.D.
(.740)
(.763)
(. 788)
(.703)
{. 72?)
(. 787)
(.816)
(.716)
(.659)
(.636)
(.858)
Sew, Temp. pH
Infl.
•c
13
14
15
16
16
17
17
18
18
19
19
Infl.
7.9
7.6
7.8
7.9
7.8
7.8
7.5
7.6
7.7
7.6
7.6
Effl.
7.1
7. 1
7. 1
7.0
7.1
7. 1
7.1
7. 1
7.0
7.1
6.9
Suspended Solids
Infl.
mg/1
160
143
125
146
210
180
155
135
160
180
165
Effl.
mg/1
40
6
20
21
11
19
15
10
9
25
30
REM.
75
96
84
86
95
89
90
93
95
86
82
BOD/5
Infl. Pri. effl.
mg/1 mg/1
140
320
145
130
137
140
160
250
130
150
130
, Effl.
mg/1
16
11
12
5
5
5
10
8
8
30
22
REM.
89
97
92
96
96
96
94
97
94
80
83
-------
Table 4 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
FLORHAM PARK PLANT
N)
Flow
Sew. Temp.
Suspended Solids
BOD/5
Date
15/21
22-29
30 8/12
13-19
20-26
27-9/2
3-9
10-16
17-23
24-30
10/1-7
m3/d
x 103
3.12
2.78
2.39
2.15
2.82
2.46
2.43
2.38
2.85
4.78
2.71
M. G. D.
(.823)
(. 736)
(.631)
(.568)
(. 745)
(.650)
(.641)
(.629)
(. 752)
(1.264)
(.716)
Infl.
°C
20
20
20
21
21
21
20
20
20
19
19
Infl.
7.2
7.4
7.4
7.6
7.5
7.6
7.8
7.7
7.8
7.6
7.7
Effl.
6.9
7.0
7.0
7.0
6.8
6.8
7.0
7.0
7.2
7. 1
7. 1
Infl.
mg/1
120
130
175
120
170
130
140
140
130
-
110
Effl.
mg/l
13
21
10
16
20
15
10
15
5
-
12
%
REM.
89
84
94
87
88
88 •
93
89
96
89
Infl. Pri. efft.
mg/l mg/l
130
115
125
140
150
120
170
120
150
-
130
Effl.
mg/l
20
20
10
15
8
13
5
7
10
-
14
%
REM.
85
83
92
89
95
89
97
94
93
89
-------
Table 4 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
FLORHAM PARK PLANT
Flow Sew. Temp.
Date
8-14
15-21
22-28
m3/d
x 103
2.64
3.30
2.81
29-11/4 2.65
5-10
11-18
19-25
2.79
2.83
2.82
26-12/2 2.66
Sew =
Infl =
Effl =
Sewage
Influent
Effluent
M. G. D.
(.697)
(.873)
(. 743)
(.699)
(.738)
(. 749)
(. 745)
(.703)
Infl.
•c
19
19
18
18
18
17
17
16
REM =
BOD/5
PH
Infl.
7.8
7.7
7.6
7.8
7.8
7.8
7.8
8.0
Effl.
7. 1
7.0
7.0
7.0
7.1
6.9
6.9
7.0
Suspended Solids
Infl.
mg/l
145
145
112
170
165
120
138
-
Effl.
mg/l
15
15
12
12
15
25
13
-
REM.
90
90
89
93
91
79
91
-
BOD/5
Infl. Pri. effl.
mg/l mg/l
180
170
156
120
150
130
147
-
Effl.
mg/l
15
5
8
16
8
12
8
-
REM.
87
97
95
87
95
91
95
-
removal
= 5 day
biochemical oxygen demand
-------
10
oo
TABLE 4 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
FLORHAM PARK PLANT
Aeration
Date
5/1*6
7*13
14-20
21-27
28-6/3
4*10
11-17
18*24
25-30
7/1*8
9-14
MLSS
mg/1
2150
2371
2643
2100
2129
2157
2486
2757
2567
3175
2750
ML
Set S
ml /I
520
470
440
250
240
220
240
280
290
340
320
Tanks
SVI
245
194
156
116
111
104
98
100
110
104
117
DO
mg/1
2.6
2.7
2.6
3.2
3.5
3.0
3.1
2,9
2.5
2.2
1.7
Ret, sludge
% SS
R mg/1
t
| |
0 -H
g
O ?-i
vO
£ !
•1-1 f-\
CO
H
1
Digesters
Sup'n Misc.
Gal % TS
9690
3960
7490 .2
S
JH
4840 £
-------
TABLE 4 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
FLORHAM PARK PLANT
Aeration
Date
15*21
22-29
30*8/12
13*19
20-26
27*7/2
3*9
10*16
17-23
24*30
10/1-7
MLSS
mg/1
2488
2963
3464
3385
2757
2850
2657
2671
3000
2100
2986
ML
Set S
ml/1
220
310
370
310
270
290
250
340
370
180
290
Tanks
SVI
91
102
104
94
93
95
94
124
129
91
94
DO
mg/1
2.2
2.0
2.0
2.0
2.1
2.1
2.0
2.1
2.0
2.2
2.2
Ret. sludge
% SS
R mg/1
t
£5.
° T)
0 a,
•-1 C!
ft *!"j
* g
s «
rtf V
0) P
"rt •£
1 %
'**
ID
W
1
Digesters
Sup'n Misc.
Gal % TS
11010
18500
9250
9250
T)
(1)
9250 .§
a
)H
9250 5
-------
TABLE 4 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
FLORHAM PARK PLANT
Aeration
Date
8*14
15*21
22-28
29-H/4
5-10
11-18
19-25
26-12/2
MLSS
mg/1
2564
2244
2616
2767
2883
3031
2586
2217
ML
Set S
ml/1
270
270
310
320
320
360
340
310
Tanks
SVI
97
103
112
111
113
114
114
136
Ret. sludge Digesters
% SS Sup'n Misc.
DO R mg/1 Gal % TS
mg/1
2, 3 3960 No super
10th-*
2.4 0
2-1 "g 0 -g
t H -H
2.3 -H 'S 17170 |
2.4 1 Q ° p
^ ±> +>
2.9 g 5280 |
2.4
2.2
MLSS = Mixed Liquor Suspended Solids
ML Set S = Mixed Liquor Settleable Solids
SVI = Sludge Volume Index
DO = Dissolved Oxygen
SS = Suspended Solids
Sup'n. = Supernatant
TS = Total Solids
-------
Florham Park, July to October 1975
Supernatant Toxicity and Mycolate liters
O
to
o
o>
0)
o
o
E
o
.0
'^.
o
"o
in
o
c
0)
0.
o
1
o>
s
O
5.0
4.0
3.0
2.0
1.0
7/1-7/8 | 7/5-7/21 | 8/1 | 8/27 | 9/9
7/9-7/14 7/22-7/29 8/18 9/2
1000
900
800
700
600
500
400
300
200
00
v>
o
in
Q)
en
•O
_=>
tn
>,
9)
O
"O
O
>>
E
0)
o
O
o
9/17
9/22 | 9/30MO/6 |
9/23-9/29 10/7*10/13
Figure 2. Nocardiotoxicity of the Supernatant from the Anaerobic Digester and
Nocardiomycolate Contents of Sludge Solids at the Florham Park Plant
from July 1 to October 13, 1975
-------
Throughout the study period, the return of anaerobic supernatant
did not appear to affect the development of actinomycetic foam.
Periodically, the foam was reduced but it was not clear if this
effect was not due to excessive flow and the washout of aeration
tanks due to infiltration or inflow from occasional heavy rainfalls.
An additional source of problems were the many operational
difficulties the Florham Park plant experienced throughout the study
period.
Two major problems were the control of the return activated sludge
system and the removal of excessive activated sludge from the
process to maintain a proper concentration of suspended solids under
aeration.
Throughout the study period, it was felt that the mixed liquor
suspended solids content in the aeration system was too high for the
attempted control to be effective. Although a comparison of the
data on suspended solids in Table 4 does not show high solid contents,
the high aeration solids retention time or "sludge age" at this plant
(Table 13) shows that the concentration of suspended solids in the
aeration tanks was about twice that in the two other plants studied.
Various attempts at revision of the plant system were made to permit
a proper control of the wasting from the aeration system but none were
successful in reducing the excess level of mixed liquor suspended
solids under aeration.
On the 10th of October the daily return of supernatant was discontinued
and instead, a control method of returning large amounts of super-
natant (17 m.3/d = 4500 gal/d) to the system at selected intervals was
instituted. This was referred to as "slugging" the system. The
reasoning behind this procedure was that the nocardial population
might have become adapted to the presence of small amounts of toxic
material. It was felt that the periodic slugging of the system with
larger doses might be more beneficial. The results, as indicated in
Table 1, did not show any significant reduction in foaming. In fact,
the first attempt at slugging the system resulted in an upset of the
plant system because of the accidental addition of too large a volume
(65 m3 = 17, 170 gal). The second attempt at slugging the system was
better controlled and did not affect the plant system; however, no
significant reduction of the foam or scum formation was noted.
32
-------
Since the addition of anaerobic supernatant had no apparent effect on
the actinomycetic foam at Florham Park, the question was asked if
this was due to an increase in resistance of the nocardial flora of
the sludge. In order to answer this question, the foam was plated
out as previously described (L/echevalier, 1975) and two strains of
Nocardia amarae were isolated (strains Se 351 and Se 355). These
were tested for sensitivity to anaerobic digester supernatant solids
as previously described at the same time as our standard assay
strain Se 6. The freshly isolated strains turned out to be more
sensitive to the supernatant solids than our assay strain. Their
growth was inhibited 50% by 1. 8 mg of solids per ml as compared to
4. 9 mg/ml in the case of Se 6. It was then concluded that the lack
of control of the foam was not due to an increase of resistance of the
nocardial population.
33
-------
SECTION VIII
THE MIDDLETOWN PLANT
The Middletown Waste treatment plant began operation in July, 1971.
It is a 24, 600 m /d (6. 5 mgd) facility which provides for preliminary
treatment (mechanical bar screen and grid remover); primary treat-
ment in rectangular clarifiers with the sludge and scum sent to
anaerobic digesters; secondary treatment of the conventional
activated sludge type with aeration by mechanical turbines; circular
final clarifiers in which the wasted sludge and collected surface scum
are sent to the anaerobic digesters; effluent chlorination and
anaerobic sludge digestion. Digested sludge is disposed by barging
to an ocean disposal site. The supernatant from the anaerobic digestion
system is returned to the primary treatment facilities at the wet well
(see flow diagram, Figure 3).
As can be seen in Table 5, supernatant return was kept to a minimum
and good development of foam was noted starting July 15. On July 28,
a control program consisting in returning approximately 6 inches
(15. 2 cm = 12,400 gal) of anaerobic supernatant per day to the
primary flow stream was instituted (Table 5). This amount of super-
natant was returned in approximately 1/2 h. It was felt that this rapid
procedure would minimize removal of supernatant solids in the
primary sedimentation units. By the end of August, the reduction in
foaming was obvious and reached a low level on September 30. At
this point it was felt that the control method had succeeded and that the
foam nuisance was eliminated. Throughout the remaining portion of
the study period, an increase in the actinomycetic foam was noted at
the plant which was attributed to the variation in supernatant control
feeding, a decrease in the supernatant toxicity (Table 7), and
difficulties with various plant units.
34
-------
Final
Settling
Tanks
Chlorine
Contact
Tanks
Aeration
Tanks
0)
fd
A
w P
M rH
fd fe
0<
Primary
Settling
Tanks
"S« 1
J '
1
t
Grit
Remover
Pumps
Floatation
Thickener
Digesters
Effluent
c()>Pumps
"sludge
*
I
I
-*-,
+ --
Supernatant
^ ^ ^o^ I
/ Sludge to Barge ^Pumps
/
FLOW DIAGRAM
SEWAGE TREATfTCNT PLANT
TOWNSHIP OF MIDDLETOWN SEWERAGE AUTHORITY
/
Figure 3
-------
TableS. FIELD OBSERVATIONS
MIDDLETOWN PLANT
Date
May 5, 75
13
21
27
June 2
10
19
24
Aeration
tanks
Normal
Normal
Normal
Normal
Some
foam
Normal
Moderate
foam
Minor
foam
Final
settling
tanks
Normal
Minor
scum
Some
scum on
#2
Very
slight
scum
Some
scum
Some
scum
Scum on
#2
slight on
#1
Normal
Activated Scum/
sludge foam
condition
None
Color good
Minor
Color good Minor
Color good Slight
Color good Minor
Color good Slight
Color good Minor
but darkish
Miscellaneous
To keep supernatant
return to minimum
Sewage temperature
14. 5 • C
Sewage temperature
17"C
Dropped back 61 cm (21) of
digester #2
Barged sludge
Sewage temperature
20 °C
Dropped back some
digester #2
36
-------
TableS (continued). FIELD OBSERVATIONS
MIDDLETOWN PLANT
Date
July 1, 75
8
15
22
29
Aug. 1
12
Aeration
tanks
Normal
Normal
Full of
foam
Foaming
Foaming
Foaming
Good
foam
develop-
ment
Final
settling
tanks
Minor
scum
Some
scum
Lot of
scum
Lot of
scum
Lot of
scum
Lot of
scum
loss in
center
well
Good
scum
layer
Activated Scum/
sludge foam Miscellaneous
condition
Color good Minor
Color good Minor
but darkish
Good color Good
development
Good color Good Sewage temperature
development 21°C
Good color Good Started supernatant
development control 7/28 /7C
15.2 cm (6")/day
Good color Good
somewhat development
dark
Good color Good Stopped supernatant
but dark development control but will re-
start
No supernatant 9,
10, 11 and 12
37
-------
TableS (continued). FIELD OBSERVATIONS
MIDDLETOWN PLANT
Date
Aug. 19, 75
26
Sept. 2
9
16
Aeration
tanks
Less
foam
Some
foam
Lots of
Light
froth
foam
Lots of
light
foam
Good
foam
Final
settling
tanks
Less
foam
Less
scum
Some
scum
None in
center-
wells
Very-
little
to no
scum
Very
light
scum.
Some
in
center-
wells.
Activated
sludge
Color good
slightly
dark
Color good
darkish
Normal
Color
good
Normal
Scum/
foam
condition
Somewhat
reduced
Reduced
Reduced
Reduced
to low
level
Reduced
Miscellaneous
Restarted control
on August 14 7. 6 cm
(3") /day
No supernatant 23
and 24
Detergent spill August
29? Increase super-
natant to 15.4 cm (6">/day.
No supernatant 30, 31
and 1.
Primary down Sunday.
No supernatant 3 and 7.
Barged sludge.
No supernatant 10, 12,
13, 14, and 15th.
38
-------
Table 5 (continued). FIELD OBSERVATIONS
MIDDLETOWN PLANT
Aeration
Date tanks
Sept. 23, 75 Less
foam
30 No
foam
Oct. 7 No
foam
14 Some
minor
foam
21 Some
foam
darkish
Final
settling
tanks
Very
little
scum.
Minor
in
center-
wells.
Minor
scum
particles
Minor
scum
particles.
None in
centerwell
Minor
scum.
None in
center-
well.
Very
little
scum.
None in
center-
wells.
Activated Scum/
sludge foam
condition
Good color Reduced
Color very Very low
dark level -
minor
Color good None
darkish
Color good Minor
Color Low
darkish - level
heavy
Miscellaneous
No supernatant 17,
18 and 20.
Problem with 1
primary
Primary down on 30th,
No supernatant 30 and
1st. Barged sludge.
No supernatant 11, 12
and 13th
1 Final tank down and
recycle low.
39
-------
Table 5 (continued). FIELD OBSERVATIONS
MIDDLETOWN PLANT
Aeration
Date tanks
Oct. 28, 75 Some
foam.
Light
color
Nov. 4 Foaming
10 Heavy
foam
18 Good
foam
develop-
ment
25 Lots of
foam.
MLSS
Final Activated Scum/
settling sludge foam Miscellaneous
tanks condition
Good Good coloi; Moderate No supernatant 24,
scum. light development 25, and 27th
1/3 of
tank and
center-
well.
Minor Good color Reduced No supernatant 1 and
scum 2nd
Some Good color, Moderate,
scum. dark increased
1/4 tank;
heavy in
center-
well.
Some Good color Reduced No supernatant 17 am
scum to dark 18? Barged on 13th.
minor
good in
center-
well.
Looks
like
breaking
up.
Lots of Darkish Increased? Recycle was off som<
dark time. May be reasoi
scum for scum in finals.
very
low
End control attempts.
40
-------
Table 6. ANALYSIS OF RETURN ACTIVATED SLUDGE
MIDDLETOWN PLANT
Date
5-5-75
5*13
5-21
5-27
6-2
6-10
6-19
6-24
7-1
7-8
7-15
7-22
7-28
7-29
8-1
8-12
8-19
Suspended
solids
mg/1
4,400
7,800
8,800
8,000
8,800
11,000
9,200
10,600
12,000
15, 200
9,800
11,400
14,600
8,600
9,600
13,200
1 1, 200
Microscopic Mycolate content
estimation of F^g/S gm dry
nocardial hyphae sludge solids
0
0
3
+ — 0
+ — 12
+ „ 11
+ — 10
0
-f 23.7
+ 46
+ 34
+ 57
+ 81
+ 88
+ 85
41
-------
Table 6 (continued). ANALYSIS OF RETURN ACTIVATED SLUDGE
MIDDLETOWN PLANT
Date
8-26
9-2
9-9
9-16
9-23
9-30
10-7
10-14
10-21
10-28
11-4
11-10
11*18
11-25
Suspended
solids
mg/1
8,200
8,400
9,000
8,400
11,600
8,800
9,000
11,400
12, 800
8,800
13,200
13, 200
12, 000
15, 800
Microscopic Mycolate content
estimation of H-g/5 gm dry
nocardial hyphae sludge solids
+ 47
+ 78
-j- . 202
+ 103
+ 33
+ 29
+ 26
+ 45
+ 73
+ 150
+ 186
42
-------
Table 7. ANALYSIS OF DIGESTER SUPERNATANT
MIDDLETOWN PLANT
Date
7/15-21
7/30-8/12
8/13-19
8/20-26
8/27-9/2
9/3-9/9
9/10-16
9/17-23
9/24-30
10/1-7
10/8-14
10/15-21
10/22-28
10/29-H/4
11/5-10
11/11-18
11/19-25
Suspended
solids
mg/1
29,900
34, 000
36,800
37,000
33,900
34,500
36,500
13,200
23,600
36, 100
23,000
28,000
26,000
32,500
30, 100
33,200
20, 100
mg/ml for
50% inhibition
of N. amarae
1.6
1.4
2.5
2.3
2.9
4.9
2.5
1.5
0.9
1. 1
3.7
4.4
1.8
2. 0
1.6
1.9
Av. 2.3
43
-------
Table 8. PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
MIDDLETOWN PLANT
Flow Sew. Temp.
Date
5/1-6
7-13
14-20
21-27
28-6/3
4-10
11-17
18-24
25-30
7/1-8
9-14
m3/d
x 103
17.75
18.96
18.77
17.83
17.98
17.98
18.85
19.30
17.52
17. 18
18.58
M.G.D.
(4.69)
(5.01)
(4.96)
(4.71)
(4. 75)
(4. 75)
(4.98)
(5. 10)
(4.63)
(4. 54)
(4.91)
Infl.
°C
13.6
14.6
16.1
16.3
16.9
16.8
17.4
17.9
18.6
19
19
PH
Inn.
7.1
7. 1
7.1
7.1
7.2
7. 1
7.2
7.2
7.2
7.1
7. 1
Effl.
7.1
7.2
7.0
7.2
7.2
7.2
7. 1
7.0
6.9
6.8
6.8
Suspended Solids
Infl.
mg/1
144
169
202
141
164
149
138
163
199
190
167
Effl.
mg/1
13
6
10
16
7
13
10
18
13
15
17
REM.
91
96
95
87
96
91
93
89 '
93
92
90
BOD/5
Infl. Pri. effl.
mg/l mg/1
175
181 138
160
166
150
178
151
220
-
146
173 128
Effl.
mg/1
7
9
10
8
5
13
5
7
-
8
7
REM.
96
95
94
95
97
93
97
97,
95
96
-------
Table 8 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
MIDDLETOWN PLANT
Flow Sew. Temp.
Date
15-21
22-29
30-8/12
13-19
20-26
27-7/2
3-9
10-16
17-23
24-30
m3/d
x 103
19.38
19.30
17.90
18.21
18.36
18.05
17.45
17.41
17.22
20.74
M. G.D.
(5.12)
(5.10)
(4. 73)
(4.81)
(4. 85)
(4. 77)
(4.61)
(4. 60)
(4.55)
(5.48)
Infl.
*C
20.0
20.8
21
20.9
20.7
20.4
20.0
19.1
19
18.6
PH
Infl.
7.2
7.3
7. 1
7.2
7.2
7. 1
7. 1
7. 1
7. 1
7. 1
Effl.
6.8
6.8
6.8
6.8
6.8
6.8
6.9
6.7
6.7
6.8
Suspended Solids
Infl.
mg/l
205
206
173
237
213
190
218
152
152
150
Effl.
mg/l
23
22
19
41
14
38
76
38
14
16
REM.
89
89
89
83
93
80
65
75
91
89
BOD/5
Infl. Pri. effl.
mg/l mg/l
177 147
191 143
140 140
169
150
160 231
137
177
183
188
Effl.
mg/l
12
14
6
46
4
14
33
51
11
25
REM.
93
93
96
73
97
91
76
71
94
87
-------
Table 8 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
MIDDLETOWN PLANT
Flow Sew. Temp.
Date
10/1-7
8-14
15-21
22-Z8
m3/d
x 103
19.98
19.11
19.38
19.98
29-11/4 18.74
5-10
11-18
19-25
18.66
18.36
18.81
26-12/2 19.91
Sew =
Infl =
Effl =
Sewage
Influent
Effluent
M.G.D.
(5.28)
(5.05)
(5.12)
(5. 28)
(4. 95)
(4.93)
(4.85)
(4.97)
(5.26)
Infl.
•c
19
18
18.5
18
17.5
18
18
18
17
REM =
BOD/5
pH
Infl.
7. 1
7.0
7.0
7.0
7.0
7. 1
Effl.
6.9
6.9
6.5
6.8
6.8
6.9
Suspended Solids
Infl.
mg/1
112
160
137
151
117
165
133
142
194
Effl.
mg/1
12
14
14
15
11
12
48
17
43
%
REM.
89
91
90
89
91
93
64
88
78
BOD/5
Infl. Pri. effl.
mg/1 mg/1
180
182
186
179
178
221
166
194
198
Effl.
mg/1
35
14
11
17
7
10
10
12
56
%
REM.
81
92
94
91
96
95
94
94
72
Removal
= 5 day Biochemical Oxygen Demand
-------
Table 8 (continued). PLANT OPERA TING'RECOKoo
(WEEKLY AVERAGES)
MIDDLETOWN PLANT
Aeration
Date
5/1-6
7*13
14*20
21*27
28-6/3
4*10
11-17
18-24
25-30
MLSS
mg/1
2173
2345
2238
2644
2220
2239
2600
2508
2730
ML
Set S.
ml/1
240
340
310
430
300
400
370
270
370
Tanks
SVI
110
143
136
163
135
175
141
108
136
DO
mg/1
Recorded
0
Ret.
R
39
44
41
40
40
42
41
42
41
sludge Digesters
SS Sup'n
mg/l Gal % TS
8283
7530
8027
8355
7985 49,600
8615
9956
9034
9115
-------
*>.
00
Table 8 (continued), PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
MIDDLETOWN PLANT
Date
7/1-8
9-14
15-21
22*29
30-8/12
13-19
20*26
27*9/2
3-9
10-16
MLSS
mg/1
2846
3526
3164
3114"
2912
3682
2987
2813
2839
2831
Aeration
ML
Set S
ml/1
340
540
430
390
440
660
440
560
700
650
Tanks
SVI
117
151
134
122
144
177
145
201
243
220
Ret. sludge
DO R
mg/1
36
49
44
1 45
o 44
2 42
o
40
40
38
45
SS
mg/1
10,555
11,885
9,627
10,003
10,830
12, 115
9,773
8,540
9, 156
8,486
Digesters
Sup
Gal
' 74,460
200,000
24, 820
33,090
33,090
82, 120
24, 820
•n
% TS
3.4
3.15
1.52
-------
Table 8 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
MIDDLETOWN PLANT
Aeration
Date
17-23
24.30
10/1-7
8-14
15-21
22-28
29-11/4
8-10
11.18
19-25
26-12/2
MLSS
mg/1
2259
2252
2184
2312
1782
2824
2114
2237
2731
2299
2673
ML
SetS
ml/l
570
500
360
520
340
570
360
380
580
510
-
Tanks
SVI
244
210
161
210
179
195
161
164
202
203
-
DO
mg/1
I Recorded
o
2
Ret.
R
31
30
31
30
21
32
28
28
34
36
32
sludge
SS
mg/1
10,337
9,482
9,257
7, 171
7,996
8,640
7,622
8,432
9,639
12,401
8,810
Digesters
Sup1
Gal
62,050
74, 460
86,250
39,300
62,050
49,640
68,260
78,600
82, 180
62,050
n
% TS
2.01
2.22
See legend at end of Table 4.
-------
in
O
10.0
9.0
8.0
7.0
6.0
IE 5.0
c
o
w 4.0
3.0
o
V)
c
o
•*—
o
fc 20
CL
H-
o
1
o>
Middletown, June to November 1975
Supernatant Toxicity and Mycolate liters
900
800 ^
o
a>
700
600
E
o>
500 «
400
o
o
300 t:
o
£
a
200 en
o
100
6/10 I 8/8 | 8/27 | 9/9 | 9/23 |IO/2»IO/5| 10/8 | 10/14 | 10/17 | 10/20 | 10/22 | 10/26 | 10/31
7/22 8/18 9/2 9/16 9/29 10/7*10/10 10/10 10/16 10/18 10/21 10/23 10/29 11/3
Figure 4. Nocardiotoxicity of the Supernatant from the Anaerobic Digester
and Nocardiomycolate Contents of Sludge Solids at the Middletown
Township Plant from June 10 to November 3, 1976.
-------
SECTION IX
THE OCEAN TOWNSHIP PLANT
The Ocean Township Waste-water Treatment Plant began operation
in October 1968. The 11, 355 m3/d (3. 1 mgd) facility consists in
preliminary treatment (comminutor and grit remover) with addition
of hydrogen peroxide; primary treatment in rectangular clarifiers,
the sludge and the scum being disposed of in anaerobic digesters;
secondary treatment of the activated sludge type (sludge reaeration-
contact stabilization), with mechanical turbine aeration; circular
final clarifiers with waste sludge disposal to the primary clarifiers
and the secondary scum being returned to the sludge reaeration
tanks; effluent chlorination and anaerobic sludge digestion. The
supernatant from the anaerobic digesters is returned to the primary
system at the wet well after having been chlorinated by Purifax
treatment. The digested sludge is vacuum filtered and used as land-
fill (see Flow diagram, Figure 5).
Foam development started at the plant around August 1, 1976 when
control measures were initiated as indicated in Table 5 by returning
to the primary tanks 28. 39 m /d (7, 500 gal/d) anaerobic digester
supernatant which was not Purifaxed. This foam development
coincided with a marked increase in amaraemycolate (Table 10).
This was later changed to the use of chlorinated supernatants.
Throughout the study period there was some fluctuation in the amount
of actinomycetic foam produced but foaming reduction, when it
occurred, could not be correlated with the control technique which
did not appear to be effective.
The initial return of unchlorinated anaerobic supernatant created an
odor problem but the use of chlorinated material should still have
been effective since it had equivalent nocardiotoxicity as shown in our
assays (Table 11).
51
-------
Final
Settling
Tanks
Ul
Ni
Chlorine
Contact
Tanks
a
Parshall
Flume
Effluent
Vacuum
Filter
Pump
Digesters
.
Purifax
a --- ±. * -
J 1 Supernatant
-^™
4
I
X^
X^_
\ w
1 ID
>
1
^\ ' Vi Mixer I
^\ ** Tank, '
J i c T<»
/ ' n -u
yC . a i (0
---^ ' ^ >
v I «J ' -H
Primary
Settling
Tanks
1, ^
-f r^-
.
Pumps 1* Stabilizer , %
efb Tanks 1 <
1
' ^
j-^ «--
Flow i
1 c
I3
£
Meters *
L-J-I_ >. _ _
.
HI
D<
2
w
IA
n)
S
>
g
1
•r|
H
O
^-SqJ-^t^p-
£
j-i
«
a
a
-H
O
u
g
3
-------
Table 9. FIELD OBSERVATIONS
OCEAN PLANT
Miscellaneous
Aeration Final Activated Scum/
Date tanks settling sludge foam
tanks condition
May 5, 75 Normal Normal None To keep normal
Ririfax supernatant
treatment
13
Zl
27
June 2
10
19
24
Normal
Normal
Normal
Some
foam in
re-air
Slight
foam
Slight
foam
Minor
foam
Some
slight
scum in
center-
wells
Some
scum
Some
scum
No scum
Minor
scum
Very
minor
scum
Some
scum in
center-
wells
Color good Minor
Color good Minor
Color good Slight
Color good Minor
darkish
Color good Minor
Color good Minor
Good color Minor
ML low
Using H O2 for odor
control
HoO, in use
HO, in use
Z £•
Rain past few days
Sewage temperature
21°C
53
-------
Table 9 (continued). FIELD OBSERVATIONS
OCEAN PLANT
Aeration
Date tanks
July 1, 75 Minor
foam
8 Some
foam
15 No foam
22 Some
foam
29 Some
foam
Final
settling
tanks
Minor
scum,
clarity
fair
Very
minor
scum
Slight
scum,
clarity
good
Slight
scum in
broken
pieces
Some
scum
Activated
sludge
Color good
darkish
Color dark
Color dark
Color good
darkish
Color dark-
ish
Scum/
foam
condition
Minor
Minor
Minor to
none
Slight
Slight
Miscellaneous
ML lower
Sewage temperature
23. 9 ° C. Still using
H2°2
Purifax feed
149.3-186.6 kg
(4-500 tb)/day Cl,
54
-------
Table 9 (continued). FIELD OBSERVATIONS
OCEAN PLANT
Date
Aug. 1, 75
Aeration
tanks
Full of
foam
Final
settling
tanks
Full of
scum
Activated
sludge
Color good
darkish
Scum/
foam
condition
Good
develop-
ment
Miscellaneous
Started control 28. 4 m3d
(7500 gal/day) = 15. 2 cm
(6")/day- Foam built
up 2 days ago.
Sewage temperature
24.4°C.
12 Plenty of Plenty
foam of scum
Color dark Good Odor problem - stopped
develop- control on 8th. Less
ment foam then more now.
19 L«ss foam Less scum Color very
dark
26 Some foam Less scum Color very
dark
Sept. 2 Heavy No center- Color dark
dark foam well scum.
in re-air Surface
scum - 1/2
tanks.
9 Plenty Some Color very
foam scum in dark
centerwell.
Less on
surface.
Reduced? MLSS reduced to keep
Purifax feed low
Reduced Continue low.
Purifax Cl feed.
Medium Purifax feed increased
amount 279.9 kg (750 Ib) day
odors.
Medium Purifax 279.9 kg (750
amount lb)/day. 6 hr + run.
55
-------
Table 9 (continued). FIELD OBSERVATIONS
OCEAN PLANT
Aeration
Date tanks
Sept. 16, 75 Plenty
foam
23 Less
foam
30 Less
foam
Oct. 7 Plenty
foam
14 Plenty
foam
21 Less
foam
28 More
foam
Filial
settling
tanks
More
surface
scum -
low in
center -
well
Less
scum
Some
scum -
breaking
up
Plenty
scum
Plenty
scum.
open
weir
Plenty
scum
Less
scum
Activated
sludge
Color very
dark
Color very-
dark
Color very
dark
Color dark
Color dark
Color dark-
ish
Color good
Scum/
foam
condition
Good
develop-
ment
Reduced
Reduced
Good
develop-
ment
Good
develop-
ment
Good
develop-
ment
Reduced?
Mi s c ellane ous
ML low
Returned supernatant
with no Purifax 17-23;
Rain.
Still not using Cl in
Purifax - Trying to slug
with supernatant.
'
Using no Cl- in Purifax -
will try 2 day w/o Cl
and 5 day with Cl
Using 2 day no Cl In
Purifax supernatam
return
Dropped 56. 8 m3 (15, 000
gallons) supernatant on 20,
Sewage temperature
19.4'C.
Using no Cl in Purifax
on 2 days
56
-------
Table 9 (continued). FIELD OBSERVATIONS
OCEAN PLANT
Date
Aeration
tanks
Final
settling
tanks
Activated
sludge
Scum/
foam
condition
Miscellaneous
Nov. 4, 75 Plenty Some Color good Reduced? Still using no Cl_ 2
foam scum days in Purifax
10 Less Some Color dark* Reduced? End controlling
foam scum ish attempts.
breaking
up
H^O, = Hydrogen Peroxide
ML = Mixed Liquor of Aeration Tanks
Cl_ Chlorine
MLSS = Mixed Liquor Suspended Solids
57
-------
Table 10. ANALYSIS OF RETURN ACTIVATED SLUDGE
OCEAN PLANT
Date
5-5-75
5-13
5-21
5-27
6-2
6-10
6-19
6-24
7-1
7-8
7-15
7-22
7-29
8-1
8-12
8-19
8-26
Suspended Microscopic
solids estimation of
mg/1 nocardial hyphae
4,400
4, 600
4, 000
7, 600
4, 200
5,600
3, 800
2, 600
4, 600
5, 200 +
4, 800 +
5, 400 +
7, 800 +
4, 800 +
5, 800 +
5,600 +
4, 606 +
Mycolate content
|j.g/5 gm dry
sludge solids
0
0
0
19
16
18
9
6
17
111
31
37
87
140
248
150
92
58
-------
Table 10 (continued). ANALYSIS OF RETURN ACTIVATED SLUDGE
OCEAN PLANT
Date
9-2
9-9
9-16
9-23
9-30
10-7
10-14
10-21
10-28
11-4
11-10
11-18
Suspended Microscopic
solids estimation of
mg/1 nocardial hyphae
4,000 +
4, 800 +
3,400 +
4, 400 +
5,200 +
5,000 +
4,000 +
3,800 +
3, 400 +•
4, 400 +
3,800
4,200
Mycolate content
(Jig/5 gm dry
sludge solids
169
117
111
345
188
102
222
156
202
277
59
-------
Table 11. ANALYSIS OF DIGESTER SUPERNATANT
OCEAN PLANT
Date
8-1-75
8-8
8/12-19
8/20-26
8/27-9/2
9/10-16
9/17-23
9/24-30
10/1-10/7
10/8-14
10/15-21
10/22-28
11/4
11/4
Suspended
solids
mg/1
30, 100
20,400
26, 100
30,500
25,500
34, 800
27,800
22, 100
42,500
27,700
23, 100
30,800
29, 300
25,900
mg/ml for
50% inhibition Comments
of N. amarae
1.5
0.9
1.3
1.5
1.7
1.2
1.2
1. 1
0.7
0.4
0.8
1. 1
0. 5 No chlorine
0. 5 279. 9 kg (750 Ib/day)
chlorine Pur if ax
11/5-10
24,000
Av. 1. 1
60
-------
Table 12. PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
OCEAN PLANT
Flow Sew. Temp.
Date
5/1-6
7-13
14-20
21-27
28-6/3
4-10
11-17
18-24
25-30
7/1-8
9-14
m3/d
x 103
14.42
13.17
12.83
11. 39
10.79
10.75
12.98
11.66
10.67
10.60
10.94
M.G.D.
(3.81)
(3.48)
(3.39)
(3.01)
(2.85)
(2. 84)
(3.43)
(3.08)
(2.82)
(2.80)
(2. 89)
Infl.
•c
14.4
14.4
16.7
12. 8
18.9
19.4
19.4
20.6
21. 1
21.7
22.8
pH
Infl.
7. 1
7.0
7.0
7.0
6.9
6.9
6.9
6.9
6.8
-
6.8
Effl.
7.3
7. 1
7. 1
7.0
6.9
7.0
6.9
6.9
6.8
-
6.9
Suspended Solids
Infl.
mg/1
80
90
-
100
80
100
100
110
100
100
-
Effl.
mg/1
8
10
-
10
10
5
10
5
10
5
-
%
REM.
90
89
-
90
88
95
90
95
90
95
-
Infl.
mg/1
83
107
117
73
102
147
88
118
106
128
122
BOD/5
Pri. effl.
mg/l
43
39
42
29
34
93
51
76
39
84
88
Effl.
mg/l
3.5
6.3
9.3
8.3
21
9
8
16
6
18
13
%
REM.
95
94
92
89
79
94
91
86
94
86
89
-------
to
Table 12 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
OCEAN PLANT
Flow Sew. Temp.
Date m3/d
x 103
15-21
22-29
30-8/12
13-19
20-26
27-9/2
3-9
10-16
17-23
24-30
10/1-7
10.90
10.41
10.71
10.41
10.83
10.64
10.86
10.14
10.60
12.98
10.94
M.G.D.
(2.88)
(2. 75)
(2.83)
(2. 75)
(2.86)
(2.81)
(2.87)
(2.68)
(2.80)
(3.43)
(2. 89)
Infl.
°C
23.3
24.4
23.9
23.9
23.9
24.4
23.9
22.2
22.2
21. 1
20.6
pH
Infl.
7.0
6.8
6.7
7.1
7.3
6.7
-
7.4
7.8
7.2
7.0
Effl.
7.0
7.3
7.0
7.3
7.3
7.0
-
7.3
7. 1
7.0
7.2
Suspended Solids
Infl.
mg/l
100
90
137
95
200
-
125
125
110
-
110
Effl.
mg/l
5
5
9.3
5
10
-
10
5
10
-
20
REM.
95
94
93
95
95
-
92
96
91
-
82
Infl.
mg/l
110
132
125
142
108
125
134
. 153
183
85
123
BOD/5
Pri. effl.
mg/l
66
76
73
111
66
67
61
101
101
45
51
Effl.
mg/l
18
20
17
26
20
20
16
14
19
27
22
REM.
84
85
86
82
81
84
88
91
90
68
82
-------
Table 12 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
OCEAN PLANT
Flow Sew. Temp.
Date
8-14
15-21
22-28
m3/d
x 103
11.77
13.17
13.21
29-11/4 12.60
5-10
11-18
19-25
Sew =
Infl =
Effl =
12. 11
12.64
12.57
Sewage
Influent
Effluent
M.G.D.
(3.11)
(3.48)
(3.49)
(3.33)
(3.20)
(3. 34)
(3.32)
Infl.
°C
21. 1
21. 1
20.0
20.6
20.6
18.9
17.2
REM =
BOD/5
pH Suspended Solids
Infl.
7.2
7.6
7.2
7.2
7.1
7.0
7. 1
Removal
Effl. Infl. Effl. %
mg/l mg/l REM.
7.1
7.0 100 10 90
7.1 105 13 88
7.1 - - -
7.0 100 10 90
6.9 110 15 86
6.9 83 10 88
BOD/5
Infl. Pri. effl
mg/l mg/l
117 47
93 59
89 54
83 53
92 54
88 45
78 40
. Effl. %
mg/l REM.
13 89
12 87
16 82
9.3 89
16 83
15 83
15 81
= 5 day Biochemical Oxygen Demand
-------
Table 12 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
OCEAN PLANT
Aeration Tanks
Date
5/1-6
7-13
14-20
21-27
28-6/3
4-10
11-17
18-24
25-30
7/1-8
1070
1260
1180
1140
1260
1720
1870
1420
1380
.1470
MLSS*
mg/1
4390
4570
4200
3800
3440
4600
4700
4090
3940
4220
ML
Set. S
ml/1
180
190
180
390
260
400
290
190
230
320
SVI
168
151
157
209
206
229
190
134
162
217
DO*
mg/1
2.
3.
1.
1.
1.
1.
2.
2.
1.
2.
5/.8
6/1.4
8/.8
8/.9
6/1.0
3/.2
6/.9
6/1.0
1/2.4
0/1.4
Ret. sludge
R
44
44
48
49 .
48
50
43
49
50
49
SS
mg/1
•a
(X)
H
o
• H
nt
0)
a)
tf
03
nl
0)
3
«t
T3
-------
l/l
Table 12 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
OCEAN PLANT
Aeration Tanks
Date
9-14
15-21
22-29
30-9/12
13-19
20-26
27-9/2
3-9
10-16
17-23
1390
1690
1670
1940
1840
1700
1520
1280
1320
1210
MLSS*
mg/1
3980
4990
4280
4430
4420
4180
3800
3460
3700
3040
ML
Set.S
ml/1
340
570
270
320
280
200
200
200
240
190
SVI
244
334
158
163
153
122
130
161
175
166
DO*
mg/1
1.6/.4
2. 0/1.0
1. 2/1.2
1.8/1.1
1.9/2.6
3.4/2.2
2. 7/2.6
1.6/1.6
1.6/2.3
1. 1/1.7
Ret. sludge
% ss
R mg/1
50
50
52
51
50
43
51
50
46
57
Digester
Sup'n
Gal % TS
45,000
1
i — i *"O
S 13 -S
h (X g
o M S
£+ O (!)
T!§ «
.£ - Q
tH 00 ^
O i-< o
1 *
-------
O
Table 12 (continued). PLANT OPERATING RECORDS
(WEEKLY AVERAGES)
OCEAN PLANT
Aeration Tanks
Date
24-30
10/1-7
8-14
15-21
22-28
29-11/4
5-10
11-18
19-25
1010
1200
1540
1090
860
1100
1540
1160
1240
MLSS*
mg/1
3410
3640
3800
3080
2720
3310
3680
2810
3000
ML
Set. S
ml/1
170
190
240
150
120
110
130
110
110
SVI
170
160
155
139
138
110
85
95
89
*
DO
mg/1
1.8/.6
2.0/1. 1
1.0/.8
1.6/1.2
2.0/1.4
1.6/1.0
1.2/.8
1.0/.6
1.0/.8
Ret. sludge
% SS
R mg/1
45
54
48
43
45
45
46
47
45
Digester
Sup'n
Gal % TS
1
o
o
o
00
i
"it
C
0
2
•a
4)
h
O
1
•a
11
c
1
4)
Q
+J
0
2
Mixer and reaeration tanks.
See legend at the end of Table 4.
-------
O
o>
4)
O
w
O
O
c
o
s.o
M 4.0
TJ
"5
10
a
M
*O
0
3X>
2.0
1.0
Ocean Township, August to November 1975
Supernatant Toxicity and My cola te liters
in
XI
(0
o
XI
~M
i_
TJ
E
D>
tn
01
400 o
o
u
3OO
200
»
o
E
cn
u
00 <
"3/Tf
a/23
6/6
9/16
9/23*9^9
1375 | - 16/14-10/21 | - IPT
10/7-10/13 KV22-IO/27
11/4
Figure 6. Nocardotoxicity of the Supernatant from the Anaerobic Digester
and Nocardiomycolate Contents of Sludge Solids at the Ocean
Township Plant from August 1 to November 4, 1976
-------
The ineffectiveness of the control technique at the Ocean plant
might be attributed to the method of supernatant return which is
controlled by plant personnel through the operation of a 3. 2 1/s
(50 gal/min) pump for an average of 6 hours during the latter
part of the day. It is quite likely that at this low rate of return
a substantial amount of the anaerobic solids were removed in the
primary sedimentation tanks with the raw sewage solids. In
addition, plant records are not kept on this operation and dis-
ruptions of the duties of plant personnel might have resulted in
alteration of the schedule of supernatant return.
More important, however in explaining the lack of control observed,
is the design of the plant which is such that foam and scum from the
secondary clarifiers are returned to the secondary aeration tanks.
Since the foam is composed almost exclusively of air and filaments
of nocardia, the design of the plants is such that the secondary
system is constantly reinoculated with a heavy dose of the nocardias.
68
-------
SECTION X
COMPARISON OF THE RESULTS OBTAINED AT THE
FLORHAM PARK, MIDDLETOWN AND
OCEAN TOWNSHIP PLANTS
An examination of the records of the plants (Tables 4, 8 and 12)
shows that the addition of anaerobic supernatant in the doses used
did not reduce the quality of the effluent in any of the three plants
studied. The only problem of this type observed was the upset of
November 4, 1975 at the Florham Park plant caused by the
accidental dropping of 3 to 4 times too much supernatant into the
system.
A review of these operating records further indicates that each of
the plants was operating in a generally normal manner throughout
the study period and that there was a general similarity between the
plantso
The data show that the three plants were very similar in sewage
temperature, pH, influent suspended solids, and BOD levels,,
Likewise, the mixed liquor suspended solids in the aeration systems
of the facilities appeared generally similar. The mixed liquor suspended
solids and sludge volume indices varied within reasonable limits.
One major difference between the treatment facilities was the age of
the sludge under aeration. As shown in Table 13, the sludge age at
Middletown and Ocean was very similar, averaging 4. 5 and 40 2
days respectively but was almost double (7.8) at the Florham Park
plant. This long period of aeration may have-caused trouble in
controlling the actinomycfetes by increasing the degradation of the
nocardiotoxic material.
69
-------
Table 13. SLUDGE AGE IN DAYS
Date
5/1-6
7-13
14-20
21-27
28-6/3
4-10
11-17
18-24
25-30
7/1-8
9-14
15-21
22-29
30-8/12
13-19
20-26
27-9/2
3-9
10-16
Middletown
4.4
3.8
3. 1
5.5
3.9
4.4
5.2
4.2
4. 1
4.6
5.9
4.2
4.1
4.9
4.5
4.0
4.3
3.9
5.6
Ocean
4.7
4.9
4.6
4.3
5.3
5.7
4.9
4.2
4.9
5.2
4.8
6.0
6.2
4.2
6.1
2.6
2.8
3.4
3.9
Florham Park
7.2
8.8
10. 8
8.2
5.6
6.1
7.9
11. 5
9.8
11. 1
7.8
10. 1
12.4
12.6
19.9
8.7
13.5
11.9
12.1
70
-------
Table 13 (continued). SLUDGE AGE IN DAYS
Date
17-23
24-30
10/1-7
8-14
15-21
22-28
29-11/4
5-10
11-18
19-25
26-12/2
Average
Middletown
4. 5
3.8
5. 1
3.9
3.5
4.9
5.0
3.8
5.6
4.5
4. 5
Ocean
3. 5
3. 1
3.9
4.0
3. 1
2.5
3.4
4.2
2.8
4.0
4.2
Florham Park
12.4
5. 1
15. 3
10. 1
7.0
12.6
9.4
9.5
13. 5
10. 1
9.4
7.8
*
Based on assumed 20% removal in primaries.
71
-------
Another difference between the three treatment plants was in the
method of return of the scum and foam from the secondary clarifiers.
These were periodically removed for landfill disposal at Florham
Park, were sent to the anaerobic digesters at Middletown but were
returned to the secondary aeration tanks at Ocean. This last practice
is detrimental since it results in the constant reintroduction of the
nocardia into the secondary system which is where trouble develops in
the plant.
Conclusions.
In general, the nocardiotoxicities of the anaerobic supernatants of all
three plants (Tables 3, 7 and 11) were equivalent, averaging (for 50%
inhibition of N. amarae Se 6) 1. 1 mg/ml at Ocean, 1. 3 mg/ml at
Florham Park and 2. 3 mg/ml at Middletown. These averages were
based on the 10 week period of August 1 to October 13 for which
equivalent data for each plant are available.
In Middletown, the decreases in nocardiotoxicity of the anaerobic
supernatant coincided with its removal by barging. In this plant,
the decrease in nocardiotoxicity also preceded or coincided with an
increase in amaraemycolate levels and foam formation. Further-
more, the two major foamouts (September and November) in this plant
were probably enhanced at critical moments by the fact that there were
periods when no supernatant was returned to the system because of
operational problems.
The nocardiotoxic principle is also inhibitory to two fecal gram-
negative bacteria tested, but not to a gram-positive one.
No evidence for increased resistance of N. amarae to the nocardio-
toxic principle was found.
72
-------
SECTION XI
THE BAYSHORE PLANT
Toward the end of July 1975 the Bayshore Regional Sewerage
Authority Treatment Facility at Union Beach, N. J. was
experiencing a severe foaming problem. The foam was tested and
found to contain nocardias (N. amarae and N. rhodochrous). This
plant is a 22, 710 mr/d (6 mgd) activated sludge plant and utilizes
gravity thickeners and an incinerator for solids disposal. On
checking the plant, a source of anaerobic material was found in
the sludge from the bottom of the gravity thickeners. This
material was septic and on testing was found to have a good
liocardiotoxicity.
Utilizing this material, plant personnel set up a temporary means
of feeding the thickened material directly into one of the aeration
tanks. This toxic material was fed into the aeration system on a
weekly basis at a rate of approximately 15. 1 rrr (4000 gal) per
mgd per week. This control method was started on August 7 and by
the first of September the foam had been greatly reduced (see Table
14). This low level of foam and the weekly dosing continued through
to the middle of the month. At this time the incinerator had to be
taken out of service and resulted in excessive solids accumulations
in the thickeners leading to a constant overflow of septic material
back through the plant system. During the time of this constant
septic feed, the small amount of foam was further reduced until
there was no foam on the final settling tanks by the end of September.
The incinerator was started again in the beginning of October and
operated periodically through to the end of October. During this
period of time a slight foam buildup appeared in the final settling
tanks; however, the operating personnel felt it was not significant
enough to reinstitute the controlling measures at this time. The
complete elimination of surface scum on the final settling tanks at
the end of September may be a result of more than the controlling
feed of septic material at the plant. The plant personnel report that
on one day the mixed liquor solids were lost in the system and
suspect that they may have received a slug of industrial waste that
upset the system. It is possible that such an industrial waste may
73
-------
have aided in the elimination of the minor amount of remaining
foam at the plant at that time. In Table 15 will be found a
summary of the operating records of the Bayshore plant during
the study period.
It is felt, however, that the use of the septic feed as a controlling
technique at the plant did reduce the large initial foam
accumulation to a low level and that it did not present any nuisance
in the plant operations.
74
-------
Table 14. FIELD OBSERVATIONS
BAYSHORE REGIONAL PLANT
Date
Aeration
tanks
Final
settling
tanks
Activated
sludge
Scum/
foam
condition
Miscellaneous
July 29,1975 Full of Heavy 5 cm
light brown thick scum
foam darkish
Aug. 1
12
19
26
Sept. 2
16
Full of
foam
Heavy 5 cm
scum
Less foam Less scum
Plenty
foam
Plenty
scum
Same or Same or
somewhat somewhat
less less
Very little Very little
foam 3 cum
Some foam Some light
scum 1/2
tank
Some foam Some light
scum
Color darkish Very
severe
Color darkish Very
severe
Color darkish Reduced
Color darkish Increased
Color darkish Reduced?
Color dark
Color dark
Color dark
Reduced
Problem started 7/14±.
Sampled scum and
thickener sludge.
Operator to feed 2, 000
gal ± of toxic thickener
sludge to aeration tanks
as slug -
Fed slug of thickener
sludge 2 days 6 and 7th ±
foam dropped to low level
on llth.
Fed thick sludge on 13th
and 18th. No apparent
reduction.
Will return sludge to
day.
Fed sludge on 26th and
will today also. Heavy
scum on 27 and 28.
Minor to Some scum buildup on
slight 4th - dropped thickener
sludge on 8th.
Slightly No sludge feed since
increased 8th - was less scum
but minor yesterday.
75
-------
Table 14 (continued). FIELD OBSERVATIONS
BAYSHORE REGIONAL PLANT
Date
Aeration
tanks
Final
settling
tanks
Activated
sludge
Scum/
foam
condition
Miscellaneous
Sept. 23, 1975 Light foam No scum Color dark
30 Black Very minor Dark color
foam to none
Reduced No sludge since 8th - have
thickener heavy solids
overflow - incinerator out
15th to 18th ±. Lost
solids in air tanks.
Reduced No sludge feed - heavy
to low solids in thickener over-
level flow.
Oct. 7
14
21
28
Nov. 11
18
No foam
Light
foam
greyish
Light
grey
froth
Light
foam
Grey
froth
Grey
froth
Slight
scum
particles
#2 and #3
No scum
Color dark Low level
Color dark Low level Industrial waste problem?
No sludge feed.
No scum Color dark
Slight scum Color dark
on #3
None to No sludge feed. Toxic
low level industrial slug?
Low level No sludge feed.
None Color dark Low level Received toxic
to none industrial slug?
None Color dark Low level
76
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Table 15. OPERATING RECORDS
BAYSHORE REGIONAL PLANT
Date
July 29, 1975
Aug. 6-7
13
18
26
Sept. 2
4
8
16
Flow
m3/d M. G.D.
x 103
16.65 (4.4)
17.0 (4.5)
16.65 (4.4)
16. 27 (4. 3)
16.65 (4.4)
Aeration
MLSS
mg/1
2,200
2,400
2.600
2,900
3,220
2,800
3,380
3,500 ±
Thickener
sludge
feed
m3
37.8
56.8
39.7
7.6
7.6
Thickener
sludge
feed
gallons
Unknown
10,000
15,000
10,500
2,000
2,000
Thickener
sludge
susp. solids
%
Unknown
3.9
3.8
4.1
2.9
3.6
77
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SECTION XII
DISCUSSION
We have attempted to control actinomycetic foam in the secondary
system of four sewage treatment plants of the activated sludge
type by addition of anaerobically digested material. Control has
been observed in two plants and failure in the two others. We
should try to analyze the reasons for these successes and failures.
Good control was obtained at the Bayshore plant by adding septic
thickener material with demonstrated nocardiotoxicity directly to
the intake of the secondary aeration tanks. We feel that this is an
important point. This was the only plant where it was possible to
go directly to the secondary aeration tanks and we feel that, in
other plants, during the passage through primary treatment, a part
of the nocardiotoxic solid material was removed, making control in
the secondary tanks difficult.
We feel that the poor results observed at the Ocean Township plant
is due to the fact that we could not add the nocardiotoxic material
directly to the secondary aeration tanks and that in addition, the
nocardia-containing foam and scum from the secondary clarifier
were returned into the secondary aeration tanks.
The poor results observed at the Florham Park plant were probably
due to the removal of part of the nocardiotoxic material during
primary treatment coupled with the long retention time of the sludge.
In the case of the Middletown plant, good results were observed but
we feel that they would have been more spectacular if we could have
added the nocardiotoxic material directly to the secondary aeration
tanks. In the case of this plant, there was no other adverse factor
to deal with. The foam and the scum, rich in nocardia were not
returned into the system and the retention time was not long.
78
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In general the nocardiotoxicity of the anaerobic digester
supernatant solids of the three plants studied was equivalent.
Through the study period, the 50% inhibition point of N. amarae
Se 6 averaged 1. 1 mg/ml at Ocean, 1. 3 mg/ml at Florham Park
and 2. 3 mg/ml at Middletown.
At the Middletown plant, the decreases in nocardiotoxicity of the
anaerobic digester supernatant coincided with the barging of the
anaerobic sludge. In this plant, the decrease in nocardiotoxicity
also preceded or coincided with an increase in the levels of the
typical mycolate of Nocardia amarae and with foam formation.
Furthermore, the two major foaming incidents which occurred in
September and November at the Middletown plant were probably
enhanced at critical moments by the fact that there were periods
when no supernatant was returned into the system due to operational
problems.
The amaraemycolate (AM) levels averaged from approximately 25
samples from each of three plants showed a direct relationship with
the extent of foam observed. In the Middletown plant, AM levels
averaged 56.5 mcg/5 gm of dry weight sludge solids. This plant had
the least problem with foam. The Ocean Township plant had an
average of 106 meg AM/5' gm, with the principal increased AM levels
encountered toward the end of the observation period when the major
foam-out began. Florham Park, which showed an intractable foam
throughout the period of study showed an average of 367 meg AM/5
gm.
If we try to put together all the information we have on nocardial
foaming we would suggest that control might best be achieved by
wasting activated sludge to bring the mixed liquor suspended solids
to 2, 000-2,500 mg/1 while adding anaerobic digester supernatant
directly to the activated sludge. Our best estimate is that for an
anaerobic digester producing supernatant with the type of nocardio-
toxicity we observed, one should add 50-100 kg per day of
anaerobic digester supernatant solids per 1000 kg mixed liquor
suspended solids.
79
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SECTION XIII
REFERENCES
1. Lechevalier, H. A. , "Actinomycetes of sewage-treatment
plants, " Environment Protection Technology Series Report
EPA-600/2-75-031, September 1975.
2. Lechevalier, M. P. , and Lechevalier, H. A. , "Nocardia
arnaraesp. nov. , an actinomycete common in foaming activated
sludge. Intern. J. System. Bacteriol. 24(2): 278-288, 1974.
3. Lechevalier, M. P., Horan, A. C., and Lechevalier, H.,
"Lipid composition in the classification of Nocardiae and
Mycobacteria. J. Bacteriol. 105(1); 313-318, 1971.
4. Lechevalier, M. P., Lechevalier, H., and Horan, A. C.,
"Chemical characteristics and classification of nocardiae."
Can. J. Microbiol. _19(8): 965-972, 1973.
5. Waksman, S. A., "The Actinomycetes, " Chronica Botanica,
Waltham, Mass., 1950.
80
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/2-77-145
2.
3. RECIPIENT'S ACCESSION-NO.
4. TITLE AND SUBTITLE
ACTINOMYCETES OF SEWAGE-TREATMENT PLANTS
5. REPORT DATE
August 1977 (Issuing Date)
6. PERFORMING ORGANIZATION CODE
7.AUTHORIS) Hubert A. Lechevalier, Mary P. Lechevalier,
and Paul E. Wyszkowski
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Waksman Institute of Microbiology
Rutgers, the State University of New Jersey
P.O. Box 759
Piscataway, New Jersey 08854
10. PR
Wfffi
LEMENT NO.
11. CONTRACT/GRANT NO.
R803701
12. SPONSORING AGENCY NAME AND ADDRESS
Municipal Environmental Research Laboratory—Cin.,OH
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
13. TYPE OF REPORT AND PERIOD COVERED
Final. 1975-76
14. SPONSORING AGENCY CODE
EPA/600/14
15. SUPPLEMENTARY NOTES
Project Officer: Ronald F- Lewis (513) 684-7644
16. ABSTRACT
In some activated sludge sewape treatment plants a thick foam rich in
Nocardia may be formed at the surface of the seconHary aeration and settling tanks. It
had previously been observed that the supernatant from anaerobic digesters contained
suspended solids which were toxic for Nocardia. In the present study attempts were
made to control the foam by returning the supernatant from digesters in four plants
to the primary system. The nocardiotoxicity of the supernatant solids was tested
to be sure that toxic material was returned to the system. Laboratory studies showed
that the material is toxic for some bacteria and not for others.
The results indicated that this method of control is difficult to use at full-seal
plant level and indicates that better results might be obtained if the toxic super-
natant was added directly to the activated sludge aeration basins rather than added
to the incoming sewage or the primary settling basins.
•
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COS AT I Field/Group
*Activated sludge process
*Nocardia
Waste treatment
Microorganism control (sewage)
Foam
Problem
13B
18. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY C.LASS (This Report)
Unclassified
21. NO. OF PAGES
91
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
81
•ft U.S. GOVERNMENT PRINTING OFFICE: 1977—7574)56/6492
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