312 GEOSYNTHFT C TESTING FOR WASTE CONTAINMENT APPLICATIONS
[15]	Chen, Y. H,, Simons, D. B,, and Demery, P. H,, "Hydraulic Testing
of Plastic Filter Fabrics", Journal of the Irrigation and
Drainage Division. ASCE. Vol. 107, No. IR3, 1981, pp. 307-325.
[16]	Lu, J. C,, Eichenberger, B., and Stearns, R. J., Leachate from
Municipal Landfills: Production and Management. Noyes
Publications, Park Ridge, 1985.
[17]	Cancel!i, A., and Cazzuffi, D., "Permittivity of Geotextiles in
Presence of Water and Pollutant Fluids", Proceedings of the
Geosynthetic '87 Conference. Vol, 2, Industrial Fabrics
Association International, St. Paul, 1982, pp. 471-481.
[18]	Koerner, G. R., and Koerner, R. M,, "Biological Clogging in
Leachate Collection Systems:, in Proceedings of a Seminar on
Durability and Aging of Geosvnthetics. Geosynthetic Research
Institute, Philadelphia, 1988.
[19]	Rosson, R. A., Tebo, B, M., and Nealson, K. H., "Use of Poisons
in Determination of Microbial Manganese Binding Rates in
Seawater", Applied and Environmental Microbiology. Vol. 47, No.
4, 1984, pp. 740-745.
[20]	Polyfelt Inc., product specification sheet, Evergreen,
Alabama.
[21]	Gerhardt, P., Murray, R., Costilow, R., Hester, E., Wood, W,,
Krieg, N., and Phillips, G., Eds., Manual of Methods for
General Bacteriology. American Society for Microbiology,
Washington, DC, 1981.
EPA/600/A-92/053
George R, Koerner and Robert M, Koerner
BIOLOGICAL ACTIVITY AND POTENTIAL REMEDIATION INVOLVING
GEOTEXTILE LANDFILL LEACHATE FILTERS
REFERENCE: Koerner, C. R. and Koerner, R. H., "Biological
Activity and Potential Remediation Involving Ceotextile
Landfill Leachate Filters," "Geosynthetic Testing Cor Waste
Containment Applications, ASTM STF 1081, R. M. Koerner, Ed %,
American Society for Testing and Materials, Philadelphia, 1993
ABSTRACT; This paper presents the results of a biological
growth study in geotextile filters used in landfill leachate
collection systems. After reviewing the first year's activity,
a completely new experimental approach has been taken. Using
100 mn diameter columns for the experimental incubation and
flow systems, the effects of six landfill leachates are
evaluated. Aerobic and anaerobic states, four different
geotextiles, and soil/no soil conditions above the geotextiles
are involved in the testing program. This results in 96
individual test columns. Flow data is measured regularly, and
over the first six months of evaluation the following trends
have been observed.
*	no clogging (0%~25% flow reduction)
6 of 96 columns 71
*	minor clogging (25%~50% flow reduction)
4 of 96 columns = 4%
*	moderate clogging (501-75% flow reduction)
37 of 96 columns » 38%
» major clogging (75%-95% flow reduction)
35 of 96 columns =* 36%
*	severe clogging (95%-100% flow reduction)
15 of 96 columns - 15%
For two of the landfill leachates, backflushing has been
attempted so as to reinstitute flow. This procedure works well
for the geotextile alone while not as well for the geotextile/
soil columns. The exception is the nonwoven heat set geo-
textile . All tests are still ongoing and will be dismantled and
further investigated at the end of 12 months exposure time. The
experimental setup and procedure has been written up as a ten-
tative ASTM test method and is currently in task group review.
G. R. Koerr\er is Senior Research Specialist and R. M. Koerner is
Director and Professor at the Geosynthetic Research Institute, Drexel
University* Philadelphia, PA 19104
313

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314 SEMISYNTHETIC testing for waste containment applications
KEYWORDS: biological clogging, aerobic, anaerobic, soil clogging,
gectextile clogging, fUtration, leachate, bacteria count, viable
count	*	c
INTRODUCTION
The leachate collection systems used above and below primary
mers in landfills are meant to function in a free flowing
gravitational mode for their entire active and post closure care
periods. Such leachate collection systems consist of a drainage
te^ther sand-	or a geonot), a protective filter
(either sand or a geotextile), and sometimes a perforated pipe covered
"i h an appropriate filter (either sand, gravel or a geotextile)
Figure 1 show, the location of these trials where geoaynthetl;
alternates are illustrated. It should be noted that a fine grained
SOI (Silt, clay or mixture) is frequently placed between the leachate
collection 3ystem and the waste. This layer if often referred to as
an operations layer" or "working surface". Due to its small void
leachate6 Ur"	micr°-"or3anis™ and fine sediment in the
leachate. This condition ia not modeled in the tests to be described
this paper, while both natural materials and their geosynthetic
tes^methnrtt Cth ^ deaTed "3ing 3tate-of-the-art techniques and
test methods, the general focus is usually on short-term performance
also be Addressed oh -° T" required' ^ng-term concerns must
important ?i 71 i' ?	durabiii^ and aging concerns are vexy
important [1,2 , but concern that the leachate collection system
buildCo ffSh f t"3 t3 alSO in,p°ttant- WiUl cl°3ging will come a
within the wafte ™ T °" ^	crPatin:' a	of saturation
withm^ the waste. Thus long-term clogging becomes an issue since it
ParM^rV T Slther Particulate or biological mechanisms,
lation^' t clo«9"9 ha* been evaluated in a number of test simu-
lations, e.g. gradient ratio [3], long-term flow [4] and hydraulic
conductivity ratio [5] tests. Biological clogging, however, has only
recently been addressed [6) and/or evaluated [7,81 This oacer i,
focused toward a continuation of an earlier report on biological
th«t9initifl9enteXtllea«nd represents Edifications and extensions o£
cnac initial one year effort.
OVERVIEW OF FIRST PH&SE OF PROJECT
It is well recognized that municipal landfill leachates contain
large amounts of various microorganisms, primarily different forms of
northeast reoi'on VlT'i.c!!0 biolo9ical counts at six landfills in the
northeast region of the USA. The total direct count measures all
bacteriar while the viable titer gives the living bacteria count in
nits of number of cells per milliliter of leachate. Note the
landfuflea	"Umbe"' Che»ical analysis data on these same six
t .! V T" ate 9fVe" ln Table *' " " evident	this data
hat each leachate is unique. The BODs values are generally considered
to be the best indicators of the available biological activity.
This information certainly suggests that biological activity is
present and when combined with ^derate-to-warm temperatures (as
occurs at the bottom of a landfill) and an ample food source (as
contained in domestic waste), the growth of bacteria within the
KOERNER AND KOERNER ON BIOLOGICAL ACTIVITY
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316 GEOSYNTHETIC TESTING FOR WASTE CONTAINMENT APPLICATIONS
leachate collection systems is certainly possible. Further
consideration of the situation would suggest that the filter (rather
than the drain) should be the focus of attention since it contains the
smallest voids through which the leachate must flow. This is the case
for both fine to medium sand filters and geotextile filters since
their void diameters are approximately the same, however, their
thicknesses are significantly different. The point to be made is that
both sand and geotextile filters should be evaluated for their
biological clogging potential.
The first phase of this project 19] evaluated seven different
geotextiles (a minimum of four per site) in aerobic flow boxes with
sand above them, and an additional four in anaerobic incubation drums
with subsequent flow and strength tests. The study was performed at
six landfill sites and lasted for twelve months. From the aerobic flow
tests it was found [9];
(a)	that flow rate reductions were from 40% to 100%,
(b)	that geotextile opening size played a key role, with larger sizes
allowing for passage of the clogging sediment and/or dormant
bacteria,
(c)	that the type of geotextile polymer is of no great significance,
(d)	that soil clogging could not be separated from geotextile
clogging, and
(e)	that particulate clogging could not be distinguished from
biological clogging.
From the anaerobically incubated samples it was found [9];
(a)	that flow rate reductions were from 10% to 40%,
(b)	that the biological buildup was cumulative as confirmed by
photomicrographs which showed progressively greater biological
attachment over the 12 month testing period, see Figure 3,
(c)	that there was no physical attachment of the biological growth to
the geotextile fibers, and
(d)	that there was no strength loss of the geotextile over the
12-month incubation period
Building upon these results, a second phase of the project was
aimed at eliminating the objectionable features of the first phase and
providing for an opportunity to remediate the filtration systems by
backflushing. The results of this second phase activity follows for
the remainder of the paper.
DETAILS OF CURRENT PROJECT
It is felt that, the new test columns for this second phase of the
study of biological activity in landfill filters must meet the
following criteria.
(a)	Sand filter clogging should be distinguishable from geotextile
filter clogging.
(b)	Particulate clogging should be distinguishable from biological
clogging.
(c)	Partly saturated (aerobic) clogging should be distinguishable from
saturated (anaerobic) clogging.
KOERNER AND KOERNER ON BIOLOGICAL ACTIVITY 317
(d)	Identical geotextiles should be used at every site.
(e)	The flow columns should be capable of accommodating continuous or
periodic flow testing.
(f)	The flow columns should use the leachate at the time of testing
and not be stored for any length of time least it change in its
compos it ion.
(g)	Constant head or variable head conditions should be capable of
being accommodated.
(h)	The flow columns should be capable of being backflushed with
leachate and the results assessed.
(i)	The flow columns should be capable of being flushed from either
side with biocide and the results assessed.
In order to meet these needs, flow columns as shown in Figure 4 have
been developed and are used in this second phase study. It must be
cautioned, however, that some owners or agencies may not allow
backflushing as a remediation method.
The flow columns of Figure 4 are constructed out of commonly
available 100 mm diameter PVC pipe and related fittings. The
containment ring is actually a pipe coupling which has a raised inner
"lip" upon which the geotextile is placed and sealed. A non-water
soluble adhesive is used to bond the geotextile to the lip and to
prevent edge leakage. The upper and lower tubes are both 100 mm long
pieces of pipe and they are contained by end caps which have 25 mm
holes pre-drilled in them and are threaded. Support gravel is placed
below the geotextile prior to positioning and gluing the lower end
cap. Similarly, if soil is to be placed above the geotextile it must
be done before the upper end cap fixed. End cap adaptors are then
threaded into the end caps and fitted with 25 mm flexible tubing (for
constant head tests) or rigid tubing (for variable head tests) . These
two options are shown in Figures 5 and 6, respectively, along with
photographs of the completed devices. The experimental design for this
second phase study was as follows:
•	Four identical (continuous filament) geotextiles were used at each
site and under each set of conditions:
•	240 g/m2 woven monofilament of 0.21 mm average opening size and
6% open area
•	140 g/m? nonwgven heat set of 0.21 to 0.15 mm average opening
size
•	270 g/m2 nonwoven needle punched of 0.21 mm average opening size
•	540 g/m2 nonwoven needle punched of 0.15 mm average opening size
•	Soil (uniformly graded Ottawa sand of 0.42 mm average size) was
placed above one set of the geotextiles, while nothing was placed
above another set.
•	One set of all of the above mentioned columns was allowed to drain
between readings (thus providing aerobic conditions), while another
set was constantly immersed in leachate (thus providing essentially
anaerobic conditions). Note that throughout this paper we will
refer to this setup as being anaerobic due to its full saturation
conditions. It is very possible, and perhaps even likely, that some
small amount of air enters the system greatly complicating the
actual bacterial composition.
•	All of the above variations were done at each of the six landfill

-------
318 GEOSYNTHETIC TESTING FOR WASTE CONTAINMENT APPLICATIONS
sites, thus 96 (4X2x2x6) flow columns Of the type shown in
Figure 1 are included in this study.
RESULTS OF CURRENT PROJECT
This section describes the results of individual studies using the
flow columns just described. The subsections to be described are, (a)
continuous short term flow tests, (b) periodic long term flow results,
and (c) the effects of leachate backflushing.
Since all o£ the tests during the first year were performed on a
monthly basis, and the distinction between fine particulate clogging
versus biological clogging was never settled, a set of continuous flow
tests were performed. Here the flow columns were set up in a variable
head mode, as shown in Figure 6, and leachate was continuously
supplied directly from a leachate sump and passed through the system.
The geotextile/soil configuration was used so that flow times were
long enough to be accurately measured. The results of this testing at
the two sites with the harshest leaehates, DE-3 and NJ-4, are shown in
Figure 7. After an initial decrease which was probably a tuning of the
aoil/geotextile system to the flow regime and the formation of a
stable flow network, the permeability of each leachate leveled off to
essentially constant values. Thus it was felt that what sediment is in
the leachate does not continue to build up so aa to stop, or even
substantially decrease, the system's flow. This suggests that the
short term filtration characteristics of the soil and the geotextile
are adequate to handle the indicated flow rates. It furthermore,
provides a reference plane to which the long-terra flow rates can be
compared. Such long-term flow tests are the focus of the next
section.
Long term flow evaluation of the columns at all six landfill sites
were undertaken. Variable head tests of the sixteen variations at each
site were performed for six months. Figures 8, 9, 10 and 11 give these
results for each of the four geotextiles mentioned in the previous
section. They are the.woven, nonwoven heat-set, light nonwoven needled
and heavy nonwoven needled geotextiles respectively. The anaerobic
results are on the left sides of each figure and the aerobic results
are on the right sides. The soil covered geotextiles are the upper
curves, while the geotextiles by themselves are the lower curves for
each figure. The coding on the graphs for the various test conditions
is as follows.
WM(NS-E?	- woven monofilament (non-calendared) polypropylene
NW(H5)-PP	= nonwoven (heat set) polypropylene
NW(NS-PET 8 oz = nonwoven (needled) polyester of 8 oz/yd^ weight
NW (N) -ptT 16 oz - nonwoven (needled) polyester of 16 o-z/yd? weight
AN/S	» anaerobic condition with sand above
A/5	" aerobic condition with sand above
ftN/W	- anaerobic condition without sand above
A/S	<= aerobic condition with sand above
KOERNER AND KOERNEB ON BIOLOGICAL ACTIVITY 319
Some observations on the trends observed in Figures 0 to 11 are worthy
Of note.
•	The anaerobic flow behavior is remarkably similar to the aerobic
flow trends insofar as the system permeability ia concerned.
•	The tests with sand above the geotextiles are much smoother in their
trend3 than those of the geotextiles alone which have very abrupt
changes-in permeability.
•	In general, the sand/geotextile systems gradually decreased in their
permeability with the nonwoven heat set geotextile of Figure 9
showing the greatest decrease after six months.
•	Viewing the entire set of data collectivelyf we find the following:
no clogging <0%~25% flow reduction!
6 of 96 columns * 7%
•	minor clogging <25%—50% flow reduction)
4 of 96 columns *s! 4%
moderate clogging (50%-75i flow reduction)
37 of 96 columns *= 38%
» major clogging (75%-95% flow reduction)
35 of 96 columns 3» 36%
•	severe clogging ^95%-1004 flow reduction)
14 of 9G columns » 151
•	Within this group, the leaehates of DE-3 and NJ-4 resulted in the
greatest amount of clogging. They will be focused upon in the next
section.
Paralleling efforts in the sewer pipe cleaning, agricultural drain
cleaning and sewage treatment filter cleaning businesses, it appears
worthwhile that we should attempt backflushing. Each column was
backflushed using the site specific leachate at the end of its six
month incubation, i.e., at the terminus of the graphs shown in Figures
8 to 11. Backflushing was done from the bottom of the geotextile at a
constant head of 60 cm for a period of 15 minutes. The head was
sufficiently low so aa not to have liquifaction of the sand above the
geotextile for those cases where the system had sand. The percent
recovery determined by performing regular flow tests after the
backflushing is given in Table 2. Note that in all cases the
geotextile by itself was restored to a higher recovery flow rate than
the sand/geotextile combinations with the exception of the nonwoven
heat set geotextile. when the columns are dismantled we will examine
this situation carefully.
Within the following month after this flow rate recovery, flow
again was seen to decrease. These trends, however, are still being
developed. We anticipate patterns such as illustrated in Figure 12,
A number of -features of these curves are of significance. They show
the periodicity of required backflushing, how biocide introduced into
the backflush affects the situation, and the net recovery reinstated
after each backflushing. Work Is ongoing in this regard.

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320 GEOSYNTHET1C TESTING FOR WASTE CONTAINMENT APPLICATIONS
TABLE 2 — Percent flow rate recovery after leachate backflushing at
60 cm head for 15 minutes.
Biological
Material
Geotextile Type

Landfill
Site
Condition
Above


DE-3
NJ-4

Geotextile




anaerobic
sand
woven monofilament
60%
50%
aerobic
sand
woven monofilament
40
40
anaerobic
no sand
woven monofilament
100
100
aerobic
no sand
woven monofilament
100
100
anaerobic
sand
nonwoven heat set
60
45
aerobic
sand
nonwoven heat set
40
40
anaerobic
no sand
nonwoven heat set
5
10
aerobic
no sand
nonwoven heat set
5
S
anaerobic
sand
light nonwoven
needled
60
60
aerobic
sand
light nonwoven
needled
60
40
anaerobic
no sand
light nonwoven
needled
BO
75
aerobic
no sand
light nonwoven
needled
60
£0
anaerobic
sand
heavy nonwoven
needled
60
55
aerobic
sand
heavy nonwoven
needled
60
40
anaerobic
no sand
heavy nonwoven
needled
100
85
aerobic
no sand
heavy nonwoven
needled
50
65
SUMMARY AMP CONCLUSIONS
The long term drainage of leachate collection systems at landfill
sites ia of major importance in understanding leachate management
strategies, If the filters for such drains clog (via-either
particulate or biological activity!, the hydraulic head on the filter
will increase, forcing saturated leachate conditions into the waste
mass itself. The indications from the first year's study of this
project, and the repetition with a greatly improved containment device
over a subsequent six months, strongly suggests that such clogging and
leachate buildup will occur. From the second generation flow devices
presented in this paper it appears aa though the majority of clogging
is biologically oriented rather than particulate. The times for
severe clogging (arbitrarily defined as a flow reduction of 95% or
more) for the different soil/geotextile and geotextile systems are
relatively short. It was seen that the geotextilea by themselves
exhibited a dramatic decrease in flow soon after biological activity
initiated. In contrast, the geotextile/soil systems exhibited gradual
decreases in flow after biological activity initiated. We feel that
the soil affords a thickness (or buffering! effect which is not
available to the geotextile by itself.
In order to alleviate the clogging, leachate backflushing tests
were performed on all 96 incubation devices. The improvement was
remarkable: approximately 51% flow rate increase for the
sand/qeotextile combinations and 63% for the geotextilea by
KOERNER AND KOERNER ON BIOLOGICAL ACTIVITY 32'
themselves. Of course, some {or all) of the clogging may return. That
is precisely the stage we are currently investigating.
In closing it should be emphasized that many different leachate
collection cross sections are possible and we have examined only two
of them, i.e., the geotextile by itself and geotextile with an
overlying medium rounded sand layer. Different soil types, the
existence of operation's layers or working surfaces, etc., will all
influence the leachate flow regime and have different implications„
Thus site-specific modeling of the intended cross section should be
undertaken. This paper has given a experimental method and procedure
to accomplish this type of modeling. Regarding the use of
backflushing to relieve clogging of leachate filters it should be
cautioned that the removal system must be designed accordingly and
approval of this approach must be gained during the permitting
process. It should also be recogni2ed that the backflushing liquid,
if water, will add to the leachate quantity to be eventually treated
and is generally not desirable from an operations point of view. Thus
air (or nitrogen^ backflushing or vacuum withdrawal might be desirable
options. Both of these possibilities are currently being evaluated.
acknowledgements
This project is funded by the U.S. Environmental Protection Agency
under Project No. CR-0149S5-O2. Our sincere appreciation is extended
to the Agency and in particular our Project Officer# Robert E.
Landreth.
REFERENCES
Editor, Elsevier Applied Science Publ,, Vol, 1, Nos. 1 and 2,
1988,
Elsevier Applied Science, 1989.
13J Haliburtonf T, A. and Wood, P. D.t "Evaluation of l/.S, Army Corps
of Engineers Gradient Ratio Test for Geotextile Performance, "
Las Vegas, NV, Aug. 1~S, 1982, IFAI, pp. 91-101.
14J Halse, Y,, Koerner, R. M. and Lord, A. E., ''Filtration Properties
of Geotextilea Under Long Term Testing,
Hershey, PA, Apr. 1987, pp. 1-13.
(5 ] Williams, N, D. and Abruzakhm, M. A., *'Evaluat ion of
Geotextile/Soil Filtration Characteristics Using the Hydraulic
Conductivity Ratio Analysis,41 Journal of Geotextile an^
Geomembranea. Elsevier Applied Science Publ., Vol, 8, No. 1, 1989,
pp. 1-26.
[6] Ramfce, H.-G., "Consideration on the Construction and Maintenance
of Dewatering Systems for Domestic Trash Dumps," TROB7-0119,
translated from German by U.S. EPA, Cincinnati, Ohio, Nov. 1087,
(7 J Rios, N. and Gealt, M. h.t "Biological Growth in Landfill Leachate
Collection Systems,H in
Elsevier Applied Science Publ,r 1989, pp. 244-259,

-------
322 GEOSYNTHETIC TESTING FOR WASTE CONTAINMENT APPLICATIONS
[8] Koerner, G.R. and Koetner, R. M
Collection Systems," in
E1scvier applied Science Putal., 1989, pp. 260-277,
"Biological Clogging in leaehate
(9) Koutner, G, R, and Koarner, R. M., "Biological Clogging oC
Geotextiles Used as Landfill Filters; First Year Results," GRI
Report #3, Geoaynthetic Research Institute, Philadelphia, PA, June
27, 1909,
KOERNER AND KOERNER ON BIOLOGICAL ACTIVITY
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326 GEOSYNTHETtC TESTING FOfl WASTE CONTAINMENT APPLICATIONS
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FIG. 9 — Leachate permeability response from all six landfills under
four conditions for nonwover. hast set geotextiles .
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keachate permeability response from ali Six landfills under
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334
GEOSYNTHETIC TESTING FOR WASTE CONTAINMENT APPLICATIONS
1 i
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a) Hypothetical Leachate Backflush (or Flow Remediation
BIOCIDE
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b) Hypothetical Leachate Backflush with Biocide
(or Flow Remediation
FIG. 12 -
Anticipated flow patterns after repeated backflushing
trials vith leachate (upper curve) and with biocide treated
leachate (lower curve).
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TECHNICAL REPORT DATA
(Please read Instructions on the reverts before compleir
1. REPORT NO. 2.
EPA/600/A-92/053
3.
4, TjTLE ANDSUBTITLE
Biological Activity and Potential Remediation
Involving Geotextile Landfill Leachate Filters
5. REPOHT DATE
S. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
George R. Koerner and Robert M. Koerner
8. PERFORMING ORGANIZATION REPOHT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Drexel University
Geosynthetic Research Institute
33rd & Lancaster
Building 10, West Wing, Philadelphia, PA 19104
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
CR818565
12. SPONSORING AGENCY NAME AND ADDRESS
Risk Reduction Engineering Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
r-i nri nnati DH
13.	TYPE OF REPORT AND PERIOD COVERED
Journal Article
14.	SPONSORING AGENCY CODE
EPA/600/14
15. SUPPLEMENTARY NOTES
Robert E. Landreth (513) 569-7871 (FTS) 684-7871
16. ABSTRACT . ,
•This paper presents the results of a biological growth study in geotextile filters used in landfill leachate
collection systems. After reviewing the first year's activity, a completely new experimental approach has been taken.
Using 100 Tim diameter columns for the experimental incubation and flow systems, the effects of six landfill leachates
are evaluated. Aerobic and anaerobic states, four different geotextiles, and soil/no soil conditions above the
geotextiles are involved 1n the testing program. This results 1n 96 individual test columns. Flow data is measured
regularly, and over the first six months of evaluation the fallowing trends have been observed.
•	no clogging (0% - 25% flow reduction) ' •
6 of 96 columns = 7% ,
¦ minor clogging (25% - 50% flow reduction)
4 of 96 columns =4%
•	moderate clogging (50%- 75% flow reduction)
37 of 96 columns = 38%
•	major clogging (75% - 95% flow reduction)
35 of 96 columns = 36%
•	severe clogging (95% - 100% flaw reduction)
. 14 of 96 columns = 15%
For two of the landfill leachates, backflushing has been attempted so as to reinstitute flow. This procedure works
well for the geotextile alone while not as well for the geotextile/soi1 columns. The exception is the nonwoven heat
set geotextile. All tests are still ongoing and will be dismantled and further investigated at the end of 12 months
exposure time. The experimental setup and procedure has been written up as a tentative ASTM test method and is
currently in task group review. , ,
17. KEY WORDS AND DOCUMENT ANALYSIS
B. DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
c. COSATt Field/Group
1eaching
biological clogging,
aerobic, anaerobic, soil
clogging, geotextile
clogging, leaching,
bacteria count, viable
count

18. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (This Report I
Unclassified
21. NO. OF PAGES
24
20, SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (Re*. 4-77) previous edition is obsolete
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