United States
                   Environmental Protection
                   Agency	     	
Hazardous Waste Engineering
Research Laboratory
Cincinnati, OH 45268
                   Research and Development
EPA/600/S2-88/040 Aug. 1988
&EPA         Project Summary
                   Loading  Point Puncturability
                   Analysis  of  Geosynthetic  Liner
                   Materials

                   Daren L. Laine, Michael P.  Miklas, Jr., and Charles H. Parr
                      Geomembrane liner performance
                  was examined in  laboratory  tests
                  subjecting polyvinyl chloride (PVC),
                  chlorosulfonated polyethylene
                  (CSPE), and  high density  poly-
                  ethylene  (HOPE)  materials, in two
                  thicknesses each,  to varying  pres-
                  sures, temperatures, and point loads.
                  Loads were induced by placing the
                  geomembrane  material over  trun-
                  cated rigid epoxy  cones  used as
                  loading points for 9.5,  19.0, and 24.5
                  mm heights  above the  sand
                  subgrade while arranged in three-
                  cone clusters  and applying a hy-
                  drostatic load to the top side of the
                  liner. Constant  hydrostatic loads of
                  17.93 kPa at 23°C  and 50°C  were
                  applied during a  one-year  test.
                  HOPE material measuring 1.5 mm
                  thick failed for the loading  point
                  height  of  25.4  mm  above the
                  subgrade. After 365 days, the load-
                  ing pressure was  increased  to 60.03
                  kPa for  an additional  30 days.
                  Failures were  induced in  1.5-mm
                  HOPE for loading point heights of
                  19.0 and 25.4  mm  and in  2.5-mm
                  HOPE for loading point heights of
                  25.4 mm. HOPE with a  thickness of
                  1.5-mm failed  for a loading  point
                  height  of 19.0  mm with  a  1.5-mm
                  geotextile placed between the  HOPE
                  and the loading point  at 17.94-kPa
                  pressure  and ambient  temperature.
                  HOPE with a thickness of  2.5 mm
                  overlaying  a  3.8-mm geotextile
                  failed under 60.03-kPa  pressure for
                  a 25.4-mm loading height at the high
                  temperature  test  condition. No
                  materials failed  when overlaid upon a
                  5.3-mm  geotextile.  Transient
pressure loading  test  without
geotextile support exhibited failures
caused by the maximum  pressure
load attained.
    The test results indicate  that
moderate economic benefit may be
gained by allowing particles project-
ing up to 25.4  mm  above  the
subgrade to remain in a finished
surface. Finished installation cost
reductions of up  to 28 percent per
hectare could result if the largest
particles in the subgrade  were
comparable with  the  tested sizes.
Geomembrane material  performance
was improved with the addition of
geotextiles,  indicating  a positive
cost-benefit advantage  when a ge-
otextile underlay is used.
    This  Project Summary  was
developed by EPA's Hazardous Waste
Engineering  Research Laboratory,
Cincinnati,  OH,  to announce  key
findings of the research project that is
fully documented in a separate report
of the same title (see Project Report
ordering information at back).

Introduction
    Geosynthetic materials are used to
provide reinforcement, drainage, filtration,
or liquid migration barriers as a part of
geotechnical engineering  projects.  A
geomembrane is  a class of geosynthetic
material composed of an impervious
synthetic polymer, elastomer, or
plastomer placed as a liner in landfills or
surface impoundments to  prevent the
migration of  primary or secondary
leachates into the ground. Many of these
geomembrane  materials  can  be
purchased either unremforced or

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reinforced  with  scrim.  The  typical
thickness  range of  geomembrane
materials is from 0.5 mm (20 mils) to 3.1
mm (120 mils).
    One of the most important factors for
liner performance is the quality  and
stability  of the supporting  subgrade over
which the  geomembrane is installed.
Because geomembranes  are  not
designed  to  directly  support  the
overburden load caused by water, soil, or
solid-waste  material placed on the liner,
the nature of the liner  subgrade becomes
extremely critical. Knowledge   of the
interactions between  the  geomembrane
and the subgrade is vital to the design of
waste storage installations. This technical
report is in direct  response to SHWRD
program  objectives  to understand
geomembrane performance  in  service
environments  and the related   factors
which may  cause liner  failure.  The
results of this testing program  provide
valuable   data  for  specifying
geomembrane  installations  for solid-
and  liquid-waste disposal  facilities and
suggest economic guidelines for geo-
membranes, geocomposites,  and sub-
grade preparation.

Research  Approach  and
Procedures
    The  objectives  of  this  research
program  were: (1)  to develop an under-
standing of  the  interactions between
geosynthetic materials and  the sup-
porting subgrade  in order to  determine
what  factors may lead  to  premature
and/or long-term  geomembrane  fail-
ures; and (2) to determine the economic
benefits  of alternative  liner installations
for landfills  or surface impoundments
which may lead to technical  guidelines
for the specification of the geosynthetic
materials and subgrade  preparation
requirements.

Preliminary Tests
    Preliminary tests were performed to
select the design and  shape  of  the
loading  points to  be  used  in  this
program.  The  criteria for  selecting  a
given load point design were:
  (1)  Load point represented natural load
      points in texture and angularity;
  (2)  Load   point  had  an   easily
      reproducible shape;  and
  (3)  Load point failed geomembranes at
      a  fifty percent  failure rate  in pre-
      tests.
Figure 1 shows a  detailed cross-section
design of the load  point that was  used in
this testing program.
    In addition to selecting  the  loading
point design,  tests were conducted to
select the initial test  conditions which
would  simulate  worst-case  field
conditions,  including  pressure loading,
temperature, and the  height above  the
plane of the  subgrade  that the load
points protrude.  A  test matrix  was
developed and approved.
    To ensure that the materials tested
in  this program  met  or  exceeded  the
physical  property  specifications  stated
by their  manufacturers,  ASTM physical
property  tests  were conducted on each
of  the subject geomembrane materials.
Table 1 lists the ASTM physical property
tests  that were  used  to  evaluate  the
geomembrane  materials.

Test Equipment
    Long-term hydrostatic  puncture-
resistance tests were conducted on PVC,
CSPE,   and  HOPE  geomembrane
material,  using two different thicknesses
for each type of material. These tests
were  conducted  in  36  round  plastic
pressure test vessels.  The vessels were
capable of withstanding pressures of up
to  103.5 kPa (15 psig) and temperatures
of  50°C  (123°F).  Figure 2  shows  the
design detail of the pressure test vessel.
A  pressure-regulated  nitrogen-over-
water system  was used  to  force  the
geomembrane  material onto a supporting
sand subgrade. Eighteen of the pressure
test  vessels  were  connected  to  a
closed-loop  hot  water circulating
system for elevated temperature testing.
Three artificial  load points were placed in
each test vessel  to simulate an irregular
subgrade surface. The 36  pressure
13.20cm
                   -8.25 cm -
Figure 1.
Cross-section of the conical
loading point.
vessels were monitored for temperatu
pressure, and geomembrane  failure.
constant  pressure was maintained
each of the  test  vessels by 2 two-sta
pressure  regulators  connected to
17,180-kPa  (2,460-psi)  nitrogen g
bottle. Individual  vessel temperature v\
measured by  dedicated thermocoup
wired to a  rotary-style  thermocouj
switch.  Temperature  readings  we
manually  recorded at periodic interv
from a digital display located on  t
temperature  controller box. Leaks  in 1
liner test specimens  were detected
magnetic float switches located  at  t
base of each pressure  vessel.  Thirty-
indicator lights, mounted  on ti
temperature  controller unit, were wired
the individual magnetic float switches. I
leak occurred in the geomembrane, wal
would flow through the hole and  woi
accumulate,  activating  the float  swit
and indicator light. Approximately  10
of water  were required to activate  tl
switch and indicator light. Daily logs we
recorded  for each of the 36 pressure te
vessels.

Economic Analysis
    Cost  data were collected on each
the three  types  of polymeric  materic
tested  and  on  three  thicknesses
geotextiles.  The  majority of cost da
were collected by telephone  interviev
with specialists  involved on  a day-t
day basis  with geomembrane tin
installation estimates.  Publications we
used  primarily   for  verification ar
corroboration.
    The  cost  data  were  used
conjunction with the pressure test data
establish the relative expenses  fi
installing  the different types of materia
over differing subgrades.  Charts ar
tables were  created to  present the da
with clarity  The  analysis results provic
a  comparison of the costs  associate
with different combinations  of lin<
materials and subgrade conditions.
matrix was  developed  to facilitate co
comparisons between the various lin<
combinations and subgrade finishes.

Results and Discussions
    Laboratory tests  were conducted
determine  the failure  mechanisms  <
geomembrane materials placed over i
irregular  subgrade and  subjected to
constant hydrostatic load of 17.93 kPa fi
365 days. The  failures  during the lov
pressure  tests are shown in Table  2. Tr
1 5-mm  (60-mil) HOPE  was  the onl
tested  synthetic  material to  fail  to th
limit of  water leakage  in less  than  36
days when subjected  to hydrostatic loac

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             Table 1. ASTM Tests on Subject Geomembrane Material
Properly
Specific gravity
Tear strength
Tensile properties including
breaking factor
Hydrostatic resistance
Puncture resistance
FML material
HOPE (1.5 mm & 2.5 mm)
PVC (0.5 mm & 1.0 mm)
HOPE (1.5 mm & 2.5 mm)
PVC (0.5 mm & 1.0 mm)
CSPE (0.9 mm & 1.1 mm)
PVC (0.5 mm & 1.0 mm)
HOPE (1.5 mm & 2.5 mm)
CSPE (0 9 mm & 1. 1 mm)
HOPE, PVC, and CSPE
(2 thicknesses each)
HOPE, PVC, and CSPE
(2 thicknesses each)
ASTM test
D792, Method A
0792, Method A
01 004, Die C
D751, Method Ba
D882, Method A or B
0638
075), Method Ab
075? (Mullen)
FTMS 101C,
Method 2065
Temperature °C
23
23
23, 50
23, 50
23, 50
23, 50
23, 50
23
23, 50
             a With 8-in. x 8-m. test specimens.
             b Grab method
of 17.94 kPa (2.6 psig) with load point
heights  of 25.40 mm  (1 0 in.). The 1.5-
mm  (60-mil)  HOPE material failed after     (2)
148 days of continuous testing at  17.93
kPa (2.6 psig).  Figure  3 shows  Sample
13, 1.5-mm  HOPE, which  failed. For
verification  purposes,  another  specimen
of 1 5-mm  HOPE was  tested and  failed     (3)
after 60 days at ambient temperature,
1794 kPa, and  25.4-mm load  height.
The failed verification sample is shown in     (4)
Figure 4.
    Polyethylene is   one  of  several
plastics  which exhibit  a marked  plastic
flow  and necking  at  high  load levels.
Under   some conditions,  the  failure
elongation is  more than ten times  (1000     (5)
percent  strain).
    In the  prominent  failure of  1.5-mm
HOPE,   Sample  No.  13,  the  following
interpreted sequence of events  occurred:
(1)  As the  sheet was  pressed down on
    the  cone, a general stretching of the     (6)
    material  occurred  within  a  radial
                                            distance of approximately 50.8 mm
                                            around the cone.
                                            Near  the apex, a localized  stress
                                            concentration caused elongation  of
                                            the polyethylene into  the necking
                                            region of behavior in the direction of
                                            the line of symmetry of the cone.
                                            At this  stage, the elongation in the
                                            direction perpendicular to the line of
                                            symmetry remained small.
                                            The  elongation continued  until
                                            necking ended. At this point, the wall
                                            had thinned to about 0.25 mm. This
                                            corresponds  with a  strain  of  about
                                            550 percent if the lateral strains are
                                            still small.
                                            Because of the flow  during necking,
                                            considerable  alignment  of  polymer
                                            chains  caused  stiffening,  which
                                            strengthened  the polymer in the flow
                                            direction but reduced the  polymer
                                            strength in the transverse direction.
                                            Continued downward tension  over
                                            the cone increased  the  elongation
        Water
        Outlet
                 Thermocouple -
                    Air ^
                  In/Out
                                  50. SO cm
                                              Air Pressure
                                                 Gauge
                                                            ABS Vessel
                                                            Water
                                                            Inlet
  25.40cm
                                                                 Double
                                                                Neoprene
                                                                 Gaskets

                                                                Geomembrane
                                                                Specimen
           Fine Sand -
                         Cone
                        35° W/
                     45° Truncation
                         at Top
                                               Drain Valve    ~*BS Vessel
                                  - Float Switch

Figure 2.   Cross-section drawing of the hydrostatic pressure vessel.
    and  stress  in  the  transverse
    direction.  Because  the  strength  in
    this  direction was  compromised,
    fractures occurred.
    This  failure  mode  is  a complex
process  involving a nonlinear thermo-
viscoelastic material with an intricate
loading  history.  Loading  conditions
changed from  stress-type  to dis-
placement-type loading  during the test.
The  stress and  displacement fields are
two-dimensional  and vary with time  in
each  direction. The  failure  of the  1.5-
mm HOPE appears to be a normal failure
in that the loading simply extended the
material  beyond  its capability.
Characteristically, materials  which are
biaxially stressed fail  at strain  levels
considerably lower than  the failure strain
limit  in  uniaxial tests. SEM  examination
confirmed  that  the   1.5-mm  HOPE
experienced a  simple  overload  failure
caused by the  stress concentration at the
apex of the point loading cone.
    The thickness of  the  unstressed
portions  of  the  HOPE  test   specimens
were  found to  vary significantly.  Six
thickness readings on  Sample No.  13
varied from 1.40 mm to 1.62 mm, with an
average thickness of  1.47  mm. The
thickness of Sample No. 15  varied from
1.47  mm to 1.70 mm, with an average  of
1.65  mm. Commercial  sheeting  of the
type  tested has  a specified  thickness
tolerance of 10 percent  or, in this case,
0.15  mm, so that, except for one point,
the sheets were  within  tolerance. Note,
however, that the bending stiffness of the
sheet  varies  with  the cube of  the
thickness. Therefore, based  upon the
measured average thicknesses, Sample
No. 15 is 40 percent stiffer than Sample
No. 13.  This relative increase in stiffness
may explain why Sample No.  15 failed  to
a lesser extent than Sample No. 13, even
though the test temperature  was higher.

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Mate
Type
HOPE
HOPE
HOPE
trial
mm
1.5
1.5
1.5
Sample GeofexMe
No. mm
24
15
13
Temp.
"C
23
23
50
Press.
kPa
17.94
17.94
17.94
Time
days
60
148
148
Load height
mm
25.40
25.40
25.40
Obviously,  this thickness  variation is a
real-world  effect  and  must   be
considered when assessing the behavior
of geomembrane liners.
    In addition to the failures  displayed
by  the  HOPE material, partial failures
were noted in the 0.9-mm and 1.1-mm
CSPE tested  at  17.94 kPa for 155  day
with load  point heights  of 25.4 mm. A
partial failure  is defined  as a failure  that
does not compromise the capacity of the
liner material to  prevent  water flow
through  the membrane to  the  subgrade.
After the partial failures  were noted,  the
hydrostatic   pressure  tests  were
continued  for an additional 210 days. At
the end of  this  testing  period,  the
pressure was increased  to 60.03 kPa for
an additional 30 days of testing.
    A microscopic  study  was  made  of
the partial failure area of Sample No. 64,
which was 1.1-mm  CSPE material  with
scrim reinforcement. The scrim is made
from  rugged  10 x  10  1000  denier
polyester  yarn. The  partial  failure  was
directly over one  of the load points that
was 25.4  mm above the subgrade, and
the material  had been  stressed  to a
maximum  pressure of 60.03 kPa for 30
days, resulting in tearing of the lower
side  of the sheet  and  scrim  breakage in
two places. The  breakage is  shown  in
Figure 5. Note the buckled shape of the
entire area, indicating  that the CSPE
and/or scrim had been stretched beyond
its elastic  limit. Figure 6 shows a close-
up view of the broken fiber shown on the
right in Figure 5. The fiber break itself is
unremarkable, but the striated  area
above it,  which appears to be almost
fibrous in   nature, is  a  lineation which
commonly occurs in plastic flow areas of
 Figure 3.    SEM of failure (21X); Sample No. 13 1.5-mm HOPE.
             Note: Striations (A) and edge of drawn region IB).
polymers. A  photograph  of  the s
pattern  is  shown  in  Figure 7
roughened appearance  of the  C
surface  directly  above the  fibers
indicate that the CSPE and scrim \
stretched beyond the elastic limit of
CSPE material. After  removal of the I
the fibers  snapped  back,  putting
plastically  deformed  CSPE  i
compression. This compression  rest
in local buckling of the CSPE. The C
material was overstressed  whe
hydrostatic load of 17.94 kPa was apr.
to  the material  over a  25.4-mm I
point. The applied force caused the Ic
CSPE material  layers  to  tear  and
internal scrim to break.
    At the completion  of 365  day;
low-pressure testing,  the  hydrost
pressure was increased at a rate of
kPa per  hour until a pressure  of 61
kPa  was achieved.  This  test  press
was maintained constant for an additi
30 days.  The materials  that failed
high-pressure testing are listed in T;
3. The results of these tests indicate
the HOPE  1 5-mm and  HOPE  2.5-
materials failed at 23°C  and  50°C
cone heights of  19.0 mm and 25.4
above the  subgrade.  As previoi
discussed for other field  samples,  th
failures  are normal events in which
material was stressed beyond its ela
limit until failure occurred.
    Of  particular  interest  during
accelerated high-pressure tests  was
accumulation of  excessive water in
pressure test vessel containing Sanr
No. 76,  PVC 0.5-mm, at 23°C witl
cone height of 19.0  mm.  The excess
water accumulation  led  to  speculai
that the PVC liner material had leaks,
a  casual inspection  of the  mate
identified no apparent punctures.
    Only after an  intense  inspection w
five  pin-size  holes found.  These  he
could only be seen when  an intense I
source cast illumination  directly ber
the hole. The holes were located near
edges of the sheet and not near the o
points;  therefore, the areas  were
highly stressed.  It is suggested that

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  Figure  4.    View of verification test failure on HDP£ 1.5-mm Sample No. 24.
holes might have  been  manufacturing
imperfections in the  sheet.  Additional
visual  inspection  of  the  entire  liner
surface revealed three rows of pits in the
surface of the sheet. These pits reduced
the load-carrying  capacity  of  the  PVC
membrane. However,  there  was no
evidence found during optical or SEM
inspection that there was any connection
between  these pits  in the material and
the pinhole failures.
    Transient  pressure  loading tests
were conducted by placing new samples
of geomembrane  material into the test
 Figure S.    Scrim breakage on 1.1 -mm CSPE after loading at 25.4 mm (W2X).
vessels and applying pressure at a rate
of 55.2 kPa per hour until the final test
pressure of 60.03 kPa was achieved. The
final pressure of 60.03 kPa was  held
constant for 24 hours. Load point heights
of 25.4 mm, 19.0 mm, and 9.5 mm were
used  at   ambient-  and  high-tem-
perature exposures.
    The  results of  these  transient
pressure loading tests are presented in
Table 4. The CSPE 1.1-mm and HOPE
1.5-mm materials failed  the test at  a
pressure of 60.03 kPa  with  a loading
point  height  of  25.4  mm  and  a
temperature of 50°C. Figure 8 shows the
failure  of  the 1.1-mm  CSPE material,
and  Figure 9 shows the failure of  the
1.5-mm HOPE  material.
    The  HOPE 2.5-mm material  failed
at a temperature of 23°C  at the  final
pressure of 60.03 kPa and a loading point
height  of 25.4 mm and is shown m Figure
10. Examination of the failure areas with
an optical microscope indicated that the
failures were normal,  resulting from
overstressmg  the geomembrane material
in the region of the point load.
    Tests using geotextile materials were
conducted  to evaluate  the mechanical
advantages  of  a  composite  liner
configuration versus a geomembrane
liner  material  without  a  protective
underlining  of  geotextile material.  A
typical  composite liner was modeled by
placing the geotextile material  between
the load points  and the geomembrane
material.  Those geomembranes which
failed the short-term tests, accelerated
tests, and  the  impact load  tests were
used in this test sequence. Continuous-
filament  polyester  nonwoven  needle-
punched geotextiles having thicknesses
of 1.5 mm (60 mil), 3.8 mm (150 mil), and
5.8 mm (230 mil) were tested. Woven
geotextiles were not evaluated  because
of their  limited use  in current liner
installation  practice. The geomembrane
materials  tested  were  HOPE  1.5-mm,
HOPE  2.5-mm,  CSPE  1.1-mm,  and
CSPE  0.09-mm. Testing was  conducted
at 23 °C and  50 °C for a cone height of
25.4 mm.
    The results of the composite material
tests are presented  in Table 5.  Tests at
ambient  temperature on  the  1.5-mm
HOPE  liner material combined with  a
1.5-mm geotextile at 60.03 kPa caused
failure  to occur at 210 days. The HOPE
2.5-mm material combined with a 3.8-
mm geotextile failed at 50°C and 60.08
kPa after 60 days of testing. The failure
mode of the HOPE, in both cases, was a
normal failure caused by over-stress on
the liner material at the loading point.

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  Figure 6.    Close-up of broken scrim fibers 1.5 mm CSPE (SOX)
    The CSPE material did not fail when
a geotextile was  placed between the
membrane and the load points, and there
was  no evidence of  scrim  separation
such as that  observed in test samples
tested  without  a  protective  geotextile
material.
    Tables  6  and  7  illustrate  the
probable  costs associated  with  the
installation of tested geomembranes and
geotextile materials.  Based  upon the
pressure loading  test results,  certain
composite combination  costs are not
listed  because the  subject liner material
  Figure 7.   Close-up of scrim pattern; 1.1 -mm CSPE (11.5X).
failed under the given  situations stal
(Example:  HOPE  material of  1.5-1
thickness should  not  be  used  or
subgrade  in which  particles  exceec
height of 3.5 mm above the plane of
iubgrade preparation to varying level:
fineness based on the maximum size;
particles  which are allowed  to remair
the surface plane of the  subgrade.
    It is  not recommended that  any
the liner installation options be utilizec
lieu  of  others  based  solely  on  c
considerations. The cost  figures
intended to quickly convey  exper
information concerning each option wl
providing the  reader with  the  relal
confidence offered by an appropri
subgrade finish.  A given site  nr
"require" only a 0.5-mm PVC  mate
thickness over a  25.4-mm  or  It
irregular  subgrade,  based  on the t
results and economic analysis; howev
an economically astute owner might el
to use a 3.8-mm geotextile at  a gi\
facility  and/or a  finer  finish  of i
subgrade. The geotextile would make
liner  system more secure and safe  fr
larger  particle  penetration  by  piec
which,  though  absent from the mitic
prepared surface, might work their v
upwards  through the subgrade  A  fn
finish than  25.4-mm particle  project
would reduce the  ultimate  potential
penetration and cause subsequent faili
during the anticipated lengthy (usually
years or more) life of the facility

Conclusions and
Recommendations
    Geocomposites  (geomembrane p
geotextile) have a mechanical advantc
in improved  performance  over  g«
membranes  alone  The  econonr
advantage of using a composite syst<
is associated  with  the improved  p
formance of the geomembrane in  p
venting  a  costly  waste  clean-
operation.
    Further  long-term   testing
required to  evaluate the  minimi
subgrade bedding  requirements I
geosynthetic liners.  New  tests  shoi
emphasize investigations of  polyethyle
material and should incorporate testing
geomembranes  over  other types
irregular surfaces
    Geognds   are  synthetic,  ope
weave, high-flow capacity drainage m
that  are   placed   between  tv
geomembranes  to  provide mcreas
drainage capacity   in  double-liner
stallations. Geognds are used in place
traditional natural drainage materials su
as sand  or gravel  and are  being  us
more widely in the liner  industry;  thi

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           Table 3.     High Pressure Failure Data on Prestressed Geomembrane
Material
Type
HOPE
HOPE
HOPE
HOPE
mm
1.5
1.5
2.5
2.5
Sample Geotext/le
No. mm
6
17
39
32
Temp
°C
23
50
50
23
Press.
kPa
60.03
60.03
6003
6003
Time
days
30
30
30
30
Load height
mm
19.00
19.00
1900
2540
they should be included in future testing
of synthetic liner configurations.
    Frequently,  high  density  polythene
material is used in the construction  of
brine  storage  impoundments  and
experimental solar ponds  for electrical
power generation.  In  both  of these
applications,  elevated temperatures  of
greater than  95°C  are  encountered.
Therefore,  geomembrane  testing should
be extended to include temperature tests
to at least  95°C.
    Additional tests should be devised to
provide  insight into the  relationship
between laboratory  loading  point
geometries and natural loading points for
more  realistic failure analysis studies.
Short-term  high-pressure  testing, us-
ing various loading  point shapes,  should
be  done and the results compared with
tests  using  natural  loading  points  to
establish  practical  differences  on the
mechanics of liner failure."
    Figure 8.    Failed CSPE 1.1 -mm for 25.4-mm loading point.

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          Table 4
Transient Pressure Loading Failure Data
                Material
             Type
           Sample      Geotextile       Temp.       Press.        Time          Load height
            No.	mm	°C	kPa	days	mm
            CSPE


            HOPE


            HOPE
 1.1


 1.5


 2.5
91


12


25
50


50


23
60.03


60.03


60.03
                                                                                25.40
25.40
                                         25.40
Figure  9.    Failed 1.5-mm HLDPE for 25.4-mm loading point.
 Figure  10.    Failed HOPE 2.5-mm for 25 4-mm loading point.

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Material Samole
Type
HOPE
HOPE
Table 6.
mm No.
1.5 <
2.5 40*
Installation Cost Matrix for
Materials including
normal cost to install -
for one hectare in unit
quantity
Geotextile Temp.
mm °C
1.5 23
3.8 50
Press. Time
kPa days
60.03 210
60.03 60
Tested Liners and Geotextiles (Costs in $1,000'S)
Subgrade with up to 25.4 Subgrade with up to 19.0
mm projection above mm projection above
plane installed plane installed
Least Confidence
Pond Depth in Meters to

Pond Depth in Meters to
Load height
mm
2540
25.40
Subgrade with up to 9.5
mm protection above
plane installed
Greatest Confidence
Pond Depth in Meters to
 Material (mm)     1 hec    100 hec
             1.8
                         6.1
                                     1.8
                                                 6 1
1.8
                                                                        6.1
CSPE 0.9
W 1.5 GEO
38 GEO
5.3 GEO
CSPE 1 1
W 1.5 GEO
3.8 GEO
53 GEO
PVC 0.5
W 1 5 GEO
3.8 GEO
5 3 GEO
PVC 1 0
W 1.5 GEO
3.8 GEO
5.3 GEO
HOPE 1 5
W 1 5 GEO
38 GEO
5.3 GEO
HDPE 2.5
W 1 5 GEO
3.8 GEO
5.3 GEO
82
97
99
106
91
106
109
116
32
42
49
57
52
59
69
77
82
91
99
106
94
106
111
119
59
67
72
79
69
77
82
89
22
32
35
42
37
42
49
57
54
62
67
74
62
67
74
94
10.4
10.4
10.4
104
10.4
10.4
10.4
10.4
10.4
10.4
10.4
10.4
104
104
10.4
104
NR
104
10.4
10.4
10.4
W 4
104
104
10.4
10.4
10.4
10.4
NR'
10.4
10.4
10.4
10.4
10.4
10.4
10.4
10.4
10.4
10.4
10.4
NR"
NR
10.4
104
NR"
10.4
NR
10.4
16.1
16.1
16.1
16.1
16.1
16.1
16 1
161
16.1
16.1
16.1
161
16.1
16.1
16.1
16 1
16.1
16.1
16.1
16.1
16.1
16 1
16.1
16 1
16.1
16.1
16.1
16.1
16.1
16.1
16.1
16.1
16.1
16.1
16.1
16.1
16.1
16.1
16 1
16.1
NR
16.1
16.1
16.1
16.1
16 1
16.1
16.1
19.5
19.5
19.5
195
19.5
19.5
19.5
19.5
19.5
19.5
19.5
195
19.5
195
195
19.5
19.5
19.5
19.5
195
195
19.5
19.5
19.5
19.5
19.5
19.5
195
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
19.5
NR  Not Recommended, liner
NR* Not Recommended: liner
NR" Not Recommended: liner
W  With geotextile.
and/or geotextile/lmer combination failed at these conditions
failed impact loading tests
failed both above.

-------
Table 7.   Probable Costs Associated with Composite Liner Installation
     Thousands of Dollars
 100 p

  90 E-

  80
                                                                  ••j wo
                                                                    Hectares
                                                                  • One
                                                                    Hectare
    PVC
05

 PVC

  Material MM
                HOPE
                1.0
1.5   CSPE   1 1   GEO    1.5   GEO
CSPE 0.9    HOPE  25    GEO  3.8
53
  Daren L Laine, Michael P. Miklas, Jr., and Charles H. Parr are with Southwest
       Research Institute, San Antonio, TX, 78284.
  Charles J. Moench is the EPA Project Officer (see below).
  The  complete report,  entitled "Loading Point Pun durability  Analysis of
       Geosynthetic Liner  Materials," (Order No. PB  88-235 544/AS; Cost:
       $19.95, subject to change) will be available only from:
           National Technical Information Service
           5285 Port Royal Road
           Springfield,  VA 22161
           Telephone:  703-487-4650
  The EPA Project Officer can be contacted at:
           Hazardous Waste Engineering Research Laboratory
           U.S. Environmental Protection Agency
           Cincinnati, OH 45268
                                                          10

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