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Bloomington Project Landfill - RCRA
Landfill Permit Application
(August 1991) - Document
Review - Pertaining mostly to
the El Section, Hydrogeologic
Site Characterization Report.
Proposed Bottom Road Site
by
Gareth J. Davies, M.Sc., P.G.
Principal Hydrogeologist,
Cambrian Ground Water Co.
109 Dixie Lane, Oak Ridge, TN 37830
Introduction
All readers of this review should become familiar with both the literature
that is cited in addition to other relevant literature. Only then can the
necessity and validity of the comments that are made in this report be appreciated.
Refutation of comments made in this review should also be backed by references
or otherwise cited literature.
The American Society for Testing and Materials (ASTM) standards and guides
that are referenced in this review are not only peer-reviewed manuscripts
accepted for publication by professionals from the scientific community,
they are carefully written documents written and supported by the consensus
of the membership of ASTM, whose members are comprised of a broad spectrum
of professionals from academia, industry, the federal and state government
system and the environmental consulting industry.
This review makes most of its comments on one aspect of this report: the
type of investigation that was conducted and its potential usefulness in
relation to permitting this site for purposes of land filling activities.
In the Introduction section of the permit application describes the hydrogeologic
investigation as "extensive."
Despite being claimed to be extensive, the investigation describcd in the
permit application does not follow guidelines presented in an Quinlan (1990)
Special Technical Publication (STP) that was published a year before the
study was done. That STP states that there could be a need for groundwater
tracing to be done at sites such as this. In later publications by ASTM
and U.S. Environmental Protection Agency, it is also said that ground-water
tracing might need to be done at sites such as this. During 1991 [the year
this study was done] U.S.EPA was actively endorsing the use of ground-water
tracing at sites where data from wells alone might not be adequate for characterization
of a site (USEPA, 1991, 1991b).
The site is underlain by, in part a fractured-rock aquifer, and also in
part a carbonate aquifer or possibly a karstic aquifer, each of which would
have a high probability of having preferential-flow zones. The carbonate
rocks that crop out in the vicinity of the site and might underlie the site
are not described in the report as karstic, but it is practicably impossible
to detect such karstic conditions by using the methods that have been used.
Alternative investigative methods for such aquifers and fractured-rock aquifers
are recommended by ASTM, U.S.EPA and is implicit in the scientific literature.
It is acknowledged by ASTM (1996) that in karst and fractured-rock aquifers,
there is preferential flow, rapid flow, and subsequent underestimation of
the flux and transport of contaminants if inappropriate investigative techniques
are used. Even if the site is underlain by only a non-carbonate fractured-rock
aquifer hydrologic conditions would necessitate adopting specific applicable
techniques to understand the groundwater system and characterize the site
(ASTM 1996).
A hypothesis that any aquifer behaves as a porous medium, where the implicit
assumption can be made that devices such as wells can be used to characterize
ground-water conditions, depends upon whether or not there are preferential-flow
paths, or whether or not ground-water velocities are rapid enough to sustain
turbulent flow. If there are preferential, rapid, turbulent flow paths test
methods such as pumping tests, slug tests or packer tests ultimately do
not yield reliable data about the maximum ground-water flow rate that could
exist (ASTM,1996). If the same hypothesis is tested at the Borden Aquifer,
Ontario, Canada, which is entirely a sand and gravel aquifer and would be
assumed to behave as a porous medium, the result is failure (Cherry, 1994).
If that aquifer fails then more complicated aquifers (karst, carbonate,
and fractured-rock aquifers) would all be expected to fail. Professionals
of ASTM came to their own similar conclusions when they proposed developing
a standard guide to designing groundwater monitoring systems in fractured-rock
aquifers of all forms, because they presented special problems (ASTM, 1996).
The issue of whether a given carbonate aquifer is karstic or not is an old
and ongoing discussion. However, it can be easily shown that major carbonate
aquifers that are not acknowledged as karstic by the hydrogeologic cognicentae
(the Chalk of Northwest Europe, and the Jurassic Great 0olite and Inferior
Oolite of Britain) have both preferential flow and rapid flow (Atkinson
and Smart, 1977, 1981; Atkinson and Smith, 1974). It is significant in each
case that rapid and preferential flow was only revealed when tracing was
done.
When installing wells, there is a very low probability of randomly (even
though the location of the well is chosen using best judgment) intersecting
macrofissures or conduits, intersecting zones of preferential flow.
To have 90% probability of intersecting a 1 -meter diameter circular subterranean
cavity by drilling it would require drilling more than 1000 3-centimeter
drill holes per acre (Benson and La Fountain, 1987). Another example is
provided by the Optimiskiceskaya Cave in the Ukraine, which contains the
densest conduit network known in the world, at least 180 kilometers of conduits
(these are the ones that have been found) exist in a aquifer that is contained
in an area of 1,600 square meters, and an aquifer thickness of 100 meters
(Courbon et al., 1989). However, in this aquifer, the calculated probability
of drilling into this network randomly from the surface is still only 12%
(Dr. Alexander Klimchouk, Ukraine Speleological Survey, personal communication,
1993).
Further, if it is hypothesized that if the aquifer that underlies this site
is characterized by slow, laminar flow (as suggested from the well data)
it would be expected that ground-water would have high hardness because
meteoric waters would not circulate rapidly enough to upset near saturated
conditions. Such is apparently not the case, data collected at the site
show that the aquifer underlying the site has relatively low hardnesses
implying that there is rapid circulation of meteoric waters. Using criteria
from ASTM (1996) Figure 1 shows clearly that all of the alkaline hardness
(CaCO3) values derived from samples collected from ground water beneath
the site are less than 500 mg/l, which as stated in ASTM (1996) is an indication
of rapid circulation of meteoric waters, rapid flow and "karstic"
conditions (rapid, preferential, and turbulent flow -- there is no other
feasible explanation), even though the rocks beneath the site might not
appear to have obviously karstic qualities. Figure 1 also shows that there
is considerable variability of hardnesses of ground-waters that underlie
the site.
There is fractured rock and possibly carbonate rock that underlies the site
of the proposed Bloomington Project Landfill. However, only monitoring wells
and porous media-type testing has been conducted, so all that can be said
with confidence is: that the site has been characterized using inappropriate
techniques and that little is known about rapid and preferential ground-water
flow that probably exists at the site. The investigation as done makes too
many assumptions about hydrogeologic conditions that might be invalid. These
invalid assumptions would leading to inappropriate characterization techniques
and resulting incorrect conclusions could result in serious consequences
for permitting a hazardous-waste landfill.
Even if the correct investigative technique is eventually adopted and performed,
good data, which are the basis for making good decisions have to be collected.
In particular, surface and groundwater data should be collected through
at least four seasons, at minimum the dry and wet seasons of statistically
"typical" years. Only then will it be known what are ground-water
conditions at the site, and only then can decisions be made about whether
the site is appropriate or not, and not before.
The following references are easily available and highly pertinent to the
hydrogeologic investigation of any site such as this, and are not referenced
in the permit application; of course some were not published when the work
was done:
Quinlan, J.F., Davies, G.J., Jones, S.W., and Huntoon, P.W.,
1996, The applicability of numerical models to adequately characterize ground-water
flow in karstic and other triple-porosity aquifers. Subsurface Fluid-How
(GroundWater) Modeling, ASTM STP 1288, J.D.Ritchey and J.O. Rumbaugh, American
Society for Testing and Materials, Philadelphia, PA. p. 114-133.
Quinlan, J.F., 1990, Special problems of ground-water monitoring in karst
terranes, Ground Water and Vadose Zone Monitoring, ASTM STP 1053, D.M. Nielsen,
and A.I. Johnson, Eds., American Society for Testing and Materials, Philadelphia,
PA, p. 856-876.
American Society for Testing and Materials, 1995, Standard guide for design
of ground-water monitoring systems in karst and fractured-rock aquifers,
ASTM Standard Guide D5717-95, Annual Book of ASTM Standards, Volume 04.09,
Soil and Rock (II), p. 435-451.
The following documents are other references that specifically refer to
special techniques for reliable ground-water monitoring in carbonates.
U.S. Environmental Protection Agency, 1989, Test Methods for
Evaluating Solid Wastes, SW846, Third. ed. Office of Solid Waste and Emergency
Response, U.S. Environmental Protection Agency, Washington, D.C., Vols.
IA, IB, IC, and II. [This document was specifically modified to accommodate
karst, carbonate and fractured-rock aquifers.]
U.S. Environmental Protection Agency, 1991, "Notice of Proposed Rule-making
for Ground-Water Monitoring Constituents, (Phase II) and Methods Under Subtitle
C of the Resource Conservation and Recovery Act - ACTION MEMORANDUM,"
from Don Clay, Assistant Administrator for Solid Waste and Emergencv Response
to William K. Riley, Administrator, EPA). [This document specifically addresses
karst, carbonate and fractured-rock aquifers.]
U.S. Environmental Protection Agency, 1991b, "Proposed Modifications
to Title 40 CFR Part 264 -- Standards for Owners and Operators of Hazardous
Waste Treatment, Storage, and Disposal Facilities, " p. 2, 9 40-44
and 51-52. [This document specifically addresses karst, carbonate and fractured-rock
aquifers.]
The following are comments that refer to specific sections of the permit
application.
Section 1.4
The existence of 105 borings, 38 wells, and 68 test pits have no guarantee
that they have intersected the zones of preferential flow, which occur in
every aquifer (Quinlan et al., 1996, ASTM, 1996).
The layer underneath this is referred to as a clay, however there is no
reference made to macropores that riddle almost all clays and all such deposits.
The macropores are often not observed in field studies such as the digging
of test pits because they are often smeared shut during digging, drilling
or boring. Also, it should be considered that if clay-rich or clay soils
were really clays then they would not permit the percolation of any water
and this does not happen or the site would be a giant lake or raging torrent
of run-off water during every storm event, and continue to have many surface
streams even long after precipitation has ceased. Also a lack of permeability
in the soil would mean that nothing would grow. There are several "dry
valleys" in the vicinity of the site which shows that drainage is mostly
through the subsurface and proves that in the underlying aquifer there is
ample permeability.
This permeability is not reflected by the values of hydraulic conductivity
that have been measured at the site. This is also not surprising, as it
is widely acknowledged that the measurement method (i.e., scale of measurement)
used in hydraulic conductivity (k) determinations yields a related magnitude
of k (Clauser, 1990, Quinlan ct al., 1996, Bradbury and Muldoon, 1990).
It can be shown that the magnitude of k measured in allegedly non-karstic
rocks is the same order of magnitude of k that is measured in rocks that
contain
Mammoth Cave, Kentucky, the aquifer that contains the longest cave in the
world (Worthington et al.,, 1997).
There is an inconsistency in the report, where despite the fact that in
the descriptions of the test pits clearly state that the underlying bedrock
is often limestone, none of the illustrations in the body of the report
say that the site is underlain by anything other than siltstone.
Section 4.2.2
The potentiometric maps of the site show very clearly that there is a trough
in the water table that is aligned from northeast to southwest. This steeply-sided
trough in the potentionietric map of bedrock well data has a classic signature
of preferential flow in a macrofissure or conduit. There is no explanation
given for the trough that is obviously present in the data from the bedrock
wells. This trough could delineate a macrofissure that might transmit ground
water very rapidly toward the northwest. The cause of the deep trough must
be investigated before the permit is granted. The trough proves that hydrogeologic
conditions beneath the site are highly anisotropic and in itself is proof
that the conditions at the site do not approximate a porous medium. It is
also reported that there are vertical gradients at the site despite the
fact that the aquifer is described as "confined."
Presumably this a result of interpretation of the overlying clay-rich soil
an impermeable unit. This is rarely true of clay-rich soils as they are
riddled with macropores. All karst terranes are characterized by clay-rich
soils, composed of clays, degraded clays and sesquioxides (Jennings, 1985,
p. 35-36), but this rarely prevents rapid recharge through this soil. It
also produces a landscape similar to that in the vicinity of the landfill
site, many valleys, but very few with streams in them.
Summary
Despite the fact that a lot of work has been done in this permit application,
inappropriate techniques have been inadvertently been used that result in
an unrepresentative and unreliable characterization of the site. The techniques
that were used are almost sure to underestimate: the velocity of ground
water, the potential rate of migration of contaminants, the two most important
components. Current philosophy about characterization of such sites involves
a more rigorous approach to investigating ground-water so that when landfill
permits are granted groundwater and other precious resources in the hinterland
of the proposed site are protected as much as possible. The permit should
be denied based upon the current level of understanding shown in the permit
application.
References Cited
Atkinson, T.A., and Smart, P.L., 1977, Caves and Karst
of Southern England and South Wales, Guidebook for the International Congress
of Speleology, British Cave Research Association, 83 p.
Atkinson, T.A., and Smith, D.I., 1974, Rapid ground-water flow in fissures
in the chalk -an example from South Hampshire, Quarterly Journal of Engineering
Geology, v. 7, p. 197-205.
Bradbury K.R., and Muldoon, M.A., 1990, Hydraulic conductivity determination
in unlithified glacial and fluvial materials, Ground-water and Vadose-zone
Investigations, ASTM STP 1053, D.M. Nielsen, and A.l. Johnson, (eds) ASTM
Philadelphia, p. 138-151.
Cherry, J.A., 1994, Guest lecture, Geological Society of America Southeastern
Section Annual Meeting, Knoxville, Tennessee.
Clauser, C., Permeability of crystalline rocks, EOS v. 73., no. 21., May
26, 1992, p. 233, 237-238.
Jennings, J.A., 1985, Karst Geomorphology, Blackwell, 293 p.
Quinlan, J.F., Davies, G.J., Jones, S.W., and Huntoon, P.W., 1996, The applicability
of numerical models to adequately characterize ground-water flow in karstic
and other triple-porosity aquifers. Subsurface Fluid-Flow (Ground-Water)
Modeling, ASTM STP 1288, J.D.Ritchey and J.O. Rumbaugh, American Society
for Testing and Materials, Philadelphia, PA. p. 114-133.
U.S. Environmental Protection Agency, 1991, "Notice of Proposed Rule-making
for GroundWater Monitoring Constituents, (Phase II) and Methods Under Subtitle
C of the Resource Conservation and Recovery Act - ACTION MEMORANDUM,"
from Don Clay, Assistant Administrator for Solid Waste and Emergency Response
to William K. Riley, Administrator, EPA).
U.S. Environmental Protection Agency, 1991b, "Proposed Modifications
to Title 40 CFR Part 264 -- Standards for Owners and Operators of Hazardous
Waste Treatment, Storage, and Disposal Facilities, " p. 2, 9 40-44
and 51-52.
U.S. Environmental Protection Agency, 1989, Test Methods for Evaluating
Solid Wastes, SW846, Third. ed. Office of Solid Waste and Emergency Response,
U.S. Environmental Protection Agency, Washington, D.C., Vols. IA, IB and
II.
Worthington, S.R.H., Davies, G.J., and Ford D.C., 1997, Combining aquifer
testing using wells and spring studies to characterize the carbonate aquifer
at Mill Hole, Kentucky, Geological Society of America, Abstracts with Programs,
v. 29, No. 6, p. 183. |
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