TESTIMONY OF DR. LOKESH CHATURVEDI; March 2, 1999.
Dr. Chaturvedi received a Ph.D. in Geological Science,
Cornell University, 1969 and a M.S. in Civil Engineering,
Purdue University, 1965. Dr. Chaturvedi is currently the
Deputy Director of EEG.
STABILITY OF UNDERGROUND HAZARDOUS WASTE DISPOSAL UNITS
(HWDUs): EEG's concerns about the stability of underground
waste rooms are limited to Panel 1, which was excavated
between 1986 and 1988. EEG has recommended abandoning Panel
1 and using a freshly excavated Panel 2 first as being the
safest way to proceed. If Panel 1 is used, the Permit
should require room stability evaluations to be performed in
each room of Panel 1 before starting waste emplacement and
an annual evaluation of the entire underground excavation.
The projected safe-life of a room must be sufficient to fill
the room and seal it IN THE ABSENCE OF MAINTENANCE. During
waste emplacement, maintenance of the roof support systems
will not be possible.
The DOE has said it would take 3 years to mine Panel 2.
Each Panel contains 7 rooms. The 4 Site and Preliminary
Design Validation (SPDV) rooms, which are the same size as
the Panel 1 rooms, were excavated in 6 weeks. Four rooms of
Panel 1 were excavated in 1 month. Therefore, 7 rooms in a
new Panel could be excavated in 2 months.
If NMED does not regulate room stability, the WIPP
project will be essentially self-regulated by the DOE. The
WIPP Land Withdrawal Act (LWA) prescribed annual evaluations
by the U.S. Bureau of Mines (USBM) in addition to quarterly
inspections by the Mine Safety and Health Administration
(MSHA). Congress dissolved the MSHA in 1995. After 1995
the DOE did not arrange to have annual USBM-style
independent evaluations of mine stability. Although MSHA
does oversee mine safety issues, their inspections focus on
occupational safety issues rather than the evaluation of the
structural integrity of the excavations.
Four SPDV rooms were excavated in the north experimental
area of WIPP in the spring of 1983. These rooms showed
rates of closure from salt creep 3 times higher than
expected and showed extensive fracturing in the roof, walls,
and floors. In May of 1989, after holes were drilled in the
ceiling of SPDV Room 1 to install rock bolts, extensive roof
fracturing was discovered throughout the SPDV Rooms.
Thereafter, access was restricted to these rooms. A 700-ton
pyramidal slab fell to the floor of SPDV Room 1 in February
of 1991. A similar roof-fall occurred in SPDV Room 2 in
June of 1994. Other roof-falls occurred in other
experimental heated rooms in 1990-91. One room had been
entered by personnel only 18 days before a roof-fall.
In 1991 an expert panel concluded that, without roof
support, Panel 1 rooms would only last between 2 and 6 years
and would need modifications and maintenance to last until
1998. By 1990 most areas in the underground had been
systematically rock-bolted. In 1991 a secondary support
system was installed in Room 1, Panel 1. Later secondary
support systems were installed in other rooms and drifts of
Panel 1. Room 7 would be the first room to receive waste.
It was pattern-bolted in 1988, re-bolted in 1994, and
received a third support system in May of 1998. Regular
maintenance is required to replace failed bolts. Also, each
bolt in Room 1, Panel 1 has to be manually de-tensioned.
[The Room 1 roof has separated from the rock above it and is
slowly being lowered by the "unscrewing" of the rock bolts.]
With normal maintenance and without remediation, a rough
estimate of a 1 to 5 year safe-life is projected for all
areas in Panel 1. Salt creep is pushing the rock layers of
the roof sideways against the anchored rock bolts and
breaking them. The rate of bolt failure increases with
The DOE's plan to start mining Panel 2 within 1 year
after beginning to fill Panel 1 may increase stresses on
Panel 1 rooms. The DOE's goal to fill Panel 1 in 4 years is
unrealistic in the initial years. [The DOE has 15 TRUPACT-
IIs in service at this time. New TRUPACT-IIs will have to
be manufactured in order for the DOE to meet its goal of
filling Panel 1 in 4 years.] Rock bolts in a roof-fall may
pierce a large number of drums. This could increase the
amount of released solid hazardous and radioactive waste
material. The DOE's analysis argues that a roof-fall would
not result in any breached drums, but there is no evidence
that WIPP drums are that robust. The DOE's analysis assumes
bags of MgO backfill will cushion the drums in a roof-fall.
If MgO backfill is not required in the Permit, roof-fall
scenarios should be reanalyzed.
GROUNDWATER DETECTION MONITORING IN THE DEWEY LAKE
The DOE's Permit Application and their written Comment No.
273 incorrectly states that the Dewey Lake Redbeds Formation
and the Santa Rosa Formation contain little or no water near
the WIPP facility and the shafts. The DOE's 1997
investigations in those areas showed better quality
groundwater in the Lower Santa Rosa/Upper Dewey Lake Redbeds
Formations than in any other water-bearing zone at the WIPP
site. EEG recommends that in addition to the 7 monitoring
wells required in the draft Permit, another monitoring well
be drilled in the Lower Santa Rosa/Upper Dewey Lake Redbeds
Formations near the WIPP exhaust shaft. EEG also recommends
that the DOE be required to provide an accurate description
of the hydrology of these formations.
The 1997 investigations were conducted to identify the
source of water leakage in the exhaust shaft. [Each year,
more than 14,000 gallons of lead-contaminated water
collected at the bottom of the exhaust shaft are shipped off-
site as hazardous waste.] A water-saturated horizon was
found in the Lower Santa Rosa/Upper Dewey Lake Redbeds
Formations at the same depth range where water has been
found leaking into the exhaust shaft (50 to 80 feet below
the ground surface). In 1985, moisture was observed during
inspections of the shaft liner. When the exhaust fans were
on, the moisture evaporated before reaching the underground
facility. A few years after 1988, increasing moisture was
adversely affecting air-sampling probes in the shaft. Video
inspection of the shaft in 1995 showed a stream of water
leaking into the shaft [inflow]. The DOE has stated that
most of the exhaust shaft water is the result of
precipitation or condensation from the ventilation system.
However, the DOE's 1996 investigation showed that this is
unlikely. For the evaluation period, precipitation of water
in the shaft was consistently negative (meaning the dry air
evaporates water from the shaft rather than precipitating
Dr. Chaturvedi presented footage of a 1998 videotaped DOE
inspection of the exhaust shaft. Inflow was at the same
depth as the 1995 video inspection. This suggests that
despite evaporation, inflow has continued for at least 4 to
5 years. The DOE objected to their videotape being placed
into evidence, claiming that only a Registered Professional
Engineer could accurately interpret the videotape. Dr.
Chaturvedi was allowed to show the videotape as a
demonstration and was not allowed to narrate it. The
videotape showed water flowing down the shaft wall and
droplets of water being pushed upward by the exhaust
airflow. The DOE claimed the videotape had been recorded
under conditions of reduced ventilation.
HIGHLIGHTS OF CROSS-EXAMINATION OF DR. LOKESH
Dr. Chaturvedi has great respect for the Ground Control
staff at WIPP and believes they are competent. However,
geotechnical mechanical information may or may not provide
warning of instability. The DOE queried Dr. Chaturvedi on
some of the statements and conclusions of the members of the
1991 expert panel examining the roof-fall. One of the 11
experts said that a 20-year life was feasible for Panel 1
with good support and repair. EEG-63, "Stability Evaluation
of the Panel 1 Rooms and the E140 Drift at WIPP," stated
that the Panel 1 rooms could be safely kept open without
maintenance for 1 to 2 years after installation of a new
roof support system. But if maintenance had to be performed
during this period, it could not be done if there was waste
in the rooms. Also, the newest support system in Room 7 is
10 months old already, and there may not be sufficient
installation space in that room. Rooms are filled from back
to front, and filled rooms are not as easy to inspect (even
visually) as unfilled rooms. Roof bolts help support the
roof beam but will not stop the convergence. Salt creep
continues to push the roof sideways from the pillars on each
side of the rooms. Room life could be extended
indefinitely, but this would be costly and would require
ongoing maintenance. Prohibiting use of Panel 1 in the
Permit is the best thing to do. Even the DOE anticipates
only using part of Panel 1.
The DOE stated that the SPDV Room 1 roof was unsupported
and was allowed to fall. Dr. Chaturvedi said that no
experiments were designed to test a roof-fall. The DOE
stated that all Panel 1 rooms had at least 3 remotely read
extensometers, that Room 1 is equipped with load cells, and
that there would be some period of warning from visual
inspection and remote instruments before a roof-fall. But
personnel entered one experimental room 18 days before a
roof-fall occurred in 1990. None of the WIPP Mining Safety
and Health Administration (MSHA) reports Dr. Chaturvedi has
seen have ever addressed mine structural integrity. There
are no regulators performing United States Bureau of Mines
(USBM) inspections at WIPP. One safety option would be to
remove about 7 feet of unstable rock above each room.
However, this would change accident scenarios because--
although unlikely--if rock did fall, it would fall 7 feet
more than in the original scenarios. Rooms might also be
better designed if they were narrower, but then equipment
and 7-packs might not fit. Newly excavated rooms (33 feet
wide) could safely last 5 years.
Shafts at the Santa Rosa/Dewey Lake Redbeds horizon were
dry and unlined when first mapped by Powers and Holt in the
mid-1980s. Water would have shown up during mapping only if
sufficient time had elapsed between excavation and mapping.
Measurable seepage of concern was discovered in 1995 when it
affected the monitoring probe in the exhaust shaft. It is
unknown how long water had been seeping into the shaft
because the shaft was not inspected before 1995.
The Culebra is not the first regionally extensive water-
bearing layer above the repository. The first is the
Rustler/Salado interface. In some boreholes, permeability
is higher for the Rustler/Salado than the Culebra. Also,
the Dewey Lake Redbeds Formation has much better water
quality than the Culebra.
The videotape probe was lowered from a spot more than 30
feet above the ground surface, and that amount has to be
subtracted from the "50 to100" feet below ground surface
described as the area of water seepage in the shaft. The
1997 reports agreed that the depth of water found by
drilling in the Santa Rosa/Dewey Lake Redbeds Formations was
the same as the exhaust shaft flow. The exhaust shaft sump
once accumulated almost 2,000 gallons of water in about a
week (though the amount varies).
FLOW PATHWAYS IN THE SALADO: In 1995 water had moved all
the way down the exhaust shaft below the repository floor to
Marker Bed 139 (MB139)--a permeable zone under the
repository--and had moved along this marker bed for several
hundred feet. These interbeds and marker beds are
continuous layers that run across the entire Delaware Basin
for tens of miles--sometimes for hundreds of miles. Salt
will not completely seal off the waste. There are pathways
for fluid movement. The Delaware Basin has about 43 marker
beds and other thinner beds of anhydrite, clay, and other
rock. [Anhydrite is a white to grayish or reddish mineral
of anhydrous calcium sulfate, CaSO4.] Salt is plastic, but-
-because of the layers--the salt formation is divided.
The hydraulic conductivity of each of the marker beds and
interbeds is different from the halite. [Halite is rock
salt.] The conductivity of MB139 is about a million times
higher than the salt. MB139 is an undulating layer up to 5
feet thick 3 to 5 feet below the floor of the repository and
is modeled as a zone through which water and gas may leak
laterally from the repository. Flow pathways from the
repository are not controlled by salt but instead by salt
mixed with clay, clay layers, and fractured anhydrite
layers. MB138 is about 20 feet above the roofs of the waste
rooms. MB138 and MB139 are fractured anhydrite and clay.
Anhydrite is more conductive than salt, and fracturing makes
it more conductive still. Fractures can remain open in
anhydrite, and there can be openings where the anhydrite
interfaces with the salt.
EEG has said inflow in the shaft from the Dewey Lake
Redbeds Formation can be traced to recharge. The DOE has
said that the recharge comes from ponds created on the
surface for fire control. More information is needed on
this subject, but if the Dewey Lake Redbeds Formation is
saturated for more than 80 acres, as indicated in the 1997
reports, recent recharge from the ponds is probably not the
source. The Santa Rosa Formation is extensive east of the
site but pinches out at the center of the site, to the west.
Flow in the Santa Rosa and Dewey Lake Redbeds Formations is
generally south, but specific data on its course is limited.
Only part of the WIPP site is characterized with respect to
this water-bearing zone, and there is not enough data
available to accurately model the Santa Rosa and Dewey Lake
Redbeds Formations as a potential pathway. Because of the
lack of data, it cannot be unequivocally stated that the
Culebra is the most transmissive unit above the site.
Definition of the water table at WIPP has long been a
major question. Leonard Konikow of the United States
Geological Survey (USGS) has said that if you do not know
the water table, you do not know the hydrology of the site.
Based on the limited available data, the DOE defined the
water table as being in the Dewey Lake Redbeds Formation.
However, there is no data in the Permit Application on this
formation. The Magenta and Culebra dolomites are saturated
in every test well on the WIPP site, and all members of the
Rustler are water bearing at some locations. [Dolomites are
deposits of a light-tinted mineral (CaMg(CO3)2), either
gray, white, or pink.]
The surface of the WIPP site is covered by sand, and
there are no well-developed surface drainage patterns at
WIPP. The sands are transmissive to rainwater. Directly
beneath the sands is the MESCALERO CALICHE FORMATION, which
is generally continuous but does have gaps. It is possible
for rainwater to penetrate the caliche through these gaps to
reach the lower strata. Dr. Chaturvedi did not know whether
the Magenta and the Culebra are connected in nearby wells.
In areas where there are wells in the Culebra but not in the
Magenta, it is uncertain whether the two are connected.
USGS and Sandia National Laboratory investigations state
that recharge for the Rustler and Dewey Lake Redbeds is
north, northwest of WIPP. WIPP-33 (a well) is drilled in a
sinkhole. WIPP-14 (also a well) is also drilled in a closed
topographic depression, but Dr. Chaturvedi has not seen
evidence of it being a sinkhole.
As the floor of the repository buckles and shifts from
salt creep, small fractures could be created over time, but
these fractures probably would not go down 700 to 800 feet
vertically to possible brine pockets at the Salado/Castile
interface. The most likely path for releases of hazardous
materials from the repository is through fractured
interbeds. If a roof-fall connects the waste rooms to
Anhydrite Layers A or B (7 to 13 feet above the repository),
the anhydrite layers could become pathways. Then a borehole
could allow contamination to travel higher. The marker beds
connect the repository with the shafts and all the other
boreholes in the basin that cross them.
Permeability increases in any disturbed area but
decreases very quickly as you move away from an excavation.
The only way to increase the permeability away from the
excavations is with water or gas. Although the Culebra is
probably the most prolific water-bearing zone, the Magenta,
Dewey Lake Redbeds, and the Rustler/Salado contact are other
Dr. Chaturvedi does not believe that any waste has ever
been brought to WIPP. Bill Bartlett, also of EEG, checked
out rumors of nuclear waste in the repository with radiation
detection equipment and found nothing.