Mr. Kehrman received a M.S. in Geology with a Geophysics option, University of Missouri, 1968 and a B.S. in Geology with a Geophysics option, University of Missouri, 1967.

ROBERT KEHRMAN has been the regulatory advisor to WIPP since 1994 and was the primary preparer of the Permit Application and the DOE's Comments. He stated that the hazardous waste at WIPP was mostly hazardous metals and solvents. Most of this waste will be coming from more than 20 generator sites. WIPP itself will generate both derived (mixed) waste which will be buried in the repository and purely hazardous waste which will be shipped off-site.

The WIPP facility is sited in an isolated area where the main activities are grazing, mining for potash, and oil and gas exploration. No drilling or mining will be allowed within the site boundary. Mr. Kehrman stated that the SALADO formation was an impermeable, stable salt formation, which was isolated from groundwater by impermeable formations above and below the Salado. Although there is a small amount of water (or brine) trapped in the salt, in the undisturbed case water does not move in the salt. Mining has caused a disturbed rock zone to extend out about six feet from the excavations, and water from those fractures is drawn into the repository. Cracks across anhydrite and clay seams in the salt can allow water from areas beyond 6 feet to also enter the repository. Below the Salado is the CASTILE FORMATION. Above the Salado is the RUSTLER FORMATION which includes 2 water-bearing zones, the CULEBRA and the MAGENTA. The Culebra is the first regionally transmissive region above the site and the flowpath of greatest significance, but it is separated from the Salado. The DEWEY LAKE REDBEDS FORMATION is above the Rustler and has no water directly over the WIPP site. THE SANTA ROSA FORMATION is above the Dewey Lake Formation. Brine has been found over the WIPP site recharged from ponds built at the site for fire control.

The surface facilities were described, including the WASTE HANDLING BUILDING (WHB) and the 4 shafts into the underground. Then the underground Panels or Hazardous Waste Disposal Units (HWDUs) were described. To date only the 7 rooms of Panel 1 have been mined. The main strategy to prevent contamination at WIPP is never to open any waste containers at the facility. The ventilation system underground is very important, and air can be channeled through filters if there is any release. Flow can also be reversed in case of underground fire. Air is the most viable release pathway and the only way hazardous materials could leave the facility. Volatile Organic Compounds (VOCs) are continuously released from the waste. The VOCs are monitored in the underground. Room limits have been established for the amount of VOCs that may be released into the environment.

Closure activities: As each Panel is filled it will be closed with PANEL CLOSURES. These panel closures will include an explosion isolation wall and a concrete barrier. This barrier will be built into the panel tunnels to the interbeds above and below the excavation. When the facility is closed, shaft seals will return the shafts to permeability almost like the original state. Shafts will have some materials to render them impermeable immediately and then natural materials for long-term sealing. Groundwater monitoring around WIPP will start with the Disposal Phase and will continue for 30 years after Closure.


Lead-contaminated water has been leaking down the exhaust shaft. This is mainly from precipitation from the ventilation system, though there is a small leak in the Dewey Lake Redbeds/Santa Rosa horizon from ponding on the surface. This water is considered hazardous waste and is shipped offsite for disposal.

DOE does not want the requirement for Magnesium Oxide backfill totally removed from the Permit (although their written Comments deleted this requirement) but only want more flexibility on the amount used, size of containers, etc.

The purpose of WIPP is to be a Hazardous Waste Disposal Facility (among other things).

Brine that may exist under the repository in the Castile Formation is not a problem for WIPP because there are not any pathways between the two locations.

Panel Closures are not seals because VOCs will continue to seep out of the closed panels. However, particulate waste will not come out. Closures will employ commonly used materials, but the design and materials have never been used under these exact conditions before. Some shaftsealing design materials, like compacted salt, have never been used for sealing shafts before.

Financial assurance: Proper closure is dependent on proper funding.

The first waste stream to go to WIPP, Panel 1 would be non- mixed waste from Los Alamos National Laboratory (LANL). This waste would come before the Permit was issued. The DOE did not consider the impact of this waste on the Permit Application when they made the decision to ship it.

The only possible transport mechanism into the Culebra is up the shafts. There are no monitoring wells planned for the Magenta because the Culebra is so much more transmissive. There is also no evidence of KARST within the WIPP site boundaries, and within the site all 5 members of the Rustler Formation are discrete. The possibility of karst at the site was thoroughly investigated by drilling 3 or 4 test wells into "anomalies." Only borehole WIPP-33 to the west of the site showed caverns and evidence of karst. Other agencies, including regulatory agencies, have reviewed the data and agreed that there is no karstic flow at the site. Groundwater mostly infiltrates into the surface and evapotranspires back into the atmosphere. There is no connection between WIPP and flow in Nash Draw, and water in the Culebra is not from rainwater recharge but is about 12,000 years old.

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