March 26, 2001

RE: Response to Comments, Class 2 Modification Request
WIPP Hazardous Waste Facility Permit
EPA I.D. Number NM4890139088

Dear Concerned Citizen:

The New Mexico Environment Department (NMED) has denied the Class 2 permit modification request to the WIPP Hazardous Waste Facility Permit as submitted to the Hazardous Waste Bureau (HWB) in the following documents:

  • Request for Class 2 Permit Modifications, Dated 12/7/00, Rec'd 12/7/00
  • This modification was processed by NMED in accordance with the requirements specified in the New Mexico Hazardous Waste Regulations, NMAC (incorporating 40 CFR §270.42(b)).

    In their request, the Permittees proposed to modify the permit requirements for Drum Age Criteria (DAC). The DAC determines how long a container of waste must wait after packaging and venting before the generator site can obtain a gas sample from the headspace (void space) in the waste container. This is done in order to measure concentrations of hazardous volatile organic compounds (VOCs) in the container headspace. The proposed modification added numerous DAC values for specific waste packaging configurations (i.e., how many inner bags and liners were used in packaging the waste) for three different headspace gas sampling scenarios. The modification request replaced simple criteria (one time period for debris waste, another one for homogeneous waste) with a complex scheme of scenarios and lookup tables as a function of waste type, container type, packaging configuration, liner lid hole size, and vent filter characteristics.

    NMED's regulations provide several reasons for denying a Class 2 permit modification request, such as the modification request is incomplete; it does not comply with applicable requirements; or it fails to protect human health and the environment. Numerous public commentors identified significant technical inadequacies in the modification request. One such inadequacy was the complete failure of the Permittees to address how sites would obtain the required information necessary to determine appropriate DACs, including but not limited to modifications to visual examination, radiography, and acceptable knowledge permit requirements.

    NMED was unable to approve the modification "with changes" as allowed under the regulations because none of the commentors proposed sufficiently detailed changes to rectify the technical inadequacies they identified. Such changes would have had to be fairly substantial to overcome the significant shortcomings of the proposed modification, and would also have to be subject to additional public comment. Furthermore, NMED was unable to reclassify this modification request to follow the procedures for Class 3 modifications because the request was not approvable as submitted.

    This Class 2 modification was subject to a sixty (60) day public comment period, which ran from December 11, 2000 through February 9, 2001. NMED received written comments from ten individuals and organizations during this time.

    Further information on this administrative action may be found on the NMED WIPP Information Page on the World Wide Web at </wipp/>.

    If you have any questions regarding this matter, please contact Steve Zappe at (505) 827-1560, x1013.


    John E. Kieling, Manager
    Permits Management Program
    Hazardous Waste Bureau

    cc: James Bearzi, HWB
    Steve Zappe, HWB
    Inés Triay, DOE/CBFO
    Hank Herrera, Westinghouse