2023-04-19_PERMIT FILE - C1981010 ‎(97)‎

• Permit No: C1981010
• IBM Index Class Name: Permit File
• Doc Date: 4/19/2023
• Doc Name: pages 4-1 to 4-100
• Section_Exhibit Name: 4.0 Protection of the Environmental & Public Resources
• Media Type: D
• Archive: No

• Leachate Characteristics and Overburden Attenuation
In the unlikely event that infiltrating water would produce a leachate, utility
wastes placed in the mine may release several elements in concentrations greater
than would otherwise occur.
Of the 22 chemical parameters selected for analysis in this study, 8 have been
selected for presentation in this section (refer to Table 4.3-12). These eight
chemical parameters have concentrations which exceeded the limits of the EPA's
Primary and Proposed Secondary Drinking Water Standards as set forth in Table
4.3-13. These limits will be referred to as the water quality criteria. The
parameters are barium, aluminum, boron, chromium, molybdenum, sulfate, vanadium,
and manganese.
Methods Used
The characteristics of the wastes under flow conditions, in general, and of the
pollutant mobility through the waste body in particular, were evaluated using
column leaching studies. Well designed column leaching tests are believed to
represent (on a Laboratory scale) the principal mechanism for any potential pol-
lutant migration for the disposal systems under consideration at the Trapper
Mine. It is anticipated that the results of column leaching studies should pro-
vide data on pollutant release from the waste and their attenuation and removal
in the overburden and, consequently, provide enough information to assess envi-
ronmental impacts of various waste disposal options at the Trapper Mine if perco-
lation should occur.
The medium used in the column studies should be selected from the class of likely
waste material and disposal site substrata. In addition, the column arrangement
should represent as broad a range of waste disposal placement options as practi-
cal. In order to evaluate the chemical interactions between ash, and ash and
4-55
All of
the chemical species that may leach from
the ash or ash -gypsum mixture,
with the exception of
sulfate, can be reduced in
concentration to drinking water
quality
by attenuation
in the overburden.
Methods Used
The characteristics of the wastes under flow conditions, in general, and of the
pollutant mobility through the waste body in particular, were evaluated using
column leaching studies. Well designed column leaching tests are believed to
represent (on a Laboratory scale) the principal mechanism for any potential pol-
lutant migration for the disposal systems under consideration at the Trapper
Mine. It is anticipated that the results of column leaching studies should pro-
vide data on pollutant release from the waste and their attenuation and removal
in the overburden and, consequently, provide enough information to assess envi-
ronmental impacts of various waste disposal options at the Trapper Mine if perco-
lation should occur.
The medium used in the column studies should be selected from the class of likely
waste material and disposal site substrata. In addition, the column arrangement
should represent as broad a range of waste disposal placement options as practi-
cal. In order to evaluate the chemical interactions between ash, and ash and
4-55