1997-04-24_REVISION - M1977493 ‎(14)‎

• Permit No: M1977493
• IBM Index Class Name: REVISION
• Doc Date: 4/24/1997
• Doc Name: EPAS- Appendix C- Leachate Test
• From: Climax Molybdenum
• To: DMG
• Type & Sequence: SR2
• Email Name: ACS
• Media Type: D
• Archive: No

Environmental
• LEACHATE TEST FOR TAILINGS/SOILS IN EAGLE PARK RESERVOIR
The Meteoric Water Mobility Procedure of the Nevada Division of Environmental Protection
(1990)will be used as a basis for the leachate test. The test will consist of
1. Collect representative sample of material; 5 kilograms of sample with particle size less than
5 centimeters are required.
2. Place the sample in an extraction device that allows continuous wetting of the sample by
circulation of the lixiviant.
3. Add a volume of lixiviant equal in weight to the weight of the sample plus additional volume
necessary to saturate the sample. The lixiviant is defined below.
4. Circulate, agitate, or mix the sample and lixiviant for 24 hours.
5. One hour after circulation ends,decant the lixiviant and prepare for analysis by acidifying.
6. Analyze for the following parameters: total recoverable arsenic, iron,manganese, selenium,
and mercury and dissolved cadmium,chromium(Cr III and Cr VI),copper, iron, lead,
manganese, nickel, silver, and zinc.
The following information should be recorded:
• 0 The procedure used to collect a representative sample;
• The adjusted pH of the original lixiviant;
• The final pH of fluid after mixing;
• Percentage of sample passing 200 mesh;
0 Total weight of solid sample;
• Moisture required to saturate sample;
• Time of contact in extraction device;
Synopsis of the technique and equipment used to leach the sample(i.e.,column, batch,etc.).;
and
• Results of the analysis of the lixiviant after ending the extraction.
x'viant
The Meteoric Water Mobility Procedure specifies a lixiviant of laboratory grade water with pH
adjusted to between 5.5 and 6.0 with reagent grade nitric acid. For this test the lixiviant will be
laboratory grade water with pH adjusted to between 7.5 and 8.0 with reagent grade sodium
hydroxide. The reason for testing at the higher pH is that the pH in Eagle Park Reservoir is
expected to be similar to that in Chalk Mountain Reservoir. Four pH measurements were taken
of water from the bottom of Chalk Mountain Reservoir between June, 1993 and February, 1994.
The field pH values ranged from 7.66 to 8.62 and laboratory pH values ranged from 7.28 to 8.31.
Therefore the lixiviant should be slightly alkaline.
• Reference
Nevada Division of Environmental Protection,Bureau of Mining Regulation and Reclamation,
1990, Meteoric Water Mobility Procedure, September 19, 1990.
leach.doc [6/7/96] CO2103