2011-02-02_HYDROLOGY - C1982056 ‎(5)‎

• Permit No: C1982056
• IBM Index Class Name: HYDROLOGY
• Doc Date: 2/2/2011
• Doc Name: 4th Quarter 2010 DMRS ‎(CO-0036684)‎
• From: Twentymile Coal Company
• To: DRMS
• Permit Index Doc Type: DMR’s
• Email Name: JDM
• Media Type: D
• Archive: No

Aqua-Tox, Inc.
} 4880 Robb Street, Suite 8
Wheat Ridge, CO 80033
[phone] aqua-tox.com
` ACUTE TOXICITY REPORT
Ceriodaphnia dubia
CLIENT NAME: 20-Mile Coal Company SAMPLE I.D.: 111610-2
50 % MORTALITY TEST: Pass TEST RESULT LC50: >100%
% SURVIVAL IN 100% DILUTION: 60%
SAMPLE DATE: 11-15-10 TIME: 16:15P CLIENT ID: Site 62
ORGANISM: Ceriodaphnia dubia AGE: .< 24 ho urs old
TEST START: 11-16-10 13:50P TEST FINISH: 11-18-10 13:50P
TYPE OF TEST:_LC50, 48 hours, static, renewal, moderately hard fresh synthetic dilution water.

MODERATELY HARD FRESH SYNTHETIC DILUTION WATER CONSTITUENT
AMMONIA: ND D.O.: 6.94 mg/L
HARDNESS: 98.91 mg/L CHLORINE: ND
ALKALINITY: 58.26 mg/L TEMPERATURE: 19.5 deg C
pH: 8.04
SURVIVAL DATA DILUTIONS (%)
DATE (HOURS)CONTROL 6.25 12.5 25 50 75 100
11/16/2010 INITIAL 20 20 20 20 20 20 20
11/17/2010 24 20 20 20 20 19 19 16
11/18/2010 48 20 20 20 20 19 16 12
MORTALITY: 0 0 0 0 1 4 8
% SURVIVAL: 100% 100% 100% 100% 95% 80% 60%
DAILY CHEMISTRY - (MIN/MAX) DILUTIONS (%)
0 6.25 12.5 25 50 75 100
CONDUCTIVITY (micros) 323/339 945/964 1578/1594 2030/2060 2470/2500 3310/3340 4280/4310
D.O. (mg/L) 6.9/7.3 6.9/7.3 7.0/7.4 7.1/7.4 7.2/7.4 7.3/7.4 7.4/7.4
pH 8.0/8.3 8.0/8.3 7.9/8.3 7.9/8.4 7.8/8.5 7.7/8.6 7.6/8.7
TEMPERATURE (deg C) 19.5/20.1 19.5/20.1 19.5/20.1 19.5/20.1 19.5/20.1 19.5/20.1 19.5/20.1
GENERAL CHEMISTRY - SAMPLE
AMMONIA: 0.05 mg/L D.O.: 7.62 mg/L
HARDNESS: 2,438.45 mg/L CHLORINE: ND
ALKALINITY: 515.00 mg /L TEMPERATURE: 19.5 deg C
pH: 7.87 - D.O AFTER AERATION: NA
ANOEC CALCULATION METHOD METHOD REFERENCE
50% SPEARMAN-KARBER EPA -821-R-02-012 October 2002 pg.78
ADDITIONAL COMMENTS:
Analysis
Conducted by. Reviewed by:
Date: t- 2l - 10 Date. - , ,o