2008-10-30_HYDROLOGY - C1982056 ‎(3)‎

• Permit No: C1982056
• IBM Index Class Name: HYDROLOGY
• Doc Date: 10/30/2008
• Doc Name: 3rd Quarter 2008 DMRS ‎(COG-850000 & COG-850048)‎)‎
• From: Twentymile Coal Company
• To: WQCD
• Permit Index Doc Type: DMR’s
• Email Name: JHB
• Media Type: D
• Archive: No

Aqua-Tox, Inc.
4880 Robb Street, Suite 8
Wheat Ridge, CO 80033
[phone] aqua-toxocorn
ACUTE TOXICITY REPORT
Ceriodaphnia dubia
CLIENT NAME: Twentymile Coal Company SAMPLE I.D.: 092408-1
50 % MORTALITY TEST: FAIL TEST RESULT LC50: 55.825%
% SURVIVAL IN 100% DILUTION: 0%
SAMPLE DATE: 9-23-08 TIME: 17:05PM CLIENT ID: Site 10 RT
ORGANISM: Ceriodaphnia dubia AGE: < 24 hours old
TEST START: 9-24-08 12:10PM TEST FINISH: 9-26-08 12:10PM
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.: 7.00 mg/L
HARDNESS: 90.5 mg/L CHLORINE: ND
ALKALINITY: 54.02 mg/L TEMPERATURE: 20.0 deg C
pH: 7.95
SURVIVAL DATA DILUTIONS (%)
DATE (HOURS)CONTROL 6.25 12.5 25 50 75 100
9/24/2008 INITIAL 20 20 20 20 20 20 20
9/25/2008 24 20 20 20 20 18 10 1
9/26/2008 48 20 20 20 20 16 1 0
MORTALITY: 0 0 0 0 4 19 20
% SURVIVAL: 100% 100% 100% 100% 80% 5%
DAILY CHEMISTRY - (MIN/MAX) DILUTIONS (%)
0 6.25 12.5 25 50 75 100
CONDUCTIVITY (micros) 331/337 890/899 1411/1422 2420/2450 4340/4370 6090/7000 7760/7790
D.O. (mg/L) 7.0/7.4 7.0/7.4 7.0/7.4 7.0/7.4 7.0/7.3 6.9/7.3 6.8/7.3
pH 8.0/8,1 7.8/7.9 7.8/7.8 7.7/7.7 7.6/7.6 7.5/7.6 7.5/7.5
TEMPERATURE (deg C) 19.8/20.0 19.8/20.0 19.8/20.0 19.8/20.0 19.8/20.0 19.8/20.0 19.8/20.0
GENERAL CHEMISTRY - SAMPLE
AMMONIA: .62 mg/L D.O.: 6.83 mg/L
HARDNESS: 282.80 mg/L CHLORINE: ND
ALKALINITY: 1,254.53 mg/L TEMPERATURE: 20.0 dec C
pH: 7.46 D.O AFTER AERATION: NA
ANOEC CALCULATION METHQD METHOp; REFERENCE
50% SPEARMAN-KARBER EPA -821-R-02-012 October 2002 pg.78
ADDITIONAL COMMENTS:
Analysis
Conducted by: /,q-3io.ox Reviewed by:
Date: Date: y6 a
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