TABLE SO /Air Cyanide Detoxification Test D5 AMMTEC FS... · Sample: WH4270 Operating Conditions ... Soln (S.G.) 0.999 CNp determined by Picric Acid method (CNp is equivalent to CN

TABLE SO2/Air Cyanide Detoxification Test D5Sample: WH4270

Operating Conditions Client: Vista Gold Corporation Date: 26 Oct 2011Project: Mt Todd Project Test: A13575 D5

Time pH KG Temp D.O Meta Cu Feed Lime CN load SO2 Ratio CuSO4.5H2O Ca(OH)2 Ret Time SolutionRatio

min mVoC ppm mL/hr mL/hr mL/hr mL/hr g/hr gSO2/gCN ppm gCa(OH)2/gSO2 min L/hr

0 9.60 -87 22 5.1 10.5 10.5 540 16.0 0.06 4.72 23 1.10 49.91 0.3415 9.52 -105 4.4 10.5 10.5 540 16.0 0.06 4.72 23 1.10 49.91 0.3430 9.48 -138 4.8 10.5 10.5 540 16.0 0.06 4.72 23 1.10 49.91 0.3445 9.70 -178 5.0 10.5 10.5 540 16.0 0.06 4.72 23 1.10 49.91 0.3460 9.53 -189 4.7 10.5 10.5 540 16.0 0.06 4.72 23 1.10 49.91 0.3475 9.67 -167 4.9 10.0 10.0 490 27.0 0.06 4.95 24 1.95 53.63 0.3190 9.54 -169 4.8 10.0 10.0 490 27.0 0.06 4.95 24 1.95 53.63 0.31105 9.49 -149 4.5 10.0 10.0 490 27.0 0.06 4.95 24 1.95 53.63 0.31120 9.50 -142 4.8 10.0 10.0 490 27.0 0.06 4.95 24 1.95 53.63 0.31135 9.56 -133 4.7 10.0 10.0 490 20.0 0.06 4.95 24 1.45 54.34 0.31150 9.81 -139 4.9 10.0 10.0 490 20.0 0.06 4.95 24 1.45 54.34 0.31165 9.59 -136 4.7 10.0 10.0 490 20.0 0.06 4.95 24 1.45 54.34 0.31180 9.60 -135 4.7 10.0 10.0 490 20.0 0.06 4.95 24 1.45 54.34 0.31AVG 9.58 -144 22.0 4.8 10.19 10.19 509 20.62 0.06 4.86 23 1.46 52.34 0.32

Reactor Size 480 COMMENTS: 2.83 2.83 5.72 88.63CuSO4.5H2O Conc (gpl) 0.73 Feed, Meta, Copper and Lime flowrates determined from hourly average.Meta Conc (gpl) 41.03 41.03g/L Na2S2O5Ca(OH)2 (gpl) 20.00 20g/L LimeAgitator (rpm) 1100Air Flow (L/min/L) MaxSolids (S.G.) 2.61 Estimated solids s.gSolids (% wt) 60.74Soln (S.G.) 0.999 CNp determined by Picric Acid method (CNp is equivalent to CN(wad))Slurry (S.G.) 1.598

Sample Time CNFREE CNp Cu Fe Ni Zn Calculated COMMENTSmin ppm ppm ppm ppm ppm ppm CN total

FEED 0 132.7 181.6 34.10 11.40 0.65 5.30 213.4DISP 1A 0-30 30 N/a 0.34 0.20 1.00 0.05 0.02 3.13DISP 1B 30-60 60 N/a 1.73 0.22 4.60 0.05 0.02 14.59DISP 2A 60-90 90 N/a 3.06 0.26 5.10 0.05 0.02 17.31DISP 2B 90-120 120 N/a 0.94 0.26 6.50 0.05 0.02 19.11DISP 3A 120-150 150 N/a 2.97 0.20 5.80 0.05 0.02 19.18DISP 3B 150-180 180 N/a 1.87 0.22 6.40 0.05 0.02 19.76

AVERAGE SOLN ASSAYS 1.82 0.23 4.90 0.05 0.02 15.51AVERAGE SOLN ASSAYS (LAST 2 SAMPLES) 2.42 0.21 6.10 0.05 0.02 19.47

0

0.5

1

1.5

2

2.5

3

3.5

30 60 90 120 150 180

CN(w

ad) (mg/L)

Time (min)

CN(wad) vs Time

0

0.05

0.1

0.15

0.2

0.25

0.3

0 0.5 1 1.5 2 2.5 3 3.5

[M] (m

g/L)

CN(wad) (mg/L)

[M] vs CN(wad)

Cu

Ni

Zn

Linear (Cu)

Linear (Ni)

Linear (Zn)


Operating Conditions Client: Vista Gold Corporation Date: 3 Nov 2011Project: Mt Todd Project Test: A13575 D6



0 8.53 -96 22 4.4 10.0 10.0 460 10.0 0.05 4.75 5 0.80 58.78 0.2915 8.64 -110 3.9 10.0 10.0 460 10.0 0.05 4.75 5 0.80 58.78 0.2930 8.72 -119 3.9 10.0 10.0 460 10.0 0.05 4.75 5 0.80 58.78 0.2945 8.49 -111 3.6 10.0 10.0 460 10.0 0.05 4.75 5 0.80 58.78 0.2960 8.50 -112 3.8 10.0 10.0 460 10.0 0.05 4.75 5 0.80 58.78 0.2975 8.61 -111 3.8 10.0 10.0 480 15.0 0.05 4.55 5 1.21 55.92 0.3090 8.56 -112 3.9 10.0 10.0 480 15.0 0.05 4.55 5 1.21 55.92 0.30105 8.51 -111 4.0 10.0 10.0 480 15.0 0.05 4.55 5 1.21 55.92 0.30120 8.48 -110 4.0 10.0 10.0 480 15.0 0.05 4.55 5 1.21 55.92 0.30135 8.61 -100 4.0 10.0 10.0 480 30.0 0.05 4.55 5 2.41 54.34 0.30150 8.52 -97 4.0 10.0 10.0 480 30.0 0.05 4.55 5 2.41 54.34 0.30165 8.45 -94 4.0 10.0 10.0 480 30.0 0.05 4.55 5 2.41 54.34 0.30180 8.59 -93 4.0 10.0 10.0 480 30.0 0.05 4.55 5 2.41 54.34 0.30AVG 8.55 -106 22.0 3.9 10.00 10.00 472 17.69 0.05 4.63 5 1.42 56.47 0.30





0

1

2

3

4

5

6

7

30 60 90 120 150 180

CN(w

ad) (mg/L)

Time (min)

CN(wad) vs Time

0

0.5

1

1.5

2

2.5

3

0 1 2 3 4 5 6 7

[M] (m

g/L)

CN(wad) (mg/L)

[M] vs CN(wad)

Cu

Ni

Zn

Linear (Cu)

Linear (Ni)

Linear (Zn)


Operating Conditions Client: Ausenco Date: 25 Oct 2011Project: Mt Todd Project Test: A13575 D7



0 8.52 -78 22 5.3 10.0 0.0 440 15.0 0.06 2.76 0 1.85 61.94 0.2715 8.49 -277 5.1 10.0 0.0 440 15.0 0.06 2.76 0 1.85 61.94 0.2730 8.52 -337 5.4 10.0 0.0 440 15.0 0.06 2.76 0 1.85 61.94 0.2745 8.61 -364 5.4 10.0 0.0 440 15.0 0.06 2.76 0 1.85 61.94 0.2760 8.56 -372 5.4 10.0 0.0 440 15.0 0.06 2.76 0 1.85 61.94 0.2775 8.50 -369 5.4 10.0 0.0 440 5.0 0.06 2.76 0 0.62 63.30 0.2790 8.49 -359 5.4 10.0 0.0 440 5.0 0.06 2.76 0 0.62 63.30 0.27105 8.54 -360 5.4 10.0 0.0 440 5.0 0.06 2.76 0 0.62 63.30 0.27120 8.53 -361 5.4 10.0 0.0 440 5.0 0.06 2.76 0 0.62 63.30 0.27135 8.54 -360 5.4 10.0 0.0 470 0.0 0.06 2.58 0 0.00 60.00 0.29150 8.54 -359 5.4 10.0 0.0 470 0.0 0.06 2.58 0 0.00 60.00 0.29165 8.53 -361 5.4 10.0 0.0 470 0.0 0.06 2.58 0 0.00 60.00 0.29180 8.58 -360 5.4 10.0 0.0 470 0.0 0.06 2.58 0 0.00 60.00 0.29AVG 8.53 -332 22.0 5.4 10.00 0.00 449 7.31 0.06 2.70 0 0.90 61.73 0.28





0

5

10

15

20

25

30

35

30 60 90 120 150 180

CN(w

ad) (mg/L)

Time (min)

CN(wad) vs Time

‐2

0

2

4

6

8

10

12

14

16

18

20

0 5 10 15 20 25 30 35

[M] (m

g/L)

CN(wad) (mg/L)

[M] vs CN(wad)

Cu

Ni

Zn

Linear (Cu)

Linear (Ni)

Linear (Zn)





0 8.53 -172 22 4.0 10.5 0.0 440 18.0 0.06 4.06 0 1.51 61.47 0.2715 8.50 -228 4.7 10.5 0.0 440 18.0 0.06 4.06 0 1.51 61.47 0.2730 8.48 -329 5.2 10.5 0.0 440 18.0 0.06 4.06 0 1.51 61.47 0.2745 8.54 -355 5.3 10.5 0.0 440 18.0 0.06 4.06 0 1.51 61.47 0.2760 8.48 -370 5.3 10.5 0.0 440 18.0 0.06 4.06 0 1.51 61.47 0.2775 8.51 -367 5.3 10.0 0.0 520 7.0 0.07 3.27 0 0.62 53.63 0.3290 8.47 -367 5.3 10.0 0.0 520 7.0 0.07 3.27 0 0.62 53.63 0.32105 8.55 -367 5.3 10.0 0.0 520 7.0 0.07 3.27 0 0.62 53.63 0.32120 8.48 -363 5.3 10.0 0.0 520 7.0 0.07 3.27 0 0.62 53.63 0.32135 8.52 -363 5.3 10.0 0.0 460 18.0 0.06 3.70 0 1.59 59.02 0.29150 8.47 -358 5.3 10.0 0.0 460 18.0 0.06 3.70 0 1.59 59.02 0.29165 8.50 -360 5.3 10.0 0.0 460 18.0 0.06 3.70 0 1.59 59.02 0.29180 8.54 -356 5.3 10.0 0.0 460 18.0 0.06 3.70 0 1.59 59.02 0.29AVG 8.51 -335 22.0 5.2 10.19 0.00 471 14.62 0.06 3.68 0 1.26 58.11 0.29





‐2

0

2

4

6

8

10

12

14

16

18

30 60 90 120 150 180

CN(w

ad) (mg/L)

Time (min)

CN(wad) vs Time

0

0.5

1

1.5

2

2.5

0 2 4 6 8 10 12 14 16 18

[M] (m

g/L)

CN(wad) (mg/L)

[M] vs CN(wad)

Cu

Ni

Zn

Linear (Cu)

Linear (Ni)

Linear (Zn)





0 8.54 -272 22 5.2 11.0 0.0 580 7.0 0.08 4.15 0 0.44 48.16 0.3615 8.50 -356 5.3 11.0 0.0 580 7.0 0.08 4.15 0 0.44 48.16 0.3630 8.47 -368 5.3 11.0 0.0 580 7.0 0.08 4.15 0 0.44 48.16 0.3645 8.55 -363 5.2 11.0 0.0 580 7.0 0.08 4.15 0 0.44 48.16 0.3660 8.49 -355 5.1 11.0 0.0 580 7.0 0.08 4.15 0 0.44 48.16 0.3675 8.59 -358 5.2 10.0 0.0 520 3.0 0.07 4.20 0 0.21 54.03 0.3290 8.50 -356 5.2 10.0 0.0 520 3.0 0.07 4.20 0 0.21 54.03 0.32105 8.98 -370 5.3 10.0 0.0 520 3.0 0.07 4.20 0 0.21 54.03 0.32120 9.09 -359 5.2 10.0 0.0 520 3.0 0.07 4.20 0 0.21 54.03 0.32135 8.91 -353 5.2 10.0 0.0 470 0.0 0.06 4.65 0 0.00 60.00 0.29150 9.59 -352 5.1 10.0 0.0 470 0.0 0.06 4.65 0 0.00 60.00 0.29165 9.54 -342 5.0 10.0 0.0 470 0.0 0.06 4.65 0 0.00 60.00 0.29180 9.45 -339 5.0 10.0 0.0 470 0.0 0.06 4.65 0 0.00 60.00 0.29AVG 8.86 -349 22.0 5.2 10.38 0.00 528 3.62 0.07 4.30 0 0.24 53.17 0.33





0

2

4

6

8

10

12

14

30 60 90 120 150 180

CN(w

ad) (mg/L)

Time (min)

CN(wad) vs Time

0

0.5

1

1.5

2

2.5

0 2 4 6 8 10 12 14

[M] (m

g/L)

CN(wad) (mg/L)

[M] vs CN(wad)

Cu

Ni

Zn

Linear (Cu)

Linear (Ni)

Linear (Zn)





0 8.53 -192 22 4.8 10.0 0.0 470 5.0 0.06 5.17 0 0.31 59.38 0.2915 8.59 -281 4.9 10.0 0.0 470 5.0 0.06 5.17 0 0.31 59.38 0.2930 8.48 -328 5.3 10.0 0.0 470 5.0 0.06 5.17 0 0.31 59.38 0.2945 8.51 -349 5.4 10.0 0.0 470 5.0 0.06 5.17 0 0.31 59.38 0.2960 8.47 -363 5.5 10.0 0.0 470 5.0 0.06 5.17 0 0.31 59.38 0.2975 8.50 -362 5.5 10.0 0.0 480 20.0 0.06 5.06 0 1.23 56.47 0.3090 8.47 -364 5.5 10.0 0.0 480 20.0 0.06 5.06 0 1.23 56.47 0.30105 8.51 -361 5.5 10.0 0.0 480 20.0 0.06 5.06 0 1.23 56.47 0.30120 8.45 -357 5.5 10.0 0.0 480 20.0 0.06 5.06 0 1.23 56.47 0.30135 8.45 -356 5.5 10.0 0.0 520 23.0 0.07 4.67 0 1.42 52.08 0.32150 8.49 -357 5.5 10.0 0.0 520 23.0 0.07 4.67 0 1.42 52.08 0.32165 8.46 -356 5.4 10.0 0.0 520 23.0 0.07 4.67 0 1.42 52.08 0.32180 8.47 -358 5.5 10.0 0.0 520 23.0 0.07 4.67 0 1.42 52.08 0.32AVG 8.49 -337 22.0 5.4 10.00 0.00 488 15.15 0.07 4.97 0 0.94 56.07 0.30





0

1

2

3

4

5

6

7

8

30 60 90 120 150 180

CN(w

ad) (mg/L)

Time (min)

CN(wad) vs Time

0

1

2

3

4

5

6

7

8

9

10

0 1 2 3 4 5 6 7 8

[M] (m

g/L)

CN(wad) (mg/L)

[M] vs CN(wad)

Cu

Ni

Zn

Linear (Cu)

Linear (Ni)

Linear (Zn)





0 8.48 -228 22 5.2 10.0 10.0 450 18.0 0.06 5.40 22 1.11 59.02 0.2815 8.46 -195 4.3 10.0 10.0 450 18.0 0.06 5.40 22 1.11 59.02 0.2830 8.50 -181 4.1 10.0 10.0 450 18.0 0.06 5.40 22 1.11 59.02 0.2845 8.50 -172 4.3 10.0 10.0 450 18.0 0.06 5.40 22 1.11 59.02 0.2860 8.46 -164 4.4 10.0 10.0 450 18.0 0.06 5.40 22 1.11 59.02 0.2875 8.47 -161 4.6 10.0 10.0 500 17.0 0.07 4.86 20 1.05 53.63 0.3190 8.47 -152 4.4 10.0 10.0 500 17.0 0.07 4.86 20 1.05 53.63 0.31105 8.46 -146 4.5 10.0 10.0 500 17.0 0.07 4.86 20 1.05 53.63 0.31120 8.47 -137 4.4 10.0 10.0 500 17.0 0.07 4.86 20 1.05 53.63 0.31135 8.48 -125 4.4 10.0 10.0 470 20.0 0.06 5.17 21 1.23 56.47 0.29150 8.51 -117 4.6 10.0 10.0 470 20.0 0.06 5.17 21 1.23 56.47 0.29165 8.46 -106 4.5 10.0 10.0 470 20.0 0.06 5.17 21 1.23 56.47 0.29180 8.48 -95 4.5 10.0 10.0 470 20.0 0.06 5.17 21 1.23 56.47 0.29AVG 8.48 -152 22.0 4.5 10.00 10.00 472 18.31 0.06 5.15 21 1.13 56.49 0.29





0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

30 60 90 120 150 180

CN(w

ad) (mg/L)

Time (min)

CN(wad) vs Time

0

0.5

1

1.5

2

2.5

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2

[M] (m

g/L)

CN(wad) (mg/L)

[M] vs CN(wad)

Cu

Ni

Zn

Linear (Cu)

Linear (Ni)

Linear (Zn)


Operating Conditions Client: Ausenco Date: 3 Nov 2011Project: Mt Todd Project Test: A13575 D12



0 8.46 -117 22 3.9 10.0 10.0 480 30.0 0.06 4.55 10 2.06 54.34 0.3015 8.43 -117 2.6 10.0 10.0 480 30.0 0.06 4.55 10 2.06 54.34 0.3030 8.49 -216 4.2 10.0 10.0 480 30.0 0.06 4.55 10 2.06 54.34 0.3045 8.55 -254 4.0 10.0 10.0 480 30.0 0.06 4.55 10 2.06 54.34 0.3060 8.45 -166 3.1 10.0 10.0 480 30.0 0.06 4.55 10 2.06 54.34 0.3075 8.53 -148 3.3 10.0 10.0 440 30.0 0.06 4.97 11 2.06 58.78 0.2790 8.56 -134 3.3 10.0 10.0 440 30.0 0.06 4.97 11 2.06 58.78 0.27105 8.49 -118 3.2 10.0 10.0 440 30.0 0.06 4.97 11 2.06 58.78 0.27120 8.47 -104 3.4 10.0 10.0 440 30.0 0.06 4.97 11 2.06 58.78 0.27135 8.45 -115 3.5 10.0 10.0 480 40.0 0.06 4.55 10 2.74 53.33 0.30150 8.50 -106 3.5 10.0 10.0 480 40.0 0.06 4.55 10 2.74 53.33 0.30165 8.45 -95 3.5 10.0 10.0 480 40.0 0.06 4.55 10 2.74 53.33 0.30180 8.56 -82 3.4 10.0 10.0 480 40.0 0.06 4.55 10 2.74 53.33 0.30AVG 8.49 -136 22.0 3.4 10.00 10.00 468 33.08 0.06 4.67 11 2.27 55.30 0.29





0

0.5

1

1.5

2

2.5

3

30 60 90 120 150 180

CN(w

ad) (mg/L)

Time (min)

CN(wad) vs Time

0

0.5

1

1.5

2

2.5

3

3.5

4

4.5

5

0 0.5 1 1.5 2 2.5 3

[M] (m

g/L)

CN(wad) (mg/L)

[M] vs CN(wad)

Cu

Ni

Zn

Linear (Cu)

Linear (Ni)

Linear (Zn)

EP1107934

False

CERTIFICATE OF ANALYSISWork Order : EP1107934 Page : 1 of 8

:: LaboratoryClient Environmental Division PerthAMMTEC LTD

: :ContactContact MR WAYNE HARDING Scott James

:: AddressAddress 6 MACADAM PLACE

BALCATTA WESTERN AUSTRALIA 2416

10 Hod Way Malaga WA Australia 6090

:: E-mailE-mail [email protected] [email protected]

:: TelephoneTelephone +61 08 9344 2416 +61-8-9209 7655

:: FacsimileFacsimile +61 08 9345 4688 +61-8-9209 7600

:Project Tetratech QC Level : NEPM 1999 Schedule B(3) and ALS QCS3 requirement

:Order number 098212

:C-O-C number ---- Date Samples Received : 15-NOV-2011

Sampler : ---- Issue Date : 02-DEC-2011

Site : ----

2:No. of samples received

Quote number : EP/570/11 2:No. of samples analysed

This report supersedes any previous report(s) with this reference. Results apply to the sample(s) as submitted. All pages of this report have been checked and approved for

release.

This Certificate of Analysis contains the following information:

l General Comments

l Analytical Results

NATA Accredited Laboratory 825

This document is issued in

accordance with NATA

accreditation requirements.

Accredited for compliance with

ISO/IEC 17025.

SignatoriesThis document has been electronically signed by the authorized signatories indicated below. Electronic signing has been

carried out in compliance with procedures specified in 21 CFR Part 11.

Signatories Accreditation CategoryPosition

Canhuang Ke Metals Instrument Chemist Perth Inorganics

Chas Tucker Inorganic Chemist Perth Inorganics

Daniel Fisher Inorganics Analyst Perth Inorganics

Kim McCabe Senior Inorganic Chemist Brisbane Acid Sulphate Soils

Kim McCabe Senior Inorganic Chemist Stafford Minerals - AY

Leanne Cooper Acid Sulfate Soils Supervisor Perth ASS

Sarah Millington Senior Inorganic Chemist Sydney Inorganics

Wisam Marassa Inorganics Coordinator Sydney Inorganics

Environmental Division Perth


Tel. +61-8-9209 7655 Fax. +61-8-9209 7600 www.alsglobal.com

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General Comments

The analytical procedures used by the Environmental Division have been developed from established internationally recognized procedures such as those published by the USEPA, APHA, AS and NEPM. In house

developed procedures are employed in the absence of documented standards or by client request.

Where moisture determination has been performed, results are reported on a dry weight basis.

Where a reported less than (<) result is higher than the LOR, this may be due to primary sample extract/digestate dilution and/or insuffient sample for analysis.

Where the LOR of a reported result differs from standard LOR, this may be due to high moisture content, insufficient sample (reduced weight employed) or matrix interference.

When sampling time information is not provided by the client, sampling dates are shown without a time component. In these instances, the time component has been assumed by the laboratory for processing purposes.

CAS Number = CAS registry number from database maintained by Chemical Abstracts Services. The Chemical Abstracts Service is a division of the American Chemical Society.

LOR = Limit of reporting

^ = This result is computed from individual analyte detections at or above the level of reporting

Key :

ASS: EA029 (SPOCAS): Liming rate is calculated and reported on a dry weight basis assuming use of fine agricultural lime (CaCO3) and using a safety factor of 1.5 to allow for

non-homogeneous mixing and poor reactivity of lime. For conversion of Liming Rate from kg/t dry weight to kg/m3 in-situ soil, multiply reported results x wet bulk density of soil in

t/m3.

l

ASS: EA033 (CRS Suite): Liming rate is calculated and reported on a dry weight basis assuming use of fine agricultural lime (CaCO3) and using a safety factor of 1.5 to allow for

non-homogeneous mixing and poor reactivity of lime. For conversion of Liming Rate from 'kg/t dry weight' to 'kg/m3 in-situ soil', multiply 'reported results' x 'wet bulk density of soil in

t/m3'.

l

EG020: LCS recoveries for particular element(s) fall outside ALS Dynamic control limit, however, they are within the acceptance criteria based on ALS DQO. No further action is required.l

EG020: LOR for Chromium has been raised in particular sample(s) due to matrix interference(s).l

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Analytical Results

----------------DETOX RESIDUEClient sample IDSub-Matrix: SOIL

----------------[15-NOV-2011]Client sampling date / time

----------------EP1107934-002UnitLORCAS NumberCompound

EA011: Net Acid Generation

pH (OX) ----2.7 ---- ---- ----pH Unit0.1----

NAG (pH 4.5) ----11.6 ---- ---- ----kg H2SO4/t0.1----

NAG (pH 7.0) ----18.2 ---- ---- ----kg H2SO4/t0.1----

EA023 : TOS-ASS

S (HCL) ----0.97 ---- ---- ----%0.02----

Total Oxidisable Sulphur (ASS) ----0.16 ---- ---- ----%0.02----

EA029-A: pH Measurements

pH KCl (23A) ----9.5 ---- ---- ----pH Unit0.1----

pH OX (23B) ----2.9 ---- ---- ----pH Unit0.1----

EA029-B: Acidity Trail

Titratable Actual Acidity (23F) ----<2 ---- ---- ----mole H+ / t2----

Titratable Peroxide Acidity (23G) ----199 ---- ---- ----mole H+ / t2----

Titratable Sulfidic Acidity (23H) ----199 ---- ---- ----mole H+ / t2----

sulfidic - Titratable Actual Acidity (s-23F) ----<0.005 ---- ---- ----% pyrite S0.005----

sulfidic - Titratable Peroxide Acidity

(s-23G)

----0.32 ---- ---- ----% pyrite S0.005----

sulfidic - Titratable Sulfidic Acidity (s-23H) ----0.32 ---- ---- ----% pyrite S0.005----

EA029-C: Sulfur Trail

KCl Extractable Sulfur (23Ce) ----0.04 ---- ---- ----% S0.005----

Peroxide Sulfur (23De) ----0.63 ---- ---- ----% S0.005----

Peroxide Oxidisable Sulfur (23E) ----0.60 ---- ---- ----% S0.005----

acidity - Peroxide Oxidisable Sulfur

(a-23E)

----371 ---- ---- ----mole H+ / t5----

EA029-D: Calcium Values

KCl Extractable Calcium (23Vh) ----0.10 ---- ---- ----% Ca0.005----

Peroxide Calcium (23Wh) ----0.22 ---- ---- ----% Ca0.005----

Acid Reacted Calcium (23X) ----0.13 ---- ---- ----% Ca0.005----

acidity - Acid Reacted Calcium (a-23X) ----61 ---- ---- ----mole H+ / t5----

sulfidic - Acid Reacted Calcium (s-23X) ----0.11 ---- ---- ----% S0.005----

EA029-E: Magnesium Values

KCl Extractable Magnesium (23Sm) ----0.04 ---- ---- ----% Mg0.005----

Peroxide Magnesium (23Tm) ----0.09 ---- ---- ----% Mg0.005----

Acid Reacted Magnesium (23U) ----0.06 ---- ---- ----% Mg0.005----

Acidity - Acid Reacted Magnesium (a-23U) ----46 ---- ---- ----mole H+ / t5----

sulfidic - Acid Reacted Magnesium

(s-23U)

----0.07 ---- ---- ----% S0.005----

EA029-H: Acid Base Accounting

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Analytical Results

----------------DETOX RESIDUEClient sample IDSub-Matrix: SOIL



EA029-H: Acid Base Accounting - Continued

ANC Fineness Factor ----1.5 ---- ---- -----0.5----

Net Acidity (sulfur units) ----0.41 ---- ---- ----% S0.02----

Net Acidity (acidity units) ----256 ---- ---- ----mole H+ / t10----

Liming Rate ----19 ---- ---- ----kg CaCO3/t1----

Net Acidity excluding ANC (sulfur units) ----0.60 ---- ---- ----% S0.02----

Net Acidity excluding ANC (acidity units) ----371 ---- ---- ----mole H+ / t10----

Liming Rate excluding ANC ----28 ---- ---- ----kg CaCO3/t1----

EA033-A: Actual Acidity

pH KCl (23A) ----9.5 ---- ---- ----pH Unit0.1----

Titratable Actual Acidity (23F) ----<2 ---- ---- ----mole H+ / t2----

sulfidic - Titratable Actual Acidity (s-23F) ----<0.02 ---- ---- ----% pyrite S0.02----

EA033-B: Potential Acidity

Chromium Reducible Sulfur (22B) ----0.900 ---- ---- ----% S0.005----

acidity - Chromium Reducible Sulfur

(a-22B)

----561 ---- ---- ----mole H+ / t10----

EA033-C: Acid Neutralising Capacity

Acid Neutralising Capacity (19A2) ----1.44 ---- ---- ----% CaCO30.01----

acidity - Acid Neutralising Capacity

(a-19A2)

----287 ---- ---- ----mole H+ / t10----

sulfidic - Acid Neutralising Capacity

(s-19A2)

----0.46 ---- ---- ----% pyrite S0.01----

EA033-E: Acid Base Accounting

ANC Fineness Factor ----1.5 ---- ---- -----0.5----

Net Acidity (sulfur units) ----0.59 ---- ---- ----% S0.02----

Net Acidity (acidity units) ----370 ---- ---- ----mole H+ / t10----

Liming Rate ----28 ---- ---- ----kg CaCO3/t1----

Net Acidity excluding ANC (sulfur units) ----0.90 ---- ---- ----% S0.02----

Net Acidity excluding ANC (acidity units) ----561 ---- ---- ----mole H+ / t10----

Liming Rate excluding ANC ----42 ---- ---- ----kg CaCO3/t1----

EA055: Moisture Content

Moisture Content (dried @ 103°C) ----<1.0 ---- ---- ----%1.0----

ED040T : Total Sulfate by ICPAES

Sulfate as SO4 2- ----26000 ---- ---- ----mg/kg10014808-79-8

ED042T: Total Sulfur by LECO

Sulfur - Total as S (LECO) ----1.13 ---- ---- ----%0.01----

EK085M: Sulfide as S2-

Sulfide as S ----0.26 ---- ---- ----%0.01----

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Analytical Results

----------------DETOX LIQUORClient sample IDSub-Matrix: WATER



EA005P: pH by PC Titrator

pH Value ----8.78 ---- ---- ----pH Unit0.01----

EA010P: Conductivity by PC Titrator

Electrical Conductivity @ 25°C ----5570 ---- ---- ----µS/cm1----

ED037P: Alkalinity by PC Titrator

Hydroxide Alkalinity as CaCO3 ----<1 ---- ---- ----mg/L1DMO-210-001

Carbonate Alkalinity as CaCO3 ----26 ---- ---- ----mg/L13812-32-6

Bicarbonate Alkalinity as CaCO3 ----162 ---- ---- ----mg/L171-52-3

Total Alkalinity as CaCO3 ----188 ---- ---- ----mg/L1----

ED038A: Acidity

Acidity as CaCO3 ----<1 ---- ---- ----mg/L1----

ED041G: Sulfate (Turbidimetric) as SO4 2- by DA

Sulfate as SO4 - Turbidimetric ----1460 ---- ---- ----mg/L114808-79-8

ED045G: Chloride Discrete analyser

Chloride ----540 ---- ---- ----mg/L116887-00-6

EG020F: Dissolved Metals by ICP-MS

Aluminium ----0.57 ---- ---- ----mg/L0.017429-90-5

Dysprosium ----<0.001 ---- ---- ----mg/L0.0017429-91-6

Silver ----0.456 ---- ---- ----mg/L0.0017440-22-4

Arsenic ----0.489 ---- ---- ----mg/L0.0017440-38-2

Bismuth ----<0.001 ---- ---- ----mg/L0.0017440-69-9

Erbium ----<0.001 ---- ---- ----mg/L0.0017440-52-0

Boron ----0.21 ---- ---- ----mg/L0.057440-42-8

Europium ----<0.001 ---- ---- ----mg/L0.0017440-53-1

Strontium ----0.751 ---- ---- ----mg/L0.0017440-24-6

Barium ----0.071 ---- ---- ----mg/L0.0017440-39-3

Gadolinium ----<0.001 ---- ---- ----mg/L0.0017440-54-2

Titanium ----<0.01 ---- ---- ----mg/L0.017440-32-6

Beryllium ----<0.001 ---- ---- ----mg/L0.0017440-41-7

Gallium ----0.003 ---- ---- ----mg/L0.0017440-55-3

Cadmium ----0.0003 ---- ---- ----mg/L0.00017440-43-9

Hafnium ----<0.01 ---- ---- ----mg/L0.017440-58-6

Tellurium ----<0.005 ---- ---- ----mg/L0.00522541-49-7

Cobalt ----0.521 ---- ---- ----mg/L0.0017440-48-4

Holmium ----<0.001 ---- ---- ----mg/L0.0017440-60-0

Uranium ----0.002 ---- ---- ----mg/L0.0017440-61-1

Caesium ----<0.001 ---- ---- ----mg/L0.0017440-46-2

Chromium ----<0.005 ---- ---- ----mg/L0.0017440-47-3

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Analytical Results




EG020F: Dissolved Metals by ICP-MS - Continued

Indium ----<0.001 ---- ---- ----mg/L0.0017440-74-6

Copper ----1.19 ---- ---- ----mg/L0.0017440-50-8

Lanthanum ----<0.001 ---- ---- ----mg/L0.0017439-91-0

Rubidium ----0.013 ---- ---- ----mg/L0.0017440-17-7

Lithium ----0.002 ---- ---- ----mg/L0.0017439-93-2

Lutetium ----<0.001 ---- ---- ----mg/L0.0017439-94-3

Thorium ----<0.001 ---- ---- ----mg/L0.0017440-29-1

Cerium ----<0.001 ---- ---- ----mg/L0.0017440-45-1

Manganese ----0.007 ---- ---- ----mg/L0.0017439-96-5

Neodymium ----<0.001 ---- ---- ----mg/L0.0017440-00-8

Molybdenum ----0.297 ---- ---- ----mg/L0.0017439-98-7

Praseodymium ----<0.001 ---- ---- ----mg/L0.0017440-10-0

Nickel ----0.004 ---- ---- ----mg/L0.0017440-02-0

Samarium ----<0.001 ---- ---- ----mg/L0.0017440-19-9

Lead ----<0.001 ---- ---- ----mg/L0.0017439-92-1

Terbium ----<0.001 ---- ---- ----mg/L0.0017440-27-9

Antimony ----0.058 ---- ---- ----mg/L0.0017440-36-0

Thulium ----<0.001 ---- ---- ----mg/L0.0017440-30-4

Selenium ----<0.01 ---- ---- ----mg/L0.017782-49-2

Ytterbium ----<0.001 ---- ---- ----mg/L0.0017440-64-4

Tin ----<0.001 ---- ---- ----mg/L0.0017440-31-5

Yttrium ----<0.001 ---- ---- ----mg/L0.0017440-65-5

Thallium ----<0.001 ---- ---- ----mg/L0.0017440-28-0

Zirconium ----<0.005 ---- ---- ----mg/L0.0057440-67-7

Vanadium ----<0.01 ---- ---- ----mg/L0.017440-62-2

Zinc ----0.012 ---- ---- ----mg/L0.0057440-66-6

Iron ----<0.05 ---- ---- ----mg/L0.057439-89-6

EG035F: Dissolved Mercury by FIMS

Mercury ----<0.0001 ---- ---- ----mg/L0.00017439-97-6

EG051G: Ferrous Iron by Discrete Analyser

Ferrous Iron ----0.25 ---- ---- ----mg/L0.05----

EG053FG-MS: Dissolved Ferric Iron by ICPMS and DA

Ferric Iron ----<0.05 ---- ---- ----mg/L0.05----

EK025G: Free cyanide by Discrete Analyser

Free Cyanide ----0.507 ---- ---- ----mg/L0.004----

EK026G: Total Cyanide By Discrete Analyser

Total Cyanide ----26.3 ---- ---- ----mg/L0.00457-12-5

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Analytical Results




EK027: Thiocyanate

Thiocyanate ----252 ---- ---- ----mg/L0.1463-56-9

EK055G: Ammonia as N by Discrete Analyser

Ammonia as N ----114 ---- ---- ----mg/L0.017664-41-7

EK057G: Nitrite as N by Discrete Analyser

Nitrite as N ----0.20 ---- ---- ----mg/L0.01----

EK058G: Nitrate as N by Discrete Analyser

Nitrate as N ----14.0 ---- ---- ----mg/L0.0114797-55-8

EK059G: Nitrite plus Nitrate as N (NOx) by Discrete Analyser

Nitrite + Nitrate as N ----14.2 ---- ---- ----mg/L0.01----

False

QUALITY CONTROL REPORT

Work Order : EP1107934 Page : 1 of 13

:: LaboratoryClient Environmental Division PerthAMMTEC LTD

: :ContactContact MR WAYNE HARDING Scott James




:: E-mailE-mail [email protected] [email protected]

:: TelephoneTelephone +61 08 9344 2416 +61-8-9209 7655

:: FacsimileFacsimile +61 08 9345 4688 +61-8-9209 7600

:Project Tetratech QC Level : NEPM 1999 Schedule B(3) and ALS QCS3 requirement

Site : ----


Sampler : ---- Issue Date : 02-DEC-2011

:Order number 098212

2:No. of samples received

Quote number : EP/570/11 2:No. of samples analysed

This report supersedes any previous report(s) with this reference. Results apply to the sample(s) as submitted. All pages of this report have been checked and approved for

release.

This Quality Control Report contains the following information:

l Laboratory Duplicate (DUP) Report; Relative Percentage Difference (RPD) and Acceptance Limits

l Method Blank (MB) and Laboratory Control Spike (LCS) Report ; Recovery and Acceptance Limits

l Matrix Spike (MS) Report; Recovery and Acceptance Limits

NATA Accredited Laboratory 825

This document is issued in

accordance with NATA

accreditation requirements.

Accredited for compliance with

ISO/IEC 17025.

SignatoriesThis document has been electronically signed by the authorized signatories indicated below. Electronic signing has been

carried out in compliance with procedures specified in 21 CFR Part 11.

Signatories Accreditation CategoryPosition

Canhuang Ke Metals Instrument Chemist Perth Inorganics

Chas Tucker Inorganic Chemist Perth Inorganics

Daniel Fisher Inorganics Analyst Perth Inorganics

Kim McCabe Senior Inorganic Chemist Brisbane Acid Sulphate Soils

Kim McCabe Senior Inorganic Chemist Stafford Minerals - AY

Leanne Cooper Acid Sulfate Soils Supervisor Perth ASS

Sarah Millington Senior Inorganic Chemist Sydney Inorganics

Wisam Marassa Inorganics Coordinator Sydney Inorganics

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General Comments

The analytical procedures used by the Environmental Division have been developed from established internationally recognized procedures such as those published by the USEPA, APHA, AS and NEPM. In house

developed procedures are employed in the absence of documented standards or by client request.

Where moisture determination has been performed, results are reported on a dry weight basis.

Where a reported less than (<) result is higher than the LOR, this may be due to primary sample extract/digestate dilution and/or insuffient sample for analysis.

Where the LOR of a reported result differs from standard LOR, this may be due to high moisture content, insufficient sample (reduced weight employed) or matrix interference.

Anonymous = Refers to samples which are not specifically part of this work order but formed part of the QC process lot

CAS Number = CAS registry number from database maintained by Chemical Abstracts Services. The Chemical Abstracts Service is a division of the American Chemical Society.

LOR = Limit of reporting

RPD = Relative Percentage Difference

# = Indicates failed QC

Key :

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Laboratory Duplicate (DUP) Report

The quality control term Laboratory Duplicate refers to a randomly selected intralaboratory split. Laboratory duplicates provide information regarding method precision and sample heterogeneity. The permitted ranges

for the Relative Percent Deviation (RPD) of Laboratory Duplicates are specified in ALS Method QWI -EN/38 and are dependent on the magnitude of results in comparison to the level of reporting: Result < 10 times LOR:-

No Limit; Result between 10 and 20 times LOR:- 0% - 50%; Result > 20 times LOR:- 0% - 20%.

Sub-Matrix: SOIL Laboratory Duplicate (DUP) Report

Original Result RPD (%)Laboratory sample ID Client sample ID Method: Compound CAS Number LOR Unit Duplicate Result Recovery Limits (%)

EA011: Net Acid Generation (QC Lot: 2045572)

EA011: NAG (pH 4.5) ---- 0.1 kg H2SO4/t 11.6 11.8 1.4 0% - 20%DETOX RESIDUEEP1107934-002

EA011: NAG (pH 7.0) ---- 0.1 kg H2SO4/t 18.2 19.8 8.3 0% - 20%

EA011: pH (OX) ---- 0.1 pH Unit 2.7 2.7 0.0 0% - 20%

EA023 : TOS-ASS (QC Lot: 2052355)

EA023SHCl: S (HCL) ---- 0.02 % 0.97 0.88 9.2 0% - 20%DETOX RESIDUEEP1107934-002

EA029-A: pH Measurements (QC Lot: 2045573)

EA029: pH KCl (23A) ---- 0.1 pH Unit 9.5 9.5 0.0 0% - 20%DETOX RESIDUEEP1107934-002

EA029: pH OX (23B) ---- 0.1 pH Unit 2.9 2.9 0.0 0% - 20%

EA029-B: Acidity Trail (QC Lot: 2045573)

EA029: sulfidic - Titratable Actual Acidity (s-23F) ---- 0.005 % pyrite S <0.005 <0.005 0.0 No LimitDETOX RESIDUEEP1107934-002

EA029: sulfidic - Titratable Peroxide Acidity

(s-23G)

---- 0.005 % pyrite S 0.32 0.32 0.0 0% - 20%

EA029: sulfidic - Titratable Sulfidic Acidity

(s-23H)

---- 0.005 % pyrite S 0.32 0.32 0.0 0% - 20%

EA029: Titratable Actual Acidity (23F) ---- 2 mole H+ / t <2 <2 0.0 No Limit

EA029: Titratable Peroxide Acidity (23G) ---- 2 mole H+ / t 199 199 0.0 0% - 20%

EA029: Titratable Sulfidic Acidity (23H) ---- 2 mole H+ / t 199 199 0.0 0% - 20%

EA029-C: Sulfur Trail (QC Lot: 2045573)

EA029: KCl Extractable Sulfur (23Ce) ---- 0.005 % S 0.04 0.03 0.0 No LimitDETOX RESIDUEEP1107934-002

EA029: Peroxide Sulfur (23De) ---- 0.005 % S 0.63 0.67 6.2 0% - 20%

EA029: Peroxide Oxidisable Sulfur (23E) ---- 0.005 % S 0.60 0.64 7.1 0% - 20%

EA029: acidity - Peroxide Oxidisable Sulfur

(a-23E)

---- 5 mole H+ / t 371 399 7.1 0% - 20%

EA029-D: Calcium Values (QC Lot: 2045573)

EA029: KCl Extractable Calcium (23Vh) ---- 0.005 % Ca 0.10 0.09 11.7 0% - 50%DETOX RESIDUEEP1107934-002

EA029: Peroxide Calcium (23Wh) ---- 0.005 % Ca 0.22 0.24 7.2 0% - 20%

EA029: Acid Reacted Calcium (23X) ---- 0.005 % Ca 0.13 0.14 0.0 0% - 20%

EA029: sulfidic - Acid Reacted Calcium (s-23X) ---- 0.005 % S 0.11 0.11 0.0 0% - 20%

EA029: acidity - Acid Reacted Calcium (a-23X) ---- 5 mole H+ / t 61 75 20.0 0% - 50%

EA029-E: Magnesium Values (QC Lot: 2045573)

EA029: KCl Extractable Magnesium (23Sm) ---- 0.005 % Mg 0.04 0.03 0.0 No LimitDETOX RESIDUEEP1107934-002

EA029: Peroxide Magnesium (23Tm) ---- 0.005 % Mg 0.09 0.10 0.0 0% - 20%

EA029: Acid Reacted Magnesium (23U) ---- 0.005 % Mg 0.06 0.06 0.0 0% - 50%

EA029: sulfidic - Acid Reacted Magnesium

(s-23U)

---- 0.005 % S 0.07 0.08 13.8 0% - 50%

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Sub-Matrix: SOIL Laboratory Duplicate (DUP) Report


EA029-E: Magnesium Values (QC Lot: 2045573) - continued

EA029: Acidity - Acid Reacted Magnesium

(a-23U)

---- 5 mole H+ / t 46 53 13.8 0% - 50%DETOX RESIDUEEP1107934-002

EA029-H: Acid Base Accounting (QC Lot: 2045573)

EA029: ANC Fineness Factor ---- 0.5 - 1.5 1.5 0.0 No LimitDETOX RESIDUEEP1107934-002

EA029: Net Acidity (sulfur units) ---- 0.02 % S 0.41 0.42 3.5 0% - 20%

EA029: Net Acidity excluding ANC (sulfur units) ---- 0.02 % S 0.60 0.64 7.1 0% - 20%

EA029: Liming Rate ---- 1 kg CaCO3/t 19 20 0.0 0% - 20%

EA029: Liming Rate excluding ANC ---- 1 kg CaCO3/t 28 30 7.1 0% - 20%

EA029: Net Acidity (acidity units) ---- 10 mole H+ / t 256 265 3.5 0% - 20%

EA029: Net Acidity excluding ANC (acidity units) ---- 10 mole H+ / t 371 399 7.1 0% - 20%

EA033-A: Actual Acidity (QC Lot: 2045574)

EA033: sulfidic - Titratable Actual Acidity (s-23F) ---- 0.02 % pyrite S <0.02 <0.02 0.0 No LimitDETOX RESIDUEEP1107934-002

EA033: Titratable Actual Acidity (23F) ---- 2 mole H+ / t <2 <2 0.0 No Limit

EA033: pH KCl (23A) ---- 0.1 pH Unit 9.5 9.5 0.0 0% - 20%

EA033-B: Potential Acidity (QC Lot: 2045574)

EA033: Chromium Reducible Sulfur (22B) ---- 0.005 % S 0.900 0.888 1.3 0% - 20%DETOX RESIDUEEP1107934-002

EA033: acidity - Chromium Reducible Sulfur

(a-22B)

---- 10 mole H+ / t 561 554 1.3 0% - 20%

EA033-C: Acid Neutralising Capacity (QC Lot: 2045574)

EA033: Acid Neutralising Capacity (19A2) ---- 0.01 % CaCO3 1.44 1.44 0.0 0% - 20%DETOX RESIDUEEP1107934-002

EA033: sulfidic - Acid Neutralising Capacity

(s-19A2)

---- 0.01 % pyrite S 0.46 0.46 0.0 0% - 20%

EA033: acidity - Acid Neutralising Capacity

(a-19A2)

---- 10 mole H+ / t 287 287 0.0 0% - 20%

EA033-E: Acid Base Accounting (QC Lot: 2045574)

EA033: ANC Fineness Factor ---- 0.5 - 1.5 1.5 0.0 No LimitDETOX RESIDUEEP1107934-002

EA033: Net Acidity (sulfur units) ---- 0.02 % S 0.59 0.58 1.9 0% - 20%

EA033: Net Acidity excluding ANC (sulfur units) ---- 0.02 % S 0.90 0.89 1.3 0% - 20%

EA033: Liming Rate ---- 1 kg CaCO3/t 28 27 0.0 0% - 20%

EA033: Liming Rate excluding ANC ---- 1 kg CaCO3/t 42 42 0.0 0% - 20%

EA033: Net Acidity (acidity units) ---- 10 mole H+ / t 370 362 1.9 0% - 20%

EA033: Net Acidity excluding ANC (acidity units) ---- 10 mole H+ / t 561 554 1.3 0% - 20%

EA055: Moisture Content (QC Lot: 2052374)

EA055-103: Moisture Content (dried @ 103°C) ---- 1.0 % 24.3 23.7 2.6 0% - 20%AnonymousEP1107872-001

EA055-103: Moisture Content (dried @ 103°C) ---- 1.0 % 4.4 4.5 0.0 No LimitAnonymousEP1107961-003

ED040T : Total Sulfate by ICPAES (QC Lot: 2057103)

ED040T: Sulfate as SO4 2- 14808-79-8 100 mg/kg 26000 27000 3.9 0% - 20%DETOX RESIDUEEP1107934-002

ED042T: Total Sulfur by LECO (QC Lot: 2052354)

ED042T: Sulfur - Total as S (LECO) ---- 0.01 % 1.13 1.15 2.1 0% - 20%DETOX RESIDUEEP1107934-002

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Sub-Matrix: WATER Laboratory Duplicate (DUP) Report


EA005P: pH by PC Titrator (QC Lot: 2045606)

EA005-P: pH Value ---- 0.01 pH Unit 7.93 7.93 0.0 0% - 20%AnonymousEP1107930-001

EA010P: Conductivity by PC Titrator (QC Lot: 2045603)

EA010-P: Electrical Conductivity @ 25°C ---- 1 µS/cm 2380 2380 0.0 0% - 20%AnonymousEP1107919-003

EA010-P: Electrical Conductivity @ 25°C ---- 1 µS/cm 665 662 0.4 0% - 20%AnonymousEP1107930-001

ED037P: Alkalinity by PC Titrator (QC Lot: 2045607)

ED037-P: Hydroxide Alkalinity as CaCO3 DMO-210-001 1 mg/L <1 <1 0.0 No LimitAnonymousEP1107930-001

ED037-P: Carbonate Alkalinity as CaCO3 3812-32-6 1 mg/L <1 <1 0.0 No Limit

ED037-P: Bicarbonate Alkalinity as CaCO3 71-52-3 1 mg/L 252 252 0.0 0% - 20%

ED037-P: Total Alkalinity as CaCO3 ---- 1 mg/L 252 252 0.0 0% - 20%

ED038A: Acidity (QC Lot: 2052539)

ED038: Acidity as CaCO3 ---- 1 mg/L <1 <1 0.0 No LimitDETOX LIQUOREP1107934-001

ED038: Acidity as CaCO3 ---- 1 mg/L <1 <1 0.0 No LimitAnonymousEP1108010-001

ED041G: Sulfate (Turbidimetric) as SO4 2- by DA (QC Lot: 2046745)

ED041G: Sulfate as SO4 - Turbidimetric 14808-79-8 1 mg/L 138 141 2.4 0% - 20%AnonymousEP1107930-003

ED041G: Sulfate as SO4 - Turbidimetric 14808-79-8 1 mg/L 3 3 0.0 No LimitAnonymousEP1107932-007

ED045G: Chloride Discrete analyser (QC Lot: 2046742)

ED045G: Chloride 16887-00-6 1 mg/L 366 367 0.3 0% - 20%AnonymousEP1107926-009

EG020F: Dissolved Metals by ICP-MS (QC Lot: 2061099)

EG020A-F: Cadmium 7440-43-9 0.0001 mg/L 0.0003 0.0003 0.0 No LimitDETOX LIQUOREP1107934-001

EG020A-F: Antimony 7440-36-0 0.001 mg/L 0.058 0.058 0.0 0% - 20%

EG020A-F: Arsenic 7440-38-2 0.001 mg/L 0.489 0.476 2.7 0% - 20%

EG020A-F: Beryllium 7440-41-7 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Barium 7440-39-3 0.001 mg/L 0.071 0.072 0.0 0% - 20%

EG020A-F: Chromium 7440-47-3 0.001 mg/L <0.005 <0.005 0.0 No Limit

EG020A-F: Cobalt 7440-48-4 0.001 mg/L 0.521 0.533 2.3 0% - 20%

EG020A-F: Copper 7440-50-8 0.001 mg/L 1.19 1.15 3.2 0% - 20%

EG020A-F: Lead 7439-92-1 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Lithium 7439-93-2 0.001 mg/L 0.002 0.002 0.0 No Limit

EG020A-F: Manganese 7439-96-5 0.001 mg/L 0.007 0.007 0.0 No Limit

EG020A-F: Molybdenum 7439-98-7 0.001 mg/L 0.297 0.297 0.0 0% - 20%

EG020A-F: Nickel 7440-02-0 0.001 mg/L 0.004 0.005 0.0 No Limit

EG020A-F: Thallium 7440-28-0 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Tin 7440-31-5 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Zinc 7440-66-6 0.005 mg/L 0.012 0.013 9.3 No Limit

EG020A-F: Aluminium 7429-90-5 0.01 mg/L 0.57 0.55 3.6 0% - 20%

EG020A-F: Selenium 7782-49-2 0.01 mg/L <0.01 <0.01 0.0 No Limit

EG020A-F: Vanadium 7440-62-2 0.01 mg/L <0.01 <0.01 0.0 No Limit

EG020A-F: Boron 7440-42-8 0.05 mg/L 0.21 0.21 0.0 No Limit

EG020A-F: Iron 7439-89-6 0.05 mg/L <0.05 <0.05 0.0 No Limit

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EG020F: Dissolved Metals by ICP-MS (QC Lot: 2061099) - continued

EG020A-F: Cadmium 7440-43-9 0.0001 mg/L <0.0001 <0.0001 0.0 No LimitAnonymousES1125647-003

EG020A-F: Antimony 7440-36-0 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Arsenic 7440-38-2 0.001 mg/L 0.097 0.098 1.0 0% - 20%

EG020A-F: Beryllium 7440-41-7 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Barium 7440-39-3 0.001 mg/L 0.017 0.016 0.0 0% - 50%

EG020A-F: Chromium 7440-47-3 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Cobalt 7440-48-4 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Copper 7440-50-8 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Lead 7439-92-1 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Lithium 7439-93-2 0.001 mg/L 0.006 0.006 0.0 No Limit

EG020A-F: Manganese 7439-96-5 0.001 mg/L 0.056 0.054 3.6 0% - 20%

EG020A-F: Molybdenum 7439-98-7 0.001 mg/L 0.018 0.018 0.0 0% - 50%

EG020A-F: Nickel 7440-02-0 0.001 mg/L 0.002 0.002 0.0 No Limit

EG020A-F: Thallium 7440-28-0 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Tin 7440-31-5 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020A-F: Zinc 7440-66-6 0.005 mg/L <0.005 <0.005 0.0 No Limit

EG020A-F: Aluminium 7429-90-5 0.01 mg/L <0.01 <0.01 0.0 No Limit

EG020A-F: Selenium 7782-49-2 0.01 mg/L <0.01 <0.01 0.0 No Limit

EG020A-F: Vanadium 7440-62-2 0.01 mg/L <0.01 <0.01 0.0 No Limit

EG020A-F: Boron 7440-42-8 0.05 mg/L 0.09 0.09 0.0 No Limit

EG020A-F: Iron 7439-89-6 0.05 mg/L <0.05 <0.05 0.0 No Limit


EG020B-F: Bismuth 7440-69-9 0.001 mg/L <0.001 <0.001 0.0 No LimitDETOX LIQUOREP1107934-001

EG020B-F: Cerium 7440-45-1 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020B-F: Caesium 7440-46-2 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020B-F: Rubidium 7440-17-7 0.001 mg/L 0.013 0.013 0.0 0% - 50%

EG020B-F: Silver 7440-22-4 0.001 mg/L 0.456 0.525 14.0 0% - 20%

EG020B-F: Strontium 7440-24-6 0.001 mg/L 0.751 0.764 1.6 0% - 20%

EG020B-F: Thorium 7440-29-1 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020B-F: Uranium 7440-61-1 0.001 mg/L 0.002 0.002 0.0 No Limit

EG020B-F: Tellurium 22541-49-7 0.005 mg/L <0.005 <0.005 0.0 No Limit

EG020B-F: Titanium 7440-32-6 0.01 mg/L <0.01 <0.01 0.0 No Limit

EG020B-F: Bismuth 7440-69-9 0.001 mg/L <0.001 <0.001 0.0 No LimitAnonymousES1125647-003

EG020B-F: Cerium 7440-45-1 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020B-F: Caesium 7440-46-2 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020B-F: Rubidium 7440-17-7 0.001 mg/L 0.002 0.002 0.0 No Limit

EG020B-F: Silver 7440-22-4 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020B-F: Strontium 7440-24-6 0.001 mg/L 2.93 2.94 0.5 0% - 20%

EG020B-F: Thorium 7440-29-1 0.001 mg/L <0.001 <0.001 0.0 No Limit

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EG020B-F: Uranium 7440-61-1 0.001 mg/L <0.001 <0.001 0.0 No LimitAnonymousES1125647-003

EG020B-F: Tellurium 22541-49-7 0.005 mg/L <0.005 <0.005 0.0 No Limit

EG020B-F: Titanium 7440-32-6 0.01 mg/L <0.01 <0.01 0.0 No Limit


EG020D-F: Dysprosium 7429-91-6 0.001 mg/L <0.001 <0.001 0.0 No LimitDETOX LIQUOREP1107934-001

EG020D-F: Erbium 7440-52-0 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Europium 7440-53-1 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Gadolinium 7440-54-2 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Gallium 7440-55-3 0.001 mg/L 0.003 0.003 0.0 No Limit

EG020D-F: Holmium 7440-60-0 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Indium 7440-74-6 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Lanthanum 7439-91-0 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Lutetium 7439-94-3 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Neodymium 7440-00-8 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Praseodymium 7440-10-0 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Samarium 7440-19-9 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Terbium 7440-27-9 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Thulium 7440-30-4 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Ytterbium 7440-64-4 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Yttrium 7440-65-5 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Zirconium 7440-67-7 0.005 mg/L <0.005 <0.005 0.0 No Limit

EG020D-F: Hafnium 7440-58-6 0.01 mg/L <0.01 <0.01 0.0 No Limit

EG020D-F: Dysprosium 7429-91-6 0.001 mg/L <0.001 <0.001 0.0 No LimitAnonymousES1125647-003

EG020D-F: Erbium 7440-52-0 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Europium 7440-53-1 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Gadolinium 7440-54-2 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Gallium 7440-55-3 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Holmium 7440-60-0 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Indium 7440-74-6 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Lanthanum 7439-91-0 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Lutetium 7439-94-3 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Neodymium 7440-00-8 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Praseodymium 7440-10-0 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Samarium 7440-19-9 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Terbium 7440-27-9 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Thulium 7440-30-4 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Ytterbium 7440-64-4 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Yttrium 7440-65-5 0.001 mg/L <0.001 <0.001 0.0 No Limit

EG020D-F: Zirconium 7440-67-7 0.005 mg/L <0.005 <0.005 0.0 No Limit

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EG020D-F: Hafnium 7440-58-6 0.01 mg/L <0.01 <0.01 0.0 No LimitAnonymousES1125647-003

EG035F: Dissolved Mercury by FIMS (QC Lot: 2061098)

EG035F: Mercury 7439-97-6 0.0001 mg/L <0.0001 <0.0001 0.0 No LimitAnonymousES1125647-001

EG035F: Mercury 7439-97-6 0.0001 mg/L <0.0001 <0.0001 0.0 No LimitAnonymousES1125647-010

EG051G: Ferrous Iron by Discrete Analyser (QC Lot: 2046352)

EG051G: Ferrous Iron ---- 0.05 mg/L 0.47 0.38 19.4 No LimitAnonymousEP1107932-001

EG051G: Ferrous Iron ---- 0.05 mg/L 0.25 0.25 0.0 No LimitDETOX LIQUOREP1107934-001

EK025G: Free cyanide by Discrete Analyser (QC Lot: 2058377)

EK025G: Free Cyanide ---- 0.004 mg/L 0.507 0.508 0.2 0% - 20%DETOX LIQUOREP1107934-001

EK026G: Total Cyanide By Discrete Analyser (QC Lot: 2058366)

EK026G: Total Cyanide 57-12-5 0.004 mg/L 26.3 25.2 4.2 0% - 20%DETOX LIQUOREP1107934-001

EK027: Thiocyanate (QC Lot: 2049125)

EK027: Thiocyanate 463-56-9 0.1 mg/L 252 252 0.04 0% - 20%DETOX LIQUOREP1107934-001

EK055G: Ammonia as N by Discrete Analyser (QC Lot: 2068012)

EK055G: Ammonia as N 7664-41-7 0.01 mg/L 114 116 2.2 0% - 20%DETOX LIQUOREP1107934-001

EK055G: Ammonia as N 7664-41-7 0.01 mg/L 0.04 0.04 0.0 No LimitAnonymousEP1108210-002

EK057G: Nitrite as N by Discrete Analyser (QC Lot: 2046743)

EK057G: Nitrite as N ---- 0.01 mg/L <0.01 <0.01 0.0 No LimitAnonymousEP1107929-010

EK059G: Nitrite plus Nitrate as N (NOx) by Discrete Analyser (QC Lot: 2068011)

EK059G: Nitrite + Nitrate as N ---- 0.01 mg/L 14.2 14.6 2.9 0% - 20%DETOX LIQUOREP1107934-001

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Method Blank (MB) and Laboratory Control Spike (LCS) Report

The quality control term Method / Laboratory Blank refers to an analyte free matrix to which all reagents are added in the same volumes or proportions as used in standard sample preparation. The purpose of this QC

parameter is to monitor potential laboratory contamination. The quality control term Laboratory Control Sample (LCS) refers to a certified reference material, or a known interference free matrix spiked with target

analytes. The purpose of this QC parameter is to monitor method precision and accuracy independent of sample matrix. Dynamic Recovery Limits are based on statistical evaluation of processed LCS.

Sub-Matrix: SOIL Method Blank (MB)

Report

Laboratory Control Spike (LCS) Report

Spike Spike Recovery (%) Recovery Limits (%)

Result Concentration HighLowLCSMethod: Compound CAS Number LOR Unit

EA011: Net Acid Generation (QCLot: 2045572)

EA011: NAG (pH 7.0) ---- 0.1 kg H2SO4/t ---- 99.122.52 kg H2SO4/t 11490

EA023 : TOS-ASS (QCLot: 2052355)

EA023SHCl: S (HCL) ---- 5 % <5.00 -------- --------

EA029-A: pH Measurements (QCLot: 2045573)

EA029: pH KCl (23A) ---- 0.1 pH Unit ---- 1007 pH Unit 13070

EA029: pH OX (23B) ---- 0.1 pH Unit ---- 1007 pH Unit 13070

EA029-B: Acidity Trail (QCLot: 2045573)

EA029: Titratable Actual Acidity (23F) ---- 2 mole H+ / t <2 97.9116.215 mole H+ / t 13070

EA029: Titratable Peroxide Acidity (23G) ---- 2 mole H+ / t <2 10473.7217 mole H+ / t 13070

EA029: sulfidic - Titratable Actual Acidity (s-23F) ---- 0.005 % pyrite S <0.005 -------- --------

EA029: sulfidic - Titratable Peroxide Acidity (s-23G) ---- 0.005 % pyrite S <0.005 -------- --------

EA029: sulfidic - Titratable Sulfidic Acidity (s-23H) ---- 0.005 % pyrite S <0.005 -------- --------

EA029-C: Sulfur Trail (QCLot: 2045573)

EA029: KCl Extractable Sulfur (23Ce) ---- 0.005 % S <0.005 100.17446 % S 13070

EA029: Peroxide Sulfur (23De) ---- 0.005 % S <0.005 99.60.19944 % S 13070

EA029: Peroxide Oxidisable Sulfur (23E) ---- 0.005 % S <0.005 -------- --------

EA029: acidity - Peroxide Oxidisable Sulfur (a-23E) ---- 5 mole H+ / t <5 -------- --------

EA029-D: Calcium Values (QCLot: 2045573)

EA029: KCl Extractable Calcium (23Vh) ---- 0.005 % Ca <0.005 93.6.13447 % Ca 13070

EA029: Peroxide Calcium (23Wh) ---- 0.005 % Ca <0.005 1010.14465 % Ca 13070

EA029: Acid Reacted Calcium (23X) ---- 0.005 % Ca <0.005 -------- --------

EA029: acidity - Acid Reacted Calcium (a-23X) ---- 5 mole H+ / t <5 -------- --------

EA029: sulfidic - Acid Reacted Calcium (s-23X) ---- 0.005 % S <0.005 -------- --------

EA029-E: Magnesium Values (QCLot: 2045573)

EA029: KCl Extractable Magnesium (23Sm) ---- 0.005 % Mg <0.005 96.1.20363 % Mg 13070

EA029: Peroxide Magnesium (23Tm) ---- 0.005 % Mg <0.005 99.60.22829 % Mg 13070

EA029: Acid Reacted Magnesium (23U) ---- 0.005 % Mg <0.005 -------- --------

EA029: Acidity - Acid Reacted Magnesium (a-23U) ---- 5 mole H+ / t <5 -------- --------

EA029: sulfidic - Acid Reacted Magnesium (s-23U) ---- 0.005 % S <0.005 -------- --------

EA033-A: Actual Acidity (QCLot: 2045574)

EA033: pH KCl (23A) ---- 0.1 pH Unit <0.1 -------- --------

EA033: Titratable Actual Acidity (23F) ---- 2 mole H+ / t <2 97.9116.215 mole H+ / t 13070

EA033: sulfidic - Titratable Actual Acidity (s-23F) ---- 0.02 % pyrite S <0.02 -------- --------

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Sub-Matrix: SOIL Method Blank (MB)

Report




EA033-B: Potential Acidity (QCLot: 2045574)

EA033: Chromium Reducible Sulfur (22B) ---- 0.005 % S <0.005 90.9.199 % S 13070

EA033: acidity - Chromium Reducible Sulfur (a-22B) ---- 10 mole H+ / t <10 -------- --------

EA033-C: Acid Neutralising Capacity (QCLot: 2045574)

EA033: Acid Neutralising Capacity (19A2) ---- 0.01 % CaCO3 <0.01 99.84.9 % CaCO3 13070

EA033: acidity - Acid Neutralising Capacity (a-19A2) ---- 10 mole H+ / t <10 -------- --------

EA033: sulfidic - Acid Neutralising Capacity (s-19A2) ---- 0.01 % pyrite S <0.01 -------- --------

EA033-E: Acid Base Accounting (QCLot: 2045574)

EA033: ANC Fineness Factor ---- 0.5 <0.5 -------- --------

EA033: Net Acidity (sulfur units) ---- 0.02 % S <0.02 -------- --------

EA033: Net Acidity (acidity units) ---- 10 mole H+ / t <10 -------- --------

EA033: Liming Rate ---- 1 kg CaCO3/t <1 -------- --------

ED040T : Total Sulfate by ICPAES (QCLot: 2057103)

ED040T: Sulfate as SO4 2- 14808-79-8 100 mg/kg <100 -------- --------

ED042T: Total Sulfur by LECO (QCLot: 2052354)

ED042T: Sulfur - Total as S (LECO) ---- 0.01 % <0.01 99.5100 % 13070

Sub-Matrix: WATER Method Blank (MB)

Report




EA005P: pH by PC Titrator (QCLot: 2045606)

EA005-P: pH Value ---- 0.01 pH Unit ---- 99.27.00 pH Unit 13070

EA010P: Conductivity by PC Titrator (QCLot: 2045603)

EA010-P: Electrical Conductivity @ 25°C ---- 1 µS/cm <1 1024000 µS/cm 10793.2

ED037P: Alkalinity by PC Titrator (QCLot: 2045607)

ED037-P: Hydroxide Alkalinity as CaCO3 DMO-210-00

1

1 mg/L <1 -------- --------

ED037-P: Carbonate Alkalinity as CaCO3 3812-32-6 1 mg/L <1 -------- --------

ED037-P: Bicarbonate Alkalinity as CaCO3 71-52-3 1 mg/L <1 -------- --------

ED037-P: Total Alkalinity as CaCO3 ---- 1 mg/L <1 101200 mg/L 10892

ED038A: Acidity (QCLot: 2052539)

ED038: Acidity as CaCO3 ---- 1 mg/L ---- 97.620 mg/L 11985

ED041G: Sulfate (Turbidimetric) as SO4 2- by DA (QCLot: 2046745)

ED041G: Sulfate as SO4 - Turbidimetric 14808-79-8 1 mg/L <1 11225 mg/L 13085

ED045G: Chloride Discrete analyser (QCLot: 2046742)

ED045G: Chloride 16887-00-6 1 mg/L <1 96.41000 mg/L 13078

EG020F: Dissolved Metals by ICP-MS (QCLot: 2061099)

EG020A-F: Aluminium 7429-90-5 0.01 mg/L <0.01 # 1210.5 mg/L 11292

EG020A-F: Antimony 7440-36-0 0.001 mg/L <0.001 -------- --------

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EG020F: Dissolved Metals by ICP-MS (QCLot: 2061099) - continued

EG020A-F: Arsenic 7440-38-2 0.001 mg/L <0.001 89.60.1 mg/L 11088

EG020A-F: Beryllium 7440-41-7 0.001 mg/L <0.001 87.10.1 mg/L 11480

EG020A-F: Barium 7440-39-3 0.001 mg/L <0.001 96.10.1 mg/L 10985

EG020A-F: Cadmium 7440-43-9 0.0001 mg/L <0.0001 92.10.1 mg/L 10789

EG020A-F: Chromium 7440-47-3 0.001 mg/L <0.001 94.00.1 mg/L 11191

EG020A-F: Cobalt 7440-48-4 0.001 mg/L <0.001 93.80.1 mg/L 10989

EG020A-F: Copper 7440-50-8 0.001 mg/L <0.001 94.60.1 mg/L 11187

EG020A-F: Lead 7439-92-1 0.001 mg/L <0.001 # 89.10.1 mg/L 11090

EG020A-F: Lithium 7439-93-2 0.001 mg/L <0.001 90.00.1 mg/L 11480

EG020A-F: Manganese 7439-96-5 0.001 mg/L <0.001 99.60.1 mg/L 11387

EG020A-F: Molybdenum 7439-98-7 0.001 mg/L <0.001 94.00.1 mg/L 11484

EG020A-F: Nickel 7440-02-0 0.001 mg/L <0.001 94.60.1 mg/L 10989

EG020A-F: Selenium 7782-49-2 0.01 mg/L <0.01 87.40.1 mg/L 11979

EG020A-F: Thallium 7440-28-0 0.001 mg/L <0.001 89.60.1 mg/L 11088

EG020A-F: Tin 7440-31-5 0.001 mg/L <0.001 93.40.1 mg/L 11381

EG020A-F: Vanadium 7440-62-2 0.01 mg/L <0.01 # 79.70.1 mg/L 10991

EG020A-F: Zinc 7440-66-6 0.005 mg/L <0.005 86.30.1 mg/L 11585

EG020A-F: Boron 7440-42-8 0.05 mg/L <0.05 96.50.1 mg/L 12771

EG020A-F: Iron 7439-89-6 0.05 mg/L <0.05 88.10.5 mg/L 11484


EG020B-F: Bismuth 7440-69-9 0.001 mg/L <0.001 1130.1 mg/L 11474

EG020B-F: Cerium 7440-45-1 0.001 mg/L <0.001 -------- --------

EG020B-F: Caesium 7440-46-2 0.001 mg/L <0.001 -------- --------

EG020B-F: Rubidium 7440-17-7 0.001 mg/L <0.001 -------- --------

EG020B-F: Silver 7440-22-4 0.001 mg/L <0.001 -------- --------

EG020B-F: Strontium 7440-24-6 0.001 mg/L <0.001 97.20.1 mg/L 11288

EG020B-F: Tellurium 22541-49-7 0.005 mg/L <0.005 # 87.60.1 mg/L 10688

EG020B-F: Thorium 7440-29-1 0.001 mg/L <0.001 -------- --------

EG020B-F: Titanium 7440-32-6 0.01 mg/L <0.01 # 87.60.1 mg/L 11288

EG020B-F: Uranium 7440-61-1 0.001 mg/L <0.001 -------- --------


EG020D-F: Dysprosium 7429-91-6 0.001 mg/L <0.001 -------- --------

EG020D-F: Erbium 7440-52-0 0.001 mg/L <0.001 -------- --------

EG020D-F: Europium 7440-53-1 0.001 mg/L <0.001 -------- --------

EG020D-F: Gadolinium 7440-54-2 0.001 mg/L <0.001 -------- --------

EG020D-F: Gallium 7440-55-3 0.001 mg/L <0.001 -------- --------

EG020D-F: Hafnium 7440-58-6 0.01 mg/L <0.01 -------- --------

EG020D-F: Holmium 7440-60-0 0.001 mg/L <0.001 -------- --------

EG020D-F: Indium 7440-74-6 0.001 mg/L <0.001 -------- --------

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EG020F: Dissolved Metals by ICP-MS (QCLot: 2061101) - continued

EG020D-F: Lanthanum 7439-91-0 0.001 mg/L <0.001 -------- --------

EG020D-F: Lutetium 7439-94-3 0.001 mg/L <0.001 -------- --------

EG020D-F: Neodymium 7440-00-8 0.001 mg/L <0.001 -------- --------

EG020D-F: Praseodymium 7440-10-0 0.001 mg/L <0.001 -------- --------

EG020D-F: Samarium 7440-19-9 0.001 mg/L <0.001 -------- --------

EG020D-F: Terbium 7440-27-9 0.001 mg/L <0.001 -------- --------

EG020D-F: Thulium 7440-30-4 0.001 mg/L <0.001 -------- --------

EG020D-F: Ytterbium 7440-64-4 0.001 mg/L <0.001 -------- --------

EG020D-F: Yttrium 7440-65-5 0.001 mg/L <0.001 -------- --------

EG020D-F: Zirconium 7440-67-7 0.005 mg/L <0.005 -------- --------

EG035F: Dissolved Mercury by FIMS (QCLot: 2061098)

EG035F: Mercury 7439-97-6 0.0001 mg/L <0.0001 93.30.010 mg/L 11686

EG051G: Ferrous Iron by Discrete Analyser (QCLot: 2046352)

EG051G: Ferrous Iron ---- 0.05 mg/L <0.05 1032.00 mg/L 11187

EK025G: Free cyanide by Discrete Analyser (QCLot: 2058377)

EK025G: Free Cyanide ---- 0.004 mg/L <0.004 93.00.20 mg/L 12664.3

EK026G: Total Cyanide By Discrete Analyser (QCLot: 2058366)

EK026G: Total Cyanide 57-12-5 0.004 mg/L <0.004 1020.500 mg/L 12272

EK027: Thiocyanate (QCLot: 2049125)

EK027: Thiocyanate 463-56-9 0.1 mg/L <0.1 83.25.0 mg/L 13070

EK055G: Ammonia as N by Discrete Analyser (QCLot: 2068012)

EK055G: Ammonia as N 7664-41-7 0.01 mg/L <0.01 1041 mg/L 12487.5

EK057G: Nitrite as N by Discrete Analyser (QCLot: 2046743)

EK057G: Nitrite as N ---- 0.01 mg/L <0.01 98.60.5 mg/L 12486

EK059G: Nitrite plus Nitrate as N (NOx) by Discrete Analyser (QCLot: 2068011)

EK059G: Nitrite + Nitrate as N ---- 0.01 mg/L <0.01 1030.96 mg/L 12475.6

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Matrix Spike (MS) Report

The quality control term Matrix Spike (MS) refers to an intralaboratory split sample spiked with a representative set of target analytes. The purpose of this QC parameter is to monitor potential matrix effects on analyte

recoveries. Static Recovery Limits as per laboratory Data Quality Objectives (DQOs). Ideal recovery ranges stated may be waived in the event of sample matrix interference.

Sub-Matrix: WATER Matrix Spike (MS) Report

Spike Recovery (%) Recovery Limits (%)Spike

HighLowMSConcentrationLaboratory sample ID Client sample ID Method: Compound CAS Number

ED041G: Sulfate (Turbidimetric) as SO4 2- by DA (QCLot: 2046745)

AnonymousEP1107930-003 14808-79-8ED041G: Sulfate as SO4 - Turbidimetric 71.4100 mg/L 13070

ED045G: Chloride Discrete analyser (QCLot: 2046742)

AnonymousEP1107926-009 16887-00-6ED045G: Chloride 88.3250 mg/L 13070


DETOX LIQUOREP1107934-001 7440-38-2EG020A-F: Arsenic 1280.2 mg/L 13070

7440-41-7EG020A-F: Beryllium 82.60.2 mg/L 13070

7440-39-3EG020A-F: Barium 86.20.2 mg/L 13070

7440-43-9EG020A-F: Cadmium 83.20.05 mg/L 13070

7440-47-3EG020A-F: Chromium 95.70.2 mg/L 13070

7440-48-4EG020A-F: Cobalt 96.70.2 mg/L 13070

7440-50-8EG020A-F: Copper # Not Determined0.2 mg/L 13070

7439-92-1EG020A-F: Lead 83.40.2 mg/L 13070

7439-96-5EG020A-F: Manganese 92.70.2 mg/L 13070

7440-02-0EG020A-F: Nickel 87.50.2 mg/L 13070

7440-62-2EG020A-F: Vanadium 73.70.2 mg/L 13070

7440-66-6EG020A-F: Zinc 84.00.2 mg/L 13070

EG035F: Dissolved Mercury by FIMS (QCLot: 2061098)

AnonymousES1125647-002 7439-97-6EG035F: Mercury 93.60.0100 mg/L 13070

EG051G: Ferrous Iron by Discrete Analyser (QCLot: 2046352)

AnonymousEP1107932-001 ----EG051G: Ferrous Iron 99.42.5 mg/L 13070

EK026G: Total Cyanide By Discrete Analyser (QCLot: 2058366)

AnonymousEP1107982-001 57-12-5EK026G: Total Cyanide 88.550 mg/L 13070

EK027: Thiocyanate (QCLot: 2049125)

DETOX LIQUOREP1107934-001 463-56-9EK027: Thiocyanate 104500 mg/L 13070

EK055G: Ammonia as N by Discrete Analyser (QCLot: 2068012)

DETOX LIQUOREP1107934-001 7664-41-7EK055G: Ammonia as N # Not Determined1.00 mg/L 13070

EK057G: Nitrite as N by Discrete Analyser (QCLot: 2046743)

AnonymousEP1107929-010 ----EK057G: Nitrite as N 86.10.6 mg/L 13070

EK059G: Nitrite plus Nitrate as N (NOx) by Discrete Analyser (QCLot: 2068011)

DETOX LIQUOREP1107934-001 ----EK059G: Nitrite + Nitrate as N # Not Determined0.6 mg/L 13070

True

INTERPRETIVE QUALITY CONTROL REPORT

Work Order : EP1107934 Page : 1 of 12

:: LaboratoryClient Environmental Division PerthAMMTEC LTD: :ContactContact MR WAYNE HARDING Scott James




:: E-mailE-mail [email protected] [email protected]:: TelephoneTelephone +61 08 9344 2416 +61-8-9209 7655:: FacsimileFacsimile +61 08 9345 4688 +61-8-9209 7600

:Project Tetratech QC Level : NEPM 1999 Schedule B(3) and ALS QCS3 requirementSite : ----


----:Sampler Issue Date : 02-DEC-2011:Order number 098212

No. of samples received : 2Quote number : EP/570/11 No. of samples analysed : 2

This report supersedes any previous report(s) with this reference. Results apply to the sample(s) as submitted. All pages of this report have been checked and approved for release.

This Interpretive Quality Control Report contains the following information:

l Analysis Holding Time Compliance

l Quality Control Parameter Frequency Compliance

l Brief Method Summaries

l Summary of Outliers




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Analysis Holding Time ComplianceThe following report summarises extraction / preparation and analysis times and compares with recommended holding times. Dates reported represent first date of extraction or analysis and precludes subsequent

dilutions and reruns. Information is also provided re the sample container (preservative) from which the analysis aliquot was taken. Elapsed period to analysis represents number of days from sampling where no

extraction / digestion is involved or period from extraction / digestion where this is present. For composite samples, sampling date is assumed to be that of the oldest sample contributing to the composite. Sample date

for laboratory produced leachates is assumed as the completion date of the leaching process. Outliers for holding time are based on USEPA SW 846, APHA, AS and NEPM (1999). A listing of breaches is provided in the

Summary of Outliers.

Holding times for leachate methods (excluding elutriates) vary according to the analytes being determined on the resulting solution. For non -volatile analytes, the holding time compliance assessment compares the leach

date with the shortest analyte holding time for the equivalent soil method. These soil holding times are: Organics (14 days); Mercury (28 days) & other metals (180 days). A recorded breach therefore does not guarantee

a breach for all non-volatile parameters.

Matrix: SOIL Evaluation: û = Holding time breach ; ü = Within holding time.

AnalysisExtraction / PreparationSample DateMethod

EvaluationDue for analysisDate analysedEvaluationDue for extractionDate extractedContainer / Client Sample ID(s)

EA011: Net Acid Generation

80* dried soil

13-MAY-201214-NOV-2012DETOX RESIDUE 21-NOV-201115-NOV-201115-NOV-2011 ü üEA023 : TOS-ASS

80* dried soil

19-FEB-201214-NOV-2012DETOX RESIDUE 22-NOV-201121-NOV-201115-NOV-2011 ü üEA029-A: pH Measurements

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 22-NOV-201115-NOV-201115-NOV-2011 ü üEA029-B: Acidity Trail

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 22-NOV-201115-NOV-201115-NOV-2011 ü üEA029-C: Sulfur Trail

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 22-NOV-201115-NOV-201115-NOV-2011 ü üEA029-D: Calcium Values

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 22-NOV-201115-NOV-201115-NOV-2011 ü üEA029-E: Magnesium Values

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 22-NOV-201115-NOV-201115-NOV-2011 ü üEA029-F: Excess Acid Neutralising Capacity

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 22-NOV-201115-NOV-201115-NOV-2011 ü üEA029-G: Retained Acidity

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 22-NOV-201115-NOV-201115-NOV-2011 ü üEA029-H: Acid Base Accounting

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 22-NOV-201115-NOV-201115-NOV-2011 ü üEA033-A: Actual Acidity

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 29-NOV-201115-NOV-201115-NOV-2011 ü ü

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Matrix: SOIL Evaluation: û = Holding time breach ; ü = Within holding time.



EA033-B: Potential Acidity

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 29-NOV-201115-NOV-201115-NOV-2011 ü üEA033-C: Acid Neutralising Capacity

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 29-NOV-201115-NOV-201115-NOV-2011 ü üEA033-D: Retained Acidity

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 29-NOV-201115-NOV-201115-NOV-2011 ü üEA033-E: Acid Base Accounting

80* dried soil

13-FEB-201214-NOV-2012DETOX RESIDUE 29-NOV-201115-NOV-201115-NOV-2011 ü üEA055: Moisture Content

Calico Bag

29-NOV-2011----DETOX RESIDUE 21-NOV-2011----15-NOV-2011 ---- üED040T : Total Sulfate by ICPAES

Calico Bag

21-DEC-201122-NOV-2011DETOX RESIDUE 23-NOV-201123-NOV-201115-NOV-2011 û üED042T: Total Sulfur by LECO

80* dried soil

13-MAY-201213-MAY-2012DETOX RESIDUE 21-NOV-201121-NOV-201115-NOV-2011 ü üMatrix: WATER Evaluation: û = Holding time breach ; ü = Within holding time.




Clear Plastic Bottle - Natural

15-NOV-201115-NOV-2011DETOX LIQUOR 16-NOV-2011---15-NOV-2011 ---- ûEA010P: Conductivity by PC Titrator


13-DEC-201113-DEC-2011DETOX LIQUOR 16-NOV-2011---15-NOV-2011 ---- üED037P: Alkalinity by PC Titrator


29-NOV-201129-NOV-2011DETOX LIQUOR 16-NOV-2011---15-NOV-2011 ---- üED038A: Acidity


29-NOV-2011----DETOX LIQUOR 21-NOV-2011----15-NOV-2011 ---- üED041G: Sulfate (Turbidimetric) as SO4 2- by DA


13-DEC-201113-DEC-2011DETOX LIQUOR 16-NOV-2011---15-NOV-2011 ---- üED045G: Chloride Discrete analyser


13-DEC-201113-DEC-2011DETOX LIQUOR 16-NOV-2011---15-NOV-2011 ---- ü

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Matrix: WATER Evaluation: û = Holding time breach ; ü = Within holding time.



EG020F: Dissolved Metals by ICP-MS

Clear Plastic Bottle - Filtered; Lab-acidified

13-MAY-201213-MAY-2012DETOX LIQUOR 28-NOV-2011---15-NOV-2011 ---- üEG035F: Dissolved Mercury by FIMS

Clear Plastic Bottle - Filtered; Lab-acidified

13-DEC-201113-DEC-2011DETOX LIQUOR 29-NOV-2011---15-NOV-2011 ---- üEG051G: Ferrous Iron by Discrete Analyser

Clear Plastic Bottle - HCl - Unfiltered

16-NOV-2011----DETOX LIQUOR 16-NOV-2011----15-NOV-2011 ---- üEK025G: Free cyanide by Discrete Analyser

White Plastic Bottle-NaOH

29-NOV-201129-NOV-2011DETOX LIQUOR 24-NOV-201124-NOV-201115-NOV-2011 ü üEK026G: Total Cyanide By Discrete Analyser

White Plastic Bottle-NaOH

29-NOV-201129-NOV-2011DETOX LIQUOR 24-NOV-201124-NOV-201115-NOV-2011 ü üEK027: Thiocyanate

Clear Plastic Bottle - Nitric Acid; Unfiltered

13-MAY-2012----DETOX LIQUOR 18-NOV-2011----15-NOV-2011 ---- üEK055G: Ammonia as N by Discrete Analyser

Clear Plastic Bottle - Sulfuric Acid

13-DEC-201113-DEC-2011DETOX LIQUOR 30-NOV-2011---15-NOV-2011 ---- üEK057G: Nitrite as N by Discrete Analyser


17-NOV-201117-NOV-2011DETOX LIQUOR 16-NOV-2011---15-NOV-2011 ---- üEK059G: Nitrite plus Nitrate as N (NOx) by Discrete Analyser

Clear Plastic Bottle - Sulfuric Acid

13-DEC-201113-DEC-2011DETOX LIQUOR 30-NOV-2011---15-NOV-2011 ---- ü

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Quality Control Parameter Frequency ComplianceThe following report summarises the frequency of laboratory QC samples analysed within the analytical lot(s) in which the submitted sample(s) was(where) processed. Actual rate should be greater than or equal to the

expected rate. A listing of breaches is provided in the Summary of Outliers.

Matrix: SOIL Evaluation: û = Quality Control frequency not within specification ; ü = Quality Control frequency within specification.

Quality Control SpecificationQuality Control Sample Type

ExpectedQC Regular Actual

Rate (%)Quality Control Sample Type CountEvaluationAnalytical Methods Method

Laboratory Duplicates (DUP)

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 100.0 10.01 1 üChromium Suite for Acid Sulphate Soils EA033

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 100.0 10.01 1 üHCl Extractable S EA023SHCl

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 10.0 10.02 20 üMoisture Content EA055-103

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 100.0 10.01 1 üNet Acid Generation EA011

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 100.0 10.01 1 üSulfate as SO4 2- Total ED040T

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 100.0 10.01 1 üSulfur - Total as S (LECO) ED042T

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 100.0 10.01 1 üSuspension Peroxide Oxidation-Combined Acidity and

Sulphate

EA029

Laboratory Control Samples (LCS)


NEPM 1999 Schedule B(3) and ALS QCS3 requirement 100.0 5.01 1 üNet Acid Generation EA011



Sulphate

EA029

Method Blanks (MB)


NEPM 1999 Schedule B(3) and ALS QCS3 requirement 100.0 5.01 1 üHCl Extractable S EA023SHCl

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 100.0 5.01 1 üSulfate as SO4 2- Total ED040T



Sulphate

EA029

Matrix: WATER Evaluation: û = Quality Control frequency not within specification ; ü = Quality Control frequency within specification.





NEPM 1999 Schedule B(3) and ALS QCS3 requirement 10.0 10.02 20 üAcidity as Calcium Carbonate ED038

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 33.3 10.01 3 üAlkalinity by PC Titrator ED037-P

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 16.7 10.02 12 üAmmonia as N by Discrete analyser EK055G

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 5.0 10.01 20 ûChloride by Discrete Analyser ED045G

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 11.1 10.02 18 üConductivity by PC Titrator EA010-P

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 18.2 10.02 11 üDissolved Mercury by FIMS EG035F

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 11.1 10.02 18 üDissolved Metals by ICP-MS - Suite A EG020A-F

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 11.1 10.02 18 üDissolved Metals by ICP-MS - Suite B EG020B-F

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 11.1 10.02 18 üDissolved Metals by ICP-MS - Suite D EG020D-F

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 20.0 10.02 10 üFerrous Iron by Discrete Analyser EG051G

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 100.0 10.01 1 üFree CN by Discrete Analyser EK025G

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 7.1 10.01 14 ûNitrite and Nitrate as N (NOx) by Discrete Analyser EK059G

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 5.0 10.01 20 ûNitrite as N by Discrete Analyser EK057G

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Laboratory Duplicates (DUP) - Continued

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 6.3 10.01 16 ûpH by PC Titrator EA005-P

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 10.0 10.02 20 üSulfate (Turbidimetric) as SO4 2- by Discrete Analyser ED041G

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 100.0 10.01 1 üThiocyanate EK027

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 33.3 10.01 3 üTotal Cyanide By Discrete Analyser EK026G

Laboratory Control Samples (LCS)

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 5.0 5.01 20 üAcidity as Calcium Carbonate ED038



NEPM 1999 Schedule B(3) and ALS QCS3 requirement 10.0 10.02 20 üChloride by Discrete Analyser ED045G







NEPM 1999 Schedule B(3) and ALS QCS3 requirement 7.1 5.01 14 üNitrite and Nitrate as N (NOx) by Discrete Analyser EK059G

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 5.0 5.01 20 üNitrite as N by Discrete Analyser EK057G

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 12.5 10.02 16 üpH by PC Titrator EA005-P




Method Blanks (MB)



NEPM 1999 Schedule B(3) and ALS QCS3 requirement 5.0 5.01 20 üChloride by Discrete Analyser ED045G





NEPM 1999 Schedule B(3) and ALS QCS3 requirement 5.6 5.01 18 üDissolved Metals by ICP-MS - Suite D EG020D-F



NEPM 1999 Schedule B(3) and ALS QCS3 requirement 7.1 5.01 14 üNitrite and Nitrate as N (NOx) by Discrete Analyser EK059G

NEPM 1999 Schedule B(3) and ALS QCS3 requirement 5.0 5.01 20 üNitrite as N by Discrete Analyser EK057G




Matrix Spikes (MS)

ALS QCS3 requirement 8.3 5.01 12 üAmmonia as N by Discrete analyser EK055G

ALS QCS3 requirement 5.0 5.01 20 üChloride by Discrete Analyser ED045G

ALS QCS3 requirement 9.1 5.01 11 üDissolved Mercury by FIMS EG035F

ALS QCS3 requirement 5.6 5.01 18 üDissolved Metals by ICP-MS - Suite A EG020A-F

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Matrix Spikes (MS) - Continued

ALS QCS3 requirement 10.0 5.01 10 üFerrous Iron by Discrete Analyser EG051G

ALS QCS3 requirement 7.1 5.01 14 üNitrite and Nitrate as N (NOx) by Discrete Analyser EK059G

ALS QCS3 requirement 5.0 5.01 20 üNitrite as N by Discrete Analyser EK057G

ALS QCS3 requirement 5.0 5.01 20 üSulfate (Turbidimetric) as SO4 2- by Discrete Analyser ED041G

ALS QCS3 requirement 100.0 5.01 1 üThiocyanate EK027

ALS QCS3 requirement 33.3 5.01 3 üTotal Cyanide By Discrete Analyser EK026G

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Brief Method SummariesThe analytical procedures used by the Environmental Division have been developed from established internationally recognized procedures such as those published by the US EPA, APHA, AS and NEPM. In house

developed procedures are employed in the absence of documented standards or by client request. The following report provides brief descriptions of the analytical procedures employed for results reported in the

Certificate of Analysis. Sources from which ALS methods have been developed are provided within the Method Descriptions.

Analytical Methods Method DescriptionsMatrixMethod

Miller (1998) Titremetric procedure determines net acidity in a soil following peroxide oxidation. Titrations to both

pH 4.5 and pH 7 are reported.

Net Acid Generation EA011 SOIL

Ahern et al (1997)- Cations are determined in 1:40 suspension of 4 M HCL.HCl Extractable S EA023SHCl SOIL

In-house. Dried and pulverised sample is combusted in a LECO furnace at 1350C in the presence of strong

oxidants / catalysts. The evolved S (as SO2) is measured by infra-red detector. This method is compliant with

NEPM (1999) Schedule B(3)

S Total by Leco EA023STOT SOIL

Ahern et al (1998b)- a measure of the oxidisable sulfur obtained by the indirect method of subtracting the 4 M HCl

extractable sulfur from total S determined by LECO.

Total Oxidisable Sulfur (AAS) EA023TOS-ASS SOIL

Ahern et al 2004 - a suspension peroxide oxidation method following the 'sulfur trail' by determining the level of 1M

KCL extractable sulfur and the sulfur level after oxidation of soil sulphides. The 'acidity trail' is followed by

measurement of TAA, TPA and TSA. Liming Rate is based on results for samples as submitted and incorporates

a minimum safety factor of 1.5.

Suspension Peroxide

Oxidation-Combined Acidity and

Sulphate

EA029 SOIL

Ahern et al 2004. This method covers the determination of Chromium Reducible Sulfur (SCR); pHKCl; titratable

actual acidity (TAA); acid neutralising capacity by back titration (ANC); and net acid soluble sulfur (SNAS) which

incorporates peroxide sulfur. It applies to soils and sediments (including sands) derived from coastal regions.

Liming Rate is based on results for samples as submitted and incorporates a minimum safety factor of 1.5.

Chromium Suite for Acid Sulphate Soils EA033 SOIL

A gravimetric procedure based on weight loss over a 12 hour drying period at 103-105 degrees C. This method is

compliant with NEPM (2010 Draft) Schedule B(3) Section 7.1 and Table 1 (14 day holding time).

Moisture Content EA055-103 SOIL

In-house. Total Sulfate is determined off a HCl digestion by ICPAES as S , and reported as SO4Sulfate as SO4 2- Total ED040T SOIL

In-house. Dried and pulverised sample is combusted in a LECO furnace at 1350C in the presence of strong

oxidants / catalysts. The evolved S (as SO2) is measured by infra-red detector

Sulfur - Total as S (LECO) ED042T SOIL

In-house. Sulfide in a soil is determined as the difference between Total Sulfur (Leco) and Sulfate.Sulfide as S EK085 SOIL

Miscellaneous Subcontracted Analysis conducted by Subcontracting LaboratoryMiscellaneous Subcontracted Analysis MIS-SOL SOIL

APHA 21st ed. 4500 H+ B. This procedure determines pH of water samples by automated ISE. This method is

compliant with NEPM (1999) Schedule B(3) (Appdx. 2)

pH by PC Titrator EA005-P WATER

APHA 21st ed., 2510 B This procedure determines conductivity by automated ISE. This method is compliant with

NEPM (1999) Schedule B(3) (Appdx. 2)

Conductivity by PC Titrator EA010-P WATER

APHA 21st ed., 2320 B This procedure determines alkalinity by automated measurement (e.g. PC Titrate) using

pH 4.5 for indicating the total alkalinity end-point. This method is compliant with NEPM (1999) Schedule B(3)

(Appdx. 2)

Alkalinity by PC Titrator ED037-P WATER

APHA 21st ed., 2310 B Acidity is determined by titration with a standardised alkali to an end-point pH of 8.3. This

method is compliant with NEPM (1999) Schedule B(3) (Appdx. 2)

Acidity as Calcium Carbonate ED038 WATER

APHA 21st ed., 4500-SO4 Sulfate ions are converted to a barium sulfate suspension in an acetic acid medium

with barium chloride. Light absorbance of the BaSO4 suspension is measured by a photometer and the SO4-2

concentration is determined by comparison of the reading with a standard curve. This method is compliant with

NEPM (1999) Schedule B(3) (Appdx. 2)

Sulfate (Turbidimetric) as SO4 2- by

Discrete Analyser

ED041G WATER

APHA 21st ed., 4500 Cl - G.The thiocyanate ion is liberated from mercuric thiocyanate through sequestration of

mercury by the chloride ion to form non-ionised mercuric chloride.in the presence of ferric ions the librated

thiocynate forms highly-coloured ferric thiocynate which is measured at 480 nm APHA 21st edition seal method 2

017-1-L april 2003

Chloride by Discrete Analyser ED045G WATER

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Analytical Methods Method DescriptionsMatrixMethod

(APHA 21st ed., 3125; USEPA SW846 - 6020, ALS QWI-EN/EG020): Samples are 0.45 um filtered prior to

analysis. The ICPMS technique utilizes a highly efficient argon plasma to ionize selected elements. Ions are then

passed into a high vacuum mass spectrometer, which separates the analytes based on their distinct mass to

charge ratios prior to their measurement by a discrete dynode ion detector.

Dissolved Metals by ICP-MS - Suite A EG020A-F WATER





Dissolved Metals by ICP-MS - Suite B EG020B-F WATER





Dissolved Metals by ICP-MS - Suite D EG020D-F WATER

AS 3550, APHA 21st ed. 3112 Hg - B (Flow-injection (SnCl2)(Cold Vapour generation) AAS) Samples are 0.45 um

filtered prior to analysis. FIM-AAS is an automated flameless atomic absorption technique. A bromate/bromide

reagent is used to oxidise any organic mercury compounds in the filtered sample. The ionic mercury is reduced

online to atomic mercury vapour by SnCl2 which is then purged into a heated quartz cell. Quantification is by

comparing absorbance against a calibration curve. This method is compliant with NEPM (1999) Schedule B(3)

(Appdx. 2)

Dissolved Mercury by FIMS EG035F WATER

APHA 21st ed., 3500 Fe-B. A colorimetric determination based on the reaction between phenanthroline and

ferrous iron at pH 3.2-3.3 to form an orange-red complex that is measured against a five-point calibration curve.

This method is compliant with NEPM (1999) Schedule B(3) (Appdx. 2)

Ferrous Iron by Discrete Analyser EG051G WATER

APHA 21st ed., 3500 Fe-B. The 0.45um filtered Ferric Iron is determined as the difference between Filtered Iron

and Filtered Ferrous Iron quantify by ICPMS and Discrete Analyser.

Ferric Iron - Dissolved EG053FG-MS WATER

APHA 21st ed., 4500-CN-C&N Free Cyanide is determined on samples after distillation using a pyridine- barbituric

acid colouring reagent followed with an Discrete Analyser finish. This method is compliant with NEPM (1999)

Schedule B(3) (Appdx. 2)

Free CN by Discrete Analyser EK025G WATER

APHA 21st ed., 4500-CN-C & N Total Cyanide is determined from aqueous solutions after distillation with

sulphuric acid. The resultant distillate is then captured in a caustic absorber solution followed by Discrete Analyser.

This method is compliant with NEPM (1999) Schedule B(3) (Appdx. 2)

Total Cyanide By Discrete Analyser EK026G WATER

APHA 21st ed., 4500 CN- M. This method is compliant with NEPM (1999) Schedule B(3) (Appdx. 2)Thiocyanate EK027 WATER

APHA 21st ed., 4500-NH3 G Ammonia is determined by direct colorimetry by Discrete Analyser. This method is


Ammonia as N by Discrete analyser EK055G WATER

APHA 21st ed., 4500-NO2- B. Nitrite is determined by direct colourimetry by Discrete Analyser. This method is


Nitrite as N by Discrete Analyser EK057G WATER

APHA 21st ed., 4500-NO3- F. Nitrate is reduced to nitrite by way of a cadmium reduction column followed by

quantification by Discrete Analyser. Nitrite is determined seperately by direct colourimetry and result for Nitrate

calculated as the difference between the two results. This method is compliant with NEPM (1999) Schedule B(3)

(Appdx. 2)

Nitrate as N by Discrete Analyser EK058G WATER

APHA 21st ed., 4500-NO3- F. Combined oxidised Nitrogen (NO2+NO3) is determined by Cadmium Reduction and

direct colourimetry by Discrete Analyser. This method is compliant with NEPM (1999) Schedule B(3) (Appdx. 2)

Nitrite and Nitrate as N (NOx) by Discrete

Analyser

EK059G WATER

Preparation Methods Method DescriptionsMatrixMethod

In houseDrying at 85 degrees, bagging and

labelling (ASS)

EN020PR SOIL

1g of soil is digested in 30 ml of 30% HCl and the resultant digest bulked and filtered for analysis by ICP.HCl Digest EN24 SOIL

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Preparation Methods Method DescriptionsMatrixMethod

APHA 21st ed., 4500 CN- C&N. The sample is distilled at natural pH. The CN is trapped in a caustic solution, and

quanitified by colourimetry on FIA. This method is compliant with NEPM (1999) Schedule B(3) (Appdx. 2)

Free Cyanide EK025-PR WATER

APHA 21st ed., 4500 CN- C&N. The sample is distilled with H2SO4 releasing all bound cyanides as HCN. The CN

is trapped in a caustic solution, and quanitified by colourimetry on FIA. This method is compliant with NEPM (1999)

Schedule B(3) (Appdx. 2)

Total Cyanide EK026-PR WATER

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Summary of Outliers

Outliers : Quality Control Samples

The following report highlights outliers flagged in the Quality Control (QC) Report. Surrogate recovery limits are static and based on USEPA SW846 or ALS-QWI/EN/38 (in the absence of specific USEPA limits). This

report displays QC Outliers (breaches) only.

Duplicates, Method Blanks, Laboratory Control Samples and Matrix Spikes

Matrix: WATER

Compound Group Name CommentLimitsDataAnalyteClient Sample IDLaboratory Sample ID CAS Number

Laboratory Control Spike (LCS) Recoveries

2438606-009 7429-90-5Aluminium---- Recovery greater than upper control limit92-112%121 %EG020F: Dissolved Metals by ICP-MS

2438606-009 7439-92-1Lead---- Recovery less than lower control limit90-110%89.1 %EG020F: Dissolved Metals by ICP-MS

2438606-009 7440-62-2Vanadium---- Recovery less than lower control limit91-109%79.7 %EG020F: Dissolved Metals by ICP-MS

2438606-009 22541-49-7Tellurium---- Recovery less than lower control limit88-106%87.6 %EG020F: Dissolved Metals by ICP-MS

2438606-009 7440-32-6Titanium---- Recovery less than lower control limit88-112%87.6 %EG020F: Dissolved Metals by ICP-MS

Matrix Spike (MS) Recoveries

EP1107934-001 7440-50-8CopperDETOX LIQUOR MS recovery not determined, background

level greater than or equal to 4x spike

level.

----Not

DeterminedEG020F: Dissolved Metals by ICP-MS

EP1107934-001 7664-41-7Ammonia as NDETOX LIQUOR MS recovery not determined, background


level.

----Not

DeterminedEK055G: Ammonia as N by Discrete Analyser

Nitrite + Nitrate as NEP1107934-001 ----DETOX LIQUOR MS recovery not determined, background


level.

----Not

DeterminedEK059G: Nitrite plus Nitrate as N (NOx) by Discrete Analyser

l For all matrices, no Method Blank value outliers occur.

l For all matrices, no Duplicate outliers occur.

Regular Sample Surrogates

l For all regular sample matrices, no surrogate recovery outliers occur.

Outliers : Analysis Holding Time Compliance

This report displays Holding Time breaches only. Only the respective Extraction / Preparation and/or Analysis component is/are displayed.

Matrix: SOIL

AnalysisExtraction / Preparation

Date analysedDate extractedContainer / Client Sample ID(s) Days

overdue

Days

overdue

Due for extraction Due for analysis

Method

ED040T : Total Sulfate by ICPAES

Calico Bag

----22-NOV-2011DETOX RESIDUE ----23-NOV-2011 1 ----

Matrix: WATER

12 of 12:Page

Work Order :

:Client

EP1107934

AMMTEC LTD

Tetratech:Project

Matrix: WATER

AnalysisExtraction / Preparation

Date analysedDate extractedContainer / Client Sample ID(s) Days

overdue

Days

overdue

Due for extraction Due for analysis

Method



15-NOV-2011----DETOX LIQUOR 16-NOV-2011---- ---- 1

Outliers : Frequency of Quality Control Samples

The following report highlights breaches in the Frequency of Quality Control Samples.

Matrix: WATER


Method ExpectedQC Regular Actual

Rate (%)Quality Control Sample Type Count


NEPM 1999 Schedule B(3) and ALS QCS3 requirementChloride by Discrete Analyser 5.0 10.01 20

NEPM 1999 Schedule B(3) and ALS QCS3 requirementNitrite and Nitrate as N (NOx) by Discrete Analyser 7.1 10.01 14

NEPM 1999 Schedule B(3) and ALS QCS3 requirementNitrite as N by Discrete Analyser 5.0 10.01 20

NEPM 1999 Schedule B(3) and ALS QCS3 requirementpH by PC Titrator 6.3 10.01 16

SAMPLE RECEIPT NOTIFICATION (SRN)Comprehensive Report

Work Order : EP1107934

:: LaboratoryClient Environmental Division PerthAMMTEC LTD: :ContactContact MR WAYNE HARDING Scott James


BALCATTA WESTERN AUSTRALIA

2416


:: E-mailE-mail [email protected] [email protected]:: TelephoneTelephone +61 08 9344 2416 +61-8-9209 7655:: FacsimileFacsimile +61 08 9345 4688 +61-8-9209 7600

::Project Tetratech Page 1 of 3:Order number 098212

::C-O-C number ---- Quote number EP2011AMMTEC0006 (EP/570/11)Site : ----Sampler : :QC Level---- NEPM 1999 Schedule B(3) and ALS

QCS3 requirement

DatesDate Samples Received : 15-NOV-2011 Issue Date : 15-NOV-2011 19:36

Scheduled Reporting Date: 01-DEC-2011:Client Requested Due Date 01-DEC-2011

Delivery DetailsMode of Delivery Temperature: :Carrier 17 - Ice bricks presentNo. of coolers/boxes No. of samples received: :1 Med Esky 2Security Seal No. of samples analysed: :Intact. 2

General Comments

This report contains the following information:l

- Sample Container(s)/Preservation Non-Compliances

- Summary of Sample(s) and Requested Analysis

- Proactive Holding Time Report

- Requested Deliverables

l Sample containers do not comply to pretreatment / preservation standards (AS, APHA, USEPA). Please refer to the Sample

Container(s)/Preservation Non-Compliance Log at the end of this report for details.

Please see scanned COC for sample discrepencies: extra samples , samples not received etc.l

l Sample containers do not comply to pretreatment / preservation standards (AS, APHA, USEPA).

Please refer to the Sample Container(s)/Preservation Non-Compliance Log at the end of this

report for details.

pH analysis should be conducted within 6 hours of sampling.l

Analytical work for this work order will be conducted at ALS Environmental Perth.l

Please direct any turnaround / technical queries to the laboratory contact designated above.l

Please direct any queries related to sample condition / numbering / breakages to Sample Receipt ([email protected])l

Sample Disposal - Aqueous (14 days), Solid (90 days) from date of completion of Work Order.l




15-NOV-2011 19:36:Issue Date

2 of 3:Page

Work Order :

:Client

EP1107934

AMMTEC LTD

Sample Container(s)/Preservation Non-Compliances

All comparisons are made against pretreatment/preservation AS, APHA, USEPA standards.

MethodSample Container Received Preferred Sample Container for AnalysisClient sample ID

ED043 : Sulfur - Total Oxidised as SO4 2-

DETOX RESIDUE - Calico Bag - Soil Glass Jar - Unpreserved

EG051G : Ferrous Iron by Discrete Analyser

DETOX LIQUOR - Clear Plastic Bottle - HCl -

Unfiltered

- Clear Plastic Bottle - HCl - Filtered

Summary of Sample(s) and Requested Analysis

Some items described below may be part of a laboratory

process neccessary for the execution of client requested

tasks. Packages may contain additional analyses, such as

the determination of moisture content and preparation

tasks, that are included in the package.

If no sampling time is provided, the sampling time will

default to 15:00 on the date of sampling. If no sampling

date is provided, the sampling date will be assumed by the

laboratory for processing purposes and will be shown

bracketed without a time component.

SO

IL -

EA

01

1

Ne

t A

cid

Ge

ne

ratio

n (

NA

G)

SO

IL -

EA

02

9-W

A

WA

- S

PO

CA

S

SO

IL -

EA

03

3-W

A

WA

- C

hro

miu

m S

uite

fo

r A

cid

Su

lph

ate

So

ils

SO

IL -

EA

05

5-1

03

Mo

istu

re C

on

ten

t

SO

IL -

ED

04

3

Su

lfur

- T

ota

l Oxi

dis

ed

Su

lfur

as S

O4

2-

SO

IL -

EK

08

5

Su

lfid

e a

s S

SO

IL -

MIS

-SO

L (

Su

bco

ntr

acte

d)

Mis

cella

ne

ou

s S

ub

con

tra

cte

d A

na

lysi

s

(So

lid)

EP1107934-002 [ 15-NOV-2011 ] DETOX RESIDUE ü ü ü ü ü ü ü

Matrix: SOIL

Client sample IDLaboratory sample

ID

Client sampling

date / time

WA

TE

R -

EA

00

5P

pH

(P

C)

WA

TE

R -

EA

01

0P

Co

nd

uct

ivity

(P

C)

WA

TE

R -

ED

03

7P

To

tal A

lka

linity

as

Ca

CO

3 (

PC

)

WA

TE

R -

ED

03

8 C

aC

O3

Aci

dity

as

Ca

CO

3 o

nly

WA

TE

R -

ED

04

1G

Su

lfate

(T

urb

idim

etr

ic)

as

SO

4 2

by

Dis

cre

te A

na

lyse

r

WA

TE

R -

ED

04

5G

Ch

lorid

e b

y D

iscr

ete

An

aly

ser

WA

TE

R -

EG

03

5F

Dis

solv

ed

Me

rcu

ry b

y F

IMS

WA

TE

R -

EG

05

3F

G-M

S

Dis

solv

ed

Fe

rric

Iro

n b

y IC

PM

S/D

A

EP1107934-001 [ 15-NOV-2011 ] DETOX LIQUOR ü ü ü ü ü ü ü ü

Matrix: WATER


ID

Client sampling

date / time

15-NOV-2011 19:36:Issue Date

3 of 3:Page

Work Order :

:Client

EP1107934

AMMTEC LTD

WA

TE

R -

EK

02

5G

Fre

e C

N B

y D

iscre

te A

na

lyse

r

WA

TE

R -

EK

02

6G

To

tal C

yan

ide

by D

iscr

ete

An

aly

ser

WA

TE

R -

EK

02

7

Th

iocya

na

te

WA

TE

R -

EK

05

5G

Am

mo

nia

as N

By D

iscre

te A

na

lyse

r

WA

TE

R -

ME

-02

ICP

/MS

Dis

so

lve

d M

eta

ls -

Fu

ll S

can

WA

TE

R -

NT

-04

Nitrite

an

d N

itra

te

EP1107934-001 [ 15-NOV-2011 ] DETOX LIQUOR ü ü ü ü ü ü

Matrix: WATER


ID

Client sampling

date / time

Proactive Holding Time Report

Sample(s) have been received within the recommended holding times for the requested analysis.

Requested Deliverables

MR WAYNE HARDING

- *AU Certificate of Analysis - NATA ( COA ) Email [email protected] *AU Interpretive QC Report - DEFAULT (Anon QCI Rep) ( QCI ) Email [email protected] *AU QC Report - DEFAULT (Anon QC Rep) - NATA ( QC ) Email [email protected] A4 - AU Sample Receipt Notification - Environmental HT ( SRN ) Email [email protected] A4 - AU Tax Invoice ( INV ) Email [email protected] Attachment - Report ( SUBCO ) Email [email protected] Chain of Custody (CoC) ( COC ) Email [email protected] EDI Format - ENMRG ( ENMRG ) Email [email protected] EDI Format - ESDAT ( ESDAT ) Email [email protected] EDI Format - XTab ( XTAB ) Email [email protected]

Cyanide Destruction Testwork

conducted on

Testwork Products from the Mt Todd Gold Project

for

Vista Gold Corporation

Report No. A13575

October 2011

The results contained in this report relate only to the sample(s) submitted for testing. ALS Ammtec accepts no responsibility for the representativeness of the sample(s) submitted.

Report No. A13575 Detox

TABLE OF CONTENTS PAGE NO. SUMMARY (i) 1. INTRODUCTION 1

2. SAMPLE RECEIPT AND PREPARATION 1

2.1 Sample Receipt 1

2.2 Sample Analysis 1

3. TESTWORK METHODOLOGY 2

3.1 SO2/Air Testwork 2

3.1.1 The SO2/Air Process 2

3.1.2 Stoichiometric Requirements 3

3.1.3 Cyanide Detoxification Testing 3

3.1.4 Reaction Vessel and Equipment Arrangement 3

3.1.5 Operation 4

3.1.6 Cyanide Analysis 4

4. TESTWORK RESULTS 5

4.1 Summary of Results for Cyanide Detoxification Testwork 5

4.2 SO2/Air Testwork 6

4.2.1 Results 6

4.2.2 Comments 7

APPENDICES Appendix I Leach and Optimum Detoxification Effluent Characterisation Results Appendix II SO

2/Air Detoxification Testwork Results

Appendix III Chem Centre of WA Cyanide Speciation Reports


LIST OF TABLES PAGE NO. Table 1.1: Summary of Detoxification Results ........................................................1

Table 1.2: SO2/Air Cyanide Detoxification Results...................................................2

Table 4.1: Summary of Detoxification Results ........................................................5

Table 4.2: SO2/Air Cyanide Detoxification Results...................................................6

Page i of iii Report No. A13575 Detox

SUMMARY

• Summary of Results Two samples of cyanidation leach tailings from Vista Gold Corporation’s Mt Todd Gold Project were received on 10th October 2011.

• Summary of Results for Cyanide Detoxification Testwork The key indicators for the detoxification testwork are presented in TABLE 1.1.

TABLE 1.1: SUMMARY OF DETOXIFICATION RESULTS

Test No. Cu

(mg/L) Fe

(mg/L) Ni

(mg/L) Zn

(mg/L) CNP

(mg/L) CNTOTAL

(mg/L)

WH4270

Feed 34.10 11.40 0.65 5.30 182 213

D1 23.15 0.45 0.78 0.02 39.0 40.2

D2 20.40 0.75 0.10 0.58 39.5 41.6

D3 16.95 0.35 0.10 0.28 27.2 28.1

D4 1.55 1.70 0.25 0.04 0.60 5.35

D5 0.21 6.10 0.05 0.02 2.42 19.5

D6 2.10 2.25 0.38 0.04 2.00 8.29

WH4271

Feed 40.40 5.90 0.60 7.42 214 230

D7 3.54 0.35 0.05 0.47 18.8 19.8

D8 1.78 0.15 0.05 0.08 0.90 1.32

D9 1.56 0.10 0.05 0.05 7.08 7.36

D10 1.57 0.65 0.05 0.42 1.39 3.20

D11 1.24 0.10 0.05 0.03 0.83 1.11

D12 1.34 0.20 0.10 0.02 0.41 0.97

Page ii of iii Report No. A13575 Detox

• SO2/Air Cyanide Detoxification Testwork Testwork on the leach effluent using the SO

2/air process for cyanide detoxification

produced the results outlined in TABLE 1.2.

TABLE 1.2: SO2/AIR CYANIDE DETOXIFICATION RESULTS

Test No.

Test Conditions Solution Assays

pH Retention

Time (minutes)

Reagents Used Feed Effluent CNP

(mg/L)

Treated Effluent CNP

(mg/L)

Treated Effluent CNTOT

(mg/L) SO2

(g/g CNWAD) Cu2+

(mg/L) Lime

(g/g SO2)

WH4270

D1 8.72 60.14 2.67 26 0.50 182 39.0 40.2

D2 8.51 62.30 3.35 27 0.83 182 39.5 41.6

D3 8.49 54.34 3.49 24 2.36 182 27.2 28.1

D4 8.53 54.86 5.03 24 1.64 182 0.60 5.35

D5 9.58 52.34 4.86 23 1.46 182 2.42 19.5

D6 8.55 56.47 4.63 5 1.42 182 2.00 8.29

WH4271

D7 8.53 61.73 2.70 0 0.90 214 18.8 19.8

D8 8.51 58.11 3.68 0 1.26 214 0.90 1.32

D9 8.86 53.17 4.30 0 0.24 214 7.08 7.36

D10 8.49 56.07 4.97 0 0.94 214 1.39 3.20

D11 8.48 56.49 5.15 21 1.13 214 0.83 1.11

D12 8.49 55.30 4.67 11 2.27 214 0.41 0.97

Page iii of iii Report No. A13575 Detox

• Units and Abbreviations

a) Units g Grams

L Litres

m Metres

min Minutes

mol Moles

ppm Parts Per Million

w/w Weight Per Total Weight

b) Abbreviations CN

FREE Free Cyanide

CNP Cyanide by Picric Method

CNTOTAL

Total Cyanide

CNWAD

Weak Acid Dissociable Cyanide

RPM Rotations Per Minute

n(X) Moles of “X”

Page 1 of 7 Report No. A13575 Detox

1. INTRODUCTION

Mr Justin McKee, representing Ausenco, requested that ALS Ammtec conduct a defined program of cyanide detoxification testwork on a cyanidation leach tailings sample prepared in the ALS Ammtec gold laboratory and originating from Vista Gold Corporation’s Mt Todd Gold Project. This work included the following: �� SO

2/Air Cyanide Detoxification Testwork

The test program is presented as a flow diagram in Figure 1. The testwork was controlled by Mr Justin McKee, on behalf of Ausenco. Steven Rule supervised the program on behalf of ALS Ammtec.

2. SAMPLE RECEIPT AND PREPARATION

2.1 Sample Receipt

Two (2) samples of cyanidation leach tailings from Vista Gold Corporation’s Mt Todd Gold Project were received from the ALS Ammtec gold laboratory on 10th October 2011.

2.2 Sample Analysis

All assay samples generated during the course of the test program, were submitted to ALS Ammtec’s assay laboratory for analysis. The following analytical methods were employed: Copper, Iron, Nickel, Zinc in solution: Direct ICPOES

Cyanide – weak acid dissociable: Picric acid method

Cyanide – free: Silver nitrate titration

Cyanide speciation on the detoxification feed and products was performed by the Chemistry Centre of Western Australia, and the methods employed and results are outlined in their report in the appendices of this report.


3. TESTWORK METHODOLOGY

Several small-scale cyanide detoxification tests using the SO

2/air process were

conducted on two samples supplied by Vista Gold Corporation. The target was to achieve a final WAD cyanide level below 10 ppm.

3.1 SO2/Air Testwork

3.1.1 The SO2/Air Process

The SO2/air oxidation process has been found to oxidise cyanide to cyanate effectively

at bench, pilot and commercial scale. The chemistry has been simplified as follows:

�� → ��

�� 4� � 4 � 4� → 4�� 4��

� Reaction requires copper to be present to act as a catalyst and based upon the above reaction, the theoretical requirement of SO

2 to CN is 2.47 g (SO

2)/g(CN). However, due

to SO2 consumption by other chemical reactions the SO

2 dosage is greater; for

example, thiocyanate can also be oxidised according to the following proposed reaction:

�� 4� � 4 � 5� → �� 5�� The kinetics of thiocyanate oxidation is much slower than for cyanide however, so usual levels of thiocyanate in gold mill effluents do not generally adversely effect the SO

2

requirements of the process. The SO

2/Air oxidation process also destroys the metal cyanide complexes typically

present in gold mill effluents. The preferential order of metal cyanide complex removal is as follows:

�� The process is also capable of removing iron cyanide complexes from solution. The iron remains in the reduced ferrous state and is removed by precipitation of metal ferrocyanide compounds of the form Me

2Fe(CN)

6 where Me = Cu, Zn, Ni. Metals liberated

from the cyanide complexes of Cu, Zn and Ni are removed by precipitation of metal hydroxides at the reaction pH. When sodium metabisulphite is used as the SO

2 source, SO

2 is liberated according to the

following reactions:

��

�� → ��

�

�� → ��

�


Thus Na

2S

2O

5 produces two moles of SO

2 and one requires subsequent neutralisation.

The pH range for treatment is usually between 8.0 and 9.0 and is controlled by lime addition. The oxygen requirements for reaction are obtained from air as it bubbles through the reaction vessel solution.

3.1.2 Stoichiometric Requirements

In literature the stoichiometric requirements are generally reported as g(SO2)/g(CN

TOTAL)

and the requirement will be 2.47 g(SO2)/g(CN).

Additional requirements will be necessary for thiocyanate and thiosulphate oxidation and although estimates are calculated from experience data the actual requirement will become known from testwork. Also process reactions have an efficiency factor, which will be generally lower for slurry than for solution, and so calculations prior to testing assign an efficiency factor (e.g. 80% for solution).

3.1.3 Cyanide Detoxification Testing

The leach effluent solution was sampled and filtered before the tests to provide solution for Cu, Fe, Ni, Zn, CN

WAD and CN

FREE analysis. The remaining solution was used

as feed to the cyanide detoxification mini plant.

3.1.4 Reaction Vessel and Equipment Arrangement

The laboratory testing procedure involved the continuous operation of a mini plant which incorporated the following: (1) An agitated baffled reaction vessel of 800 mL live volume.

(2) Reagent dosage pumps for lime, sodium metabisulphite and copper sulphate solutions,

(3) pH measurement and controller for alkali (or acid) dosage to maintain reaction pH at ± 0.05.

(4) Aeration sparge capacity of 1-3 L/min/L reactor volume, typically 1 L/min/L rate, and

(5) Redox and dissolved oxygen measurement.


3.1.5 Operation

The initial level of CNWAD

in the leach effluent was estimated from the free cyanide titration together with analysis for Cu, Zn and Ni. The CN

WAD level was also determined

directly by a colorimetric method using picric acid reagent. The two values agreed well allowing the required concentration of sodium metabisulphite solution to be prepared. An operating pH of 8.5 was initially chosen for the testwork as this represents a typical optimum level for the SO

2/air detoxification process.

A residence time of nominally 60 minutes was chosen. The test program involved the following: (1) Calculations based upon effluent analysis.

(2) In continuous operation, feed was metered by pump at the desired rate into the reaction vessel. The desired amount of SO

2 was added in the form of a Na

2S

2O

5

aqueous solution. The pH was controlled at the desired set point by addition of a lime solution or acid solution on demand by means of a titration device. The solution or slurry was agitated vigorously at 1000 rpm and air was introduced at a rate of at least 1 L/min/L of reactor volume.

(3) A minimum of three reactor displacements are carried out for each test. Samples of treated effluent from each displacement were collected, filtered and analysed for Cu, Ni, Fe, Zn and CN

WAD.

3.1.6 Cyanide Analysis

Solutions were prepared for cyanide analysis using the following procedure: (1) Slurry samples were coarse filtered and the filtrate collected,

(2) The filtrate was refiltered through a fine glass fibre paper (0.45µm), then

(3) Samples for analysis were placed in plastic bottles (zero head space) and kept refrigerated until required for analysis.

Both feed effluent and treated effluent solutions were analysed by ALS Ammtec for CN

WAD using a direct spectrophotometric determination with picric acid reagent.

Cyanide determinations using this method have been identified in this report as CNP.


4. TESTWORK RESULTS

4.1 Summary of Results for Cyanide Detoxification Testwork

The key indicators for the detoxification testwork are presented in TABLE 4.1:

TABLE 4.1: SUMMARY OF DETOXIFICATION RESULTS

Test No. Cu

(mg/L)

Fe

(mg/L)

Ni

(mg/L)

Zn

(mg/L)

CNP

(mg/L)

CNTOTAL

(mg/L)

WH4270

Feed 34.10 11.40 0.65 5.30 182 213

D1 23.15 0.45 0.78 0.02 39.0 40.2

D2 20.40 0.75 0.10 0.58 39.5 41.6

D3 16.95 0.35 0.10 0.28 27.2 28.1

D4 1.55 1.70 0.25 0.04 0.60 5.35

D5 0.21 6.10 0.05 0.02 2.42 19.5

D6 2.10 2.25 0.38 0.04 2.00 8.29

WH4271

Feed 40.40 5.90 0.60 7.42 214 230

D7 3.54 0.35 0.05 0.47 18.8 19.8

D8 1.78 0.15 0.05 0.08 0.90 1.32

D9 1.56 0.10 0.05 0.05 7.08 7.36

D10 1.57 0.65 0.05 0.42 1.39 3.20

D11 1.24 0.10 0.05 0.03 0.83 1.11

D12 1.34 0.20 0.10 0.02 0.41 0.97


4.2 SO2/Air Testwork

4.2.1 Results

Details and results of the continuous cyanide detoxification tests appear in Appendix II. The results are briefly summarised in TABLE 4.2:

TABLE 4.2: SO2/AIR CYANIDE DETOXIFICATION RESULTS

Test No.

Test Conditions Solution Assays

pH Retention

Time (minutes)

Reagents Used Feed Effluent CNP

(mg/L)

Treated Effluent CNP

(mg/L)

Treated Effluent CNTOT

(mg/L) SO2

(g/g CNWAD) Cu2+

(mg/L) Lime

(g/g SO2)

WH4270

D1 8.72 60.14 2.67 26 0.50 182 39.0 40.2

D2 8.51 62.30 3.35 27 0.83 182 39.5 41.6

D3 8.49 54.34 3.49 24 2.36 182 27.2 28.1

D4 8.53 54.86 5.03 24 1.64 182 0.60 5.35

D5 9.58 52.34 4.86 23 1.46 182 2.42 19.5

D6 8.55 56.47 4.63 5 1.42 182 2.00 8.29

WH4271

D7 8.53 61.73 2.70 0 0.90 214 18.8 19.8

D8 8.51 58.11 3.68 0 1.26 214 0.90 1.32

D9 8.86 53.17 4.30 0 0.24 214 7.08 7.36

D10 8.49 56.07 4.97 0 0.94 214 1.39 3.20

D11 8.48 56.49 5.15 21 1.13 214 0.83 1.11

D12 8.49 55.30 4.67 11 2.27 214 0.41 0.97


4.2.2 Comments

Observations from the SO2/air testwork include the following:

• Sample WH4270 required a SO

2:CN ratio of 4.5-4.7 gSO

2/gCN to successfully

lower CN levels below the target of 10ppm.

• A copper dosage of 25-30ppm seemed to be most effective in eliminating dissolved iron, though in general copper dosage had a negligible effect on CN elimination.

• The lime dosage requirement was in the range of 1.4-1.6 g/gSO2.

• Raising the process pH seemed to be detrimental to the process, resulting in higher residual iron in solution.

• Sample WH4271 required a SO2:CN ratio of 4.2-4.4 gSO

2/gCN to successfully

lower CN levels below the target of 10ppm.

• Zero copper was required to eliminate the majority of dissolved iron, as it seems enough copper had leached into the solution from the residue to supply adequate copper for the process.

• The lime dosage requirement was in the range of 0.9-1.3 g/gSO2. Test D9 was

run at a slightly higher feed rate, which resulted in less lime being required to keep the pH over 8.5. This also suggests a lower residence time could be utilised while still achieving the target WAD CN.


FIGURE 1



APPENDICES


APPENDIX I

Leach and Optimum Detoxification Effluent Characterisation Results

Appendix I - Page 1 Report No. A13575 Detox

Table I.1

Leach & Optimum Detox Effluent Solution Analyses

Element WH4270 D6

2A+2B+3A+3B WH4271

D9 2A+2B+3A+3B

Slurry % Solids 60.7% NA 61.0% NA Solution SG 0.999 NA 0.999 NA

Solid SG 2.610 NA 2.605 NA CNfree 133 <1.0 133 <1.0

NaCNfree 250 <1.0 250 <1.0 CNwad 182 3.4 214 9.1

pH 10.28 8.59 10.38 9.45 ORP -98 NA -99 NA

ORP (Ag/AgCl) -539 -93 -544 -339 TDS 1400 4510 1520 4220 Ag 0.08 <0.02 0.04 0.60 Al 4.20 0.20 3.00 <0.20 As 1.20 1.00 0.80 <0.10 Au 0.03 0.04 0.04 0.06 Ba <0.05 0.10 <0.05 0.10 Bi <0.10 <0.10 <0.10 <0.10 Ca 15.0 43.5 14.5 59.0 Cd <0.05 <0.05 <0.05 <0.05 Cl 640 500 595 440 Co 0.45 0.85 0.45 0.45

CO3 400 40.0 290 40.0 HCO3 0.00 255 0.00 120

Cr <0.10 <0.10 <0.10 <0.10 Cu 34.1 0.92 40.4 2.92 Fe 11.40 0.80 5.90 <0.10 K 78.0 107 78.0 119 Li <0.05 <0.05 <0.05 <0.05 Mg 2.20 4.80 1.40 7.00 Mn <0.05 <0.05 <0.05 <0.05 Mo 0.30 0.35 0.25 0.35 Na 540 1265 580 1176 Ni 0.65 <0.05 0.60 0.10

NO2 0.04 0.24 0.24 NO3 14.7 23.5 10.8

P <1.0 <1.0 <1.0 <1.0 Pb 0.05 <0.05 <0.05 <0.05 Se <0.5 <0.5 <0.5 <0.5

SO4 50.0 1460 <50 1540 Sr 0.10 0.52 0.08 0.44 Ti <0.10 <0.10 <0.10 <0.10 V 0.04 <0.02 0.04 <0.02 Y <0.01 <0.01 <0.01 <0.01

Zn 5.30 0.02 7.42 0.08 Zr <0.05 <0.05 <0.05 <0.05

Note: Concentration is in ppm or mg/L unless otherwise stated


APPENDIX II

SO2/Air Detoxification Testwork Results

Appendix II - Page 1 Report No. A13575 Detox

TABLE SO2/Air Cyanide Detoxification Test D1 Sample: WH4270

Operating Conditions Client: Ausenco Date: 21 Oct 2011 Project: Mt Todd Gold Project Test: A13575 D1

Time pH KG Temp D.O Meta Cu Feed Lime CN load SO2 Ratio CuSO4.5H2O Ca(OH)2 Ret Time Solution

Ratio min mV oC ppm mL/hr mL/hr mL/hr mL/hr g/hr gSO2/gCN ppm gCa(OH)2/gSO2 min L/hr 0 8.50 -79 22 4.7 10.0 10.0 440 5.0 0.05 2.76 26 0.72 61.94 0.28 15 8.56 -175 4.5 10.0 10.0 440 5.0 0.05 2.76 26 0.72 61.94 0.28 30 8.58 -225 4.6 10.0 10.0 440 5.0 0.05 2.76 26 0.72 61.94 0.28 45 8.48 -263 4.8 10.0 10.0 440 5.0 0.05 2.76 26 0.72 61.94 0.28 60 8.72 -318 4.8 10.0 10.0 440 5.0 0.05 2.76 26 0.72 61.94 0.28 75 8.77 -335 4.9 10.0 10.0 460 5.0 0.05 2.64 25 0.72 59.38 0.29 90 8.85 -345 4.9 10.0 10.0 460 5.0 0.05 2.64 25 0.72 59.38 0.29 105 8.91 -358 4.9 10.0 10.0 460 5.0 0.05 2.64 25 0.72 59.38 0.29 120 8.94 -363 4.9 10.0 10.0 460 5.0 0.05 2.64 25 0.72 59.38 0.29 135 8.99 -373 4.9 10.0 10.0 470 0.0 0.05 2.58 25 0.00 58.78 0.29 150 8.68 -377 4.9 10.0 10.0 470 0.0 0.05 2.58 25 0.00 58.78 0.29 165 8.70 -374 4.9 10.0 10.0 470 0.0 0.05 2.58 25 0.00 58.78 0.29 180 8.69 -377 4.9 10.0 10.0 470 0.0 0.05 2.58 25 0.00 58.78 0.29 AVG 8.72 -305 22.0 4.8 10.00 10.00 455 3.46 0.05 2.67 26 0.50 60.14 0.29

Reactor Size (mL) 480 COMMENTS: CuSO4.5H2O Conc (gpl) 0.73 Feed, Meta, Copper and Lime flowrates determined from hourly average. Meta Conc (gpl) 20.52 20.52g/L Na2S2O5 Ca(OH)2 (gpl) 20.00 20g/L Lime Agitator (rpm) 1100 Air Flow (L/min/L) Max Solids (S.G.) 2.61 Estimated solids s.g Solids (% wt) 60.74 Soln (S.G.) 0.999 CNp determined by Picric Acid method (CNp is equivalent to CN(wad)) Slurry (S.G.) 1.598

Sample Time CNFREE CNp Cu Fe Ni Zn Calculated COMMENTS min ppm ppm ppm ppm ppm ppm CN total

FEED 0 132.7 181.6 34.10 11.40 0.65 5.30 213.4 DISP 1A 0-30 30 N/a 13.85 22.70 1.10 0.55 0.02 16.92 DISP 1B 30-60 60 N/a 41.68 31.30 1.20 0.65 0.02 45.03 DISP 2A 60-90 90 N/a 49.52 28.00 0.60 0.70 0.04 51.20 DISP 2B 90-120 120 N/a 54.20 26.60 0.70 0.75 0.02 56.16 DISP 3A 120-150 150 N/a 41.68 24.20 0.40 0.75 0.02 42.80 DISP 3B 150-180 180 N/a 36.24 22.10 0.50 0.80 0.02 37.64

AVERAGE SOLN ASSAYS 39.53 25.82 0.75 0.70 0.02 41.62 AVERAGE SOLN ASSAYS (LAST 2 SAMPLES) 38.96 23.15 0.45 0.78 0.02 40.22







































Operating Conditions Client: Ausenco Date: 3 Nov 2011 Project: Mt Todd Gold Project Test: A13575 D6






















































Operating Conditions Client: Ausenco Date: 3 Nov 2011 Project: Mt Todd Gold Project Test: A13575 D12








APPENDIX III

Chem Centre of WA Cyanide Speciation Reports

ChemCentreEnvironmental Chemistry Section

Report of Examination

097563

ALS Ammtec

6 MacAdam Place

Balcatta WA 6021

Attention: Steven Rule

Report on:

PO Box 1250, Bentley Delivery Centre

ABN 40 991 885 705

F +61 8 9422 9801

T +61 8 9422 9800

Bentley WA 6983

www.chemcentre.wa.gov.au

2 samples received on 03/11/2011

Purchase Order:

11E0881ChemCentre Reference:

LAB ID Material Client ID and Description

11E0881 / 001 solution A13575/WH4270 Head Sol

11E0881 / 002 solution A13575/WH4271 Head Sol

LAB ID

Client ID

Sampled

001 002

A13575/WH427

0

A13575/WH427

1

Analyte UnitMethod

Cyanide, free mg/L 130 150iCNF1WATI

Cyanide, WAD mg/L 170 210iCNW1WAAA

Cyanide, total mg/L 240 280iCNT1WTAA

Cyanate mg/L 64 81iCNO1WAIC

Thiocyanate mg/L 150 160iCNSP1WSLC

Chromium Cyanide mg/L <0.5 <0.5iCNSP1WSLC

Cobalt Cyanide mg/L <0.1 <0.1iCNSP1WSLC

Copper Cyanide mg/L 53 51iCNSP1WSLC

Gold Cyanide mg/L <0.5 <0.5iCNSP1WSLC

Iron (II) Cyanide mg/L 13 6.3iCNSP1WSLC

Iron (III) Cyanide mg/L <0.1 <0.1iCNSP1WSLC

Nickel Cyanide mg/L 0.6 0.6iCNSP1WSLC

Silver Cyanide mg/L <5 <5iCNSP1WSLC

Method Method Description

Free Cyanide by Silver Nitrate titration (APHA 4500 CN-D).iCNF1WATI

Cyanate in water by Ion Chromatography (In House).iCNO1WAIC

Cyanide metal species (as mg/L of the metal) by HPLC (In House)iCNSP1WSLC

Total cyanide including thiocyanate by SFAAS (APHA 4500 CN-O).iCNT1WTAA

Weak acid dissociable (WAD) cyanide by SFAAS (APHA 4500 CN-O).iCNW1WAAA

These results apply only to the sample(s) as received. Unless arrangements are made to the contrary, these samples will

be disposed of after 30 days of the issue of this report.

This report may only be reproduced in full.

Page 1 of 211E0881

http://www.chemcentre.wa.gov.au

28-Nov-2011

Environmental Chemistry Section

Science Business Manager

Jenny McGuire

Page 2 of 211E0881

Report No. A13575 Part 1

APPENDIX XXIV

Mt Todd Master Composite

Mixer Design

ALL MIXING APPLICATION DATA, MIXING EQUIPMENT DESIGN, AND RELATED KNOW-HOW DISCLOSED HEREIN ARE CONFIDENTIAL AND THE PROPERTY OF LIGHTNIN MIXERS. NO USE OR DISCLOSURE THEREOF MAY BE MADE WITHOUT OUR WRITTEN PERMISSION.

MIXER TESTWORK FOR

MT TODD PROJECT

BY

SPX FLOW TECHNOLOGY AUSTRALIA PTY LTD

12th September -14th October 2011


Scope Ausenco is conducting a feasibility study on behalf of Vista Gold to evaluate the viability of the development of a mineral deposit at Mt Todd, in Australia. The Carbon-in-Leach (CIL) agitators are required to uniformly mix and suspend gold-bearing leached slurry and activated carbon. Floating of carbon is to be prevented, and mechanical damage to the carbon shall be minimized. A settled tank should be able to be re-slurried on start-up without overloading electrical motors or other mechanical components. SPX has been requested to perform mixing testwork (pilot plant set-up), to see if there is any difficulty for slurry with 65%wt solids content. Mixing performance will also be observed for 45%wt, 50%wt, 55%wt and 60%wt slurry. Results from this testwork and viscosity measurement, will be used by SPX for sizing the CIL tank agitator (full-scale tank design). The samples for this testwork program were prepared by ALS Ammtec.

A13575 Mt Todd master composite (P80 = 125 µm) adjusted to 65%wt slurry using Perth tap water. Lime added to adjust slurry pH to 10.5 ~ 11

Activated Haycarb carbon Testwork Procedure

(1) Combine the 65%wt slurry samples into test-tank. The tank used, is clear Perspex, 360mm diameter, 480mm in height. The liquid level, obtained was 395 mm, thus the Z/T ratio of 1.1 (whereby Z = liquid depth and T = tank diameter).

(2) Homogenize the slurry, to achieve uniform suspension, using the Lightnin portable mixer. The mixer is mounted on a support structure, vertically on-center. A VVVF drive (inverter) is used to vary the mixing speed (and thus power input to the tank).

(3) Sample from top and bottom of the tank, to get %wt moisture using the moisture balance. This is to check for homogeneity of the slurry.

%wt solids = 100% - %wt moisture

When desired %wt solids is obtained, check that the pH of the slurry is about 10.5 – 11. Add lime to the slurry, to adjust to the required pH range.

Measure the viscosity of the sample, using Brookfield viscometer.


(4) Weigh the activated carbon (15 g per liter of slurry) and wet it prior to adding into the tank.

Use a sieve to filter off the carbon whenever - taking samples for moisture balance or viscometer measurements, - adding water or removing slurry to change the %wt solids. Put the filtered carbon back into the tank, to maintain carbon concentration (15 g/l) throughout the testwork program.

(5) Set the design parameters, e.g. - Impeller type, diameter, locations - Speed (check the speed using tachometer)

(6) After running the mixer for sufficient time to allow performance to stabilize, observe, e.g - Carbon floating at the top of the tank (unsatisfactory) or is the carbon uniformly suspended in

the slurry (process requirement)?

- Flow at the bottom of the tank when viewed from the side and also when viewed from the bottom of the tank? (place a mirror at bottom of the tank to view the reflection). We refer to the zone at bottom corners of the tank where there is no flow, as the fillet.

- Stagnation at the baffles? - Dewatering at the surface? - Surface motion such as welling at the surface? Are there vortices forming (swirling around

the shaft)?


Carbon floating at surface Welling at the surface. No “carbon-floating” seen. (unsatisfactory)

Check for fillet across tank bottom Check for fillet from tank bottom. As tank diameter is 360mm, maximum of 36mm fillet height is acceptable.

For a quick check of carbon distribution, draw known volume of sample from top and bottom of tank, and sieve out the carbon. Carbon distribution will look about the same if there is uniform suspension of the activated carbon in the slurry.

(7) Change to next data point (different %wt solid content). Keep the slurry level (liquid depth) at 390 ± 5mm, so as to keep the Z/T ratio close to 1.1 Repeat steps (2), (3), (5) and (6) for each data point.


Viscosity measurements The viscosity of the non-Newtonian slurry was measured using the Brookfield viscometer, DV-II + Pro. The viscometer gives readings of the Shear Stress, Shear Rate, Apparent Viscosity and % torque. Readings within the % torque range of 20 to 80% were used to plot the graph below.

i The slurry exhibits a typical “power law” fluid rheology over the shear rate range of interest to mixed tanks.


Lightnin considers the viscosity at reference shear rate of 2.3 s-1, for agitator selection.

Baffles should be installed for on-center mounted mixers. Baffles assure that the entire batch will be brought through the zone of the impeller where there is maximum agitation intensity. Baffles prevent excessive swirling and vortexing. It is important not to over-baffle or under-baffle the tank. In water-like fluids, the baffle width is one-twelfth the tank diameter. However as viscosity increases, baffle width should be reduced accordingly. This is because as batch viscosity increases, so does the viscous drag on the tank wall and other internals, thereby stagnation occurs.


Design parameters

Effect of Power Scale up of power requirement is by a correlation Power (Volume)x , where X depends on the process and the viscosity. This factor is proprietary information and is determined through our years of experience. We calculate the power required for the pilot plant test tank, to predict the power level that may be expected in full-scale tank, based on same D/T ratio. (where D = impeller diameter and T = tank diameter). In the turbulent region and for same slurry property, power consumption is proportional to N3D5, where N = impeller speed, D = impeller diameter. The ratio of P to N3D5ρ is proportional to the power number, Np (dimensionless), where ρ = slurry density.

Effect of impeller spacing and location

When using multiple impellers, it is necessary to place them in the proper position to achieve an efficient flow pattern. Axial flow impellers (like our high efficiency A310 aerofoil impeller) normally reinforce the flow from the other impeller with less tendency toward developing separate impeller agitation zones.

Impeller "off-bottom” distance is measured from lower impeller’s horizontal centreline to the tank bottom. For suspension of solids, if the lower impeller is located very close to the tank bottom, the condition may help keep the tank bottom clear of solids but at a cost of reduced bulk homogeneity.

“Coverage” is measured from the static liquid surface to the horizontal centreline of the upper impeller. To avoid splashing and the formation of a vortex, the top impeller should not be located too close to the tank surface. A deep vortex can cause air or vapour entrainment.


Observations of mixing performance

65% wt solids slurry The slurry is moderately viscous at 2313 cP at reference shear rate of 2.3 s-1. There is some solids build-up at the baffles due to stagnation. Several combinations of impeller speeds, types, diameters and locations were tested. It was observed for all these combinations, that carbon floated, forming a raft at surface. Mixing performance looks acceptable at the tank bottom. We expect carbon distribution being a problem for full-scale tank. We do not recommend 65%wt solids for the CIL process, as it was not possible to achieve acceptable performance.

60% wt solids slurry The 60% wt slurry is more free-flowing as compared to the difficult 65% wt slurry. The viscosity is lower at 1541 cP and the mixing situation was greatly improved. Overall, a satisfactory result was achieved. Carbon distribution seems good, and the fillet height at bottom of the tank is acceptable. Mixing performance is satisfactory even when we adjusted the D/T ratio to scale-up to 5000 m3 tank.

55% wt solids slurry The slurry is less viscous at 618 cP, but it is still a hindered settling suspension. As the solids concentration decreases, the mixing gets easier. However when we reduced the speed, the fillet height at bottom of the tank increases to more than 10% tank diameter. Thus we will keep to the same agitator selection for 60% wt and 55% wt solids slurry.

50% wt solids slurry The slurry viscosity decreased to 175 cP. At reduced speed, there is good mixing both at surface and bottom of the tank. Thus if this is the operating condition instead of 60% wt slurry, we can select an agitator with smaller motor.

45% wt solids slurry The slurry viscosity is 45 cP. When the mixer is turned off, the suspension is seen to be free-settling. Dewatering at the liquid surface was observed. However this effect could be removed if the upper impeller is placed nearer to the liquid surface. Mixing performance is acceptable, at this speed and impeller spacing, for 60% wt slurry. Thus we would offer the S783Q175 (132 kW, 16.7 rpm) gearbox with dual A310 impellers for the CIL tank agitators.


Conclusion

- We do not recommend 65%wt solids for the CIL tank due to the difficulty in achieving uniform solid suspension, and re-slurrying upon start-up.

- Our Lightnin S783 drive is required for all solids concentration (except 65% wt), in 4500-5000 m3 live volume. Some minor savings at lower solids concentration due to smaller motor required.

- A dual down-pumping axial flow impeller combination is recommended with impeller / tank diameter ratio about 0.33

- The tank would require 3 baffles equi-spaced at 120 degrees. Baffle width to be recommended by supplier based on slurry viscosity and agitator selection.

- For 5000 m3 live volume, the optimal tank size is 18000 mm diameter, with slurry height 1.1 x tank diameter. Any changes to the tank dimensions could have a significant impact on agitator selection and cost.

- The budgetary quotation for the CIL tank agitator has been submitted to Ausenco in response to their enquiry 2131-RFQ-012.


APPENDIX XXV


Thickener Design

MT TODD VISTA GOLD TEST REPORT AUGUST 2011 CYCLONE OVERFLOW GOLD SLURRY S1817

OUTOTEC (AUSTRALIA) PTY LTD Page 1 of 4 CONFIDENTIAL

SUPAFLO® THICKENER

INTERPRETATIONS AND RECOMMENDATIONS

OF TEST DATA REPORT S1817

CLIENT : ALS Ammtec/Vista Gold APPLICATION : Thickening of cyclone overflow slurry

prior to gold leach stage TEST EQUIPMENT : 99 mm Diameter Supaflo® High Rate

Thickener TEST DATE : 22 August 2011 FILE REFERENCE No. : S1817_B REFERENCE TO : S1817

DISTRIBUTION

Client: Wayne Harding, ALS Ammtec [email protected]

Other(s): ALS Ammtec Outotec Files

CONFIDENTIALITY – COMMERCIAL IN CONFIDENCE This report remains the property of Outotec Pty Ltd and must not be disclosed to any third party not appearing on the distribution list above or used or copied in any form whatsoever without the prior written consent of Outotec Pty Ltd.

mailto:[email protected]



CONTENTS SECTION PAGE No. 1.0 Interpretation of Test Data and Results 3 2.0 Recommended Thickener Design Specifications 4



1.0 INTERPRETATIONS OF TEST DATA AND RESULTS

The testwork showed that high rate thickening of the: Mt Todd Vista Gold overflow slurry sample produced underflow of 65.1 % solids (w/w) at a flux rate of 0.82 t/(m2·h), exceeding the target density of 50 – 65 %w/w solids. The associated yield stress measurement was 36 Pa. The overflow quality was very good, and measuring < 100 mg/L suspended solids. This was achieved with Magnafloc 10 dosage of 6 g/t. It could be reasonably expected that a full-scale thickener would achieve underflow density around 2 - 3 % solids (w/w) higher than the small-scale rig used in this testwork. Outotec's experience with testwork and full-scale operation of thickeners allows us to reliably include an estimate of 2 – 3 % increase in thickener underflow density when comparing the testwork to a full-size thickener. With this in mind, the size of thickener required for your desired outcomes can be evaluated from the (un-adjusted) testwork tables below.

Please feel free to call myself or our Technology Leader, Chris Greenwood, if you would like to discuss the appropriate thickener sizing.

Yefrey Joe



2.0 RECOMMENDED THICKENER DESIGN SPECIFICATIONS

Overflow Thickener

Run Flux Calc. Solids Liquor RR Type Dose Calc. Solids YS Solids Diameter

No. (t/(m2·h)) (% (w/w)) (m/h) (g/t) (% (w/w)) (Pa) (mg/L) (m)

1 0.20 12.5 1.50 M 10 18 70.9 141 13 96

2 0.41 12.5 3.02 M 10 18 69.1 103 48 67

3 0.82 12.5 6.03 M 10 18 65.2 54 54 47

4 1.23 12.5 9.04 M 10 18 63.1 39 97 39

5 1.64 12.5 12.05 M 10 18 63.2 34 154 34

6 0.82 12.5 6.01 M 10 12 65.4 50 22 47

7 0.82 12.5 6.01 M 10 6 65.1 36 33 47

Feed Flocculant Underflow

Sizings based on a feed rate of 1450 t/h. The thickener recommendation is for an Outotec High Rate thickener with Outotec Vane feedwell. Yefrey Joe


OUTOTEC (AUSTRALIA) PTY LTD Page 1 of 12

SUPAFLO® THICKENER TEST DATA REPORT

CLIENT : ALS Ammtec/Vista Gold APPLICATION : Thickening of gold cyclone overflow

slurry prior to gold leach stage TEST EQUIPMENT : 99 mm Diameter Supaflo® High Rate

Thickener TEST DATE : 22 August 2011 FILE REFERENCE No. : S1817

DISTRIBUTION

Client: Wayne Harding, ALS Ammtec [email protected]

Other(s): ALS Ammtec Outotec Files




CONTENTS SECTION PAGE No. Executive Summary 3 1.0 Test-work Objectives 4 2.0 Samples Tested 4 3.0 Sample Characterisation 4

3.1 Flocculant Selection 5 3.2 Feed Dilution Tests 5

4.0 General Batch Dynamic Thickening Test Method 5 5.0 Test Results 7 5.1 Flocculant Selection 7 5.2 Dynamic Thickening Tests 8 Conclusion 9 Picture 1 10

Mt Todd Vista Gold Slurry Run 7

Appendix 1 11 Mt Todd Vista Gold slurry Particle Size Distribution Data with LASER Appendix 2 12 Mt Todd Vista Gold slurry Rheological Curve from Run 7



Executive Summary The testwork showed that high rate thickening of the: Mt Todd Vista Gold cyclone overflow slurry sample produced underflow of 65.1 % solids (w/w) at a flux rate of 0.82 t/(m2·h), exceeding the target density of 50 – 65 %w/w solids. The associated yield stress measurement was 36 Pa. The overflow quality was very good, being clear and measuring < 100 mg/L suspended solids. This was achieved with Magnafloc 10 dosage of 6 g/t. Yefrey Joe The sole purpose of this report is to provide the experimental results obtained from the test work performed and the methods used to obtain them. The interpretation of the experimental results obtained and any equipment recommendations made are provided in a separate report marked commercial in confidence – property of Outotec (Australia) Pty Ltd.



1.0 TEST-WORK OBJECTIVES

The objective of this test work was to carry out dynamic thickening tests on the gold cyclone overflow slurry and so determine appropriate parameters for thickener sizing and design.

2.0 SAMPLES TESTED

One sample of Mt Todd Vista gold cyclone overflow slurry was delivered to Outotec’s Melbourne laboratory as damp filter cake. The total weight was approximately 19.2 kg. The sample was diluted to 30.9 %w/w solids with Melbourne water. The pH of the slurry was adjusted with lime to pH 10.4 No diluent water was received with the sample. Melbourne tap water was to be used as diluent and was adjusted with lime to pH 10.2 The specific gravity measured was 2.85 t/m3 All tests were conducted at ambient temperature of 12 – 14oC

3.0 SAMPLE CHARACTERISATION The solids from the feed slurry and the underflow samples generated from each thickening test were washed into trays and dried overnight in an

oven at around 100 C. The suspended solids in the overflow samples collected from each test were determined by filtering 100 mls of overflow liquor through pre-weighed Whatman GF/C filter discs using a vacuum filtration unit. The collected overflow solids were also washed thoroughly with Melbourne tap

water prior to oven drying at approximately 100 C. The filter discs were then re-weighed to determine the suspended solids content. As a standard part of the test work protocol, a small but representative sample of each feed slurry is collected for particle size distribution. This analysis was carried out by HRL laboratory in Melbourne. Please be aware that laser sizing works on a different principle to screening and as such sizing data is not directly comparable between the two techniques.



The presence of highly non spherical particles affects the sizing results in both cases. The presence of both high and low solid SG fractions within the same sample can also affect the distribution results. Ultrasonic action is often used to disperse samples before measurement and this can affect fragile solids such as clays The results, in graphical form, are shown in Appendix 1.

3.1 FLOCCULANT SELECTION

We used BASF products for the flocculant selection test work. This should not be viewed as an endorsement of this particular supplier and other equivalent products may be used. The flocculants used for the screening were Magnafloc’s 800HP, 10, 342, 919 and 1011. Based on the static cylinder test results obtained on the sample, Magnafloc 10 was selected as the best polymer and was used in all test work.

3.2 FEED DILUTION TESTS

Dilution tests were conducted using Outotec’s optimum dilution test method. Outotec’s optimum dilution method finds the optimum feed solids concentration for use with Outotec’s Vane Feedwell. The optimum feed dilution concentration for the sample was found to be around 12.5% w/w solids

4.0 GENERAL BATCH DYNAMIC THICKENING TEST METHOD

For each sample, the stock slurry was kept agitated in a 50 litre baffled tub. Agitation was achieved using a Rushton Turbine style prop mounted just clear of the bottom of the tub and a variable speed drive. This allows good agitation as well as maximum sample availability. Testing was conducted at the slurry's natural pH of 10.4 and at ambient temperature of 12 to 14oC. Stock slurry was drawn from the agitated tub by variable speed peristaltic pump and fed into the feed well of the test thickener. This slurry was then diluted 'on the fly' with the diluent water using a second pump. The target density, after dilution, was 12.5 %w/w.



Flocculant was added at a set flow rate but at a range of concentrations depending on test conditions. Stock flocculant solution was made up in Melbourne tap water at 0.25%w/v (2.5 gpl) and then diluted to the required

dose strength ( 0.025%w/v) with tap Water as required. The diluted flocculant was dosed into the diluent water line in one increment before the dilution step. The length and diameter of each section of feed line was kept constant to give similar mixing and flocculation conditions between tests. The flocculated solids bed was raked continuously at, typically, 2 rpm for the entire test during which time a bed of about 240 mm in height was formed. Two rotating picket was used in all the tests, in conjunction with two static pickets.

Once the bed had reached this depth, the underflow sample was taken using a positive displacement pump. The solids concentration was then determined as described above in Section 3.0.

Overflow samples were collected at a bed height of approximately 160 mm during each test. These samples were analysed to determine the suspended solids content as described above in Section 3.0.

Underflow slurry yield stress was measured using a Haake VT550 rotational viscometer fitted with a four bladed vane sensor. The sensor was gently immersed into each slurry sample and rotated at a constant shear rate of 0.1 sec-1. A shear stress versus time graph is generated electronically in real-time with the peak of this curve equating to the yield stress.



5.0 TEST RESULTS 5.1 Flocculant Screening

0

50

100

150

200

0 5 10 15 20 25

Sett

le R

ate

(m/h

)

Flocculant Dose(g/t)

Mt Todd-Vista Gold slurry Flocculant Screening Settle Rates

M 800HP

M 10

M 342

M 5250

M 919

Chart 1. Flocculant settling rates of the Mt Todd Vista Gold slurry.

Chart 1, above, shows the settling rates of the sample achieved in 500 mL static cylinder tests.

The optimum flocculant dosage that achieved both fast settling rates and excellent clarity were achieved with Magnafloc 10 at 20 g/t. It was tested for use in dynamic testing, starting at 18 g/t.



5.2 Dynamic Thickening Tests

Overflow

Run Flux Calc. Solids Liquor RR Type Dose Calc. Solids YS Solids

No. (t/(m2·h)) (% (w/w)) (m/h) (g/t) (% (w/w)) (Pa) (mg/L)

1 0.20 12.5 1.50 M 10 18 70.9 141 < 100

2 0.41 12.5 3.02 M 10 18 69.1 103 < 100

3 0.82 12.5 6.03 M 10 18 65.2 54 < 100

4 1.23 12.5 9.04 M 10 18 63.1 39 < 100

5 1.64 12.5 12.05 M 10 18 63.2 34 154

6 0.82 12.5 6.01 M 10 12 65.4 50 < 100

7 0.82 12.5 6.01 M 10 6 65.1 36 < 100

Feed Flocculant Underflow

Table 1. Dynamic thickening testwork results. Run 1 to 5 were run at increasing flux rates and at the same flocculant dosage of 18 g/t each run. The first run employed a flux rate of 0.20 t/(m2·h). This achieved an underflow density of 70.9 % solids (w/w) with accompanying yield stress measured 141 Pa. The overflow quality was good, being clear and measuring < 100 mg/L suspended solids. The second run was conducted at flux rate of 0.41 t/(m2·h). This reduced the underflow density to 69.1 % solids (w/w) and yield stress to 103 Pa. The overflow quality was again good, measuring < 100 mg/L suspended solids. The third run was done at 0.82 t/(m2·h). This again reduced the underflow density to 65.2 % solids (w/w) and yield stress to 54 Pa. The overflow quality was again good, measuring < 100 mg/L suspended solids. The fourth run was done at flux rate of 1.23 t/(m2·h) and produced an underflow density of 63.1 % solids (w/w) with yield stress to 39 Pa. The overflow quality was good, measuring < 100 mg/L suspended solids. Run 5 was done at flux rate of 1.64 t/(m2·h). The underflow produced was 63.2%w/w solids with yield stress of 34 Pa and overflow clarity of 154 ppm. Run 6 was run at flux rate 0.82 t/(m2·h) but at reduced flocculant dosage of 12 g/t. The underflow density obtained was 65.4 %w/w solids with yield stress of 50 Pa and overflow clarity < 100 ppm. Run 7 was run at an even reduced flocculant dosage of 6 g/t at flux rate of 0.82 t/(m2·h). The underflow density was maintained at 65.1 %w/w solids with yield stress of 36 Pa and overflow clarity of < 100 ppm



Conclusion The Mt Todd Vista Gold testwork showed that a flux rate up to 0.82 t/(m2·h) and Magnafloc dosage of 6 g/t would produce underflow density of 65.1 %w/w solids exceeding the target of 50 - 65 % with excellent overflow clarity of < 100 ppm. Yefrey Joe Test Work Engineer ______________________________________________ Outotec Pty Ltd 12 Kitchen Road, Dandenong, Victoria 3175, Australia Tel: +61 3 9566 5800 Mobile: 0400 435 240 Email: [email protected]




Picture 1: Mt Todd Vista Gold slurry at run 7. Note the excellent overflow quality.



APPENDIX 1

Mt Todd Vista Gold Tailings PARTICLE SIZE DISTRIBUTION DATA with LASER

(To be provided when available)



APPENDIX 2

Mt Todd Vista Gold Tailings Rheological Curve from Run 7


APPENDIX XXVI


Viscosity Testwork

Details and Results

Job No. : A13575 Date : Aug-2011 Use : Perth Tap Water

Sample System Dial Viscosity Viscosity Shear Rate Shear Stress Temp. Torque

Details Number Speed η η y M

(Pas) (cps) (s-1) (Pa) (°C) (mNm)

SAMPLE ID : 6 1 1.069 1069 4.2 5.0 18.8 0.32

Master Composite 2 1.051 1051 7.4 6.1 0.39

Perth Tap Water 3 0.934 934 13.1 7.2 0.46

% SOLIDS: 65 4 0.567 567 21.9 8.5 0.54

Grind size: P80 125µm 5 0.365 365 38.9 10.1 0.64

Natural pH: 8.38 6 0.246 246 67.4 11.9 0.76

Lime Added (g): .64 7 0.210 210 119.2 20.0 1.27

Adjusted pH: 11.00 8 0.202 202 209.5 35.8 2.28

SAMPLE ID : 6 1 1.512 1512 4.2 3.3 19 0.21


Perth Tap Water 3 0.726 726 13.1 6.0 0.38

% SOLIDS: 60 4 0.465 465 21.9 7.1 0.45

Grind size: P80 125µm 5 0.289 289 38.9 9.3 0.59

Natural pH: 10.83 6 0.217 217 67.4 10.7 0.68

Lime Added (g): Nil 7 0.173 173 119.2 18.2 1.16

Adjusted pH: 10.83 8 0.148 148 209.5 33.0 2.10

SAMPLE ID : 6 1 0.043 43 4.2 2.8 19 0.18


Perth Tap Water 3 0.063 63 13.1 4.9 0.31

% SOLIDS: 55 4 0.075 75 21.9 6.6 0.42

Grind size: P80 125µm 5 0.087 87 38.9 9.3 0.59

Natural pH: 10.61 6 0.098 98 67.4 9.7 0.62

Lime Added (g): Nil 7 0.103 103 119.2 17.1 1.09

Adjusted pH: 10.61 8 0.118 118 209.5 31.8 2.02

SAMPLE ID : 6 1 0.000 0 4.2 0.0 19.1 0.00


Perth Tap Water 3 0.000 0 13.1 0.0 0.00

% SOLIDS: 50 4 0.000 0 21.9 0.0 0.00

Grind size: P80 125µm 5 0.000 0 38.9 0.0 0.00

Natural pH: 10.40 6 0.000 0 67.4 1.3 0.08

Lime Added (g): 0.12 7 0.036 36 119.2 4.2 0.27

Adjusted pH: 11.00 8 0.053 53 209.5 11.0 0.70

SAMPLE ID : 6 1 0.000 0 4.2 0.0 19.4 0.00


Perth Tap Water 3 0.000 0 13.1 0.0 0.00

% SOLIDS: 45 4 0.000 0 21.9 0.0 0.00

Grind size: P80 125µm 5 0.000 0 38.9 0.0 0.00

Natural pH: 10.69 6 0.000 0 67.4 1.3 0.08

Lime Added (g): Nil 7 0.032 32 119.2 3.6 0.23

Adjusted pH: 10.69 8 0.048 48 209.5 11.0 0.70

VISCOSITY TEST REPORT - BHOLIN VISCO 88

VISTA GOLD CORP, MT TODD GOLD PROJECT - MASTER COMPOSITE (P80 125µm)

Grind Slurry Slurry Pulp Bohlin Visco 88

Size pH Temp. Density Viscosity @ Shear Rate ( Sec-1

)

P80 % Solids 4.2 7.4 13.1 21.9 38.9 67.4 119.2 209.5

(µm) (ºC) (w/w) (cps) (cps) (cps) (cps) (cps) (cps) (cps) (cps)

11.00 18.8 65.0 1069 1051 934 567 365 246 210 202

10.83 19.0 60.0 1512 1042 726 465 289 217 173 148

10.61 19.0 55.0 43 51 63 75 87 98 103 118

11.00 19.1 50.0 0 0 0 0 0 0 36 53

10.7 19.4 45.0 0 0 0 0 0 0 32 48

NOTES : 1. PERTH TAP WATER UTILISED FOR SLURRY PREPARATION.

A13575: VISTA GOLD CORP, MT TODD GOLD PROJECT FEASIBILITY STUDY

VISCOSITY TESTWORK

Master Composite 125

Sample

Identity

0

500

1000

1500

2000

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 210

VIS

CO

SIT

Y (

cp

s)

SHEAR RATE (SEC-1 )

VISCOSITY Vs SHEAR RATE

65% SOLIDS (w/w)

60% SOLIDS (w/w)

55% SOLIDS (w/w)

50% SOLIDS (w/w)

45% SOLIDS (w/w)

Grind Slurry Slurry Pulp Bohlin Visco 88

Size pH Temp. Density Shear Stress @ Shear Rate ( Sec-1

)

P80 % Solids 4.2 7.4 13.1 21.9 38.9 67.4 119.2 209.5

(µm) (ºC) (w/w) (Pa) (Pa) (Pa) (Pa) (Pa) (Pa) (Pa) (Pa)

11.00 18.8 65.0 5.0 6.1 7.2 8.5 10.1 11.9 20.0 35.8

10.83 19.0 60.0 3.3 4.2 6.0 7.1 9.3 10.7 18.2 33.0

10.61 19.0 55.0 2.8 3.6 4.9 6.6 9.3 9.7 17.1 31.8

11.00 19.1 50.0 0.0 0.0 0.0 0.0 0.0 1.3 4.2 11.0

10.69 19.4 45.0 0 0 0 0 0 1 4 11

NOTES : 1. PERTH TAP WATER UTILISED FOR SLURRY PREPARATION.

A13575: VISTA GOLD CORP, MT TODD GOLD PROJECT FEASIBILITY STUDY

VISCOSITY TESTWORK

Master Composite 125

Sample

Identity

0.0

10.0

20.0

30.0

40.0

0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 90.0 100.0 110.0 120.0 130.0 140.0 150.0 160.0 170.0 180.0 190.0 200.0 210.0

SH

EA

R S

TR

ES

S (

Pa)

SHEAR RATE (SEC-1 )

SHEAR STRESS Vs SHEAR RATE

65% SOLIDS (w/w)

60% SOLIDS (w/w)

55% SOLIDS (w/w)

50% SOLIDS (w/w)

45% SOLIDS (w/w)


APPENDIX XXVII

Mt Todd Master Composite (New)

LIMS Testwork

Details and Results

PROJECT A13575

CLIENT VISTA GOLD CORPORATION

TEST DESCRIPTION DRY LIMS MAGNETIC SEPARATION TESTWORK @ 1100G

MT TODD MASTER COMPOSITE

GRIND P100 : 3.35 mm

DATE Aug-11

MASS

(g) Au (g/t) Ag (ppm) Cu (ppm) Fe (%) S (%) Mass Au Ag Cu Fe S

MAGS 445.4 2.69 1.7 1085 10.9 4.82 11.16 39.85 26.25 20.15 21.91 49.41

NON‐MAGS 3545.4 0.51 0.6 540 4.88 0.62 88.84 60.15 73.75 79.85 78.09 50.59

CALC. FEED 3990.8 0.75 0.72 601 5.55 1.09 100.00 100.00 100.00 100.00 100.00

ASSAY FEED 4000.0

PROJECT A13575

CLIENT VISTA GOLD CORPORATION

TEST DESCRIPTION WET LIMS MAGNETIC SEPARATION TESTWORK @ 1100G

MT TODD MASTER COMPOSITE

GRIND P80 : 125 µm

DATE Oct-11

MASS

(g) Au (g/t) Ag (ppm) Cu (ppm) Fe (%) S (%) Mass Au Ag Cu Fe S

MAGS 78.66 2.97 INS 830 56.2 30.9 1.66 5.49 N/A 2.47 16.58 42.04

NON‐MAGS 4653.8 0.87 1.4 555 4.78 0.72 98.34 94.51 N/A 97.53 83.42 57.96

CALC. FEED 4732.46 0.90 N/A 560 5.63 1.22 100.00 100.00 N/A 100.00 100.00 100.00

ASSAY FEED 5000.0

STREAMASSAY Distribution [%]

SAMPLE

ASSAY Distribution [%]STREAM

SAMPLE


APPENDIX XXVIII

2010 New Drill Core/ Mt Todd Master Composite (New)

Conventional Crush and

HPGR Crush Product Analysis

Details and Results

ANALYTE UNIT

Au1 g/t 0.90

Au2 g/t 0.93

Au3 g/t N/A

Au4 g/t N/AAg ppm 0.9As ppm 260Al % 7.12Ba ppm 400Be ppm 4.8Bi ppm <10

Ctotal % 0.15

Corganic % <0.03

CO32- % 0.75

Ca % 3000Cd ppm <5Co ppm 20Cr ppm 50Cu ppm 488

CN Sol. Cu ppm 188Fe % 5.52Hg ppm 0.2K % 3.20Li ppm 20

Mg % 1.28Mn ppm 400Mo ppm <5Na ppm 2260Ni ppm 25P ppm 700

Pb ppm 375Pd1 ppm <0.02

Pd2 ppm <0.02

Pt1 ppm <0.02

Pt2 ppm <0.02

Stotal % 1.08

Ssulfide % 0.86Sb ppm 1.5

SiO2 % 65.0Sn ppm <50Sr ppm 16Te ppm <0.2Th ppm 18Ti ppm 3200U ppm 3.8V ppm 78Y ppm 18Zn ppm 728Zr ppm 145

True SG g/mL 2.8330

VISTA GOLD CORPORATION

A13575 MT TODD PROJECT FEASBILITY STUDY

"NEW MASTER COMPOSITE" - COMPREHENSIVE HEAD ANALYSIS

PLANT FEED MASTER COMPOSITE

ORE SAMPLE MOISTURE COMPACTED * UNCOMPACTED *

IDENTITY CONTENT (%) BULK DENSITY (g/ml) BULK DENSITY (g/ml)

MASTER COMP. -32mm HPGR FEED 0.00 1.4985 1.3326

MOISTURE ADJ'D MASTER COMP. -32mm HPGR FEED 2.78 1.7623 1.3546

* Uncompacted Bulk Density Determinations undertaken at specified moisture content.

A13575 VISTA GOLD / KOEPPERN MACHINERY AUSTRALIA PTY LTD

MT TODD 2010 DRILL CORE MASTER COMPOSITE -32mm FEED : MOISTURE & BULK DENSITY DETERMINATIONS

Operation Size Weight Weight Weight

(m) (g) (%) % <

Screening 31500 0.0 0.00 100.00

26500 2646.8 26.44 73.56

19000 2725.0 27.22 46.34

16000 757.6 7.57 38.77

11200 733.0 7.32 31.45

8000 561.5 5.61 25.84

5600 815.7 8.15 17.69

4000 472.5 4.72 12.97

2800 321.3 3.21 9.76

2000 226.3 2.26 7.50

1400 189.7 1.90 5.61

1000 131.5 1.31 4.29

710 88.8 0.89 3.40

500 79.3 0.79 2.61

355 52.7 0.53 2.09

250 41.2 0.41 1.67

180 28.1 0.28 1.39

125 25.1 0.25 1.14

90 18.6 0.19 0.96

63 16.2 0.16 0.80

45 11.4 0.11 0.68

38 6.3 0.06 0.62

-38 61.9 0.62

Total 10010.5 100.00

Calculated P80 : 27718 m

A13575 MT TODD GOLD PROJECT - HPGR TESTWORK

VISTA GOLD / KOEPPERN MACHINERY AUSTRALIA PTY LTD

MT TODD 2010 DRILL CORE MASTER COMPOSITE HPGR -32.0mm FEED PSD

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

45.0

50.0

55.0

60.0

65.0

70.0

75.0

80.0

85.0

90.0

95.0

100.0

10 100 1000 10000 100000

% P

AS

SIN

G

SIZE (µm)

SIZE DISTRIBUTION CURVE


(m) (g) (%) % <

Screening 31500 0.0 0.00 100.00

26500 0.0 0.00 100.00

19000 397.6 4.35 95.65

16000 341.4 3.73 91.92

11200 616.6 6.74 85.18

8000 795.2 8.69 76.48

5600 943.5 10.32 66.17

4000 883.5 9.66 56.51

2800 820.8 8.97 47.54

2000 660.0 7.22 40.32

1400 713.0 7.80 32.52

1000 539.4 5.90 26.63

710 392.0 4.29 22.34

500 346.7 3.79 18.55

355 270.6 2.96 15.59

250 216.2 2.36 13.23

180 155.9 1.70 11.52

125 148.6 1.62 9.90

90 109.6 1.20 8.70

63 100.0 1.09 7.61

45 79.8 0.87 6.74

38 22.8 0.25 6.49

-38 593.2 6.49

Total 9146.4 100.00


A13575: HPGR TEST PROGRAMME: MT. TODD PROJECT FEASIBILITY STUDY

VISTA GOLD CORPORATION / KOPPERN MACHINERY AUSTRALIA PTY LTD

MT. TODD 001 GOLD ORE - CENTRE PRODUCT PSD

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

45.0

50.0

55.0

60.0

65.0

70.0

75.0

80.0

85.0

90.0

95.0

100.0

10 100 1000 10000 100000

% P

AS

SIN

G

SIZE (µm)



(m) (g) (%) % <

Screening 31500 0.0 0.00 100.00

26500 144.9 1.42 98.58

19000 1179.0 11.51 87.07

16000 621.2 6.07 81.00

11200 1037.9 10.14 70.87

8000 1069.1 10.44 60.43

5600 1270.9 12.41 48.02

4000 998.2 9.75 38.27

2800 813.9 7.95 30.32

2000 566.4 5.53 24.79

1400 583.4 5.70 19.09

1000 394.3 3.85 15.24

710 274.4 2.68 12.56

500 234.5 2.29 10.27

355 177.1 1.73 8.54

250 139.9 1.37 7.18

180 99.8 0.97 6.20

125 94.4 0.92 5.28

90 66.9 0.65 4.63

63 61.0 0.60 4.03

45 50.8 0.50 3.53

38 11.5 0.11 3.42

-38 350.5 3.42

Total 10240.0 100.00


A13575: HPGR TEST PROGRAMME: MT. TODD PROJECT FEASIBILITY STUDY

VISTA GOLD CORPORATION / KOPPERN MACHINERY AUSTRALIA PTY LTD

MT. TODD 001 GOLD ORE - EDGE PRODUCT PSD

0.0

5.0

10.0

15.0

20.0

25.0

30.0

35.0

40.0

45.0

50.0

55.0

60.0

65.0

70.0

75.0

80.0

85.0

90.0

95.0

100.0

10 100 1000 10000 100000

% P

AS

SIN

G

SIZE (µm)


Sample ID: BULK MMT TODD GO

JO

OLD ORE DRI

OB ID: A135

ILL CORE COM

75

MPOSITE < 331.5 mm – HPGR FEED SAAMPLE

Specif

Roll sp

Feed m

GAP: S

fic pressure:

peed: 14

moisture:

STANDARD 7

3.5 N/

4 rpm

3.00%

7.7 mm

HPG

/mm2

%

GR PRODUCTT – Koppernn HPGR machhine

BOND BALL MILL CLOSED CIRCUIT GRINDABILITY : 125 MICROMETERS

MT. TODD BULK GOLD ORE MASTER COMPOSITE HPGR - CENTRE PRODUCT

CLIENT VISTA GOLD CORPORATION STANDARD HPGR PROD. FEED

PROJECT No A13575 (2010 DRILL CORE MASTER COMPOSITE)

DATE Feb-11

WT OF WT OF

PERIOD REVS WT OF WT OF WT WT NET WT NET WT CIRC'TING FRESH U/SIZE

OF 700 NEW OF OF OF OF LOAD FEED IN FEED

MILL mls FEED O/SIZE U/SIZE U/SIZE U/SIZE ADDED TO TO NEXT

PER REV NEXT CYCLE

(g) (g) (g)* (g)* (g)* (g) (%) CYCLE (g) (g)

1 150 1301.6 1301.6 1025.4 276.2 108.1 0.7205 371 276.2 35.7

2 465 1301.6 276.2 946.0 355.6 319.9 0.6880 266 355.6 45.9

3 474 1301.6 355.6 911.1 390.5 344.6 0.7269 233 390.5 50.4

4 442 1301.6 390.5 929.7 371.9 321.5 0.7273 250 371.9 48.0

5 445 1301.6 371.9 915.0 386.6 338.6 0.7608 237 386.6 49.9

6 423 1301.6 386.6 929.7 371.9 322.0 0.7611 250 371.9 48.07 425 1301.6 371.9 929.7 371.9 323.9 0.7620 250 371.9 48.0

Note : * = Ex grinding mill

PRODUCT IN THE FEED 12.92 (%)

BULK DENSITY 1.8594 (t/m3)

IDEAL POTENTIAL PRODUCT 371.9 (g)

AVERAGE EQUILIBRIUM CIRC LOAD 250 (%)

AVERAGE PRODUCT 0.762 (g/rev)

80 % PASSING FEED SIZE 2485 (µm)

80 % PASSING PRODUCT SIZE 89 (µm)

BOND BALL MILL WORK INDEX ( Kilowatt hours / dry tonne ) : 23.5

SAMPLE IDENTITY

BOND BALL MILL GRINDABILITY TEST FEED AND PRODUCT SIZINGS


A13575

FEED TO PERIOD No. 1 EQUILIBRIUM PRODUCTS

Size Weight Retained Passing Size Weight Retained Passing

(mm) (g) (%) (%) (mm) (g) (%) (%)

2.800 91.3 11.48 88.52

2.000 171.8 21.61 66.91

1.400 132.2 16.63 50.28 0.106 38.1 10.24 89.76

1.000 83.4 10.49 39.79 0.090 33.2 8.93 80.83

0.600 78.7 9.90 29.90 0.075 36.4 9.79 71.04

0.300 79.2 9.96 19.93 0.063 22.8 6.13 64.91

0.212 46.7 5.87 14.06 -0.063 241.4 64.91

0.180 9.1 1.14 12.92

-0.180 102.7 12.92 TOTAL 371.9 100.00

TOTAL 795.1 100.00 P 80 (µm) : 89

F 80 (µm) : 2485

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

90.00

100.00

10 100 1000 10000

% P

AS

SIN

G

SIZE (MICROMETERS)

BOND BALL MILL GRINDABILITY : FEED & PRODUCT SIZEDISTRIBUTION



CLIENT VISTA GOLD CORPORATION RECONSTITUTED HPGR PROD. FEED

PROJECT No A13575 (2010 DRILL CORE MASTER COMPOSITE)

DATE Feb-11

WT OF WT OF




PER REV NEXT CYCLE

(g) (g) (g)* (g)* (g)* (g) (%) CYCLE (g) (g)

1 150 1303.5 1303.5 1037.2 266.3 121.0 0.8066 389 266.3 29.7

2 423 1303.5 266.3 961.5 342.0 312.3 0.7383 281 342.0 38.1

3 455 1303.5 342.0 925.2 378.3 340.2 0.7476 245 378.3 42.2

4 442 1303.5 378.3 903.3 400.2 358.0 0.8100 226 400.2 44.6

5 405 1303.5 400.2 931.1 372.4 327.8 0.8093 250 372.4 41.5

6 409 1303.5 372.4 931.1 372.4 330.9 0.8090 250 372.4 41.5










SAMPLE IDENTITY



A13575



(mm) (g) (%) (%) (mm) (g) (%) (%)

2.800 27.1 4.51 95.49

2.000 106.2 17.67 77.82

1.400 105.6 17.57 60.25 0.106 40.7 10.93 89.07

1.000 85.8 14.28 45.97 0.090 34.4 9.24 79.83

0.600 74.3 12.36 33.61 0.075 36.0 9.67 70.17

0.300 77.3 12.86 20.75 0.063 23.7 6.36 63.80

0.212 47.8 7.95 12.80 -0.063 237.6 63.80

0.180 9.9 1.65 11.15

-0.180 67.0 11.15 TOTAL 372.4 100.00

TOTAL 601.0 100.00 P 80 (µm) : 90

F 80 (µm) : 2099

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

90.00

100.00

10 100 1000 10000

% P

AS

SIN

G

SIZE (MICROMETERS)



Bulk Mt Todd gold ore drill core comp.- Conventional crush product

CLIENT A13575 : VISTA GOLD CORPORATION

PROJECT No A13575 : Mt. Todd project feasibility study

DATE Feb-12

WT OF WT OF




PER REV NEXT CYCLE

(g) (g) (g)* (g)* (g)* (g) (%) CYCLE (g) (g)

1 200 1208.4 1208.4 942.5 265.9 265.9 1.3295 354 265.9 24.9

2 419 1208.4 265.9 901.5 306.9 282.0 0.6731 294 306.9 28.7

3 470 1208.4 306.9 858.8 349.6 320.9 0.6828 246 349.6 32.7

4 458 1208.4 349.6 863.1 345.3 312.6 0.6826 250 345.3 32.3

5 459 1208.4 345.3 863.1 345.3 313.0 0.6820 250 345.3 32.3

6

7

8

9










SAMPLE IDENTITY


Bulk Mt Todd gold ore drill core comp.- Conventional crush productA13575 : VISTA GOLD CORPORATION



(mm) (g) (%) (%) (mm) (g) (%) (%)

2.800 71.4 8.62 91.38 0.125 0.00 100.00

2.000 195.8 23.64 67.73 0.106 25.7 7.44 92.56

1.400 161.5 19.50 48.23 0.090 29.9 8.66 83.90

1.000 99.1 11.97 36.26 0.075 28.4 8.22 75.67

0.600 93.4 11.28 24.98 0.063 24.4 7.07 68.61

0.300 78.0 9.42 15.57 -0.063 236.9 68.61

0.150 42.9 5.18 10.39

0.125 8.6 1.04 9.35 TOTAL 345.3 100.00

-0.125 77.4 9.35

P 80 (µm) : 83TOTAL 828.1 100.00

F 80 (µm) : 2415

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

90.00

100.00

10 100 1000 10000

% P

AS

SIN

G

SIZE (MICROMETERS)



Bulk Mt Todd gold ore drill core comp.- Conventional crush product

CLIENT A13575 : VISTA GOLD CORPORATION

PROJECT No A13575 : Mt. Todd project feasibility study

DATE Feb-12

WT OF WT OF




PER REV NEXT CYCLE

(g) (g) (g)* (g)* (g)* (g) (%) CYCLE (g) (g)

1 200 1208.4 1208.4 942.5 265.9 265.9 1.3295 354 265.9 24.9

2 419 1208.4 265.9 901.5 306.9 282.0 0.6731 294 306.9 28.7

3 470 1208.4 306.9 858.8 349.6 320.9 0.6828 246 349.6 32.7

4 458 1208.4 349.6 863.1 345.3 312.6 0.6826 250 345.3 32.3

5 459 1208.4 345.3 863.1 345.3 313.0 0.6820 250 345.3 32.3

6

7

8

9










SAMPLE IDENTITY


Bulk Mt Todd gold ore drill core comp.- Conventional crush productA13575 : VISTA GOLD CORPORATION



(mm) (g) (%) (%) (mm) (g) (%) (%)

2.800 71.4 8.62 91.38 0.125 0.00 100.00

2.000 195.8 23.64 67.73 0.106 25.7 7.44 92.56

1.400 161.5 19.50 48.23 0.090 29.9 8.66 83.90

1.000 99.1 11.97 36.26 0.075 28.4 8.22 75.67

0.600 93.4 11.28 24.98 0.063 24.4 7.07 68.61

0.300 78.0 9.42 15.57 -0.063 236.9 68.61

0.150 42.9 5.18 10.39

0.125 8.6 1.04 9.35 TOTAL 345.3 100.00

-0.125 77.4 9.35

P 80 (µm) : 83TOTAL 828.1 100.00

F 80 (µm) : 2415

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

90.00

100.00

10 100 1000 10000

% P

AS

SIN

G

SIZE (MICROMETERS)


PROJECT A 13575 MT. TODD PROJECTCLIENT VISTA GOLD CORPORATIONTEST No WH 4612

MT TODD 2010 DRILL CORE MASTER COMPOSITE - HPGR CRUSH PRODUCTGRIND P80 : 90 MICRONSWATER PERTH TAP WATERDATE

ADDITIONS

TIME Solids Water Carbon NaCN Lime Oxygen pH NaCN Au Cu Wt Au Cu Au Cu

(Hours) (g) (g) Haycarb (g) (g) (ppm) (%) (ppm) (ppm) (g) (g/t) (g/t) Total Total

Yao (g) (%) (%)

3000.0 2000.0 1.3 7.8

0 63.1 1.00 1.81 11.0 0.050 0.000 0.0 0.00 0 0 0.00 0.00

1 56.2 0.54 0.00 9.2 10.5 0.023 0.030 41.8 6.84 21 172 52.28 5.08

2 49.3 0.00 0.00 9.1 10.5 0.040 0.010 48.0 6.92 30 198 69.88 5.83

4 41.7 0.00 0.00 9.1 10.5 0.028 0.003 55.3 7.63 33 284 74.90 6.84

6 36.9 0.60 0.00 5.9 10.3 0.020 0.003 60.3 4.80 33 386 74.90 7.61

8 31.9 0.00 0.00 6.4 10.5 0.040 0.003 70.3 5.03 35 414 76.98 8.74

12 27.3 0.00 0.00 6.8 10.4 0.033 0.003 72.3 4.58 36 425 78.79 8.98

24 27.3 0.00 0.00 8.1 10.0 0.008 0.003 78.9 39 888 81.88 10.37

Product Quantity Assay Total Dist'n Assay Total Dist'n

(ppm) (g) (%) (ppm) (g) (%) 1. NaCN Addition : 0.71 (Kg/t)

2. NaCN Consumption : 0.64 (Kg/t)

3000.0 0.16 480 18.12 555 1665000 89.63 3. Lime Consumption : 0.60 (Kg/t)

2000.0 0.003 5 0.19 78.9 157800 8.49 4. Perth Tap Water Used : 1.000 (SG)

1100 41.52 10595 0.57 5. Water weight to leach: 2000.0 (g)

27.3 39.0 1064 40.17 888 24225 1.30 6. Grind Size P 80 : 90 (µm)

7. 63.08 grams of Haycarb Yao activated carbon was added

81.88 10.37 to the slurry at the start of cyanidation.

Total 2649 100.00 1857620 100.00 8. Evaporation losses made up prior to sampling at each period.

Calculated Grade 0.88 619 9. At start of the leach 100 g/t Pb(NO3)2 added.

Assay Grade 1.27/0.75/0.75/0.82/1.02/0.86

* Carbon samples removed at each sampling interval.

SAMPLE

Feb-12

CIL CYANIDATION TIME LEACH TESTWORK : LEAD NITRATE, AIR SPARGE

SOLUTION DATA PREG. CARBON

GOLD & COPPER EXTRACTION CALCULATIONS

Final Carbon (g)

Total Extraction

GOLD COPPER COMMENTS :

Solids (g)

Solution (mls)

Intermed.Carbon *

0

10

20

30

40

50

60

70

80

90

100

0 2 4 6 8 10 12 14 16 18 20 22 24 26

EX

TR

AC

TIO

N

(%)

TIME (Hours)

RATE OF GOLD & COPPER EXTRACTION Au-Total

Cu-Total

PROJECT A 13575 MT. TODD PROJECTCLIENT VISTA GOLD CORPORATIONTEST No WH 4613 DUPLICATE

MT TODD 2010 DRILL CORE MASTER COMPOSITE - HPGR CRUSH PRODUCTGRIND P80 : 90 MICRONSWATER PERTH TAP WATERDATE

ADDITIONS



Yao (g) (%) (%)

3000.0 2000.0 1.4 7.8

0 63.1 1.00 1.98 11.0 0.050 0.000 0.0 0.00 0 0 0.00 0.00

1 54.6 0.54 0.00 9.3 10.5 0.023 0.020 42.1 8.47 21 196 52.79 4.81

2 47.3 0.00 0.00 9.1 10.5 0.043 0.010 48.8 7.30 27 246 64.70 5.61

4 40.0 0.00 0.00 9.1 10.9 0.030 0.003 57.1 7.27 32 340 72.35 6.66

6 34.8 0.64 0.00 6.4 10.4 0.018 0.003 60.6 5.28 33 406 74.67 7.14

8 27.8 0.00 0.00 6.7 10.6 0.038 0.003 64.8 6.97 36 430 78.71 7.60

12 23.5 0.00 0.00 6.8 10.4 0.033 0.003 71.2 4.33 36 430 78.71 8.24

24 23.5 0.00 0.00 7.9 10.2 0.013 0.003 80.4 39 808 81.43 9.60







23.5 39.0 915 35.39 808 18956 0.94 6. Grind Size P 80 : 90 (µm)





Assay Grade 1.27/0.75/0.75/0.82/1.02/0.86


Final Carbon (g)

Total Extraction


Solids (g)

Solution (mls)

Intermed.Carbon *


SAMPLE

Feb-12



0

10

20

30

40

50

60

70

80

90

100

0 2 4 6 8 10 12 14 16 18 20 22 24 26

EX

TR

AC

TIO

N

(%)

TIME (Hours)


Cu-Total

PROJECT A 13575 MT. TODD PROJECTCLIENT VISTA GOLD CORPORATIONTEST No WH 4570

MT TODD 2010 DRILL CORE MASTER COMPOSITE - CONVENTIONAL CRUSH PRODUCTGRIND P80 : 90 MICRONSWATER PERTH TAP WATERDATE

ADDITIONS



Yao (g) (%) (%)

3000.0 2000.0 5.8 8.0

0 63.1 1.00 1.72 11.0 0.050 0.000 0.0 0.00 0 0 0.00 0.00

1 53.7 0.50 0.00 7.0 10.5 0.025 0.030 43.5 9.42 30 200 74.32 4.79

2 47.6 0.00 0.00 7.3 10.4 0.043 0.005 50.3 6.08 32 210 76.51 5.47

4 40.4 0.00 0.00 7.7 10.4 0.030 0.003 61.0 7.20 33 284 78.13 6.66

6 36.9 0.54 0.00 7.6 10.3 0.023 0.003 66.7 3.48 34 390 79.66 7.42

8 32.3 0.00 0.00 8.0 10.4 0.043 0.003 72.9 4.63 35 348 81.07 7.94

12 28.4 0.60 0.00 7.4 10.4 0.020 0.003 77.8 3.90 36 406 82.30 8.50

24 28.4 0.00 0.00 8.4 10.5 0.015 0.003 84.9 36 394 82.30 9.17







28.4 36.0 1021 38.88 394 11178 0.54 6. Grind Size P 80 : 90 (µm)





Assay Grade 1.10 / 1.11 N/A


SAMPLE

Feb-12




Final Carbon (g)

Total Extraction


Solids (g)

Solution (mls)

Intermed.Carbon *

0

10

20

30

40

50

60

70

80

90

100

0 2 4 6 8 10 12 14 16 18 20 22 24 26

EX

TR

AC

TIO

N

(%)

TIME (Hours)


Cu-Total

PROJECT A 13575 MT. TODD PROJECTCLIENT VISTA GOLD CORPORATIONTEST No WH 4571 DUPLICATE

MT TODD 2010 DRILL CORE MASTER COMPOSITE - CONVENTIONAL CRUSH PRODUCTGRIND P80 : 90 MICRONSWATER PERTH TAP WATERDATE

ADDITIONS



Yao (g) (%) (%)

3000.0 2000.0 5.9 8.1

0 63.1 1.00 1.67 11.0 0.050 0.000 0.0 0.00 0 0 0.00 0.00

1 55.5 0.50 0.00 6.6 10.5 0.025 0.005 45.1 7.54 30 164 68.26 4.93

2 50.3 0.00 0.00 7.1 10.4 0.045 0.003 51.7 5.23 33 210 74.06 5.70

4 42.9 0.00 0.00 7.3 10.4 0.030 0.003 62.2 7.44 34 292 75.86 6.93

6 37.9 0.60 0.00 7.8 10.3 0.020 0.003 64.0 5.02 36 358 78.94 7.25

8 31.0 0.00 0.00 8.2 10.4 0.040 0.003 70.3 6.81 36 336 78.94 7.82

12 25.7 0.54 0.00 7.4 10.4 0.023 0.003 78.7 5.35 36 384 78.94 8.72

24 25.7 0.00 0.00 7.9 10.3 0.015 0.003 86.6 39 444 81.70 9.57







25.7 39.0 1002 35.95 444 11406 0.56 6. Grind Size P 80 : 90 (µm)





Assay Grade 1.10 / 1.11 N/A


Final Carbon (g)

Total Extraction


Solids (g)

Solution (mls)

Intermed.Carbon *


SAMPLE

Feb-12



0

10

20

30

40

50

60

70

80

90

100

0 2 4 6 8 10 12 14 16 18 20 22 24 26

EX

TR

AC

TIO

N

(%)

TIME (Hours)


Cu-Total

Documents

TABLE SO /Air Cyanide Detoxification Test D5 AMMTEC FS... · Sample: WH4270 Operating Conditions ... Soln (S.G.) 0.999 CNp determined by Picric Acid method (CNp is equivalent to CN