LongLong--Term Monitoring Data Term Monitoring Data from the Britannia Mine, BCfrom the Britannia Mine, BC

Kelly Sexsmith, Danette Schwab and Kelly Sexsmith, Danette Schwab and Stephen Day, SRK Consulting Stephen Day, SRK Consulting

Rob Rob McCandlessMcCandless, Environment Canada, Environment Canada

AcknowledgmentsAcknowledgments

BCWLAP BCWLAP

Gerry O’HaraGerry O’Hara-- GolderGolder Associates Associates

Peter Healey Peter Healey –– SRK Consulting SRK Consulting

Pat Bryan Pat Bryan –– Associate ConsultantAssociate Consultant

Terry Johnson Terry Johnson -- Mine ManagerMine Manager

Presentation OutlinePresentation Outline

GeologyGeology

Historical Water QualityHistorical Water Quality

PrecipitatesPrecipitates

Comparisons with Similar SitesComparisons with Similar Sites

2002 Plug Test2002 Plug Test

Post Test Water QualityPost Test Water Quality

ConclusionsConclusions

Britannia Mine Geology Britannia Mine Geology -- 11

Britannia Mine Geology Britannia Mine Geology -- 22

4100

2200

Jane

Jane

Fairview Zinc

Fairview Veins

East Bluff

Bluff

No. 4

040

Britannia Mine Geology Britannia Mine Geology –– 33

VolcanicVolcanic--associated associated massive sulphide depositmassive sulphide depositdacitesdacites > > andesitesandesitesclasticsclastics and tuffsand tuffs

Ore minerals Ore minerals pyrite>>chalcopyrite> pyrite>>chalcopyrite>

sphaleritesphalerite>>galena, >>galena, nono pyrrhotitepyrrhotite..

Gangue mineralsGangue mineralsquartz, chlorite/quartz, chlorite/biotitebiotite, ,

anhydrite, siderite, bariteanhydrite, siderite, bariteJane Basin, looking SW

10

100

1000

10000

’29 ’39 ’49 ’59 ’69 ’79 ’89 ’99

Co

pp

er (

mg

/L) Dissolved Cu

Total Cu

Historical Copper Data Historical Copper Data –– 2200 Level2200 Level

2200 2200 -- Seasonal Flows and Seasonal Flows and Copper Concentrations Copper Concentrations

(1945 to 1952)(1945 to 1952)

0

500

1000

1500

2000

2500

3000

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Flo

w (

m3/

day)

, Cu

(mg

/L)

CopperFlow

Historical Copper Data Historical Copper Data -- 4100 Level4100 Level

0

10

20

30

40

50

60

70

72 77 82 87 92 97 02

Cop

per

(mg/

L)

Dissolved CuTotal Cu

Britannia Mine Water QualityBritannia Mine Water Quality

970497045521214.24.24.54.518180.090.092626152815283.83.841004100

278327831.51.529293.63.6313159590.190.194242108810883.13.122002200

ZnZnMnMnFeFeCuCuCdCdAlAlSO4SO4pHpH

Av. Av. flow flow m3/ m3/ dayday

Dist. Dist. from from mine, mine, kmkm

Averages, preAverages, pre--2001 chemistry2001 chemistryStnStn..

Data compilation courtesy BC MWLAP and SRK

* Concentrations are in mg/L

Britannia Mine GeochemistryBritannia Mine Geochemistry

Differences between 4100 Differences between 4100 and 2200 due to dilution of and 2200 due to dilution of some unknown mine water.some unknown mine water.

pH > 3 (at least since 1972)pH > 3 (at least since 1972)�� Fe and Al precipitation may act Fe and Al precipitation may act

as buffer.as buffer.

�� ?Lack of ?Lack of pyrrhotitepyrrhotite

During mining, with fresh air During mining, with fresh air and fresh mineral surfaces, and fresh mineral surfaces, 2200 Cu was 1500+ mg/l.2200 Cu was 1500+ mg/l.

Jane Creek before Dec ’01

Geochemistry of the 4150 Geochemistry of the 4150 SludgesSludges

Whole rockWhole rock: : 57 % Fe57 % Fe22OO33

2 % Al2 % Al22OO33

38 % loss on ignition38 % loss on ignition

ICP metalsICP metals (ppm, dry wt)(ppm, dry wt)

Cu Cu –– 4382, 4382, Zn Zn –– 360360CdCd –– <0.8, <0.8, PbPb –– 181 181 Fe Fe –– 107,000107,000

Iron hydroxide sludge, 4150 level

Britannia compared to othersBritannia compared to othersTulsequah Chief:Tulsequah Chief:

pH pH -- 3.0 Cu 3.0 Cu -- 33.533.5Fe Fe -- 34 Al 34 Al -- 2222Zn Zn -- 63 SO63 SO44 -- 997997

(after SRK Consulting, 1992)(after SRK Consulting, 1992)

Anyox:Anyox:pH pH -- 2.8 Cu 2.8 Cu -- 2.32.3Fe Fe -- 275 Al 275 Al -- 4848Zn Zn -- 5 SO5 SO44 –– 35003500

(Environment Canada data to 2000)(Environment Canada data to 2000)

* Concentrations in mg/L* Concentrations in mg/LAnyox adit drainage

Release of Water During 2002 Plug Test

4100 L

2700 L

4100 Portal

4100 Plug

Mineral Creek

Britannia Creek

Flooded Mine Workings

HoweSound

Britannia Beach

#10 Shaft

Bluff Victoria Shaft

Mine WorkingsFlooded during Plug Test

Jane Basin

2200 L

2200 Plug

0

50

100

150

200

250

30013

-Mar

10-A

pr

08-M

ay

05-J

un

03-J

ul

31-J

ul

28-A

ug

25-S

ep

23-O

ct

Wat

er L

evel

(m

)

April 25

June 19

Aug 16Draindowncomplete

Plug TestsPlug Tests

pHpH

pre-plug avg.

2.5

3

3.5

4

4.5

5

2-Apr-02

30-Apr-02

28-May-0

225-Ju

n-02

23-Jul-02

20-Aug

-0217-S

ep-02

15-Oct-02

12-Nov-02

10-Dec-02

7-Jan-03

4-Feb-0

34-M

ar-031-A

pr-0329-A

pr-0327-M

ay-03

24-Jun-0

322-Ju

l-0319-A

ug-03

16-Sep

-0314-O

ct-03p

H

Draindowncomplete

0

500

1000

1500

2000

2500

3000

2-Apr-02

30-Apr-02

28-May-0

2

25-Jun-0

2

23-Jul-02

20-Aug

-0217-S

ep-02

15-Oct-02

12-Nov-02

10-Dec-02

7-Jan-03

4-Feb-0

3

4-Mar-03

1-Apr-03

29-Apr-03

27-May-0

3

24-Jun-0

3

22-Jul-03

19-Aug

-03

16-Sep

-03

14-Oct-03

Sulp

hat

e (m

g/L

)

Pre-PlugAverage

0

10

20

30

40

50

60

70

2-Apr-02

28-May-02

23-Jul-02

17-Sep-02

12-Nov-02

7-Jan-03

4-Mar-03

29-Apr-03

24-Jun-03

19-Aug-03

14-Oct-03

Copper

(m

g/L

)

Pre-PlugAverage

Sulphate and CopperSulphate and Copper

Draindowncomplete

IronIron

0.1

1

10

100

1000

2-Apr-02

30-Apr-02

28-May-0

225-Ju

n-02

23-Jul-02

20-Aug

-0217-S

ep-02

15-Oct-02

12-Nov-02

10-Dec-02

7-Jan-03

4-Feb-0

34-M

ar-031-A

pr-0329-A

pr-0327-M

ay-03

24-Jun-0

322-Ju

l-0319-A

ug-03

16-Sep

-0314-O

ct-03

Iro

n (

mg

/L)

Pre-PlugAverage

Draindowncomplete

Comparison of PreComparison of Pre--Plug and Plug and PostPost--Plug Test ConcentrationsPlug Test Concentrations

1427

1364

130013251350137514001425145014751500

SO4 (wt. avg) SO4 (2003)

30

22.5

27.4

18.715

20

25

30

35

Al Al Cu Cu

10.6

1.2

4.1 4.4

0

3

6

9

12

Fe Fe Mn Mn

3.6 4.0

0

2

4

6

8

pH (wt avg) pH (2003)

4100 L

2700 L

Permanently Flooded Mine Workings

Bluff

Mine WorkingsFlooded during Plug Test

Jane Basin

2200 L

2200 Plug

Victoria Shaft

ConclusionsConclusionsFlooded mine water had lower pH and higher Flooded mine water had lower pH and higher than average sulfate and metal concentrations than average sulfate and metal concentrations compared to precompared to pre--plug test values, consistent plug test values, consistent with the leaching of stored acidic salts with the leaching of stored acidic salts

Higher than average sulphate and metal Higher than average sulphate and metal concentrations persisted for 2 to 3 months concentrations persisted for 2 to 3 months following the testfollowing the test

Concentrations of sulphate, aluminum, copper Concentrations of sulphate, aluminum, copper and iron were below average 4 to 10 months and iron were below average 4 to 10 months after the test, indicating effects of flooding were after the test, indicating effects of flooding were relatively short durationrelatively short duration