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Royal Oak Mines Inc. - Yellowknife Division The Giant Mine

Water License HlL3-0043

Submission in Support of an Application cy Royal Oak Mines Inc. to have the N.W.T, Water Board Renew the Water Use License for the Giant Mine

September :1,1992 -1.~-~ ;. ~ •.:..,.._·~ -•·-• •• ·~ 'C

1.0 IDtrocluctioD This submission is in support of an application made by Royal Oak Mines Inc. on July 27,1992 to renew water use license# NlL3-0043. This license was isaued to Giant Yellowknife Mines Limited by the Northwest Territories Water Board on April Ol,1987 for the purpose of licensing the industrial use of water in mining, milling and associated uses at the Giant mine in Yellowknife. This license is scheduled to expire on April 30,1993.

2.0 Back9roW1d The first gold discovery in the Yellowknife area came nearly a century ago in 1896, when a prospector named Arthur Blakeney, on his way to the Yukon and the Klondike gold rush, found some rich samples not far north of where the Giant mine stands today. Blakeney, perhaps unwisely, continued on his way L O the Yukon; what happened to him no one seems to know.

It wasn't until 1934 that the firs~ ma Jcr Ye~lowknife discoveries were made. By the next year, the shores o: Yellowknife Bay were dotted with the tents and hastil y ~r.rown up cabins of prospectors eager to get in on the action. Amo~ ~ them was C. J . Baker, better known as Yellowknife Johnny. In 1934 ne and h:s partner, Hugh Muir made an exciting find - the Burwash ?-'..l.ne proper~i·, but unfortunately this property proved to be only a sma:l depos:~ . The two of them persevered and later staked the 21 cr~gina: Gian~ claims in July of 193S.

In August of 1937 Giant Yellowknife Mines was incorporated, but Baker's luck didn't improve for the next fe.. years of investigation and drilling on the property offered little encouragement. The property wasn't explored again unti~ 1941, when Donald w. Cameron, a veteran prospector re-examined a prc~ ir.enc quartz outcrop near the southeast boundary of the property. !-: was whil e conducting the task c! mapping the structurally complex geology c! the area that a consulting geologist, Dr. A.S. Dadsc~. specul ated that there may be a major shear zone underlying th~ area extending through the property to the east c f the Wes~ Ba:/ Fa~::.:., 1mo.. n as the Baker Creek Valley . An aggressive diamond dri:::. program conducted to test this theory resulted in a spectacular discovery which was far richer than anyone had anticipated. A staking rush ensued and plans were quickly adapted to bring this deposit, aptly ca lled the Giant Mine, into production. By May of 1948 the first gold bar was poured, and since then more than 7,000,000 ounces have oeen produced, valued at more than $900,000,000.

During the 1960•s, two adjacent properties , the Lolor Mine, owned by Lolo:- Mines Limited and the Akaitcho Mine ( later called "Supercrest") , owned by Akaitcho Yellowknife Gold Mines Limited were developed. Through the exchange c: snares fer aevelopment dollars, Giant Yellowknife Mines acquired management control of Lolor Mines Limited, Akaitcho Yellowknife Gol d Mines Limited and the development company Supercrest Mines Limited. Toe Lalor Mine ceased production -- in 1948, while production at Supe=crest has bee~ sporadic since the mid 1980's. The Giant mine has been producing gold continuously for over 40 years and has accounted for SO\ of the 14 million ounces of gold produced in the Yellowknife area since its discovery in 1934.

The discovery and development of the Giant Mine made the town of Yellowknife a familiar name the world over, and contributed to the jobs and the resources which supported and encouraged the growth that the town has encountered over the past 43 years.

In 1986, Giant Resources of Australia acquired the controlling interest in Giant Yellowknife Mines Limited from Falconbridge Nickel Mines Limited. Subsequently in November of 1990 this controlling interest was sold to Royal Oak Resources Ltd. In July of 1991, Royal Oak Resources Ltd., Giant Yellowknife Mines Limited, Pamour Inc., Pamorex Minerals Inc, and Akaitcho Yellowknife Gold Mines Limited were amalgamated into a new corporate entity called Royal Oak Mines Inc.

3.0 Process Description The Giant Mine is operated as prima:-~.: y a~ underground mine although in past years ore has been recovere~ from a series of small open pits. The ore body has a strike lengtn of over 16,000 feet and is accessed through three shafts and~~~ ramp systems. Currently, only the "C" shaft is active and the centr£-l and northern portion of the ore body which are served from "C" Shaft are a l so accessed by the main ramp system to the base of the ore body. The southern portion is accessed from the bottom of the Al open pit by the "A~ ramp. Open pit mining operations were shut down in 1990. Underground mining is principally by mechanized cut and fil. !. technique. The surface layout of the minesite is shown in figure 3.1. A cross sectional view of the underground is shown in figure 3.2.

Gold present in the Giant ore is assc =iated with the arsenic bearing sulphide mineral, arsenopyrite. The ore is refractory, meaning that the arsenopyrite mineral structure must be broken down and oxidized t o allow the effective recovery :::: tne contained gold. The arsenopyrite and other sulphide minera.L s ar<.? first concentrated by flotation. Tne flotation concentrates are tne~ roasted and leached in cyanide to achieve an overall golc recovery of 87.5\. The milling capacity of the ore processing plan~ at the Giant Mine is 1,300 tons per day with roasting capacity of 22C tons per day.

A simplified mill flowsheet is shown 1n figure 3.3.

Run of mine ore is crushed underground in a primary jaw crusher and then hoisted to surface through ":·· sna!t. to a surface coarse ore storage bin. Additional ore is truck hauled to surface through several underground ramp systems. The combined ore is then crushed and screened at a three stage surfac~ crusnin; plant with the minus 3/8th inch material being conveyed into tne mill storage bins. Ore is drawn off the mill storage bine into two parallel primary grinding lines each consisting of an 8' diameter x 10' ball mill - ~- ,...._. working in closed circuit with a spiral classifier. Water is added to the ore a-:: the feed end o: tne two ba_l mills. The spiral classifier is a particle sizing device using th~ specific gravity of 0 the ground ore particles to separate fine particles from coarae particle&. The coarse particles are returned to the primary ball mill to be ground again while the fine particles overflow the spiral classifier. The combined overflows from both spiral classifiers is then screened to remove wood chips and other debris that may interfere with later process equipment.

The screened classifier overflow i s then subj ected to a processing step called flotation where under controlled conditions the sulphide minerals are separated from the ground ore slurry. The sulphide minerals contained in the Giant ore are principally areenopyrite and pyrite. The surface of these sulphide minerals is coated with copper sulphate which is added at the feed end of the ball mill. The copper ions selectively coat the sulphide mineral surfaces. A chemical flotation collector called xanthate i s added at the classifier overflows and attaches itself to the coated sulphide minerals. The xanthate has a high affinity for air which is bubbled through the flotation cells. A commercial frothing agent. called Dowfroth is added to the slurry at the chip screen and provides a strong stable air froth when air is bubbled through the slurry. The xanthate and the attached sulphide minerals attac:: tnemselves to these air bubbles and float t o the surface c : tn~ f l otation cell.. At the surface of the flotation cell, this s ulphide mineral rich froth is skirrwned into a concentrate launde:- an= collected for further processing.

The flotation circuit is broken into two sections set in aeries. The first section is called the rougher circuit. Material that did not float off in the rougher circuit is reground in two parallel regrind circuits each consisting of a ball mili worki~g in closed circuit with a set of cyclone sizing devices. The fine particles contained in the cyclone overflow from these two regrind circuits are combined and subjected to a second flotatio~ circui~ called the scavenger circuit. Additional copper sulphate, xanthate and dowfroth are added to the regrind circuits.

The f lotatio:, circuit is esse:1-. :..al~:,· .,_ pre-concentrating step enabling Royal Oak t o recover 9$~ c : tne gclc contained in the 1300 tons per day of ore milled in a sulpniae mineral concentrate that weighs 200 tons per day. The remaining llOC tons per day containing 5% of the gold are re;ected to the tailin9s impoundment area as what are called flotation tailings.

The flotation concentrates from bot:1 the rougher and scavenger circuits are combined and dewatered in a circuit using a dewatering cyclone and a thickener. The wate:- i s returned to the grinding circuit as a recycle strearr.. The principa: gold bearing mineral contained in this flotation concentrate is arsenopyrite, which is an arsenic - iron sulphide. The gold is interstitially locked inside the arsenopyrite mineral matrix making .:.~ resistant to recovery without first destroying the arsenopyrite mineral structure, hence the term refractory gold. The breakdown c! the areenopyrite mineral matrix is accomplished in a two stage !luid bed roaster at high temperature. The flotation concentrate is thickened to a density of 75% solids and then sprayed into tne firs~ stage of the roaster. The sulphur contained both in the pyrite and arsenopyrite is oxidized through contact with air blown in through the tuyeres at the bottom of the roaster generating the heat which fuels the process. The atmosphere inside the first stage roaster is kept as close as possible to a reducing atmosphere (no residual oxygen). The arsenic contained in the arsenopyrite is oxidized and fumed off as gaeeoue arsenic trioxide. The remaining sulphide mineral is transferred into the second stage of the roaster and again oxidized at elevated temperature driving off the sulphur contained in the areenopyrite and pyrite as gaseous sulphur dioxide.

The off gasses from the two stages of roasting are combined, cycloned to remove coarse entrained dust particles and then passed through an electrostatic precipitator. This electrostatic precipitator uses electrical energy to charge the fine particles of entrained dust contained in the roaster off gas and then to remove these particles from the gas stream by collecting them on oppositely charged rods. The dust collected in these precipitators is slurried with water and processed to recover the contained gold.

The tail gas from the precipitator ~s cooled by mixing the off gas with large volumes of outside ai::. J>.s the gas cools the arsenic trioxide condenses from the gas as a solid. This arsenic trioxide dust is then filtered from the gas s~ream in a baghouse style dust collector. The remaining gas stream which is a dilute mixture of sulphur dioxide and air passes through the baghouse fabric dust collection bags and is exhausted tc the atmosphere through a 150 foot high stack. The arsenic trioxide dusts collected in the baghouse are pneumatically conveyed into specially prepared vaults located underground. Theae vaults are isolated from the mine workings and are built in the permafrost so that the arsenic trioxide dust will freeze . These storage vaults are excavated in competent waste rock, sealed with concrete bulkheads and then refrozen using cold winter air.

The material left after roasting the flotation concentrate is called calcine. Roaster calcines are the gold cearing remains of the pyrite and arsenopyrite after the majorit.y :. : tne s1.aphur and arsenic have ceen driver. c!f as a gas. These ca_:ines consist of iron oxides, principally nematite and magnetite. Tne roaster calcines are water quenched and then ground in two ba:l mills which work in closed circuit with cyclones. The ground calcines are water washed in a thickener to remove excess acidic water and t o increase the slurry density for subesquent gold leaching. The was~ thickener overflow• are rejected to the tailing impoundtne~t area. The regrind breaks down the size of the iron oxides contained in the roaster calcine exposing the contained gold for later recovery using lime and aodium cyanide.

The alkalinity of the washed calcine ~s then pH adjusted to 11.0 using lime. Sodium cyanide both :..:-. tne form of recycled barren solution, minewater and fresh cyaniae solution is added to the calcine. The contained gold is then leached from the calcine by the cyanide in a two stage agitated leach circuit. The gold is dissolved into solution as a gold cyanide complex. After the first stage of leaching, the calcine is partially dewatered in a thickener. The dewatering solution contains dissolved gold and is thus recovered for subsequent recovery. Fresh cyanide solut1.on is added to the J /() Crushing l d _Grinding l ~ ~ Flotation __... Tailings ----. J Sulphld• Tempering Conc•ntral• Air Stack J Fluo-solid Electrostatic Precipilatior 1 Bag house

cs- e~J Dusi Carbon In Pulp n L!~~~ku· Leaching Plant -Tailings --- ~· Roaster! □J ------, • Calcine ' I Underground I Storage - - Carbo: Strip - •:

j Tailings Ponds V ( Cyanidalion ) Residue lo Tailings --- ! Solutbn Effluent Plant

Precipltation-earren Bleed 10 Tailings-...;.....,. ~1111111111111111!111111111111 [J I J I J I • +Carbon Columns [®] Refining• ------i DD ~ ~ Bullion Creek

Figure 3.3 Giant Mine - Simplified Mill Flow Sheet ., I I : ' thickened calcine which in turn is leached in a second stage of agitated leaching. Again the slurry from the second stage leach is dewatered in a thickener with the solution recovered for subsequent processing. The thickened slurry is then filtered to remove all gold bearing solutions which are again recovered for subaequant processing. The filtered solids are called the calcine residue and are rejected to the tailings impoundment area.

All of the gold bearing solutions (pregnant solution) recovered from the calcine leach circuit are combined and then filtered in a leaf clarifier using canvas bags coated with diatomaceous earth. The clean pregnant solution is then deoxygenated in a merrill crowe tower. Zinc dust is added to the deoxygenated solution allowing the gold cyanide complex contained in solution t o •·precipitate" onto the zinc dust ( actually a plating reaction) . The zinc dust is then filtered from the solution using a press filter. Lead nitrate is added to the pregnant solution a~ the clari.fier to enhance the precipitation of gold onto the zinc dust. br complexing competing ionic species.

Tne gold bearing filtered zinc dus~ ls periodically removed from the press and melted to form a gold dore bullio:-.. The solution that passes through the presses is aeratea and returned to the circuit as barren solution. The barren soh.1tlc:-: is re:=ycled to the leach circuit to make effective use of the contained unreacted cyanide. A portion of the barren solution is bled to the tailings impoundment t o control the buildup of impurities tha-: l.nhibit the cyanide dissolution of gold.

A more detailed mill process flowsheet is presented in figure 3.4. The location of all reagent additio:1 points are included on this drawing.

,.o Tailing Disposal and Effluent Treatment

The final waste product from the ~:::i'"~ opera-:ions is referred to as mi~l tailings.. The solids the-: ma,:e ~;: -:ne :r.ill tailings come frore tnree primarr sources:

- Flotation Circuit Tailings 1100 t.0:1s pe:- da:·

- Calcine Residue l9C tons per day

- Electrostatic Precipitator Dust Residue :c· tons per ciay

In addition the following solutio:-: streams are combined with the solid tailings for disposal:

- Barren Solution Bleed

- Roaster Calcine Wash Thickener Overflows

Sewage from the mine townsite and mine b~ildings

' - Excess Minewater not used in the Mi.lling Process All of these waste stream are combined in the mill and then pumped through a pipeline to the tailings impoundment area. The Tailings ImpoundJllent area at the Giant mine consists of four solid storage ponds, one sludge settling pond and a polishing pond. The location of these facilities is shown in figure 4.1.

These tailings ponds were created by constructing a series of low permeability containment dams in a natural valley or topographic depression. The darns are constructed of rockfill with a low permeability compacted clay till core. This clay till core serves as a barrier to keep the tailings solution inside the impoundment area. A rockfill shell constructed on both the upstream and downstream side of the clay till core holds the structure in place. There is a filter zone constructed of sized crushed rockfill installed between the compacted clay till core and rockshell on the upstream face of each of these dams to prevent wave action erosion of the clay till core. These structures are constructed on clean bedrock surfaces that have been grouted to reduce potential seepage paths below the base of the dams. In circumstances where oedrock was too deep the dam structures have been construccej c ~ ~ayers of sand and gravel where care has been taken to main~a:~ ~r.~ unaerlying ground in a frozen condition.

The tailings dams are engineered str~=tures designed on the basis of geotechnical information specific ~-- eac~ structure. Periodic inspections of these dams by a competer.t geotechnical engineer has taken place on a regular basis.

The currently active tailings impoundment fac~lity is the Northwest Pond first put into service in late 1987 . The original tailings impoundment facility consists of the North and central Ponds which in reality are a single pond separated by a causeway. The South Pond was constructed in the early 1980·s and ~snow used as an emergency dumping area for mill tailings wnenever the pipeline to the Northwest pond is out of service. A large pcrtion of the tailings contained in the North pond were extractec and reprocessed in the summer o: 196S, 1989 and 1990 wner. ~ne :a~l inqs Retreatment Plant was in operatiot, . The tailings extracte= :ro~ tne North pond were redeposited in the Northwest Tailings Pond following processing at the Tailings Retreatment Plant. Poer economics have resulted in the suspension of operations at this plant and at current conditions it remains uneconomic to reprocess taili~gs at the Giant mine.

The Northwest Tailings pond will continue to oe the active tailings impoundment area for the near futur~. The continued raising of the containment dikes for this impou:1cimer.:. is an option that will provide additional storage volume. Geotechnical investigations will determine the extent to which this expansion would be feasible.

As the Northwest Tailings pond reacnee capacity, the North pond will be established as the active tailings disposal facility. The excavation of tailings from this area fc~ ~he Tailings Retreatment Plant creates a logical void to be =~lied ~i~~ future mill tailings. To accomodate the use of this area Tailings dam# 2 would be rebuilt in subsequent lifts to provide adequa~e s~orage volume. Latitude Approximately 62° North

Yellowkni River

TAILINGS PONDS ......

... -­.-...... Yellowknlfe ... ' Bay .. .-...... AIL 610' ...... ·- ...... '!" ...... ---:­ r-...... - 1 Mile ......

. __F igure 4.1 The Giant Mine - Location of Tailing Impoundment Facilities Royal Oak Mines Inc. will continue to work with its geotechnical consultant to both monitor the existing tailings impoundment facilities and to plan for future disposal needs. We do not anticipate having to construct any new tailings disposal facilities outside of the Northwest and North ponds during the next five year period.

The technology for successfully treating cyanide bearing waste from gold milling operations is relatively new and is thus still undergoing change. In 1974 Environment Canada exempted gold mining operations in Canada using the cyani de leach process from having to comply with the Metal Mining Efflue~t Regulations primarily due to the abscence of a demonstrated technology to deal with this problem, In 1976, Giant Mine in conjunction with Envi ronment Canada under took a pilot plant designed to demonstrate the applicability of alkaline chlorination to the treatment cf cyanide bearing gold mill tailings. Alkaline Chlorination was thought to be the best available technology for the treatment of gold mill tailings at this time. As a result of this research, in 198: at a cost of over S2 million, Giant Yellowknife Mines Limited cons-:.ructed a~d operated the first alkaline chlorination-ferric sulph.a-:.e efflue~-:. treatment plant to be operated at a gold mine in North America.

As is the case with most new technologies, opera-:.ing experience with the plant brought up new areas o! cancer~. Whi l e the process was very effective at reducing concentrations of cyanide, arsenic, total copper, nickel, zinc and lead, the residua~ levels of chlorine left in the treated effluent presented new enviroru:,ental problems. In 1989/90 at a cost of Sl million, ne~ technological advances were incorporated into this treatment plant by converting from the use of chlorine to hydrogen peroxide for the oxidation of metal cyanide complexes. At the same time the leve: c f instrumentation within the treatment plant was increased t o a~~omate continous operation of the circuit during sutm1er months. The environmental problems relating to residual chlorine in the treated efflue~~ were thus eliminated completely.

The tailings impoundment areas sen·e a s set~ling basins where the solid tailings settle by gravity a!l owing the contained water to rise. Each summer the solution tha~ pools o~ top of the tailings solids is pumped to an effluent treatment plant located to the north of the North pond. At a controlled rate of 3800 IGPM the tailings pond water is treated through two paralle l circuits. Copper Sulphate is added to the effluent treatmer.~ plan~ feed stream to provide sufficient copper in solution to ca~alyze the subsequent oxidation of cyanide complexes. The pH of the water is adj usted to 9.2 using lime and then the water is treated with hydrogen peroxide. The hydrogen peroxide oxidizes the cyanide complexes contained in the tailings water converting them t o cyanate which in turn breaks down to carbon dioxide and nitroger. . T::e efficiency of this cyanide oxidation reaction is 98\.

Following treatment of the tailings water with hydrogen peroxide, ferric sulphate is added drivi r.= the pH down to 7.0 while precipitating the contained arsenic as ferric arsenate. The ferric arsenate precipitate is relativel:,· insoluble 1.n water and thus _..- -.. ---

provides a ■ atisfactory method of complexing and removing soluble arsenic from the tailings pond solution. The efficiency of this process in removing soluble arsenic from the tailings solution is 94%.

The pH of the treated solution is then raised to pH 8.5 thereby precipitating the other heavy metals complexed with cyanide such as cu, Ni, Pb and Zn onto the remaining ferric sulphate, effectively removing them from solution:

Cu Removal 95\ Pb Removal 80\ Ni Removal 70\ Zn Removal 95\

The treated water from the effluen~ treatment plant is discharged into the sludge settling pond where the ferric arsenate and other iron complexed metal sludges are allowed t c settle. The clear solution is filtered through a rockfi:: causeway into a secondary polishing pond. Water from the polish~ng pc~d is taken through a series of columns containing activated carbc~. The activated carbon in a non selective manner adsorbs residual metal cyanide complexes such as gold, copper, etc onto the carbon from the polishing pond water. After passing through th€ carbo:: c o lumns the water is released into Baker Creek which flows into Yellowknife Bay.

The cost of effluent treatment i s approximately $2.28 per 1000 Imperial gallons providing the company with a strong financial incentive to conserve water usage whereve= possible. In the time period between the beginning of 1987 and the end of 1991 an average of 317.8 Million Imperial gallons of water were treated each year at a cost in excess of S700,000 per annu::-.. Ir. thits same time period the amount of contaminants removed at the e!!luer.~ ~reatment plant have averaged:

Cyanide 40 tons per yea!' Arseni= 18 tons per yea= copper 21 tons per year Lead 0.6 tons per year Nickel 2 tons per year Zinc 2 tons per year

In 1988 the use of gaseous chlorine ~o oxidize cyanide contained in the tailings pond solution was discontinue::i and replaced with hydrogen peroxide. This conversio:: eliminated a long standing problem experienced with residua~ chlorine levels left in the treated effluent.

In 1990 the capacity of the effluer.~ treatment p lant was increased by 100\ to offaet the increased volumes resulting from the Tailings Retreatment Plant and to compensate fo::- the volumes of tailings solution not treated in the summer= ~ 1988. 5.0 Application for Renewal of Water License HlLl-0O43 Royal Oak Mines Inc. presents this submission in aupport of its application to have the NWT Water Board renew the Water Use Licenee for it's Yellowknife Division, the Giant Mine. This mine has been in continuous operation in Yellowknife since 1948. Water Uae License NlLJ-0043 was first issued to the mine by the NWT Water Board for a five year period beginning in 1982 and was subsequently renewed for a second five year period in 1987 . The current license expires on April 30,1993.

Royal Oak Mines respectfully requests that the current license be renewed for a further 10 year period through April 30, 2003. Royal Oak Mines Inc. does not have any plans t o make any significant changes in either the mining/milling rate or processing techniques employed at the Giant Mine throug~ the foreseeable future. Consequently we respectfully request .. renewal of the current license with no change in the condition~ pertaining to water use at the Giant Mine.

Name of Applicant

Royal Oak Mines Inc. Yellowknife Division, The Gia~= Xin& Postal Bag 3000 Yellowknife, NWT XlA 2M2

5.2 Quantity of Water Consumed The maximum allowable use of wate.::- tc::- industrial purposes is stipulated in the current water use- l.lcense at l, 950,000 cubic meters annually. The license defines ~his maximum allowable volume as the sum of the water drawn from Great Slave Lake at the mine pumphouse for industrial purposes p~us ~:: aroundwater pumped from the underground mine.

The water consumed for industrial p:.:rposes oy the mine is drawn from a pumphouse at the minesite located =~ t~e shore of Great Slave Lake on Back Bay. This water is pumpe:: t::r::::.::::-, a d1.s-;ribution loop to the mine facilities and is the principa_ s o:.:rce ~=industrial water used for all mine, milling and related act~·:.:.ties. A water meter is used to monitor the actual consumption c : freshwater by the mine which in turn is reported monthly to the NW7 wa-ce.::- Board.

The volume of groundwater pumped c~t o: the mine is calculated by subtracting the volume of water pumped o~t cf the underground mine from the volume o: freshwater pumped into tne m1ne. Both of these volumes are measured by flowmeters a::j are reported monthly to the NWT. A factor is used to account fc.::- th~ recycle of water from the Northwest Tailings impoundment that ~s net returned directly to the pond via the Supercrest mine pump5 .

A record of these volumes from Janua.::-:: 19E., tnrough June 1992 is shown in Table 5. 2.:. The same data :.. s presented graphically in Figure 5 . 2 • l. iable 5.2.1. - Water License N1L3-0043 - Monthlv Water Useage log -.. Page I Df 2

Pu■ped Treated A Shaft Fro11 KineNater Co•~ressor &round Date Carbon Sreat Discharqed Cooling Water Water Ko/Yr Column Slave To Balcer llate; Fro• City Seepage Discharge Lake Creek Discharged Of VK Fro• U/6 K3 K3 113 H3 N3 N3 43-1 43-4 43-i 43-6

01\87 0 94858 0 0 13124 02\87 0 96839 0 (I 10901 03\87 0 76472 0 (l 11999 04\87 0 59274 0 (I 12035 05\87 (J 68856 0 0 12518 40b6/+ 06\87 78624 90126 0 0 12502 42089 07\87 387255 87711 0 0 1747b 43350 08\87 257429 10091 0 0 0 43586 09\87 284557 82955 0 0 16749 42735 10\87 164942 79111 (I 0 2oq05 4211,9 11\87 15135b 79112 0 0 224b6 38601 12\87 0 79115 0 (l 21331 39919 Total 1324163 904520 0 (i 172085 333114

01\88 0 79120 0 (l 205b7 41685 02\88 0 85096 0 0 23572 39857 03\88 0 106317 0 0 22095 37117 -., 04\88 0 93348 0 0 %79 40711 05\88 0 125lbb 0 (J 25863 72983 0b\88 (j 112582 0 0 947S 89256 07\88 0 113715 0 0 11984 139586 08\88 0 122943 0 0 2339; 133906 09\88 0 110702 0 0 22773 107550 10\88 0 109653 0 0 21ii:5 100152 11\88 0 174713 0 0 22i43 83998 12\B8 0 141881 0 (l 2341+3 90612 Total 0 1375237 i) 0 237307 977412

01\89 0 83383 (j (l 21033 84053 02\89 0 82105 0 (I 23103 116117 03\B9 0 77262 0 (I 16873 105b47 04\89 0 89972 0 0 12314 13000B 05\89 0 144474 0 0 12985 137801 06\89 0 142883 0 0 12228 147998 07\89 0 150802 0 (l 14677 170424 08\89 382921, 109035 0 0 23725 138937 09\89 392382 912B7 0 0 35401 109315 10\89 91409 86360 0 0 31696 11181?4 11\89 0 B3990 (l () 31326 134229 12\B9 0 63990 (I 0 31326 116300 Total 856717 1225550 0 r) 2666Bb 1S02725 - ... ~.....,_ 'i ...,/ Table 5.2.1. - Water License NIL3-0043 - Honthlv water Useage log Page 2 of 2

Pu1ped Treated A Shaft Fro, Kinewater Coapressor 6round Carbon 6reat Discharged Cooling llater Water Date Colu1n Slave To Bahr Water Froa City Seepage Ito/Yr Discharge Lake Creek Discharged Of YK Froa U/6 K3 K3 N3 H3 K3 K3 43· 1 43-4 43·7 43-8

01\9(1 (j 83990 (I 0 3132b 60386 02\90 1) B3990 i} 0 31320 32856 03\90 0 83990 0 0 12315 5010 04\90 0 132626 0 0 7052 421t93 05\90 270584 139865 0 0 1155 47087 Ob\90 5881.96 noab 0 0 180/iB lt17Bb 07\90 605534 125127 0 0 23895 2251+9 00\90 b16273 105846 (I 0 21,42 18912 09\90 620396 120477 0 0 25816 19752 10\90 (l tl1471 0 (j 207'76 7217 11\90 0 160865 lj 0 25456 3459 12\90 0 10470'1 i) 0 23226 23903 Total 2701483 1325042 (I Q 223055 345410

01\91 0 68213 0 0 2b8ll 75B9 02\91 0 83385 v 0 11695 4457b 03\91 0 53887 0 0 26332 17859 04\91 ·o 58453 0 0 26332 37282 - 05\91 131823 60567 0 0 13956 12212b 06\91 538685 57796 0 0 2544 36059 07\91 697140 37341, (l () 824 6883 08\91 682816 46352 0 0 1273 377(1 09\91 290276 42085 0 0 1415 12410 10\91 0 56182 0 0 1400 b232 II \91 0 68327 (/ i) 1013 3431 12\91 0 73299 (I 0 266 6713 Total 2340740 705892 {I ~ 113861 304930

OJ\92 0 102702 0 0 1135 80347 02\92 0 162932 0 0 902 39065 03\92 0 H,2832 0 0 1259 30198 04\92 0 164470 0 0 ll,15 4856 05\92 0 12877B 0 (I 17B2 10201 06\92 119030 124624 0 0 1725 9872 Total 119030 846238 (j (, 8418 174539 ROYAL OAK MINES INC.- LICENSE N 1 L3-OO43 Figure 5.2. 1. Pattern of Weter Useoge 340' 320 300 280

L 260 C I) 240 t 220 I.I .... -- 200 ~~ C '+-- C 180 0 fJ t? ~ 160 !l i= u- 140 ~ 120 u ·-.0 :J 100 () 80 60 40 20

0 I 1987 1989 1988 1990 1992

□ Giant Pumphouse + Groundwater from UG <> Totol Weter Used Mex Allowable Use In this time period the average consumption of water has been as follows:

Freshwater Pumped from Great Slave Lake through the mine pumphouee 1,204,784 M3/Year

Groundwater Pumped from the U/G Mine 710,718 M3/Year

Combined Total 1,915,502 M3/Year

The schematic water balance for the Giant Mine showing where the water is being used is presented in figure S.2.2. The pattern of water usage averaged over an annual basis is presented graphically in figure 5.2.3.

However on a month by month basis, the tota: consumption of water (freshwater plus groundwater) has exceeded the license limit for 28 out of 66 months ( 42. 4\ of the :.ime 1 • The majority of theee occurrences (20 out of the 28 1 occurre= ~~ tne second half of 1988

and all o: 1989. The follow1n•0: :.:ire.;; :factors in order of significance explain the anomolie~ consumption that were experienced during this period:

a ) In the summer of 1988, 1989 a:-: = 199 C the Tailings Retreatment Plant was operational and the consum?:.ior: :::: freshwater pumped from Great Slave Lake was increased.

b } In May and June of 1988 two sigr:ificar:: rainfall events added significantly to the volume c : groundwater that entered the underground mine workings. consequent:..y the volume of groundwater pumped out of the mine in the Spring of 1988 was greater than normal.

C ) I n November of 1987 the Nortnwes:. Tailings impoundment area was first used for the depos::.~1.or. o : rr.i:l tailings. In the following year there was a ve:.-:: ra~.:.d a:-:. ::: significant riee in th8 groundwater seepage ir.:.:; :.,.;;, :.inaer;rounci mine through the mine workings located in the area::: the Northwest Tailings impoundment. The chemistry c: this wate=, principally the presence of low concentrations c: total cyanide made it clear that the increase in groundwater was directly associated with leakage from the Northwest Tailings impoundment. The volume of groundwater pumped out of the underground mine was high during the swrrner of 1988, dropped c:: over the winter months and then rose again in the Spring ar:= summer cf 1989 . This water was collected underground, pumped t o surface and returned to the tailings area through the mi::, however in so doing this, this water was counted as groundwate:.- thus causing the total reported volume of water consume=::.~ 19So and 1989 to exceed the license maximum allowable limi:.. The Supercrest mine dewatering pumps now return tne maJority of this leakage directly to the Northwest Tailings impo:.inciment . The subsequent , . .,... __ deposition of tailings in the Northwes~ Tailings irnpoundment has reduced the rate of·~ leaKage of ta::.l ings solution into the underground mine. City of Nine Undel'!P'Ound Groundllder !felloibife fresmter Nine ---• Seepage llater Sqpply l'wlpblluse lleNtuing l Dcl•stic - Undel'!ll'OUlld llill lloistuN! Potable Water- · lline - Nine11ater in ore l'wlphouse Stonge hnk

lline r To111site ....Stea BoiltM ----. 1 -- L... llill Process l llill Process

Co~SSOI' ____ r ~· Nine .. Slll'lace Cooling ... llater ... Buildings .... llill hilings Pwlps

Tailings Se11age Ponds

l Decant to Iva,ontion Effluent Pore llatel' Treat•nt Seepage

S1114.ge Settling Pond figure 5.2.2. Royal Oak Mines Inc. Dischal'!l'e Yellowknife Division To The Giant Mine F.nvil'Dnlll!nt Scheaatic llatel' Balance

* Uollllll!s quoted are based on averages fol' the period 1987 thru 1991 - -- --lh corl'l!ctions have been 11ade for tlo1111ete11 emM ROYAL OAK MINES INC.- LICENSE N 1 L3-OO43 J Figure 5.2.3. Pattern of Weter Useoge 3 2.8 2.6 2.4 L C 2.2 >-IJ ~ 2 I.) +' 0,,-._ 1.8 ~ Pl C .... 0 0 != 1.6 ~ ~ 1.)- 1.4 +' l) ~ 1.2 u :0 1 u::J 0.8 0.6 0.4 0.2 1987 1988 1989 1990 1991

D Total Weter Used -- Mox Allowable Use <> Giant Pumphouse /:i. Groundwater from UG

:a; 7~~ ., .~• • II,•

The reasons for this increase in apparent water conawnption were discussed with the NWT Water Board and the Water Resources branch at the time cf their occurrence and an emergency amendment to the license was requested. The factors that resulted in the increased pattern of water usage in 1988 and 1989 are perceived to be aberrations and are not indicative of actual usage. Consequently, Royal Oak Mines Inc. respectfully requests that the maximum allowable consumption of water be maintained at 1,950,000 cubic meters per year in the license renewal.

In addition freshwater is taken from the City of Yellowknife and then chlorinated for use as potable water both at the mine townsite and throughout the minesite surface facilities. During the time period 1987 through 1991 the volume of water drawn from the City of Yell owknife averaged 172,000 M3/year. It should be noted that in 1990 and 1991 the quantity of water returned to the environment tnrough Bake= Creek exceeded the 1,950,000 cubic meter maximum allowe=. The quantity of water treated and released frorr. tne tail:i.ngiJ impoundment areas during the time period 1987 through 1991 ~s shown graphically in figure 5.2.4. In 1988 no water was treated or released due to the startup of the tailings retreatmer.~ plant and the pilot testing of the hydrogen peroxide e!flue'"~ treatment process. This period of no release has the ne~ result of skewing the volume of water released in subsequen~ years. On average the quantity of water treated and returned ~o Baker Creek during this time period averaged 1,444,621 cuc:c meters per year.

5.3 Length of License At the end of 1991 the known ore reserves a~ tne Giant Mine were as follows:

Tons Grade Ounces (OOO's) (oz/ton) (000'&)

M1neable Ore 2,339 0.311 727 Mineralized Material 3,407 0.227 773

Total 5,746 0.261 :.,soo

At the current mine capacity of 100 ,000 ounces of gold output per year, the mine has mineable ore reserves of 7.27 years with good potential for an additional 7. 73 years c: reserves as ongoing exploration converts mineralized materia: in~c mineable ore.

Based on these reserves and an anticipated mine life of at least 15 additional years, Royal Oak Mines lr.c. respectfully requests that the water use license for the Giant Mine be renewed for a further 10 year period, May 01,1993 through Apri: 30,2003.

The NWT Water Board has now had ten years o: experience with the performance of the Giant Mine in relat:i.on t o i ts water use license. While not perfec~, the mine has exercised due diligence in acting as a good corporate citizen to minimize the harmful effects of its operations on the natural environmer.~. The extension of this renewal ROYAL OAK MINES INC.- LICENSE N 1 L3-0043 ~ Figure 5.2.4. Volume of Tailings Decant 3

2.8 2.6 2.4

L. 2.2 C I) );_ 2 L. I) 1.8 +'c-. 3: C"' 1.6 ~ 0 0 ~ ~~ 1.4 1)- +' I) 1.2 ~ u 1 :0 :, (.) 0.8

0.6

0.4

0.2

0 1987 1988 1989 1990 1991

□ Decant to Beker Cr + Mox Allowable Use

~ period from five to ten years provides Royal Oak Mines Inc. with the security that provided it remains in compliance with the terms of its water use license it can continue operations at the Giant mine during this time period. This security of tenure is important to Royal Oak Mines Inc. and ultimately to the NWT in that it provides a more stable framework for planning future investment and use of capital at this operation.

The conditions contained within the License provide the NWT Water Board with adequate protection should changes in the license conditions be necessary due to changes in legislation or regulations. A longer term license wou l d provide Royal Oak Mines with some security that it can stay~~ operation provided in remain in compliance with the license terms .

5 .. f Performance Under the Current License Term Royal Oak Mines has reviewed its pe=forrnance d~ring the term of the existing license t o assist in assessir.; tne effectiveness of the mine•s pollution contro l systems:

5.4,l Water Quality The current license specifie :! -:na:: a : i ....-astes discharged must meet the following cri teria:

Parameter Max Average Ma>: Co:,centra-:ion Concentration cf a,.,,. Grab Sample

Total cyanide 0.8 mg/1 :. . 6 rng/l Total Arsenic a.a mg/1 :.6 mg/: Total Copper 0.5 mg/1 :.o mg/l Total Lead 0.2 mg/1 ::;. 4 mg/: Total Nickel 0.5 mg/1 :.o mg/l Total Zinc C.2 mg/1 :.4 mg/1 Suspended Solids 15.0 mg/1 2:. 0 mg/1 Total Residual ,., . Chlorine ~ • l mg / ! rng .- . o.:.. :i. and Grease :. • ,j mg / : pH Minimum 6.0 pH unitE Maxi.mu~ 9.0 p~ units

The analytical data collected by the rnine under the Surveillance Network Program for both the water discnarged into Baker Creek from the Tailings ponds (Station 43-lJ a~c f~" the quality of water at the mouth of Baker Creek (Station 43-5 1 for the time period 1987 through June of 1992 are presented:..~ Table 5 . 4 . 1.

Total Cyanide concentrations The total cyanide concentrations be-:~ :..n the discharge from the tailings pond into Baker Cree~: ( st.a-::..c:-; 43-: , and at the mouth of Baker creek ( station 43-5) are presented graphically in figures 5,4.1. and 5,4.2. respectively fc= tne time peri.cd 1987 through June 0~ 1992. - .. _.._ On two successive occasions i~ late 19~7 the concentrations of total cyanide exceeded the maximum allowabl e concentration of any grab sample of 1, 6 mg/1. These occasion5 resulte-:! from late season operation of the effluent treatment plant. As the air temperature fell in the fall of 1987 the effectiveness of the chlorine additions to oxidize the cyanide contained in the tailings pond decant decayed rapidly. Consequently the plant failed t o meet the required specification for total cyanide, copper and nickel, The company was charged under the Northern Inland Waters Act with these violations by the Department of Indian and Northern Affairs. A hard lesson was learned in the fall of 1987 abou~ the kinetics of cyanide destruction at low temperatures. In the following year the company took action by testing and then converting from a chlorine oxidation system to the use of hydrogen peroxide fer the destruction of cyanide.

While on one other occasion the concen~ration of cyanide in the tailings decant exceeded 0. 8 mg/:, the average of any four consecutive samples did not exceed tne maximum average concentration of 0.8 mg/l (with the exception c : the above noted incident). cyanide concentrations in both the tailings decant and Baker creek were observed to increase during the Sul!'.me r s :: : 1989 and 1990 due to the operation of the Tailings Retrea~rne::: Pla:-::.

Total Arsenic Concentrations The total arsenic concentration~ oc::: ::: the discharge from the tailings pond into Baker Creek (stet:c:. ~~-: and at the mouth of Baker Creek ( station 43-5 ) are presente.:l g::-aphically in figures S.4.3. and S.4.4. respectively for tne time period 1987 through June cf 1992.

The maximum concentration of any gra~ sample a: 1. 6 mg/1 was not exceeded at any time during the license period.

However in July and August of 199': tne compa:::· experienced severe difficulty in keeping the average arse::.:~ concentration within the license limits. Individual samples exceeded 0.5 mg/l on 10 occasions between January of 1987 and June c! 299~ ~it~ S of these occasions occurring i:-. 199C. The average ::.: ::c·.::· consecutive samples did excee= the maximum average conce::.tr~::~:: c: :.~ mg/1 over samples taKen between Juiy 09th and the 24::-. a::..:i over samples taken between August 21st and September 10th. Th~ problems encountered in 1990 were due to the operation of the t a i l ing~ retreatment plant. The discharge from this operation effectively dc~bled the volume that had to be treated through the efflue::.: treatme::.: plant significantly reducing treatment retention time. Tne concentrations of arsenic in the feed to the effluent treatme:-:~ pla:-:: also increased during periods when the tailings retreatme::.t pla.. ~ was operational further reducing the effectiveness of the treatme::t process. The capacity of the effluent treatment plant was increased in 1990 and a record 634 million imperial gallons were treate:.:. The addition of ferric sulphate was also increased by lE . f oased :::: weigh~ of ferric sulphate consumed per million gallon~ treated , however the system failed to meet the license criteria i ~= arsen~= in July and August c: 1990.

With the subsequent closure o: the tailings r etreatment plant in 199:, the mine•s effluent treatme::~ syste~ na~ been able to meet the license criteria for arsenic concentrations , a!~hough in some cases just narrowly.

Total copper concentrations The total copper concentrations both in the discharge from the tailings pond into Baker Creek (station 43-1) and at the mouth of Baker Creek ( station 43-5) are presented graphically in figures 5.4.5 and 5.4.6 respectively for the time period 1987 through June of 1992.

On two successive occasions in late 1987 the concentrations of total copper exceeded the maximum allowable concem:ration of any grab sample of 1.0 mg/1. These occasions resulted from late season operation of the effluent treatment plant. As the air temperature fell in the fall of 1987 the effectiveness of the chlorine additions to oxidize the cyanide contained in the tailings pond decant decayed rapidly. Consequently the plant failed t o meet the required specification for total cyanide, copper and nickel. The copper and nickel are both complexed with cyanide and thus when the cyanide is not effectively destroyed the copper and nickel also remains in solution. The company was charged under tne N~rthern Inland Waters A=t with these violations by the Departmen~ c: Indian and Northern Affairs. A hard lesson was learned~~ the fal l of 1987 about the kinetics of cyanide destructio:-, ... _ lo:,· temperatures. In the following year the company too~; a::~ior: i: ::,· testing and then converting from a chlorine oxidation system ~c the use of hydrogen peroxide for the destruction of cyanide. With the exception of these two occasions in 198; , all other samples collected and analyzed between January o: 1987 and June of 1992 were below the maximum allowable total copper concentration of 1.0 mg/1.

Individual samples exceeded the O.~ mg/ : maximum average concentration for total copper o~ ~~ cccasi.or.s between January of 1987 and June c: 1992, 13 of which c::c~rred ~~ 1990.

The company experienced extreme :::!.:.:fi.cul-:·: ,;hroughout 1990 in achieving the license criteria c: C.S m;: :::= the maximum average concentration cf total copper containe= :~ ~ne discharge from the tailings pond. Approximately SO\ c: tne 26 s~~ples of tailings pond decant analyzed i.n 1990 exceeded the 0. S mg/ l license criteria. Operation of the Tailings Retreatme"~ Plan~ during both 1989 and 1990 added significantly larger guan~ities of metallo-cyanide complexes into the Northwest Tailings pond. These cyanide complexes had little natural ageing time resulting in significantly higher concentrations of copper and nickel cyani.de in the feed to the effluent treatment plant. The opera~ion cf tne Tailing Retreatment Plant also resulted in higher volumes c: water to be treated, effectively reducing treatment retention time. The two factors combined resulted in poor treatment performance for cyanide, copper and nickel in 1990.

Operation of the Tailings Retreatme.. ~ Pla~t was suspended at the end of 1990. The concentrations of copper contained in the tailings pond decant returned to more normal leve~s ~~ 1~9: and 1992 well within the license criteria. Total Lead Concentrations The total lead concentrations both in the discharge from the tailings pond into Baker Creek (station 43-1) and at the mouth of Baker creek (station 43-5) are presented graphically in figure 5.4.7 and 5.4.B respectively.

All samples collected and analyzed for total lead concentrations over the life of the current wate.::- use 11.cense were below the established license limit both for the maximum concentration in any Total Lead Concentrations:

The total lead concentrations be:.:-. i:-: the discharge from the tailings pond into Baker Creek (station 43-: ) and at the mouth of Baker creek (station 43-5) are presented graphically in figure 5.4.7 and 5.4.8 respectively.

All samples collected and analyze= fc~ tota: lead concentrations over the life of the current: wate.::- use l ;.cense were below the established license limit both fo.::- :.n e maxim~~ concentration in any grab sample of 0.4 mg/1 and the maxim~~ averaoe concentration of 0. 2 mg/1.

Total Nickel concentrations The total nickel concentrations cc-::. ;.:: tne: discharge from the tailings pond into Baker Creek (sta-:io~ 43-: 1 and at the mouth of Baker creek (station 43-5) are presented graph;.cally in figure 5.4.9 and 5.4.10 respectively between January c: 1957 and June of 1992.

As was the case for both copper and cyanide, the concentration of total nickel exceeded the maximum allowable concentration of any grab sample of 1.0 mg/1 on one occassion it. the fall of 1987. The maximum average allowable concentra~ ion of C. 5 mg / l total nickel was also exceeded on four occassions d~.::-;.r.? this same period in 1987, As described earlier this failure of the ~reatmer.-: system resulted from peer cyanide destruction experienced ouring la-:e season operation of the effluer.t treatmer.t system.

As was the case for both copper anc ::yania: . t. :ie company experienced extreme difficulty throughout 1990 : r. achiev.ng the license criteria of 0 . 5 mg/1 for the maximum avera~e concentration of total nickel contained in tne discharge from the t.ai lings pond . Of the 26 samples of tailings pond decant analyzed i ~ 199C, 10 samples exceeded the 0.5 mg/1 license criteria. Operation c: the Tailings Retreatment Plant during both 1989 and 199: addec significantly larger quantities of metallo-cyanide complexes into tne Northwest Tailings pond. These cyanide complexes ha:: little natural ageing time resulting in significantly highe!'" concentrations of copper and nickel cyanide in the feed to the effluen-: treatment plant. The operation cf the Tailing Retreatmen-: Pl an:. also resulted in higher volumes of water to be treated , efrectivel::· reducing treatment retention time. The two factors combined resulted in poor treatment performance for cyanide, copper and nickel;.:-: 1990. - ~...... Operation of the Tailings Retreatmen~ Pl ant was suspended at the end of 1990. The concentrations of nicke: contained ~n the tailings pond decant returned to more normal levels in 1991 and 1992 well withir. ~~·--..-,~ -:,:-, ,_~

the license criteria.

Total Suspended Solids Concentrations The total suspended solids concentrations both in the discharge from the tailings pond into Baker Creek (station 43-1) and at the mouth of Baker Creek (station 43-5) are presented graphically in figure 5.4.11 and 5.4.12 respectively for the cime period between January of 1987 and June of 1992. The suspended solids content of the tailings decant was consistently below the license criteria of 15.0 mg/ 1. The concentration of suspended solids measured at the mouth of Balter Creek showed a blip upwards each Spring which is due to natural sediment loading in the creek during the spring runoff.

pB MeasureaeDtS The pH measured both in the discharge from the tailings pond into Baker Creek (station 43-1 ) and at t ne mouth c ! Baker Creek (station 43-5) are presented graphically ir. figure s.~.:3 for the time period between January of 1987 and June c f 1992. In a:l cases the measured pH was within the license cri~eria ~=pH 6. 0 t o 9.0. Royal Oak Mi nes Inc . respec~ive:. :.· requests en.at the N.w.-: . Water Board renew the Giant Mine water use :~cense w~~h no changes made to the current effluent criteria. In re·,•iew!.ng the pe rformance over the past five years under this efflue:-:: ::= i teria chere are two distinct periods during which the mine failed t.c consist:er.tly comply with the license criteria (late 1987 and in 1990) . In both of these cases the failure cf the treatment system is due to a n abberation that has since been corrected. The performance of the effluent treatment sys~em in 1991 and in 1992 reinforce the fact ~hat these abberations have been corrected. Royal Oak Mines lr.c . believes that with ongoing diligence the current license criteri.a car. be achieved with the existing modified effluent treacme~: plant.

6.0. Unauthorized Spills and Discharges Between January of 1987 and June c: !99~ . a total of 36 unauthorized spills were reported by Giant Mine := tne N. K. : . Water Board. These nave resulted in charges being l a;.:: -.:r.oe ::- che f,::::-cnern Inland Waters A::: o r: two separate occasion.; . Tr.;: company acknowledged its responsibility in both cases and d~ :: net concest the charges.

A listing cf these incidents in chro~ological order is presented in Table 6.l. In the majority cf these occurrences the size of the spill was small and all of the mat:erial released was contained and subsequently cleaned up.

Royal Oak Mines Inc. recognizes cna: r:o unauthorized spill or discharge is acceptable however in a~ operation as complex as the Giant mine incidents resulting from e ither system or human failure do occur . The company believes u:a : these should be deal-. with openl y and honestly sc that the r o::: causes i n each case can be identified and remedial action take~ t. c preve~~ recccurrence. - ...... ! n each case the mine sta~: i nves:~ga~e the cause of the incident and initiate action t o eithe::- mod:.::,· the s yscem or procedure to reduce the risk of a repeat inci dent . The types of remedial action that have been taken as a result of the■e incidents include:

- Construction of a containment system at the west and north end of the mill site. This lined containment pond complete with return pumps was constructed to intercept material inadvertently relea ■ed from the mill thereby providing containment and reducing the risk of material reaching Baker Creek.

- Modification of the Cottrell dust treatment circuit to eliminate a pipeline that had resulted in the release of contaminated slurry into Baker Creek.

Royal Oak Mines Inc. will continue to exercise due diligence to reduce the number of unauthorized discharges that have taken place over the past five year period. This reduction will be accomplished by:

1. Continuing to find means to improve the mechanical reliability of systems. 2. Installing or modifying systems to minimize the risk of environmental damage resulting system failures.

3. Training employees to be environmentally conscious of the consequences of their activities while on the job. The nature of these unauthorized discharges have been reviewed to determine if any pattern can be identified:

- Heavy rainfalls in the spring of 1988 resulted in six incidents where minewater was inadvertently released.

- A total of 16 of the 36 unauthorized discharges involved the release of tailings from the tailings disposal pipelines. The majority of these spills occur in winter and are due to a mechanical failure of the piping system. In 1991 and 1992 ten of the seventeen incidents reported resulted from mechanical failures of the tail1.ngs disposal pipelines. Royal Oak is planning to replace 6000 feet of the main tailings discharge pipeline 1.~ 1993 at a cost of approximately 560,000. The pipeline routing will be altered to ensure that wherever possible the natural drainage from the pipeline would be inside one of the existing tailings containment areas. This should reduce both the number of incidents and the severity of the consequences resulting from the mechanical failure of this system.

1.0. License Conditions

Royal Oak Mines Inc. has no immediate plans to modify or change the operating rates or flowsheet at the Giant Mine . consequently we request that the N.W.T. Water Board extend the current water use license through a renewal for a 10 year period. Royal Oak recommends that the current licenae conditions remain in place. The current conditions provide adequate protection for the environment as demonstrated by the past five years. These conditions have proven difficult to achieve but Royal Oak is confident that with due diligence it can operate within these conditions and meet the license requirements. u 0

I Tablt 6.1. Li1tint of Un1uthoriud Soills ud Di1enarau . ' 0 ' l'87 6 r427 s.,.. ,, of 2 113 of ai II 1tlution throu~h •est 1i II ull "u 18 Spill of 200 kq of 1r11nic lriosidt • .:;.,.~,' ,. ~r 08 Soill of 45 113 of till solution fro• ~ui~nnl brutdo•n ••, 21 Spill of 74 113 of hilin91 1olutiDn Ind ~TOCIU ••ter llov 23 5Dill of 15 N3 of llilin11 nluliOD • Dec 22 S~ill of 32 113 of taili1191 froe ruptund lint 50111 of 15 "3 of hilin~s 1olutlon • 1988 9 "·~ 09 S!,ill of 0.45 K3 of taili!MJ• throuqh ..,t 1ill ..u "av 22 S~ill of 90 K3 of 1i11t•1ter Kar 24 Saill of IS 113 of 1i111•at,r • Jun 05 Spill of 10 113 of 1i,...1hr Jun ~7 S~ill of 91 kq of 1111nit trioxide Jul 26 Spill of 109 113 of •intHltr • Jul 28 Spill of 1.6 113 of 1i11tHhr llov 24 Spill of 45 113 hiliftl!• uler D,c 02 Sail! of 109 K3 hilinqs frot ruptured oinch vilv• • l'18~ i J.n II A frntn 2' v1ht lh1•1d b! n Da. This nltr WH allowed to fre.u and thtn dU1ped • inside the 1oulh aond. hr 21 A ~u•p in lht 11n91 lift .talion vuit ind ••ttr overflo•tdl ■osU! 1inu1hrl into th, crusher aru. • Aporni11ltl~ JOO 9allon1 tide ii to th ro1d before iren1n9 ind this us nto•trtd and phttd in th, •odh pond. • 1990 2 llu 13 Condtnnlt .ahr •~ill .it rtfintr• - lohl of 0.9 N3 Tohllv cluned up Ind dtpHiltd inlo north•ut pond 0 Dec 0~ Diesel fuel Spill al the A-2 r11~ - Toh! of 1.8 II~ Discoloured sno, clHned uo and d1pos1 led into north1est pond 0 1991 12 Jan 14 Pinhole in hilin9s lint nnr bl38 ~it ~r 30 Pooled oil at I boiler (1ource unho1nl "·~ 07 Carbon phnt slurr! spi II () Ni• 09 17 ulchbuin onrflo• of runoff •aler llu 13 S.ddlt used to r1111ir Jan 1'\h hilinq, line pinhole luh~ llav 15 Carblft phnl frtsh 1iltr ~i II ~:·, Jul 27 8rt1k in i,inl in hiti1191 Jina to south po1141/tro Au~ 17 Split in hili1191 liM 1pprt1i ■1ltly i!/3 of lht 1ay up the road to the north.. ,t pond Auq 21 Bruk ti ioinl in hilinqs Jin, Cu■e ioint H My 27) 1) .., 28 Split in hilin!• lint 11t1r b3 pit llu 26 Pinholt ifl tai lin9s lint adiactnt lo 14 dH Dtc 18 Splil in hililllJS lint 11li1etnt lo 14 dH . ) 1992 s Jin 29 Da~ hnk 11 A Shift ovtrfilltd - lthl of 0,5 lo 1.0 113 of bunker c oil Spill conhintd-conh■inahd 1now and Hltrill dtoosil•d in lht NHh du■p 1t tht north•n ) 11.iy 26 lt1kin9 ulvt on oil 1hr1q1 hnt 1t A Shift t1nk hr•· tobl of 0.1 113 of Bunktr C Oil Spill conhintd Ind clt1ntd up - nlvt replaced ll1y 27 AtlHst of Frnhnt,r durinq power oul191 • SOO 91llon1 0 Udtr conhined in •ill c1lch11nl and nl~rntd to phnt. J~n 28 5!>lit in ICIPE piptlin. ftodin9 £fflu1nt ·lr11tnnt Pl1nt • 0.1 h 0.5 "3 of bilinq1 uluti Mdtr Hl!ltd into 9round • pipt 111 r1~1ired Jun 30 Holn dtilltd in HDPf pi~tlint fttdi119 Efflutnl Trntaenl Plant ) •...,·; - (" 1 l ABLE 5.4.t. RDYM. OAK "lltES - YELLOIIDIFE DIVISION IIAlER, USE UCEIISE - HISTORICAi. DATA (') Shtion :r,3-5 BAKER CREEK

, Tohl S,ec, iu5!1, Tobi hhl lohl lohl lohl lot1l 0 hgt I pH RH, Cl tond. Solids As CN Cu Ni Zn Pb Nll31N Tft!I, IIIJ 19/1 ■S 1911 19/1 119/1 ICJ/I 19/I 19/1 1911 ■g l l dt9, C PP' ~ 04\05\87 7.3 0.03 0.33 30., 0.06 0.75 o.os 9.04 0.04 0.02 0.92 4 • 11\05\87 7.3 0.04 0.2 IU 0,08 o.os 0.09 0.03 0,04 < 0.10 0,14 6 19\05187 7.05 0.02 0.13 10.4 0.04 0.02 0.03 0. 11 0.03 < 0.10 < 0.10 4 25\05\B7 7.1 0.06 0.11 11.2 0.06 G.48 0.07 o.oa 0.03 < 0.10 0.12 10 • 02106187 7,1 o.o• 0.11, 12 0.18 0.03 0.21 0.03 o.~ < 0.10 0. 17 13 09\0l,187 6.95 0.04 O.H 7.2 0.11 0.18 O.H < 0.10 o.o, < 0.10 < 0.10 15 15106IB7 7.2 0.02 0.17 23.2 o.u 0.11 0.15 < 0.10 0.06 < 0.10 0.1 13 < 0. 10 • 22\0"87 7.45 0.02 0.24 3.7 0.22 < 0.01 0.13 < O.tO O.OS < O.tO 0.11 18 29\06187 7.45 0.06 I.BS u 0.49 0.19 0.15 0.18 0.08 < 0.10 3.5 H 0 09\07\87 7,1 0.06 2,2 3.2 G.31 0.2 0.31 0.12 0.07 < 0.02 4.7 15 < 0.10 13\07187 ,.e 0,04 2.7 t.9 0.56 0.14 0.26 0.02 O.OB < 0.02 6.2 18 r ; 20\07\87 7.6 0.06 2.7 3.7 0.54 0.11 0.05 0.2 u, < 0.02 8.2 18 0 27107\87 7.3 0.07 3 3.2 Ml 0.11 0.02 0,IS 0,06 < 0.02 8.6 18 0"08187 7,6 0.07 3.2 1.9 0.3' 0,1 0.1 0.19 o.o, 0.04 8.1 15 < 0,10 ; I 12\08187 7.45 0.06 2.95 t.2 0.38 0.12 0.12 0.12 0.07 0.04 10 14 0 17\08187 7.45 0.01 2.75 2.2 0.24 0-21 0.06 0.21 0.06 0.04 9.B 18 26\08\87 . 7.4 0.06 3.1 1.9 0.31 0.34 0.04 0.3 0,04 o.os 9,B 13 0 31\08187 7.5 0.08 2.41 S.7 0.23 0.17 0.16 0.34 0.06 0.04 9.9 9 0 08\09187 7.35 0.12 2.55 3.3 0.2 0.09 0.02 0.33 0,0(, < 0.01 9.7 10 < 0.10 14109187 7.3 0.7 2,5 u 0.36 0,27 0,07 0.38 0,06 0,02 9.4 10 0 21\09\87 ,., 2.1 2.7 4.3 0.2S UI 0.06 G.59 0.05 0.04 8,1 8 0 28\09187 7.1 2 u 2.6 M 0.1, 0,2 0.3S 0,04 o.~ 8.8 7 05\10'87 7.2 2 2.5 3.2 0.16 0,22 0,09 0.4 0.04 0,06 u s 13\10187 7.15 J.4 2.25 4.9 G.l4 0.2, 0,11 0.36 0.06 0.04 8.B o < o.io 0 19\10\87 6.75 2 2.3 5.5 0.23 0.2, 0.12 0.5 0.04 0.05 7.4 0 26\10\87 6,75 2 2.15 2., 0.11 G.35 0.2 G.62 0.11 o.o, u I 03\11187 7,2 0.18 2.4 2.6 0. 18 1.12 0,92 0.82 0.07 0.03 6.2 0 0 09111187 6.95 0.3 2,05 2.8 0.27 2.38 1.5 0.86 o.o, 0.04 5.98 0 20\11\8, 7.15 O,l 2.95 3.4 0.3 3.6 1.92 I.II 0,06 0.02 u 0 Aver,~• 7.22 M B 1.92 6.18 0.26 0.42 0.25 o.n 0.06 0.02 S.7' 10 0.000 0

0

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0 ,

y V ..1 s.u. ROYAL DAI: NINES • YELLOllklllFE DIVISION 0 UATER 115( LICENSE • IIISTORICAI. DAlA

I St,tion 43·5 8Ak£R tREEK 0

1 T1l1I s.,c. Susa. lotil Tohl Tohl Tohl Tot.I Toh! ,__ ,.,, 2 pl! I Rts. Cl CDnd. Solids Al DI Co Ni Zn I'll Nll3/II "9 0 19/1 ■S 19/1 19/I 19/I 19/I 19/I 19/I 19/1 19/I d19'. C ppb

'' · 02105\88 7.5 < 0.10 0.82 30.Z 0.46 0.18 0.21 0.1 0.06 0.02 1,85 0.5 09\05\88 7,7 0.04 0.37 70-2 0.21 0.05 0.06 0.11 0.04 { 0.02 0.64 0 • 16\05\88 7.8 0.05 0.98 3.\2 0.14 0.01 o.G9 o.os 0.06 { 0.02 0.98 4 0.090 24105\88 7.7 0.05 0.21 59,9 0.09 0.02 0.09 0.1 0.04 0.03 0.27 7 0.050 30105\88 7,6 0.04 0.16 31,S 0.04 0.03 0.08 0.02 0.02 < 0.02 < 0.10 9 0.070 • 08106188 7.5 0.04 0.13 30.8 0.11 0.07 < 0.02 < 0.02 0.04 < 0.02 < 0.10 15 0.120 14106\88 6.7 0.04 0.11 9.8 0.06 0.02 0.02 0.02 0.03 0.05 < 0.10 n < 0.02 20\06188 6.2 0.04 0.12 12.2 0.05 0.06 0.02 0.04 0.02 < 0.02 < 0.10 13 0.050 • 27106\88 6.S o.o~ 0.13 6.3 0,13 0.02 0.03 0.01 O.Oo 0.01 < 0.10 18 04\07188 6.5 0.04 0.1' 59.2 0.03 o.es 0.04 0.02 0.03 < O.Oc < 0.10 13 0.060 11107\88 , 0.04 0.12 11.5 0.02 0.06 0.01 0.02 0.02 0,01 < O.JO 18 0.100 • 18107\88 6.9 0.04 0.12 75.1 o.os 0.06 o.os 0.11 0.08 G.03 < 0.10 18 0.100 25107\88 6.4 0.04 0.16 45.6 0,07 0.02 0.02 0.01 0,03 0.03 < 0.10 17 0.100 02108\88 7 0.04 0.11 28. 7 0.04 0.03 0.01 0.04 o.os 0.04 < 0. 10 9.100 • 08108\88 7.3 0.05 0.11 1,.3 o.os 0.02 0.02 0.01 0.03 0.01 < 0.10 "IS 0.100 n\08189 1.1 0.04 0.11 u 0.01 0.03 0.01 0.01 0,02 0.01 < 0.10 17 0.090 22108118 ,., 0.04 0.12 7 o.os 0.02 0.03 0.01 0.03 0.01 < 0.10 17 0.080 • 29118\88 6.8 0.04 0.12 6.2 0.06 0.01 0.03 o.ot 0.03 0.01 < 0.10 16 0.160 06\09\98 6.7 0.04 0.13 6.7 0.06 0.02 0.02 0.01 0.03 0.01 < 0.10 12 0.150 mo9\88 6.9 o.os 0.13 3,S 0.06 0.02 0.02 0.01 0.03 0.01 < 0.10 12 0.090 • 19109188 1 0.03 0.1 2.4 0.03 0.03 0.02 0.04 0.01 ( 0.10 7 0.080 26109\88 7 0.04 0.12 10.8 0.04 0.01, 0.01 0.03 0.01 < o. 10 4 0.110 03\10188 7 0.04 0.14 4.1 0.07 o.o, o.o, 0.02 o.o, 0.02 < 0.10 3 0.!40 • 11\10188 6.9 o.o, 0.14 S.5 0.07 0.02 0.05 0.01 0.03 0.03 < 0.10 4 0.100 17110\98 7 0.03 0.1s 9 0.09 0.04 0.04 0.03 0.04 0.02 0.1 2 0.080 24\10\88 6.7 0.04 0.15 u 0.06 0.06 0.06 0.03 0.04 0.02 0.1 I 0.080 • 31110188 6.8 0.04 0.18 7.2 0.07 O.O'I 0.08 0.02 o.o, 0.03 0.1 I 07111188 6.7 0.04 0.21 6.S 0.06 0.1 0.04 0.01 0,03 0.01 0.1 I 0 14111\88 6.7 0.04 0.31 6 0.09 0.08 0.09 0.08 0.06 0.04 0.2 I 0.078 21\11188 u 0.04 0.34 5.5 0.07 o.o, 0.03 0.05 0.06 0.03 G.2 0 o.m 28\11\88 6.5 0.04 0.12 5 0.04 0.08 0.07 0.04 0.02 0.01 0.3 0 0.015 0 05\12\8B 6.4 0.03 0.13 ,.6 o.o, 0.04 0.01 0.01 0.03 0.01 0.3 0 0.030 12112\88 6.S 0.04 0.15 4.4 MS 0.05 0.03 0.02 0.02 0.01 0.3 0 0.028 19\12\88 6.4 0.04 0.18 4 o.os 0.05 0.04 D,02 D.03 O,Ol 0,3 0 o.m ,) ..., .,. 6.9 o.o~ 0.18 27.65 0.08 o.os o.os 0.03 0.04 0.02 0.17 8 r }

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.J ... VI V \.....) .• l ... .1E5.~.I. ROYAi. OAK "INES - YEllOWNlfE DIVISION .[ 0 WATER USE LJCENSE - HISTORICAL DATA

I Station 43-5 9AKER CREEK 0 , Told S~tc. Su,~. lohl Toh! Toh! Toi&\ Told Tol&I P:a9e 3 oH t Rts, Cl Cond, Sa lids A1 CM Cu Ni 2n Pb 11113111 T11p . lie! 19/1 .s 19/1 119/1 •9/1 19/I 19/I 1911 19/1 •tfl de9, C pp\ • ® 01\05189 6.6 0.05 0.16 66.90 0.13 0.06 o.o, 0.02 0.04 0.02 us I 0,100 08105189 6,5 0,04 0,18 211.00 0,07 0.02 0.04 0.03 0,07 0.01 o.2S 2 0.100 • 15\05189 6.1 o.c.• 0.12 86.00 0.05 0.02 0.05 0.05 0.04 0.02 0.31 4 0.070 23\05\89 •. s 0,03 0.14 9.00 0.03 0.04 0.02 0.01 0.02 0,02 o.~ 7 O,OoO mos,89 6.5 U2 0.18 ,.oo 0.02 0.01 0.02 0.02 0.02 0.04 0.15 13 0.(160 • 05106\89 6.5 0.02 0,19 3.90 0.03 0.02 0.02 0.02 0.02 0.04 0,12 15 0.050 H\06\89 6.7 U 3 0.17 4.00 0.07 0.03 0.02 0.02 0,02 0,06 0.10 18 0.150 19106\89 7.0 0.01 0.19 2.00 0.09 O.Oo M4 0.05 4.02 0.01 o. 10 17 0.080 • 26\1111\89 7.J 0.02 1.20 5.40 0.13 0.10 0.09 0.05 0.04 0.06 0.19 16 o.oso 04\07189 ,., 0.03 0.80 6.00 0.19 0.13 0.14 0.12 0.06 0.04 0.16 14 0.050 10\07189 7.5 0.02 I .JO 5.10 0.12 0.11 0.07 o.08 0,03 0.09 0.20 17 0.040 • 17\07\99 7.8 0.04 1.75 5.00 0.59 0.20 0.12 0.13 G.$9 0.05 0.25 24 0,060 e4\07189 7.4 0.02 1,30 9.10 MB 0.16 0.15 0,09 0.07 0.06 0,20 1B 0.020 01\01\89 7.6 0.01 1.30 7.00 0.48 o.u 0.14 0.30 O.C2 G.06 0.16 18 0,050 • 08\08189 7,5 0.01 1.10 3.00 0.75 0.30 0.2i 0.14 0.02 0.04 0.12 22 0.040 14\08\89 7.7 0.04 2.18 3.80 0.78 0.33 0.45 0.15 0.06 o.o, 0.20 22 0.070 21\08\89 7.9 0.08 1.83 4.36 0.80 0.38 0.48 0-22 0,07 0.07 0.36 14 0.040 • 28108\8' 7.8 0.04 1.84 3.80 0.76 0.30 0.38 0.14 O.C6 o.u 0.39 12 0.090 05\09189 7.8 0.04 2.20 3.80 0.74 G.48 M2 0.2, 0.06 0.06 0.35 16 0.040 0 11109\89 7.9 0.06 1.90 3.10 0-68 o.50 0-48 0.35 0.06 0,07 0.37 10 0.050 18\09\89 7.9 0.05 1.90 3.70 0.7' 0.45 0.50 0-44 0.05 0.05 0.32 7 0.045 l 25109\89 7,9 0.08 1,83 4.34 0.74 0.40 0-48 0.22 0.07 0.07 0.36 14 0.045 0 02\10\89 7.9 0.07 2.10 3.38 o. 72 0.50 0.55 G.40 0.03 0.04 t.30 5 0.053 10\10189 7.9 O.O'l 2.00 3.00 0.54 U3 o.48 o.39 0.03 0.03 0.30 4 0.038 16110189 7,7 0.06 1.90 1.96 0.56 0.35 0.45 0.38 0.03 0.04 o." I 0.045 0 23110\89 7,2 0.03 I.SO 1.60 0.52 0.27 0.52 o.40 0.02 0.08 0.20 I 0.053 30110\89 7.1 0.02 1.50 1.50 0.39 0.25 0.28 0.30 0.02 0.02 0.18 0.5 0&111\89 7.0 0.02 1.50 I.BO 0.28 0.19 0.24 0.28 0.02 0.03 0.18 0.5 0 Avtn~e 7.3 0,04 1.22 16.72 0.41 0.22 0.25 0.18 0.04 0,05 0.2, II 0.060 <\. 0

0

('I

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r ) .' ) I lEM. I. ROYAL OAk NIIIES - YillOWlllfE DIVISIOII 0 WATER USE LICENSE - IIISTtJIICAl DATA - ' ) Shtion b-5 IAKUCRUK 0 , Totd Spec. Susa. Tohl Tol1l Tohl Toti I Tol&l Total Paqt 4 pH I Rei. Cl Cond. S.lids As CII Cu Ni Zn Pb Nll3/N h•P• ff! 0 19/I ,s 19/I •~II 19/l 19/1 19/I 19/I 19/l 19/1 deg, t opb

23\04\90 6.7 o.ss U.'15 0.65 G.20 0,17 U4 o.os 0.01 0.34 I • 30\0"'10 6.8 0.58 10.65 0.1B 0.03 0.11 0.03 0.05 0.01 0.42 I ,.1 • 07\05\'IO 0.22 66.90 0.12 0.03 0.07 0.03 0.05 0.02 0.31 4 IS\05\90 7,1 0.28 109.90 0,09 0.03 0.04 0.06 0.06 0.02 0.34 4 22105\90 ,.s 0.26 15.96 0.09 0.02 o.os 0.03 0.04 0.01 0.34 8 • 28\05\90 6.8 0.30 IUO 0.10 0.08 0.08 o.oe o.os 0.03 G.48 12 04\06"0 Ml! 12.40 0,15 0.11 0.09 0.08 0.04 0.04 6.50 12 12\06\90 7.2"' 0.38 10.00 0.11 o.u 0,09 0.07 0.03 0.04 0.56 12 • l9\06\90 7.7 0.54 9.93 G.29 0.19 0,25 0.18 0.03 0.11 0.52 H 25\06\90 7.7 1.00 8.83 0.33 0.21 o.31 0.16 0.06 0.02 0.58 18 03\omo 8 1.20 7.80 0.39 0.20 0.25 0.18 0.04 o.os 0.8' 18 • 09\07\90 7.7 1.35 7.06 o.41 o. 15 0.18 0,14 0,06 0.06 o.90 20 0 16107\90 7.6 1.70 9.90 0.58 0.30 0.37 O.:ll 0.06 0.14 O.SB 2]\07\90 7.9 1,60 6.47 0.57 o.24 0.17 0.20 0.04 0.03 o.90 17" • 31107\90 7.7 1,70 5.90 0.64 o.26 0.21 0,05 0,88 . ·, o.es 0.03 19 07\08\90 u 1.60 5.57 G.62 0.25 0.18 0.2' o.o, 0.02 0-90 18 13\08\90 7.7 1.70 4.80 0.78 0.33 0.26 0.44 0.06 0.07 0,90 18 • 20\08190 7.B 1.70 6,40 0.78 0.33 0.24 0.30 0.06 0.08 o.91 16 0 2?\08\90 ?.8 I.BO 5.80 0.79 0.38 0.30 0.32 O.ot. 0.08 0.90 H 06109190 7.8 1.70 4.B0 Ul o.u 0.48 0.42 0.06 0.08 0.88 13 • 10109\90 8.1 1.90 6.00 0.72 0.33 0,46 0.54 o.os 0.08 o.90 8 () mo"n 7,7 1.80 6. 70 0.56 0.45 0.34 o.u 0.08 0.14 0.89 10 ,!4109190 7.6 1.90 6.80 0.68 0.30 0,30 0,'- 0.04 o.ot. G.89 10 • 01/10190 7.8 1.90 7.10 0.70 o.n 0.54 0.51 0.08 0.08 0.87 5 09\10\90 7.S 1.90 8.05 0.84 MS 0.0 0.5' 0.04 0.06 0.86 3 15\10190 7.5 1.20 8.00 0.74 0.61 D.42 0.60 0.04 0.08 0.92 2 • m10\9o 7.3 0.80 6.50 0.33 0.23 0.28 0.24 0.02 0.02 0.65 4 29\10190 7.5 M9 5.30 G.21 0.19 0.06 0.04 0.02 0.02 M2 I 0 05\11190 ?.4 0.15 4.66 0.16 0.09 0.06 0.06 0.02 0.02 0.19 0 03\12\90 6.5 0.19 uo 0,07 0.03 0.04 0.02 G.05 0.04 0.12 0 ' .. Avtri,, 7.S 1.09 13.36 0.44 U3 0.23 0.24 0.05 o.os 0.67 10 0 n

0

0

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0

0

I ' .. ta 1) .15.4.I. ROYAL OAX NINES - ffilOIIO'IF£ JIIVISJOI () MATER USE lJCEIISE • HISTORICAi. DllTA - I Shh•• 43·5 IAKEA CREEK (}

··\ , Tobi Spec. Susp. Total hhl Tthl hhl lohl Total P19t 5 pH f Rn. Cl Cond. Stlids As CN Cu Ni Zn Pb 113/N ltl!J, Ho! 0 11911 .s 19/I 119/I •9/1 .,,1 .,,1 •9/1 19/1 ~II d19, C ppb

4j 06105\91 7.S n 0,2 < 0.02 O.M 0.01 o.o, 0.01 I 13105\91 8 0.13 270.7 0.09 0,05 0,06 0.12 0.04 0.02 0.19 8 • 21105191 7,8 0.14 111, u, 0.02 0.02 0.06 0.02 0.12 0.21 13 27\05\91 7.1 0.23 11.2 0.01 0.03 O,M 0.06 0.02 0.06 0.19 13 0 03\06\91 7.5 0.2 u 0.12 0.02 0.02 o.o, 0.02 0.06 0.2 14 11106191 7.3 0.22 13 0.09 o.os 0.08 0.1& 0.02 0.08 0.22 15 17106\91 7 0.43 B.S 0.17 0.05 0.1 0.12 0,06 0.08 0,24 16 18106191 7.6 2.33 0.11 0.01 0.14 0,18 0.01 < 0,01 • 24106\91 7.6 0.32 9.1 0.37 0.1 0.16 u, o.o, o.oi. 0.24 18 02107191 7,9 0.52 8.4 0.1& 0.13 0.1 0,12 0.06 O,Oi 1.,s 21 0 08107\91 7.9 o.95 8.5 0.1 o.o, o.o, 0,J O.M 0.04 1,35 16 15107\91 ,., 0.9 6.5 0.56 0.11 0.08 u o.o, 0.04 1,2 20 22\07\91 8 1.4 S.B 0.57 0.15 0.26 o.ee o.o, 0,06 I 21 0 29107191 8 I.S 5 0.5' 0-24 0.2, 0.11 0.06 0.06 1.1 21 06\08\91 8.1 1.6 S.2 0.5' 0,19 0.06 0.2 0.02 0.06 1.05 20 12108\91 8 1.7 u G.3 0.13 0.1 0.18 0.02 0.02 0.9 20 0 19\08\91 8.1 1.5 3.8 0.35 0.09 0.08 0.14 0.02 0.1 I.I 18 19108\91 0.65 ~) 21108\91 0.67 0 24108191 0.79 28\08\91 8.3 1., 3 0.82 0.08 0,08 0.3 < O.Ol? () < 0.05 1.8 14 "'-.,. 29108\91 0.16 0 03\09191 a.a 1.5 1.8 0.74 o.oa 0.16 0.15 0.02 < o.os 1.9 Ii! 09109\91 8.1 u 2.2 0.72 0.08 0.16 0.19 0.06 < o.os 1.8 10 24110\91 7 0.43 9.5 1.2 o.os o.os 0.01 0.04 < 0.01 0.96 I 0 2'110\91 0.74 0.09 0.08 < 0.05 29\10\91 7.1 0,28 6.1 0.13 o.os o.oc < 0.01 0.02 0.02 o. 74 29110\'1 0.16 { o.os o.o, 0.07 0 Oi\ 11\91 7 0.13 4.6 0,09 o.os 0,02 < 0.01 0.02 < 0.01 0,6' 0&111\91 O,ll { 0.05 0.05 < 0.05 1'\11\91 6.9 0.12 3 0,05 0,05 0.02 < 0.01 < 0. 01 < 0.01 0.55 I 0 IHll\91 0.1 { o.os 0.02 < o.os 29\ 11191 , .1 0.1 2 0.39 G.05 o.o, < 0.0l 0.02 < 0.01 us 29\11191 G.39 < 0.01 < 0.01 < 0.0l t) 29\11191 0.31 < 0.05 0.03 0.03 Annqe 7.6 0.74 i!t .10 0.36 0.08 0.09 0. 10 0.03 0.03 0.8' " i) 04105192 u 0.12 188,B 0.32 0.03 0.05 0.07 0.03 0.04 o.31 l II 105192 6.7 0.11 m .1 0. 35 o.n o.o, o.oa 0.07 0.Oi 0.27 ~ 19105192 7.8 0.11 40 0.24 0.02 0.06 0.14 0.02 0.02 o.21 4 ) 15\06\92 7.8 0,11 12,1 0.12 0.02 0.06 0.12 0.02 0.02 0,19 7 24106\92 7.8 0.11 8.5 0.18 0.03 0.06 0.08 0.02 0.01 o.21 8 03107\92 7.1 0.33 0.04 0.04 o.u 0.01 0.01 07107\92 7.2 0.35 0.05 o.o, 0.07 0.02 0.01 16107\92 7.5 0.5' 0.18 0.04 0.12 0.02 0.02 Av1n91 7.3 0.11 98,1,t 0.30 0.05 0.05 0.09 0.03 0.02 O,N 4 - )

~ 1' ') I l BLE 5.4. I, HYAL OAK IIINES - YEllOIIKlllfE D1Vl510N - 0 UArot USE LICENSE - HISTORlCM. DAU ·, I Shti,n '3-1 CARBOII TANKS Chili~& Dtcantl 0

Sp1t, ' Tol•I Susp. Tobi Tel11 Tobi lohl Tobi hhl 0 P,91 6 pH Rn. Cl Coftd. S.lids As CN Cu Ni Zn Pb N\13/N l1t111. ~i 19/1 ■ s 19/I aqrt 19/1 aqll 19/1 aq/1 19/l 19/I deg . C ppll"' 26/06187 7.1,5 o.o, 2,55 2.90 0.84 0.70 0.26 0.31 0.06 < 0.10 5.10 15 • 2'1/0&/87 7,70 0.09 2.95 1,90 0,72 0.0 0.37 0.29 0.07 < 0.10 4.'IO 19 09107187 7.50 1.50 2.90 1.70 0.73 0.22 0.31 0.11 0.04 < 0.02 5.00 17 13/07/87 2.50 3.24 1.30 M2 0.30 0.26 0.08 0.04 < 0.02 5.15 20 • 20/07187 '·'°8.05 1.90 2.85 1,60 0,49 0.16 0.03 0.21 0.04 < 0.02 5.25 19 27/07187 7.10 2,50 3.2G 1.30 0.33 0.10 t 0.02 0.17 0.02 < 0.02 5.70 19 04/08/B7 7,90 uo 3.05 uo G.29 0,14 0.04 0.20 0.03 0.06 5,60 18 • 12108187 7.35 2.80 2.90 0.90 o.28 0.21 0.08 G.22 0.03 0.06 3.'l(l 15 17/09/87 8.20 2.70 2.95 1.20 0,25 0,22 0.02 0.28 0.02 0.05 6.80 15 26/08/87 7.86 2.80 us 1.50 0.18 0.36 0.04 o.38 0.01 0.02 uo 14 • 31/08/87 7.95 3.00 2.49 2,80 0.24 0.37 0.19 0.42 0,09 o.o, 6.20 12 08/09/87 7.60 6T 3 uo 1.40 0.17 0.23 0. 01 0. 39 0.04 < G,01 6.'10 11 14109187 1.75 6T 3 2.65 1.10 0,20 U7 0.03 0-47 0.02 0.03 6.BO II • 21/09/87 7.9S &T 3 2,75 I.SO 0.18 0.26 0.06 0.53 0.06 0.02 6.70 28/09187 7.60 6J3 2.65 1.70 0.28 0.19 0.15 0-44 0.02 0,04 6.20 8' 0 05/10/87 7.50 2,5() uo 1.20 uo 0,33 0,07 0.50 0,02 0.04 1,,60 6 19/10187 6.90 61 3 2.55 I. 70 0.20 0.52 0.10 0,71 0.02 0.04 6.00 0 03/11/87 us 0,40 2.0S 0,92 2,76 1.84 0.89 o.~ 0.03 6.20 1 0 20111187 u o 0.20 2,80 0.80 0.24 2,90 2.30 1,17 0.02 0.03 5.80 0 Annpe 7.56 1,36 2.7'5 1.55 0.38 0,59 0,32 G.41 0.04 0.03 5.85 12 0 1988 No Dischr9, frD■ hilin9s Pond due tD O~trdion of TRP

H\06\89 8,1 0.01 0.15 5.96 0,38 0.30 0,07 0.20 0.02 0.12 0.18 20 0.04 0 19\06\89 7.7 0.02 0.17 3.70 0.29 0,30 0,06 0.17 0.0, 0.05 0.13 17 0.08 2'\06\89 ,.; 0.01 1.58 5.80 0.70 0,33 0.10 0,05 0,06 0.08 0,18 IS 0.05 04\07\89 7.9 0.06 1,90 s.oo o.s, 0.28 0.21 0.29 0.06 0.06 0,19 16 0.05 0 10\07\Bi 7.7 o.o~ 2.05 us G,31 0.30 G.21 0.23 0.05 0.12 0.20 19 0.06 17\07\89 6.0 0,05 1.39 11.70 0.80 0.49 0.37 0,26 0.20 0.14 0-28 23 0.06 21107\89 7.9 0,1),1 I.SO 6.00 0.60 0-45 0.44 t.20 0.06 0,18 0.20 19 0.03 0 29107\89 7.9 0.05 1.45 5.1 0,70 0,38 0,40 0.44 0.06 0.18 0.25 18 01\08\89 8.2 G.03 1.,. 6.50 0.80 0.26 0.25 0.30 0.04 O.OB 0.18 20 0.05 0B108189 8.2 o.os 1.80 4.00 0.75 0,43 0.50 0.23 o.o, 0.06 0.17 22 0.07 ' '.) 14108\89 7.9 0.07 2.25 3.78 0.70 0.72 0.38 0.19 0.06 0.06 0.21 23 0.04 21108189 8.0 0.09 1,90 4,10 0.80 0.70 MS 0.30 0.08 0.06 o.35 11, o.o, 28108189 8.1 0.07 2.00 5.00 0.77 0.78 G.47 0.26 0.06 0.08 0.42 14 0,070 u 05109189 7.9 0.07 uo 4.20 0.79 0.43 o.50 MO 0.08 0.0B o.38 16 o.o,o ll\09\89 7,9 0.08 2.00 ,.20 0.80 0.58 U6 G.50 0.06 0.08 0.36 12 0,040 18109\8'1 7.9 0.09 z.oo U i o.n 0,65 0.55 0. 50 0.06 0.06 0.35 10 o.o,s '· ) 25109\89 s.o 0.09 1.90 4,10 0.78 0.60 MS 0.30 0.08 0.06 0.35 16 0.053 02110189 7.9 0.08 2.15 3.40 G.68 Q.48 G.48 0.31 0.06 0.07 0.31 5 o.°'s 10110189 7.9 0.08 i!.10 3.atl 0.60 o.,s 0.50 0.44 o.os o.os 0.30 Rver191 7.9 0,06 • J .72 '·" 0.66 0.'7 0,36 0.29 0.06 0.09 0.26 II, 0.051 0

: '

: )

~ ~ \._. •.l E 5.4.1. ROYM. OAK IIINES - YELLDVkNIFE DIYISlllll u 0 WATER USE LICENSE - HISTORICAi.. DATA Shtion 43-1 CARBON TAIIKS It.Hin!• DtranU 0

i hid Spec. Susp. Tohl hhl Tohl lolil lohl lohl P•pe 7 oM Rn. Cl Cond. Sol ids As CN Co Iii Zn pt Nll3/N Ttsp. Hp • ■o/1 •S 11/l •oll ., 11 •oil .,11 19/1 '!II ■o/1 d,9. C ppb f•~ 22\05\90 7.8 I. 7 12,73 0,33 0.38 0.8 0,54 0.06 8.02 0.28 9 • mOS\90 8,1 0.34 0.39 o.s 0.52 0.02 o.08 28\05\90 8 1.7 11.5 0.6B u 0.62 O.SI 0,06 0.12 0.35 13 05\06190 9.2 1•• II 0,61 0.48 0..8 0.3 0.05 0,13 o.~ 13 • 15106\90 7 1.s 9.5 0.4 0.0B 0,44 0.5 0.04 0.12 ue J3 momo 7,B 1.6 9 o.61 M 0.5 0.44 0.06 0.18 U3 13 < 0.10 21\06190 8.2 0.56 o.96 0.7 M8 0.06 O.H • 26\06190 8.2 1.9 8.5 UI 0.12 0.85 0.47 0.08 0.04 0.64 18 03\07\90 8.3 2 8 0.74 0..2 0.58 0.44 0.06 0.08 0.94 19 < 0.10 09\07\90 8.2 2.2 7.67 1.28 0.56 0.6 0.38 0.06 0.08 0.94 20 • 16\07\90 B 2.2 9.47 o.97 0,48 0.74 0.51 0.06 0,18 0,91 16 20107\90 B O.B2 0.32 0.4 MB 0.06 0.12 C, momo 7.9 2.2 7 0.?4 0.36 0.26 0.48 0.04 0.06 0.9 18 01\0B\90 8 2.2 6.1 0.41 M4 0.12 0-46 0.04 0.06 0.94 19 0?\08\90 7,7 u 6.63 (J.72 0.37 0.26 0.29 M4 0.06 0.93 18 < 0.10 0 H\08\90 7.9 2.2 5.2 o.85 0.51 0.4 0.42 0.06 0.1 0.92 18 21\08\90 7,9 2.2 6.8 1.2 UB 0.36 0.4 0.06 o.oe 0.92 15 28\08\90 7.8 2.25 4.99 0.72 0.69 0.54 0.5 0.06 0.08 0.92 .. 0 06\09\9(1 7.9 2.2 s.1 0.75 M7 0-98 0.68 0,08 0.12 o.t 13 < 0.10 10\09190 8.2 2 5.6 0,79 G.49 M 0,72 0.08 0.1 0.91 9 18\09\90 7.8 u 7 0.76 U3 0-42 0.52 o.o, 0,06 0.9 10 0 25109\90 8 2,1 7,1 0.85 0.7 0.58 0-48 0.06 0.08 0.9 10 02/10/90 8 2 7.5 0.84 0,65 0.64 o.58 0.06 0.08 O.SB 5 10\10\90 7.6 2 7.8 0.72 0.8 0.58 0.7 0.08 0.18 O.BB 3 < 0.10 0 18\10\90 8.1 t.t 7.66 0.71 0.63 0.64 0.7 0.06 0.14 0.96 3 ~.. .,,. 7,9 2.00 7,81 0.72 0.56 0.56 0.50 0.06 0.10 0.79 13 0

0

0

0

0

·)

0

)

.,.. ,... •, .,l BLE 5,4.I. ROYAL 0111( KINES· Y£UDIIKNIF[ Dl9lllill - UATER USE ll£EIISE • HISTIIIUCAL DATA 0 ' SbtioR 43•1 CAR8611 TAHKS lbili!M]& Otuntl 0

j Johl Sptt, Su,. Tol1I Tot1l Toh) Tohl Told Total ,.,, 8 ~H Ru. Cl CDnd, Solids As CN Cu Mi 2n Pb 111131N hll!'• "'-' • 11!11 •S ag/1 19/1 19/1 ag/1 10/I IDII ao/1 10/) dtg, C ppb G 30105\'1 8.1 0,27 0,19 0.22 0.28 0.06 0.1 • OH06\91 8.3 I 8.1 M2 0.1 0.12 U 4 0.04 0.08 0,21 15 11\06\91 8.1 o.85 1.9 G.43 0.1B 0.2 0.22 0.06 0.1 O.ZI 15 IB\0"91 t.3 1,3 a o.51 0.21 0.12 0.36 0.06 0.08 0.24 18 • 18\06\91 u 2 0.5 0.1 0.13 0.19 ( 0.01 ( 0.01 25\06\91 8.3 1.6 7.5 0.49 0.16 0.16 0.3 0.06 0.12 0.26 18 02107\91 u 1.8 7.8 0.35 0.26 0.14 0.24 0.0B 0.08 1.67 21 • 09\07\91 8.5 1.6 6.3 0.41 0.11 o. 12 0.24 0.04 0.06 1.5 15 15\07\91 8.6 1,6 6 1.03 0.19 0.14 o.~ 0.04 0.06 1.35 20 23107\91 8.4 1.1 u o., 0.2 0.14 0.22 o.o, 0.09 1.3 21 • 30\07"1 8.6 1,6 6.5 0.64 0,24 0.OB 0.22 0.06 0.06 1.2 21 (" 06\08\91 a.s I .7 s.e 0.59 o.22 O.OB 0.24 0.04 0.08 1.3 20 13\08\91 u 1,8 4 0.34 0.22 0.06 0.2 0.02 1.2 20 • 19\08\91 8.4 1.7 3.3 o.~ 0.08 0.1 0.24 0.04 0.0B u 19 21\08\91 G.69 0 27108\91 8.4 J.7 M 1.04 0.09 0. 12 0.14 0.03 < 0.05 1.95 14 27\08\91 U9 ') 04109\91 8.6 1.6 2 0.79 0.11 0.18 0.18 0.06 ( 0.05 2.1 12 0 10\09\91 8.6 1.6 2.8 0.69 0.12 0.18 0.29 < 0.02 < 0.05 u 9 I0\09\91 0.44 0 Average u 1.54 5.0 0.55 0,16 0.13 0.24 0.04 0.04 1.19 17 0 06107\92 8.2 0. 76 0.08 0.12 o.oa O.C2 0.02 ' U\07\92 8.35 0.7 0.11 0.055 0.13 0.01 0.03 0 21107\92 8.15 0.73 ~-13 0.07 0.17 0.02 0.02 hu191 8.2 0.73 0.11 0.08 0,13 0.02 0,02 0

{ " \ ,, 0

,')

0 u

I)

0

0

~ J J Royal Oak Mines Inc. i Figure 5.4.1. Tailings Decent - CN Cone 3.2

3 + 2.8 + 2.6

2.4 2.2

2 Cl 'E 1.8 z 1.6 0 C 1.4 +' ~ 1.2

1 + 0.8 - +· ~ ++ +i+ 0.6 + + i+-++* if. + +++"4-F- 0.4 + .;- ++ + .... + ~+ 0.2 + -tr4f+ +tt1'ff+" -t +++ ++* .,. 0 ,- 1987 I 1989 I 1991 1988 1990 1992 1987 through 1992 + Tailings Dec cnt Mex Avg Allowable Mex Grab Allowable r: Royal Oak Mines Inc. Figure 5.4.2. Boker Creek - CN Cone '4..------,

D 3.5

3

2.5 Cl D 'E z 0 2

0 +' ~ 1.5

D 1

[j □ 0.5 □ D C

.~w D.... ,fjljflp; 0' IW-IO '11111 ~ iii'□ 1989 1988 1990 1992 1987 through 1992 D Beker Creek -- Mex Avg Allowcble - Mex Greb Allowable

... Royal Oak Mines Inc. Figure 5.4.3. Tailings Decant - ks Cone 1.7' 1.6 1.5 1.4 1.3 + 1.2 + 1.1 Cl "'E + + 1 + -~ 0.9 + ~ + + ~ 0.8 C ''¥++ :t- 0 + + + +++-t -4- ~+ t- 0.7 + + ++ + * + 0.6 + + +it ++ + 0.5 + 4'r- + + + 0.4 + + + *+ + + -tt- 0.3 + ++ ~+ + + + 0 . .2 +-ih--H-

0.1 I I 1987 I 1989 I 1991 . 1988 1990 1992 1987 through 1992 + Tailings Decant Mex Avg Allowable Mox Grob Allowable .. V\ Royal Oak Mines Inc. Figure 5.4.4. Beker Creek - As Cone 1.7' 1.6 1.5 1.4 1.3 1.2 D 1.1

CJI 'E 1 C 0.9 ·- D ~ 0.8 a - fflP □ CeP 0 0.7 ~D Dc51 15 D e r '21 □ 0.6 D Cg] D '21 ~ t!Rn a 0.5 □ [ID □ 0.4 □ @ IID D ~i:P D D □ cP@ 0.3 □ □ □ D □ D CfoDleJe D 0.2 D Do□ □ IIDD □□ D Do Do! □ ~ D □ D f§tJ D 0.1 ~ra,@QJ 1ljJ Lfil cf.! o□'cP□ D 0 1987 1989 1991 1988 1990 1992 1987 through 1992

□ Beker Creek Mex Avg Allowable Mex Greb Allowable w... Royal Oak Mines Inc. Figure 5.4.5. Tailings Decant - Cu Cone 2.6

2.4 I + 2.2

2 1.8 L +

Cl 1.6 'E ·-C 1.4 :::, (.) 1.2 .....0 0 1 I- 0.8 ~ ++ + 0.6 I- + * +.* +.I +* 0.4 I- +'~ :+- -Ft.+ + ++ !i- +t + 0.2 I- ++ *+ ++ * -(¢+ -tt1" +N--ttt+ ol I I 1987 I 1989 I 1991 * 1988 1990 19'92 1987 through 1992 + Tailings Decent Mox Avg Allowable Mox Grob Allowable w.., ) Royal Oak Mines Inc. I Figure 5.4.6. Boker Creel< - Cu Cone. 2.1 2 1.9 □ 1.8 1.7 1.6 1.5 □ 1.4

C'I 1.3 'E 1.2 ·-C: 1.1 u:i 1 C 0.9 □ () ..... 0.8 0.7 0.6 0.5 □ 0.4 %~ %~ □ 0.3 a 'rJ □ □ £ i~ □ C£J 0.2 □ ~ 0.1 flif!f!jJ L..J...,.-4-lliftlftm 0 ~ 1989 1991 1988 1990 1992 1987 through 1992

□ Beker Creel< Mex Avg Allowable Mex Greb Allowable

...,_ Royal Oak Mines Inc. Figure 5.4.7. Tailings Decant - Pb Cone 0.45 ..------=------i

0.4

0.35

0.3

Cl 'E 0.25 .0 Cl

0 0.2 ~ I ~ + ++ + 0.15 ~ + + ++ -A- + + 0.1 t ++ -++ + + -Hf- -++++++ + * ** -+t-+ + -Hr ~ + -t++ 0.05 J- + + * + +*-++ + + ++ ++ I + 0 1987 I 1989 I 1991 1988 1990 1992

+ Tailings Decent Max Avg Allowable Max Grab Allowable t Royal Oak Mines Inc. Fi~ure 5.4.8. Boker Creek - Pb Cone OAS' ~

0.4

0.35

0.3

'-01 E 0.25 .0 Q...... 0 0.2 ~ 0.15 □ D D a 0.1 D □ D OOl•II IID □DJ □ □ tD IIDlID D tD cm IIDIIIII □ 0.05 □ win~ DD aljl □ciJ tID c:P□ ~□ r!JD□ ~ □ IID c:fl □ □ tD CllJ cmn □ IID □□ mo □ □ □ o:n □ o I ooommo 1 □ 111@W ~ □ IIIl □ □ 1 IID□ 1 ° □ IJIHBEBIIIB ~ 1 1987 1989 1991 1988 1990 1992

□ Boker Creek Mox Avg Allowable -- Mox Greb Allowable

-£ ROYAL OAK MINES INC. I Figure 5.4.9. Boker Creek - Ni Cone 1.2

1.1 □

1

0.9 □ 0.8 □

Cl 'E 0.7 C ·- 0.6 □ ·-z □ c:P □□ 0 0.5 B 0 □ I- □ 0□□ 0.4 □□ ~ %tp 0 □ e 0.3 □ □ 'a DD lei c:P□ □ □ 0.2 actP G¥i□ cPcm □ □ dJ[§b 'd a 0.1 □ □ □ i§b □ □ D'cJ cfJ □ D □ dJ @[j§J le? □ □ ~ ci,n& ,q 0 I □p9,T'~ 19~9 1987 I 1991 1988 1990 1992 1987 through 1992 D Boker Creek Max Avg Allowable -- Max Grab Allowable

, ~ J ROYAL OAK MINES INC. Figure 5.4.1 O.Tcilings Decent - Ni Cone 1.3' 1.2 + 1.1

1

0.9 +

0.8 "C"I E + C 0.7 -t -tt ·- z 0.6 + C + + o + +1 \ I+ t- 0.5 ~ + +:+- ++ + ++ +. 0.4 I- + + :+- ++ ++ 0.3 I- +++ -t + + ++ + ~ + + + +++ t**++­ 0.2 ~ +-t + ++ + ++ + + + + 0.1 + + + + 0 1 . 1987 1989 1991 1988 1990 1992 1987 through 1992 + Tailings Decent Mox Avg Allowable Mox Grob Allowable

~ $ ROYAL OAK MINES INC. b Figure 5.4. 11. Beker Creek - Susp Solid 40

350 D

300

01 I D 'E 250 r ·-C □ 5'l "C t= I D 0 (/) 200 I D Q. 5'l :::, (/) 150 ....0 ~ D 100 ~ □ D D □ D D □ □ 50 ~ r-, -D

------______7ej""

0 I 1987 I 1989' I 1991 I 1988 1990 1992 1987 through 1992 D Boker C~ek Mox Avg Allowable -- Mox Grob Allowcble ) ROYAL OAK MINES INC. Figure 5.4. 12. Tlgs Decent - Susp Solid 32' 30 28 26 24

01 22 "E C 20 ·-,, 18 1J ·-0 (/) 16 0. Pl 14 :::, + (/) 12 + 0 4- +' 0 10 I- ~ + 8 \ z •-t -t:...+--f+l 6 ++ -t -f ~ + + +_/- 4. ++~ + + + -I++ 2 f- + ~++ 0 1987 1989 1991 1988 1990 1992 1987 through 1992 + Tailings Dec cnt -- Mox Avg Allowable -- Mex Greb Allowable

s I" ROYAL OAK MINES INC. , Figure 5.4. 13. Measured pH 10 r------

9

~ !+- * -+++ +ifu + + ++ 8 + .L+ □+++ ml?51 □ ....5'J ++ ~ D □ am ·-c ::::, -t~+~ □ 'ti :t □□ DD □ I D C. mlj. □ □ [I]] 8JC1:l □ DD 7 %an~ ac B ~□ + +.B- 'tP pollil □ a □ □ 11D □ 'fi:J'Tm ~ [DJ □ D □ 6 □

SL------

1987 through 1992 D Boker Creek + Tailings Decent Min Allowo ble pH -- Mox Allowable pH

.c 1,1