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ROAD CONSTRUCTION PLAN – KENO CITY BYPASS ROAD
KENO HILL SILVER DISTRICT MINING OPERATIONS
QML‐0009
REVISION 1
November 2012
ROAD CONSTRUCTION PLAN – KENO CITY BYPASS ROADQML‐0009
Keno Hill Silver District Mining Operations NOVEMBER 2012
KHSD_ROAD_CONSTRUCTION_PLAN‐KENO_CITY_BYPASS_ROAD_NOV2012 I
TABLE OF CONTENTS
1 INTRODUCTION ................................................................................................................................................................ 1
2 SITE DESCRIPTION ............................................................................................................................................................ 1
2.1 HISTORY ...................................................................................................................................................................... 12.2 GEOLOGY .................................................................................................................................................................... 22.2.1 PROPERTY GEOLOGY .................................................................................................................................................. 22.3 GENERAL ENVIRONMENTAL CONDITIONS ........................................................................................................................... 52.4 LIGHTNING CREEK ......................................................................................................................................................... 6
3 ROAD DEVELOPMENT OVERVIEW ........................................................................................................................................ 6
3.1 ONEK ACCESS BRIDGE .................................................................................................................................................... 6
4 SITE PREPARATION ........................................................................................................................................................... 7
4.1 CLEARING .................................................................................................................................................................... 74.2 HERITAGE RESOURCES PROTECTION ................................................................................................................................. 7
5 ROAD DESIGN AND SPECIFICATIONS ..................................................................................................................................... 7
5.1 HAUL ROAD SPECIFICATIONS ........................................................................................................................................... 75.1.1 HAUL ROAD DESIGN CRITERIA ...................................................................................................................................... 85.1.2 HAUL ROAD CONSTRUCTION GUIDELINES ....................................................................................................................... 95.1.3 HAUL ROAD MAINTENANCE ......................................................................................................................................... 95.1.4 HAUL TRUCK CLEANLINESS ........................................................................................................................................ 105.2 ACCESS TIE‐IN AND STAGING AREAS ............................................................................................................................... 105.3 ACCESS CONTROL ....................................................................................................................................................... 105.3.1 TEMPORARY ACCESS CLOSURE.................................................................................................................................... 105.3.2 PERMANENT ACCESS CLOSURE ................................................................................................................................... 11
6 BORROW SOURCES ........................................................................................................................................................ 11
7 GEOCHEMICAL EVALUATION ............................................................................................................................................ 11
8 GEOTECHNICAL TESTING .................................................................................................................................................. 11
ROAD CONSTRUCTION PLAN – KENO CITY BYPASS ROADQML‐0009
Keno Hill Silver District Mining Operations NOVEMBER 2012
KHSD_ROAD_CONSTRUCTION_PLAN‐KENO_CITY_BYPASS_ROAD_NOV2012 II
9 BEST MANAGEMENT PRACTICES ....................................................................................................................................... 12
9.1 ENVIRONMENTAL MONITORING .................................................................................................................................... 12
LIST OF FIGURES
Figure 1 Keno City Bypass Road Routing and Access Management ............................................................................ 14Figure 2 Conceptual Road Design ................................................................................................................................ 15Figure 3 Typical Conceptual Road Section ................................................................................................................... 16Figure 4 Typical Bridge Design ..................................................................................................................................... 17
LIST OF TABLES
Table 1 Keno Hill District Environmental Setting Summary ........................................................................................... 5Table 2 Road Design Criteria .......................................................................................................................................... 8Table 3 Design Vehicle Volvo A30E ................................................................................................................................ 9Table 4 Road Construction Best Management Practices ............................................................................................. 13
ROAD CONSTRUCTION PLAN – KENO CITY BYPASS ROADQML‐0009
Keno Hill Silver District Mining Operations NOVEMBER 2012
KHSD_ROAD_CONSTRUCTION_PLAN‐KENO_CITY_BYPASS_ROAD_NOV2012 1
1 INTRODUCTION
AlexcoKenoHillMiningCorp. (Alexco) continues todevelop themineral resources of theKenoHill SilverDistrict(KHSD).AspartofKHSDMiningOperations,AKHMwillcontinuetoestablishaccessandhaulroadsonthesite.Thisplanisintendedtoaddressconstruction,operation,andmaintenanceofsiteroadsdevelopedinsupportofAKHMminingactivitiesandwillbeadaptedasnecessaryfortheconstructionofspecificroads.Temporaryandpermanentclosureofroads isaddressed in theKenoHillSilverDistrictMiningOperationsReclamation and Closure Plan. The scope of this plan includes specifically the Keno City Bypass Road toaccommodateminetrafficassociatedwithLuckyQueenandOnekminingoperations.
2 SITE DESCRIPTION
TheKHSDlieswithinthetraditionalterritoryoftheFirstNationofNa‐choNyakDun(FNNND)andnearthecommunitiesofKenoCityandMayo.TheKenoHillSilverDistrict is located incentralYukon(63°54'32"N,135°19’18”W;NTS105M/14&105M/13),354kmduenorthofWhitehorse.AccesstothepropertyisviatheAlaska, Klondike and Silver Trail Highways from Whitehorse to Mayo and an all‐weather gravel roadnortheastfromMayotoElsa(45km);atotaldistanceof452km.
TheKHSD is locatedonandaroundGalenaHill,KenoHill andSourdoughHill.Theproperty lies along thebroadMcQuestenRivervalleywiththreeprominenthills tothesouthof thevalley.LuckyQueenis locatedapproximately4kmnortheastofKenoCityandOnekissituatedabout500mnortheastofKenoCity.
TheKenoCityBypassRoadroutingisshowninFigures1and2.TheBypassRoadisrequiredtoaccommodatemine traffic associatedwith the LuckyQueen andOnekmine sites. Its routingdivertsmine traffic aroundKenoCityratherthanthroughthecommunity.
2.1 HISTORY
TheKenoHillareawasoncehosttooneoftheworld’srichestsilverdeposits.In1903,thevillageofMayowasestablishedandthefirstsilverclaimwasstakedbyJacobDavidsononGalenaCreeknearpresentdayElsa.In1918KenoHillwasstakedandclaimedafterthediscoveryofasignificantsilverdeposit(Yukoninfo,n.d.).Asilverrushoccurredinthedistrictandin1919JohnKinmanfoundasilverveinaroundLightningCreek.Hiscabinbecameastoppingpointandeventually,KenoCity(YukonDevelopmentCorporation,2004). In1921the Treadwell Yukon Mining Company was formed, investing in various properties in the area. Elsa wasclaimedin1924,onGalenaHillbyCharlieBrefault.Itwasnotdevelopeduntil1935afterthemillwasmovedtothevicinity.In1947theUnitedKenoHillMinesLimited(UKHM)tookovertheTreadwellproperties,andbeganusingtheElsamilltoprocessore.ThedistrictwaslaterconsolidatedbyUKHMandUnitedKenoHillMineralsLimited(collectively“KenoHill”).
Together they became the second largest silver producers in North America and the fourth largest in theworldduring the late1950s.TheElsacommunitygrewtoapopulationofapproximately700 in the1980sduringthisboom.UnitedKenoHillMinesLtd.waseventuallyforcedintobankruptcyin1989duetothefallofmetal prices. The propertywas declared abandoned in 2001. In 2005 Alexco purchased the assets of the
ROAD CONSTRUCTION PLAN – KENO CITY BYPASS ROADQML‐0009
Keno Hill Silver District Mining Operations NOVEMBER 2012
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UKHM and United Keno Hill Minerals Limited, collectively becoming “United Keno Hill Mines Limited(UKHM)”.TheYukonGovernmentapprovedthepurchaseagreementinDecember2007followingthereceiptofpermitsandapprovals.
2.2 GEOLOGY
The Keno Hill Silver District is located in the western part of the Selwyn Basin in an area dominated bydeformedandmetamorphosedUpperProterozoictoMississippiansedimentaryrocksformedattheedgeofacontinentalmargin. During the Jurassic andCretaceous, the areawas subjected to compressional tectonicforcesproducing twomajor thrust sheets (Robert Service andTombstone) andwidespread folding. Earlylargescaledeformationproducedrecumbentfolds,resultinginlocalstructuralthickeningofstrata.Asecond(andpossiblythird)deformationaleventproducedgentlesouthwesterlyplungingsyn‐andantiformpairs.
TheRobertServiceThrustSheetinthesouthiscomposedofLateProterozoictoCambriansandstone,locallywith interbedded limestoneandargillite,aCambriantoMiddleDevoniansuccessionofsiltstone, limestoneandchert,andUpperDevonianargillite,chert,andchertpebbleconglomerate.Thelatterunituncomfortablyoverliesthelowerunits.
The Tombstone Thrust Sheet to the north consists of Devonian phyllite, felsic meta‐tuffs and metaclasticrocks, overlainbyCarboniferousquartzite. This latter rockunit is locally thickeneddue to folding andorthrustingandhoststhemineralizationoftheKenoHillSilverDistrict.
Intrusive rocks formed during four episodes of plutonism. Early Paleozoic fine‐grained diabase occurs asmetre‐scale dikes and sills in the Upper Proterozoic to Lower Cambrian rocks. During the Mid‐Triassic,gabbros todiorites formedpodsofvarioussizes,primarily in theDevonianandMississippianrocksof theTombstonethrustsheet. Athirdphaseofplutonismtookplacearoundninety‐twomillionyearsagointheearlyCretaceousandresultedinwidespreadandvoluminousTombstoneintrusionsofcommonlygranitictogranodioriticcomposition. Theyoungestmagmaticactivityoccurredaroundsixty‐fivemillionyearsago intheUpperCretaceousandresultedintheformationofperaluminousmegacrysticpotassiumfeldspargranite.
Inadditiontowherepolymetallicveinswereexploited,theareahostsanumberofoccurrences,andshowingsof tungsten, copper, gold, lead, zinc, antimonyandbarite. Tin, tungsten, andmolybdeniteoccurrencesarepossibly related to the suite of Cretaceous intrusion, whereas lead, zinc, and barite occur in stratiformcalcareoussedimentaryrocksofearlytomid‐Paleozoicagetypicalofsediment‐hosteddeposits.
2.2.1 Property Geology
TheKenoHill District is underlain primarily by YukonGroupmetasedimentary rocks, locally divided intothree formations;UpperSchist,CentralQuartziteandLowerSchist. TheUpperSchist (HylandGroup,pre‐CambriantoCambrianage)overliesthequartzite inwhat is inferredtobeathrustcontact(RobertServiceThrust) and consists of quartz‐mica schist, quartzite, graphitic schist and minor limestone. The CentralQuartzite (Keno Hill Quartzite, Mississippian age) contains thick‐and thin‐bedded quartzite, massivequartzite, graphitic phyllite, graphitic schist, calcareous schist andminorTriassic greenstone. This unit isapproximately 700m thick and is host tomost of the past producing ore bodies. Structurally juxtaposedbelow the quartzite is the Lower Schist which has been correlatedwith the Devonian‐Mississippian Earn
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Group.TheLowerSchistincludesgraphiticschist,argillite,thin‐beddedquartzite,calcareousschist,phyllite,slate,sericiteschist,minorthick‐beddedquartziteandlocallysignificantintervalsofTriassicgreenstone.Thegreenstone forms sillsand/orboudinsand consistsofmetadioriteandmetagabbro. Thesills andboudinsformbodiesuptoonekilometrelongandthirtymetresthick.Regional,greenschistfaciesmetamorphismofallunitsisbelievedtohaveoccurredintheMiddleCretaceous,about105millionyearsago.
Anumberofquartz‐feldsparporphyriticsillshaveintrudedthestratigraphyparalleltoschistosity.ThesillsaremostcommonintheLowerandUpperSchistsandcanreachthicknessesofuptofiftymetres;reportsofoccurrencesintheCentralQuartziteareinconclusiveandvague.Thequartz‐porphyrysillsarebelievedtobeofCretaceousage.
Structurally, the property is characterized by four sets of faults; many of which have been filled byhydrothermal minerals, forming veins. The oldest fault set consists of south dipping structures that aregenerally parallel to foliation and are apparently associated with the Tombstone Thrust Fault sincemovementwascontemporaneousorslightlylater.Locally,brittledeformationhasbeenobservedalongthesestructures.Asecondfaultset,knownas“longitudinalveins”strikesnortheasttoeastnortheastanddips
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steeplysoutheast.Thelatestmovementalongthesefaultsissinistralwithoffsetslocallyreachingmorethan150 metres; however, more than one episode of movement commonly is indicated. Depending on thecompetencyofthehostrock,longitudinalveinscanbeuptothirtymetreswideinananatomisingsystemofsub‐veins. Essentially allmineralized rockwasmined from these longitudinal veins. A third set of faults,knownas“transversefaults”,isnorth‐weststrikinganddipssteeplytothenorth.Transversefaultstypicallydo not contain silver and lead mineralization but are commonly filled by quartz with trace to minorarsenopyrite,pyriteandjamesonite.
Ayoungersetoffaults,knownascrossfaults,strikenorthtonortheastwithadipofsixtydegreeswesttosouthwestandoffsetveinorlongitudinalfaultsbyupto2,000m.Inthewesternpartoftheproperty,dextralmovement is the most recent event along these structures, whereas in the eastern part of the propertysinistralmovementwithlessmagnitudeprevails.
AtKenoHill, the largest accumulation of oreminerals occurred in structurally prepared competent rocks,suchastheCentralQuartzite,resultinginareasofincreasedfluidflow.Incompetentrockslikephyllitestendtoproducefewerandsmaller,ifany,openspaces,limitingfluidflowandresultingmineralprecipitation.
Mineralization in the KenoHill Silver District is of the polymetallic silver‐lead‐zinc vein type. In general,commonganguemineralsincludemanganiferoussideriteandtoalesserextentquartzandquartzbrecciaaswell as calcite and other carbonates. Silver occurs in argentiferous galena and argentiferous tetrahedrite(freibergite).Insupergeneassemblages,silverisfurtherfoundasnativesilver,inpolybasite,stephanite,andpyrargyrite.Leadoccursingalenaandzincinsphalerite,whichisiron‐rich.Othersulphidesincludepyrite,arsenopyrite(locallygold‐bearing)andchalcopyrite.
The veins of the Keno Hill Silver District display characteristics associated with both mesothermal andepithermaldepositsanditisnotclearifacontinuumexistsorifseparateanddistinctmineralizingeventsareinvolved.Themostprominentexamplesofepithermalstylemineralizationarefoundinthewesternpartofthedistrict,althoughtheLuckyQueenmineonKenoHillproducednativesilverandrubysilverinquantity.Proximitytoamagmaticheatsourcehasoftenbeencalledupontoexplainthedistrictzonation,thoughthisisbynomeansacompleteexplanation.
Mineral zonation is common within base metal‐rich veins (zinc‐rich margin and silver/lead‐rich center).Changesinmineralogywithinindividualoreshootsislessclearlydocumented,althoughtherehaslongbeenaconvictionthatsilverand leadrichzonesoccurhigher in theveinswhilezincbecomesdominantatdepth.Anecdotalevidencesuggeststhatverticallystackedoreshootsmayrepeatedlyshowzoningofleadrichupperportionstozincdominantroots,butdataconfirmingthishasnotbeenfound.Ingeneral,Pb‐Znmineralizationappearstobenearlycontemporaneousinage.
Mechanismstriggeringdepositionoforeandganguemineralshavebeensuggestedbydistrictwidestudiesoffluidinclusionsandlightstableisotopes. Fluidboilingappearstohavebeenubiquitousandsomeevidenceexists for fluid mixing. The hydrothermal fluids responsible for mineral deposition contained significantquantities of CO2 which may have “boiled” during abrupt changes in pressure produced during fluidmovementfromconfinedfracturestomoreopenconduitsformedinquartzite.
ROAD CONSTRUCTION PLAN – KENO CITY BYPASS ROADQML‐0009
Keno Hill Silver District Mining Operations NOVEMBER 2012
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Irrespective of stratigraphic formations or regionalmap units only a fewmajor rock types are commonlyencounteredintheareaoftheoldmineworkings.Theseare:
schistsandphylliteswithvariablecarboncontent;
chloriticphyllitesorschists;
quartzitesandphylliticquartzites;
sericite‐quartzphyllites;and,
greenstones.
2.3 GENERAL ENVIRONMENTAL CONDITIONS
Table 1 summarizes existing environmental conditions in the KenoHill project area. The KenoHill SilverDistrictlieswithintheYukonPlateau–NorthEcoregion,justsouthoftheWerneckeMountains.Theterrainconsistsofconcordant,rolling,uplandareasseparatedbywidevalleys.Alpinemountainpeaksextendabovetheuplandslocally.Manyvalleysincludepeatlands,palsas,fensandmeadowsofsedgetussocks.Upperslopesmaybecoveredwithscreematerial,withtreelineoccurringat1,350to1,500m.Theareahasbeeninfluencedbythelatestglaciationbutshowsmoresubtleevidenceofanearliereventaswell.
Table 1 Keno Hill District Environmental Setting Summary
Drainage Region Stewart River drainage region
Significant Watersheds McQuesten River, Lightning Creek and Stewart River Watershed, Mayo River
Ecoregion Yukon Plateau (North)
Study Area Elevation 900‐1350 m asl (Above Sea Level)
Vegetation Communities Northern boreal forests occupy lower slopes and valley bottom; spruce, pine and alder; grasses and sedges, mosses occupy forest floor; heavy moss and lichen growth resident as ground cover understory of shrub willow; open and forest fringe areas of willow and scrub birch, and various flowering plant species.
Wildlife Species Moose, grizzly and black bear, caribou, beaver, wolf, lynx, marten, wolverine, western tanager, magnolia warbler, white‐throated sparrow, bald eagle, furbearers and small animals.
Committee on the Status of Endangered Wildlife in Canada (COSEWIC) listed species include: Common Nighthawk (Threatened); Rusty Blackbird and Olive‐Sided Flycatcher (Special Concern).
Fish Species Bering and Beaufort Sea salmonids and freshwater species, including: Arctic grayling, Arctic char, lake trout, trout perch, lake whitefish, broad whitefish, burbot, inconnu, Arctic Cisco, Northern pike, slimy sculpin
ROAD CONSTRUCTION PLAN – KENO CITY BYPASS ROADQML‐0009
Keno Hill Silver District Mining Operations NOVEMBER 2012
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2.4 LIGHTNING CREEK
Lightning Creek is situated within a narrow valley with a steep gradient flowing from the north side ofSourdoughHill intoDuncanCreek,whichdrains intotheMayoRiver.HopeandThunderGulches flow intoLightningCreekwithintheboundsoftheKenoHillSilverDistrict(KHSD).LightningCreekhasalsobeenthesite of extensiveplacerminingupstreamofKenoCitybothhistorically andatpresent time.TheLightningCreek drainage has also been affected by localized quartz mining activities including the Bellekeno Minewhichwasre‐openedbyAlexcoin2011.MineaditdrainagesfromBellekeno625(northsideofSourdoughHill) and Keno 700 (south side of KenoHill) eventually report to the Lightning Creek drainage. LightningCreekisnotableasitistheonlylargewatershedintheKHSDnotconnectedtotheSouthMcQuestenRiver.LightningcreekdrainsintotheDuncanCreekwatershedwhichflowssouthintotheMayoandStewartRiver.
3 ROAD DEVELOPMENT OVERVIEW
TheKenoCityBypassRoadwillbedevelopedfromtheWerneckeRoad,crossingSignPostRoad,alongthehistoricOnekpowerline,totheOnek990Portal,crossingLightningCreekRoadandtheOnekAccessBridgeacrossLightningCreek to theBellekenoHaulRoad.TheBypassRoadwillbea single‐lane radio‐controlledroad,approximately2.1kmlongand6–9mwide.Someportionsoftheroadwillbewideenoughtosafelyaccommodate passing mine traffic. It will be developed with cut/fill construction, using the fill materialsupplemented by some additionalN‐AMLwaste rockmaterial (~15,000m3 in total required). TheN‐AMLwasterockwillbesourcedfromOnekorBellekeno.InitialdevelopmentoftheBypassRoadmayrequireN‐AML from the historic Onekwaste dump adjacent to the Bypass Road, until sufficient volumes of N‐AMLmaterialareavailablefromtheOnek990declinedevelopment.
Theroutingdoesnotcrossorcomewithin30mofanywatercourseorwaterbodyotherthanattheapproachtoLightningCreekandattheOnekaccessbridge.Ditchingalongtheroadwillfacilitateappropriatedrainage.Culvertswill be installed at the intersectionswithWernecke Road, Lightning Creek Road, BellekenoHaulRoadandSignPostRoadfordrainage.Additionalculvertsmaybeestablishedalongthebridgeapproaches.Theclearedvegetativedebrisandtopsoilwillbestockpiledalongtheroutinginnaturalclearedareasforroadreclamation.
3.1 ONEK ACCESS BRIDGE
TheKenoCityBypassRoadroutingincludescrossingLightningCreek,whichwillrequireinstallationofthebridge.AKHMproposestoinstallaclearspan(singlespan)bridgeacrossLightningCreek.Thebridgewillbea single‐lane, steel girder prefabricated bridge, approximately 9m long and 4.4m wide. The bridge isdesigned tohave the flowcapacityof a1:100year floodevent; itwill be capableof supportingminehaultraffic(atleast100t).AnengineeredtypicalLightningCreekbridgedesignisprovidedinFigure3.
A6.5mwideaccessroadwillbeestablishedonthenorthandsouthsideofLightningCreektothebridgesite.Twooverflowculvertswillbe installedwithin the1:100year floodeventzone.Fillmaterial for theaccessroadandabutmentswillbesourced fromOnekandBellekenoN‐AMLwasterock. Thebanksandriparianareawillbeclearedwithabrushmowerorpushedasidewithadozer.
ROAD CONSTRUCTION PLAN – KENO CITY BYPASS ROADQML‐0009
Keno Hill Silver District Mining Operations NOVEMBER 2012
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TheproposedsitefortheclearspanbridgedesigncrossingwasselectedbyAlexcoengineeringpersonnelandinconsiderationofriparianandflowregimeconditions.
Bardusan Placers Ltd. holds the placer claims at the site of the proposed Onek Access Creek Bridge. Theplacer rights holder has been contacted with respect to bridge location. The placer claim owner is notcurrentlyoperatinganyplacerminingactivityontheclaimsattheproposedbridgecrossinglocation.
AKHMinstalledaclearspanbridgeonLightningCreek,approximately1.1kmdownstreamoftheproposedOnekAccessBridgesite(TypeBWaterLicenceMS10‐029).PursuanttotheNavigableWatersProtectionAct,Transport Canada determined that Lightning Creek is a Non‐Navigable waterway at the location of theexistingbridge(seeemailfromTransportCanada–YORDocument2009‐0030‐120‐1).Itwasdeterminedtobenotnavigablebecausethereisaculvertupstreamoftheexistingbridge.TheproposedOnekAccessBridgeislocatedapproximately586mupstreamoftheculvert.
TheOnekAccessBridgewillbelicencedunderanamendmenttotheexistingMS10‐029.
4 SITE PREPARATION
4.1 CLEARING
Ingeneral,adozerwillbeusedforclearing.Anexcavatorwillbeusedasrequired.Theroadroutingdoesnotcomewithin30mofawatercoursewiththeexceptionoftheapproachesandcrossingLightningCreek.Banksandriparianareaswillbeclearedwithabrushmowerorchainsaw.Treeswithin10mofLightningCreekwillbeclosecutandstumpsleftinplace.
4.2 HERITAGE RESOURCES PROTECTION
Theroadroutinghasbeenground‐truthedbyAlexcoofficialsandaknowledgeablecommunitymember.NoheritageresourceswerelocatedwithintheroadROW.Alexco’sHeritageResourcesProtectionPlanforKenoHillSilverDistrictMiningOperationswillbeapplied.
5 ROAD DESIGN AND SPECIFICATIONS
5.1 HAUL ROAD SPECIFICATIONS
Allhaulroads,BellekenoHaulroad,LuckyQueenHaulroad,andtheKenoCityBypassroadwillbesubjecttoPart 15.42 and 15.43 of the Yukon Occupational Health and Safety Regulations, which set out minimumdesign criteria for safety considerations. In addition, mine haul road design guidelines developed by theUniversityofAlberta(TannantandRegensburg,2001)andwhichwerereferencedduringthedevelopmentoftheroadplans.
ROAD CONSTRUCTION PLAN – KENO CITY BYPASS ROADQML‐0009
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5.1.1 Haul Road Design Criteria
CivildesigncriteriaforhaulroadsweredevelopedbyWardropEngineeringInc.basedonapplicablefederalandterritorialcodesandregulations,aswellasindustrystandardsandotherreferencedocuments(AppendixDoftheConstructionSitePlan,Revision1).TheroaddesigncriteriaareshowninTable2.ThedesignvehicleusedasthebasisofdesigncriteriaisshowninTable3.Figure4showsatypicalroadcross‐section.
Table 2 Road Design Criteria
Haul Road
Operating Width* 5.881 or 8.822 m
Design Speed 50 km/hr
Cross fall 2%
Maximum Grade 8%
Surface 200 mm
Base 300 mm
Sub‐base 500 mm
Cut Side Slope 1.5 : 1
Fill Side Slope 2 : 1
Subgrade Compaction >80%
Granular Compaction >85%
* Excludes berms and ditches on both side of haul roads. 1. One way traffic. 2. Two way traffic (passing).
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Table 3 Design Vehicle Volvo A30E
Volvo A30E Dimension
Width 2.94 m
Length 10.3 m
Height 3.3 m
Wheel Base 2.216 m
Tire Pressure 267 kPa
Weight Loaded Empty
Gross Vehicle Weight 51 060 kg 28 000 kg
Front Axle 14 990 kg 12 500 kg
Drive Axle 36 070 kg 15 560 kg
5.1.2 Haul Road Construction Guidelines
Generalguidelinesforhaulroadconstructioninclude:
Haulroadsshallbeall‐weatherconstruction;
Safetybermwillbeconstructedonallfills>3.0m;
Heightofsafetybermwillbe1.25m(0.75xthediameteroftireonVolvoA30Earticulatedhaultruck);
Breaksinthesafetybermwillnotexceedthewidthofthebladeoftheequipmentconstructingandmaintainingthebreakstoallowfordrainageandsnowclearance;
Sideslopewillbemaximum2:1ifembankmentisbetween0‐3m;
Sideslopewillbemaximum1.5:1ifembankmentisbetween>3m;
Alternatingvehicularpull‐outswillbeusedateachendofonewaytrafficroadsegments;
Pulloutslengthequals1.5timesthevehiclelength;
Pulloutswidthequals1.5timestheoperatingwidth;and
A clearly marked emergency runaway lane or retardation barrier capable of bringing a runawayvehicletoastopwillbeprovidedandmaintainedbelowwhereroadgradeexceeds5%.
5.1.3 Haul Road Maintenance
Periodicgradingandresurfacingasdeemednecessarywillbeemployedinordertokeepthehaulroads ingoodrepair.Duringthewinter,haulroadswillbeplowedandsandedtoensurepropertractionismaintained.
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5.1.4 Haul Truck Cleanliness
Haul truckswill be subject to periodicmaintenance at theDistrictMill site. Thismaintenancewill includewashing,withcaretakenthatallwashwaterberecycledordirectedtothewatertreatmentpond.
5.2 ACCESS TIE‐IN AND STAGING AREAS
TheKenoCityBypassRoadwillintersectwithWerneckeRoad,SignPostRoad,LightningCreekRoadandtheBellekenoHaulRoad.
ExistingdisturbanceareasalongtheKenoCityBypassRoadtheOnek990PortalPadwillbeusedforstagingconstruction equipment andmaterial (e.g., N‐AMLwaste rock). Fuel will be stored in the designated fuelstorageareawithappropriatecontainmentontheOnek990portalpad.ExplosiveswillbestoredontheOnekhistoricwastedumpsinaccordancewithapplicableregulations.
Nofencingorgatingwillberequired.Thefollowingsectiondescribesaccesscontrolmeasures.
5.3 ACCESS CONTROL
Therewill be stop signs to stopmine traffic at the intersectionswithWerneckeRoad, SignPostRoadandLightningCreekRoad.Signagewarningofcrossingminetrafficwillbeinstalledinbothdirectionsfromtheintersection, in accordance with regulatory requirements. Appropriate line‐of‐sight distances will bemaintained to ensure crossing trucks and approaching traffic on theWerneckeRoad are able to see eachother. The line‐of‐sight distance requirements of YGHighways & PublicWorks Transport Branch and theHighway Access/Workswithin a Right‐of‐Way permits will be adhered to in order to ensure public andworkersafety.
Signagewarning of crossing/turningmine dump trucks (over the highway dump trucks)will be installedalongSignPostRoad,LightningCreekRoad,BellekenoHaulRoadandWerneckeRoadinaccordancewiththerequirementsanddirectionofYGHighways&PublicWorksTransportBranchofficials.
TheKenoCityBypassRoadisintendedforminepersonneluse.Nogateswillbeused.TheKenoCityBypassRoadwillbearadiocontrolledroadaccessibletominetrafficonly.Signswillbeinstalledattheroadaccesspointsprohibitingpublictrafficfromtravelingonit.Themaximumspeedlimitwillbe40km/h,reducedto20km/hatblindcornersandroadcrossings.
5.3.1 Temporary Access Closure
Tolimitaccessduringtemporaryclosure,pylonsandsignagewillbeusedtowarnroadusers,andgateswillbeinstalled,asrequired.Thebridgewillnotbedecommissionedduringatemporaryclosure.
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5.3.2 Permanent Access Closure
Thebridgewill remain inplaceduring the lifeof theproject (~15years).Decommissioningmeasureswillinvolveremovaloftheclearspanbridge,abutmentsandculverts.Theaccessroadswillbedecommissioned,regradedandre‐sloped.Alldisturbedareaswillbescarifiedandre‐vegetated.Thebankswillbestabilizedthroughrevegetationandstrategicplacementoftheexistingriprap.ThesedecommissioningmeasuresareincorporatedintotheReclamationandClosurePlan.
6 BORROW SOURCES
The Keno City Bypass Road fromWernecke Road to the bank of Lightning Creek at the bridge crossing(~15,000m3ofmaterial),andtheOnek990PortalPad(~4500m3ofmaterial)willbeconstructedwithfillfromthecutsandOnekN‐AML.Ifrequired,borrowmaterialfromthehistoricOnekwastedumpadjacenttotheBypassRoadwillbeusedforinitialdevelopmentuntilsufficientvolumesareavailablefromthedeclinedevelopment.
Bellekeno N‐AML waste rock will be used for constructing the section of access from the bridge to theBellekenoHaulRoad(~4,800m3).
AfterinitialdevelopmentandestablishmentoftheOnekAccessBridge,OnekorBellekenoN‐AMLwasterockmaybeusedformaintenance,upgradesorgeneralconstructionpurposes.
7 GEOCHEMICAL EVALUATION
TheKenoHill SilverDistrictMiningOperationsWaste RockManagement Plan (WRMP)will be applied toselecting N‐AML material appropriate for construction. Where blasting is required for road construction,material from the blast face will be sampled to ensure it meets the WRMP N‐AML criteria. If it doesn’tadaptivemanagementactionswillbetakentoaddresstherockexposure(e.g.shotcreting).
8 GEOTECHNICAL TESTING
AKHMengineersgroundtruthedtheroadalignmenttoensuregeotechnicalstabilityoftheroadbed.Someoftheroutingfollowsareasofexistinglineardisturbance(e.g.thehistoricOnekpowerlineROW).Totheextentpossible, routing with sufficient overburden underlain with competent rock was selected. Areas showingsignsofunderlyingpermafrost(stuntedtrees,groundslumping)wereavoidedtotheextentpossible.Inareasofpotentialpermafrost(e.g.portionofKenoCityBypassRoadsouthofLightningCreektotheBellekenoHaulRoad), ground protection measures, such as installation of additional road foundation material, will beapplied.RefertoTable4foradditionalmitigationmeasures.
ROAD CONSTRUCTION PLAN – KENO CITY BYPASS ROADQML‐0009
Keno Hill Silver District Mining Operations NOVEMBER 2012
KHSD_ROAD_CONSTRUCTION_PLAN‐KENO_CITY_BYPASS_ROAD_NOV2012 12
9 BEST MANAGEMENT PRACTICES
Table2outlinestheBestManagementPracticesthatAKHMwillapplytoroadconstruction,maintenanceandclosureactivitiesinordertoprotectenvironmentalconditions.
9.1 ENVIRONMENTAL MONITORING
In accordancewith clause53ofQZ09‐092, betweenMay andOctober of each year,Alexcowill inspect allunlinedwasterocklocations,whichinthiscaseapplytotheroadbecauseN‐AMLwasterockistobeusedasconstructionmaterial.Asperclause60,wasterockreportingrequirementsincluderecordingintheannualreport:
60.a)anyphysicalinstabilityincludingerosion;
b)upstreampondingofwateranddownstreamseepage;
c)thelocationofpondingandseepage;
d)thevolumeofflow,fieldpHandconductivityofpondingorseepage;
e) visual evidence of sulphide oxidation including snow melt areas or the presence of oxidationproducts;and
f)trendsinpH,andconductivityforanyrecurringseepageorpondinglocation.
TheAdaptiveManagementPlanstipulatesthatseepagefromallstructuresconstructedofN‐AMLwasterockshallbesampledforfieldpHandconductivityandflow.Additionalwaterqualityanalysisistobeconductediftheseepagequantityissufficient.
Todate,noseepshavebeendetectedfromN‐AMLwasterockstructures.
ROAD CONSTRUCTION PLAN – KENO CITY BYPASS ROADQML‐0009
Keno Hill Silver District Mining Operations NOVEMBER 2012
KHSD_ROAD_CONSTRUCTION_PLAN‐KENO_CITY_BYPASS_ROAD_NOV2012 13
Table 4 Road Construction Best Management Practices
Environmental Component Mitigation
Runoff, Sediment and
Erosion Control
The road will be graded to allow surface water to drain off the road. Any runoff that drains from the road surface or staging
areas will be conveyed into permeable roadside ditches and culverts and will likely infiltrate into the subsurface. During large
storm events it is expected that some runoff volume will reach lightning creek. It is expected this volume will not be large
enough to cause flooding issues downstream because the road area represents a very small percentage of the overall
watershed area.
As part of road maintenance, ruts that could be prone to erosion will be filled.
Vegetation removal will be minimized to the extent possible.
Water bars will be constructed to promote proper drainage, if required.
During bridge construction/ adjacent road development, temporary sediment control, such as silt fences or temporary
diversion berms, will be installed, monitored and maintained to prevent sediment runoff into the creek.
If minor rutting is likely to occur, stream bank and bed protection methods (e.g. swamp mats, pads) shall be used provided
they do not constrict flows or block fish passage.
Dust Control Application of water or non petroleum dust suppression agents will be employed if required to control fugitive dust from
haul road surfaces during the summer months. Run of mine ore from underground operations is generally wet, coarse
grained and free of fines and will not create dust.
Site Isolation During bridge construction and adjacent road development, banks and riparian areas will be cleared with a brush mower or
chainsaw. Trees within 10 m of Lightning Creek will be close cut and stumps left in place.
Culvert Installation An overflow culvert will be installed on each side of the bridge crossing within the 1:100 year flood event zone. These are to
be placed above the ordinary high water mark and therefor will not have any effect on Lightning Creek aquatic life. The
banks and riparian area will be cleared with a brush mower or chainsaw within 10 m of the stream bank. Stumps and root
systems will be left in place to preserve natural erosion protection. All other storm water management culverts will be
constructed to divert water beneath the roadway between road ditches and will not impact existing stream systems.
DRAWN BY MD
KENO CITY BYPASS ROUTING ANDACCESS MANAGEMENT
NOVEMBER 2012 VERIFIED BY KW
I:\Keno_Area_Mines\ONEK\Maps\2_Permitting\Traffic\Road_Construction_Bypass_Plan_20121114.mxd (Last edited by: jpan;11/14/2012/15:07 PM )
This map is for illustrative purposes only. This is not a legal document. Quartz claim boundaries are current as of March 26,2012. Placer claim boundaries are current as of Feb 26th, 2012. Land Disposition data obtained from Canada Lands SurveySystem, current as of March 2012. Site hydrography and contours derived from 2006 aerial imagery obtained from AeroGeometrics, Calgary Alberta. Aerial photograph obtained from Geodesy Remote Sensing Inc., Calgary Alberta. Imagery acquiredSeptember 13th and 14th 2006.Datum: NAD 83; Projection: UTM Zone 8N
ALEXCO KENO HILL MINING CORP.ONEK AND LUCKY QUEEN
KENO CITYDISTRICTMILL
EXISTINGLUCKY QUEEN
ADIT
TO BELLEKENOMINE
ONEK 990PORTALAND PAD
HISTORICONEK
400 ADIT
DUNCAN CR EEK ROAD
BELLEKENOHAUL ROAD
WERN
ECKE
ROAD
CHRIS
TAL LAKE ROAD
SILVER TRAILHIGH WAY
ChristalLake
E r i c k s o n G u l c h
INSET 1
INSET 2
INSET 3
484000
484000
485000
485000
486000
486000
487000
487000
7087
000
7087
000
7088
000
7088
000
7089
000
7089
000
7090
000
7090
000
7091
000
7091
000²
0 500 1,000250Meters
1:15,000 (when printed on 11 x 17)
FIGURE 1
This drawing has been prepared for the use of Access MiningConsultants Ltd.'s client and may not be used, reproduced or reliedupon by third parties, except as agreed by Access MiningConsultants Ltd. and its client, as required by law or for use ofgovernmental reviewing agencies. Access Mining Consultants Ltd.accepts no responsibility, and denies any liability whatsoever, to anyparty that modifies this drawing without Access Mining ConsultantsLtd.'s express written consent.
Existing Private Road, Haul Road
Proposed Private Road, Haul Road
Existing Public Road, Haul Road
Road Right of Way Watercourse
Waterbody
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1,000
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991
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KENO HILLSILVER DISTRICT MINING
OPERATIONS
Profiles derived from 1 meter contour data derivedfrom 2006 aerial imagery obtained from AeroGeometrics, Calgary Alberta.and Site hydrographyand contours derived from 2006 aerial imageryobtained from Aero Geometrics, Calgary Alberta.
NAD 83 UTM Zone 8N
L i g h t n i n g C r e e k
VENTRAISE
DECLINE ANDUNDERGROUNDWORKINGS
ONEK 990PORTALAND PAD
ONEK ACCESSBRIDGEK E N OK E N O
C I T YC I T Y
ONEK HISTORICAL WORKINGS
NOVEMBER 2012KENO
CITYBYPASS
ROAD
L IGHTNINGCREEK
ROAD
BELLEKENOHAUL
ROAD
A'
A
B'
B
0 m
100 m
200 m
300 m
400 m
500 m
600 m
700 m800 m
900 m1000 m
1100 m
1200 m
1300 m1400 m
1500 m
1600 m
1700 m
1800 m1900 m
²
I:\Keno_Area_Mines\ONEK\Maps\1_Overview_Maps\Specific_Topics\Roads\-ProposedRoad_20121119.mxd(Last edited by: mducharme;19/11/2012/15:19 PM )
This drawing has been prepared for the use of Access Mining Consultants Ltd.'s client andmay not be used, reproduced or relied upon by third parties, except as agreed by AccessMining Consultants Ltd. and its client, as required by law or for use of governmentalreviewing agencies. AccessMining Consultants Ltd. accepts no responsibility, and deniesany liability whatsoever, to any party that modifies this drawing without Access MiningConsultants Ltd.'s express written consent.
²
CONCEPTUAL ROAD DESIGN - PROFILE A
A A'
NOT FORCONSTRUCTION
LIGHTNING CREEKBRIDGE
JUNCTION WITHBELLEKENOHAUL ROAD
0 200 400100
Meters
0 200 400 600 800100Meters
Profile A Distance Markers(distance in meters)
Profile A
Profile B
Existing Roads
CONCEPTUAL ROAD DESIGN - PLANCONCEPTUAL ROAD DESIGN OVERVIEW
FIGURE 4CONCEPTUAL ROAD
DESIGN
CONCEPTUAL ROAD DESIGN - PROFILE B
B
B'
ONEK 990PORTAL
ORIGINAL GROUND PROFILE H:V = 3:1
ORIGINAL GROUND PROFILE H:V = 3:1
EL
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(IN
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TR
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IN M
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DISTANCE (IN METRES)
DISTANCE (IN METRES)