A p r i l 2014 C a n adi a n M inin g J o ur n a l 2 3 Po r t a b le Powe r WE DO MORE THAN DE SIGN E QUIPMENT WE PO WER Y OUR SUC C E S S At Doos an P o r t ab le P ower were known for engineering solution s th at m a k e customers more productive Visit www Doos anPor tablePower c om to nd the de aler ne arest y ou and nd out ho w w e c an help y ou ac hiev e M ax imum f uel ec onom y Unpa rallel ed pr oductivity R e gion s pec i c emi s s ion s so lution s Doo s anP or t ab l eP o w er c om 8007278457 2014 Doo s an Infr ac or e P or t ab l e P o w er Suffcient service life and dur ability Integrity of the caps must not be reduced as a result of annual freezethaw cycles corrosion acid rock drainage and other hazards over a design life of 200 years Remote access Many mines are in remote locations Specifcally for the mines in the Ura nium City area bulk materials are shipped to the area over a winter ice road or in the open w ater months via barge F rom Uranium City the access roads to the mines in many cases have long since deteriorated Access to some of the mines included in Project CLEANS is by boat only So any solution must be construct ible without use of readymix cement trucks large cranes or other conveniences av ailable in less remote areas Due to road conditions loads are typically restricted to a maximum width of four metres Pr event unauthorized access In order to maintain public safety the installed caps must stand up to unauthorized access De pending on the type of minerals mined at the site and current industry demands the future may see prospecting and exploration for ore left behind Climate change Caps must be designed for the possibility of more extreme weather increased precipitation including snow loads and more dramatic temperature changes F or est Fir es Wildfres are inevitable in the boreal forest As such the caps must be able to withstand the intense heat of a fre Additional loading V egetation may cause organic buildup Large animals may pass over the caps T here may be snowmobiles and other vehicles driving over the caps It is foreseeable that exploration and mining may return to the area as well All of these loading scenarios must be tak en into consideration when de signing the caps Reduced feld ftting A more robust de sign process reduces the requirement for feld ftting during installation However the design has to be fexible to accommodate un avoidable alterations when unexpected site conditions are encountered In cases of very irregular rock surround or installation chal lenges feld ftting will be required and must be incorporated into the design Economically effective As the mine sites in Project CLEANS and other abandoned non uranium mine sites are the responsibility of the provincial government there is a need to safeguard taxpayers dollars Life cycle con siderations meant a need to minimize future replacement or repair costs W ith all of these factor s combined car e is r equir ed in or der to r educe the degr ee of uncertainty in the fnal design Design fac tor s such as cost r educing feld ftting dur ing installation and tr ansport and access to the sites can be anticipated However the futur e climate longterm human activity in the ar ea or even whether r ecor ds contain ing the mines locations will be available to futur e gener ations ar e consider ations that must be factor ed into the fnal cap design PROJECT NEEDS Initially the Saskatchewan government in conjunction with a local Ur anium City contr ac tor implemented stainless steel caps attached to the historic mine shaft collar s or sur r ounding bedr ock These initial designs used lar ge quantities of expensive stainless steel as well as r equiring extensive feld ftting in some cases Seeking a less expensive solu tion with an acceptable service life SRC commissioned McElhanney Consulting Services Ltd Design consider ations included SOLUTION T o addr es s t h e a f o r em en t io n e d co n sider a t io n s a c le a r def ini t io n o f t h e desig n cr i t er i a wa s j o in t l y un der t a k en b y S R C a n d M cE l h a nn e y C o n s u l t in g S er v ices Th e y t h en e va l u a t e d s e v era l c los ur e m a t e r i a l s in c l udin g u l t ra hig hp er f o r m a n ce co n cr et e UHPC a l umin um w e a t h er in g s t e e l ga l va nize d s t e e l s t a in les s s t e e l a n d p o l yur et h a n e f o a m PUF B a s e d o n t h e desig n cr i t er i a s t r uc t ur a l l y r einf o r ce d s t a in les s s t e e l p l a t e c u s t o mf i t t e d t o e ac h min e o p enin g wa s c h os en a s t h e p r ef er r e d m et h o d f o r t h e si t es in c l ude d in t h e 2013 f ie ld s e a s o n Th e c a ps w er e m a n ufac t ur e d o f fsi t e t o en s ur e t h a t a p p r o p r i a t e q u a li t y co n t r o l m e a s ur es w er e a va i l a b le a s w e l l a s t o e limin a t e s hi p m en t o f ext ra m a t er i a l t o t h e p r o j e c t si t es S e v era l o f t h es e c a ps h a v e n o w b e en in s t a l le d Th e desig n p r o ce d ur e s t a r ts w i t h a si t e in v es t iga t io n t o o b t a in t h e dim en sio n s o f t h e o p enin g a n d t o det er min e t h e a t t ac h m en t p o in ts o f t h e c a p Th e d a t a p o in ts