10 0 2 01 9 S U S T AINABILITY REPOR T Monit oring and e v aluation T SM T ailing s Manag ement P r ot oc ol T ailing s Guide and O per ation Maint enanc e and Sur v eillanc e Guide E ach sit e has c onduct ed a r e vie w ag ains t the pr ot oc ol and guidanc e and de v eloped a c orr e sponding action plan t o implement impr o v ement s Geot echnic al and en vir onment al monit oring W e c onduct r egular monit oring at our t ailing s w at er w as t e r ock and he ap le ach f acilitie s W at er and s oil qualit y monit oring O per ations monit or do wns tr e am w at er and s oil qualit y t o ensur e c omplianc e with pr edictiv e models and w at er qualit y r egulations W as t e monit oring W e monit or w as t e g ener ation and dispo s al at all oper ations A c c ount abilit y O ur V ic e P r e sident o f Miner al P r oc e s sing T ailing s D ams o v er s ee s the perf ormanc e o f our critic al f acilitie s O ur P erf ormanc e T a ili n g s F a c ilit i e s M a n a g e m e n t T ailing s ar e the b y pr oduct s o f pr ecious and b as e met al or e pr oc e s sing and miner al and met al e xtr acting T ailing s ar e cr e at ed aft er the or e is mined and hauled t o a pr oc e s sing plant wher e it is crushed gr ound and pr oc e s s ed in w et slurr y t o e xtr act pr ecious or b as e met als using le aching or fot ation The r e sidual nonec onomic gr ound r ock is the t ailing s T ailing s f acilitie s ar e us ed t o s t or e the t ailing s and allo w s ep ar ation o f w at er f or r ec y cling or dis char g e T ailing s ar e s t or ag e with one o f the f ollo wing c onfgur ations Subaerial Abo v e gr ound s t or ag e f acilitie s wher e t ailing s ma y be in slurr y thick ened or p as t e f orm with an int ernal pond o f cle ar w at er D r y s t ack plac ement is another t ype o f subaerial s t or ag e wher e w at er is s ep ar at ed b y thick ening and fltr ation be f or e dr y t ailing s ar e plac ed int o a s t ack Subaqueous Under w at er s t or ag e wher e t ailing s ar e entir ely submer g ed within an e xis ting pond T ailing s f acilitie s ar e o ft en b as ed on a dam s tructur e which c an be c ons truct ed using up s tr e am c ent erline or do wns tr e am methods or c ombination o f the s e methods All t ailing s dams begin with a s t art er dyk e which is r ais ed periodic ally as t ailing s ar e depo sit ed in the f acilit y In up s tr e am c ons truction the dam is r ais ed with the cr e s t mo ving up s tr e am o v er in the depo sit ed t ailing s In c ent erline c ons truction the dam is r ais ed v ertic ally fr om the s t art er dam In do wns tr e am c ons truction the dam is r ais ed b y shifting the cr e s t do wns tr e am o v er s tructur al fll on the do wns tr e am f ac e