▁was ▁created . ▁Most ▁of ▁the ▁nit ro gen ▁and ▁more ▁than ▁half ▁of ▁the ▁ph osph orus ▁st ems ▁from ▁settlement s ▁in ▁the ▁area , ▁while ▁all ot ments - g ard ens , ▁generally ▁lack ing ▁se wers , ▁cont ributes ▁with ▁nut ri ents ▁and ▁indust ries ▁and ▁others ▁operations ▁cont ributes ▁with ▁z inc ▁and ▁co pper . ▁ ▁Sed iments ▁have ▁high ▁levels ▁of ▁co pper ▁and ▁nick el , ▁and ▁deeper ▁sed iments ▁contain ▁very ▁high ▁levels ▁of ▁organ ic ▁comp ounds ▁such ▁as ▁PA H s ▁and ▁PC B . ▁ ▁Im ages ▁ ▁Flora ▁and ▁fa una ▁ ▁In ▁late ▁sum mers , ▁the ▁lake ▁is ▁domin ated ▁by ▁various ▁cy an ob acter ias . ▁ ▁The ▁only ▁zo op l ank ton ▁recorded ▁are ▁rot if ers . ▁ ▁No ▁invent ory ▁of ▁aqu atic ▁plants ▁have ▁been ▁made ▁since ▁ 1 9 7 6 , ▁but ▁the ▁lake ▁shares ▁are ▁domin ated ▁by ▁re ed ▁with ▁water ▁l il ies ▁found ▁in ▁the ▁southern ▁part . ▁ ▁Ten ▁fish ▁species ▁were ▁recorded ▁in ▁ 1 9 9 7 - 1 9 9 8 , ▁including ▁per ch , ▁northern ▁pi ke , ▁car p ▁b ream , ▁and ▁pi ke per ch . ▁ ▁Sign al ▁c ray fish ▁is ▁occasionally ▁found ▁in ▁the ▁lake . ▁ ▁The ▁most ▁commonly ▁bre eding ▁bird ▁m all ard ▁is ▁accompanied ▁by ▁E uras ian ▁co ot ▁and ▁great ▁cr ested ▁gre be .