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Keywords from Image Description:
TRICKLING FILTERS AT THE BACK RIVER SEWAGE TREATMENT PLANT THIS IS THE PRIMARY TREATMENT FACILITY FOR THE BALTIMORE AREA NARA .tif Scope and content General notes Local identifier DA Environmental Protection Agency NARAAuthor Pickerell Jim Photographer File TRICKLINGFILTERSATTHEBACKRIVERSEWAGETREATMENTPLANTTHISISTHEPRIMARYTREATMENTFACILITYFORTHEBALTIMOREAREANARA