Discharge from The Dalles Wastewater Treatment Plant into the Columbia River returned to compliance within permitted limits for E. coli on Sunday morning.   According to The Dalles Public Works Department, the average of five samples taken throughout Saturday at the City discharge point to the river were within limits.  A 24-hour incubation time is required for test results to be finalized.  Recent Columbia River samples show that E. coli levels at the sample locations were well below bacterial criteria set by the Oregon Department of Environmental Quality for freshwater recreation.  Signs which were placed at locations of public river access on the Oregon shore of the Columbia River to warn of contaminated water were taken down on Sunday.