Water tank installation for Robin Lane sewer spill residents continued Monday, with 29 tanks now installed. Testing continues, withabout 75% of impacted properties tested. Officials reported 65 wells sanitized. Wells are declared safe after two negative E. coli and coliform tests, 24 hours apart. City Manager Alan Flora has hired a hydrologist to study the effects of the spill on the aquifer. A town hall is set for 6 p.m. tomorrow at Clearlake City Hall.