The investigation into last week’s drinking water scare in parts of Scottsdale and Paradise Valley has expanded to include Motorola, potentially leaving the electronics giant open to federal fines, environmental officials said Wednesday.

Meanwhile, Arizona American Water Co. — the private utility with whom Motorola contracts to treat groundwater pumped from a local Superfund site — is considering what to do with up to a half-million gallons of potentially contaminated water in a reservoir underneath its treatment plant.

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Motorola is one of four companies charged with dumping TCE into Scottsdale’s groundwater supply beginning in the 1950s. Motorola hired Arizona American to pump and treat that groundwater, and could be held responsible for mishaps, Takata said.

• Who came up with 20 ppb and how was it derived? Remember, this is the supposed level of contamination that snuck into the system last week as reported by the polluters' consultant. Any possibility it was actually higher?


• Why would Motorola knowingly approve a single-point-of-failure emergency communication system that, by design, excludes 35% of its contractors' customers?