MONROVIA (AP) — Another step has been taken toward further expansion of Los Angeles County’s growing commuter rail system.

Foothill Gold Line Construction Authority directors this week approved advanced engineering plans for a 12.3-mile extension of the light-rail system to the city of Montclair on the eastern edge of the county.

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The extension’s cost is estimated at $1.2 billion. Most of the funds would come from a half-cent sales tax measure on the November ballot.

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The most recent previous Metro Rail expansion was westward. In May, a 6.6-mile extension of the Expo Line opened to Santa Monica, linking the system to the seaside. The line was immediately swamped with riders.

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