San Francisco Chronicle: Fed up with the encroaching sprawl, Linda Jimenez fled Silicon Valley for Tracy in 1990 in search of more affordable housing and the small-town way of life of her Santa Clara County youth. Eventually, the sprawl caught up. In 1990, Tracy, a friendly agricultural community separated from the Bay Area by the Altamont Pass, had fewer than 34,000 residents. Today, the mushrooming town, located at the western gateway to the Central Valley, has a population nearing 81,000. The town …