FOLSOM, Calif. (AP) — A massive project to modernize medical record-keeping for California prison inmates has more than doubled in cost from original estimates to nearly $400 million in just three years.

The federal court-appointed receiver who controls California’s inmate health care system approved the project in 2013 to replace the state’s antiquated paper-based records with an electronic system that can track the medical and mental health care of nearly 130,000 inmates.

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But it now won’t be installed at all 35 prisons until the end of 2017. Inmate advocates may seek to push it back even longer at some troubled prisons.

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An Associated Press review shows the cost ballooned in part because the first estimate left out several basic needs.

The receiver says the biggest hurdle was a virtually unusable pharmaceutical records system.

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