CONCORD -- The Mt. Diablo school district teachers' union announced Tuesday it has reached a tentative three-year contract agreement that would provide for salary hikes and increased benefits contributions through 2016.

If ratified later this month, the district would pay $6,390 toward medical coverage for one person or $12,781 toward coverage for two or more people starting in January 2015. The following year, the district would pay $16,615 annually toward family medical coverage. Those who opt out of medical coverage would receive in-lieu payments of $100 per month.

The agreement includes a 3 percent raise retroactive to July 1, 2013; a 2 percent raise effective in February 2015; and a 4 percent raise effective in February 2016. In addition, teachers would receive two professional development days starting in 2014-15.