The science GPA for admitted students claiming CA residency for 2009 was 3.58. I would imagine that the BCPM GPA for UCs to be somewhere between 3.6-3.7.
Source:
http://www.aamc.org/data/facts/applicantmatriculant/table21-mcatgpastatemat09.pdf
Keep in mind, science GPA is highly variable based on major and courses taken (lower division courses tend to have lower GPAs and stricter curves, science majors tend to have higher science GPAs based on more science classes taken and easier curves in upper division courses, et cetera).