Cal. PEN § 4019.1

(a) Notwithstanding any other law, the sheriff or county director of corrections may, at his or her discretion, award additional time credits to any inmate sentenced to the county jail who participates in an in-custody work or job training program other than those specified in Section 4019.2, and who is eligible to receive one day of credit for every one day of incarceration pursuant to Section 4019. The sheriff or county director of corrections may instead award one and one-half days of credit for every one day of incarceration while satisfactorily participating in work or job training subject to this section.

(b) As used in this section, a work or job training program includes, but is not limited to, any inmate working on an industrial farm or industrial road camp as authorized in Section 4101, an environmental improvement and preservation program, or projects such as forest and brush fire prevention, forest, brush, and watershed management, fish and game management, soil conservation, and forest and watershed revegetation.