Owner shall participate on a pro rata basis in the cost of the improvements to be installed. Agreement Between Contra Costa Community College District and the United Faculty 2022-2025.Deferred Compensation. This Addendum is intended for use in the unincorporated portions of Contra Costa County. The Contra Costa County Employees' Retirement Association ("CCCERA") invites organizations to submit proposals on providing IRC 457(b) Deferred.