California Code, Health and Safety Code - HSC § 78605

(a) During the term of the prequalified list, as specific projects are identified by the department as being eligible for contracting under the procedures adopted pursuant to Section 78610, the department shall contact the highest ranked firm on the appropriate prequalified list to determine if that firm has sufficient staff and is available for performance of the project. If the highest ranked firm is not available, the department shall continue to contact firms on the prequalified list in order of rank until a firm that is available is identified.

(b) The department may enter into a contract for the services with a firm identified pursuant to subdivision (a), if the contract is for a total price that the department determines is fair and reasonable to the department and otherwise conforms to all matters and terms previously identified and established upon participation in the prequalified list.

(d) Once a satisfactory contract is negotiated and awarded to a firm from any prequalified list for a generic project category involving a site or facility investigation or characterization, a feasibility study, or a remedial design, for a specific response action or corrective action, including, but not limited to, a corrective action carried out pursuant to Section 25200.10, the department shall not enter into a contract with that firm for purposes of construction or implementation of any part of that same response action or corrective action.