The selected firm(s) will provide as needed, on-call professional environmental consulting services, as needed, which include but are not limited to those described herein. The County will assign work to any of the firms as is deemed necessary and appropriate by the County. All Service Providers and subconsultant(s), employees or agents thereof, performing work per agreements awarded under this RFP, must have at all times throughout the duration of their performance of the work, all appropriate, valid license(s) required under law to provide the work being performed. If the possession of any license(s), including but not limited to a valid California professional license, registration, or certification (e.g. Professional Engineer, Professional Geologist, or other applicable) appropriate for the environmental consulting services to be provided, is required under law for the performance of the work, the service provider shall ensure that the work is performed by, or under the an direct supervision of, an appropriately licensed individual. No sub-consultants shall be utilized without prior authorization by County.