There are no special documents required for service on the federal government other than that which is required by California law. However, in order to avoid a failure to honor a support earnings withholding order by the agency served, the creditor should provide the sheriff with a certified copy of the judgment showing that it is for alimony or support in addition to the original writ and application for earnings withholding order.
Federal law requires service by certified or registered mail, return receipt requested, or by personal service, upon the appropriate designated agent or the head of such agency, if no agent has been so designated. The process shall be accompanied by sufficient information to permit prompt identification of the employee and the payments involved. The agent for service shall respond within thirty days after the date effective service and shall, as soon as possible but not later than fifteen days after the date effective, send written notice to the affected employee at the employee’s duty station or last-known home address. (5 USC §5520a)
The earnings withholding order should include the full name, social security number and date of birth, if available and, in the case of military personnel, the branch of service, rank or grade, and if known, the name and location of current duty station.
It is the responsibility of the creditor to provide the name and address for service. The authorized agents for service of wage garnishments are listed in the Code of Federal Regulations, Title 5, Parts 581 and 582, Appendix A which is available on the internet.