N.J. Stat. Ann. § 44:7-16

The county clerks or registers of deeds and mortgages, as the case may be, shall record in a book to be known as "reimbursement agreements" the said certificates, and shall make a complete alphabetical index to the same, and no clerk or register shall charge any fee therefor. Whenever a county shall have received satisfaction for such judgments, the county welfare board shall enter an acknowledgment of satisfaction upon the record of said judgments, without charge.