N.J. Stat. § 27:23-17
The Department of Transportation is hereby authorized in its discretion to expend out of any funds available for the purpose such moneys as may be necessary for the study of any transportation project or projects and to use its engineering and other forces, including consulting engineers and traffic engineers, for the purpose of effecting such study and to pay for such additional engineering and traffic and other expert studies as it may deem expedient, and all such expenses incurred by the department shall be paid by the department and charged to the appropriate transportation project or projects, and the department shall keep proper records and accounts showing each amount so charged. Upon the sale of transportation revenue bonds for any project or projects, the funds so expended by the department in connection with such project or projects shall be reimbursed by the Authority to the department from the proceeds of such bonds.
Any obligation or expense hereafter incurred by the Department of Transportation with the approval of the Authority for traffic surveys, borings, preparation of plans and specifications, and other engineering services in connection with the construction of a project shall be regarded as a part of the cost of such project and shall be reimbursed to the State out of the proceeds of bonds herein authorized.
N.J.S. § 27:23-17