Notwithstanding any provision of the general statutes, the Commissioner of Transportation may enter into an agreement with the owner or operator of a public service facility, as defined in section 13a-126, desiring the longitudinal use of the right-of-way of a state highway to accommodate trunkline or transmission-type utility facilities and to fix the terms, conditions and rates and charges for use of such right-of-way; provided, no such agreement shall exempt a public service facility from the provisions of chapter 277a. In the case of public service companies, as defined in section 16-1, such charges or rates shall not exceed the actual administrative, construction, operation and maintenance costs of the department incurred as a result of the public service company’s use of a nonlimited access state highway. The department may estimate such charges or rates and require prepayment of such charges or rates, provided any amount in excess of the actual amount shall be refunded to the public service company.