The department is responsible for regulating the movement of oversize and overweight vehicles and loads on certain public roadways in this state, in order to ensure the safety of the traveling public, and to protect the integrity of the public roadways and the bridges. This responsibility is accomplished through the issuance of permits for the movement of oversize and overweight vehicles and loads. The sections under this chapter prescribe the policies and procedures for the issuance of permits and the filing of surety bonds. All applications for permits and all questions regarding the permits should be directed to the department, even though TxDOT is responsible for certain issues regarding permits.