(1) The Commissioner shall maintain every monument in respect of which the Government has acquired any of the rights mentioned in section 4 or which the Government has acquired under section 10.
     (2) When the Commissioner has accepted the guardianship of a monument under section 4, he shall, for the purpose of maintaining such monument, have access to the monument at all reasonable times, by himself and by his agents, subordinates and workmen, for the purpose of inspecting the monument, and for the purpose of bringing such materials and doing such acts as he may consider necessary or desirable for the maintenance thereof.