It shall be unlawful to locate, erect, construct, reconstruct, alter, enlarge, extend, convert or relocate any building, structure or sign or use any building, structure, land or sign in violation of the provisions of this chapter or amendments or supplements thereto lawfully adopted by the County Board of Supervisors. It shall also be unlawful to fail to obtain permits as required by this chapter or to fail to comply with any requirement or condition imposed by the Board of Adjustment or Land Management Committee.