This document discusses Building Regulation Part C, which relates to resistance to moisture. It covers topics like floodwater entering buildings, rising groundwater, sub-soil drainage, floors, walls (both internal and external), and roofs. Guidance is provided on assessing land affected by contaminants as set out in Appendix A of Approved Document C. Measures for treating, containing, and removing contamination are also outlined. The document recommends reviewing CLR 11 for the assessment process of contaminated land and provides contact information for inquiries on Part C.