1#重庆人 + N3 P/ R5 Y- s& X9 A1 x * j# c& D3 r) Z$ K; F) \ & b7 H7 n2 o7 {: Q w( U0 {If the builder is responsible for rough grading and the certificate as per your contract signed, then for sure, your builder has to do whatever needed to get a pass, whether it is a retaining wall or anything else. Talk to your lawyer to find out.