Further study indicates that this may represent a failed attempt to probe for further quarry sources (since to the North in Area A, the bedrock crops up much higher and closer to the topsoil than in this southern section). It may also simply be evidence of a later shoring up and packing of wall 1058.
Layer of larger chunks of tufo within fill in cut 1113, which follows the wall 1058 and a cut bedrock feature on eastern side. Fill within SU 1113.