Locus 3 was the first extension of T108. It was a 1x3 meter extension to the north of the original trench boundaries, along with a 2 meter by 2 meter square precisely northwest of the northwestern corner of the original trench; in total, Locus 3 measured 7 square meters. Locus 3, like Locus 1, 5 and 10 is a topsoil deposit containing heavily abraded tile and pottery. The one notable find deriving from this locus is a medieval pottery fragment, indicating the locus was not secure. The soil in this locus was dry, crumbly and moderately compacted. Locus 3 bordered a stump from Loci 1 and 2 in the SE2 corner and featured a consistent amount of thin roots and had many small rocks varying in size from 5 to 15 centimeters scattered across the top, which became less frequent the deeper Locus 3 was excavated.

Soil from Locus 3 was excavated using pickaxes, hand axes and removed with shovels into buckets, then into wheelbarrows where it was hand sorted. Usually, pickpasses in this locus were thrown simultaneously, with one person beginning in the northwestern corner, moving southeast, axing in the two by two meter portion of the locus, and one person beginning in the northwestern edge and moving southeast. No special finds were found in locus 3. Taking into account the elevation of Locus 3, along with the profile finds, Locus 3 is an unsecure, decontextualized top soil deposit that is equivalent to Loci 1, 5, and 10. Locus 2 underlaid Locus 1 and overlaid Locus 4.