Transport NSW is planning to construct and operate a new 12 km light rail service from Circular Quay to Central, Kingsford and Randwick stations via Surry Hills and Moore Park. In preparation for this, a large amount of survey and investigation work was required to identify underground facilities (such as communications, electricity, gas, water, drainage and sewer) that would require possible relocation due to conflict with the future light rail tracks. 157 trenches were cut along the entire length of George Street and some ancillary roads. The pavements were generally 500 mm thick, consisting of asphalt over concrete pavement. Below the pavement were various soils, followed by a clay subgrade. The services were located either directly under the concrete slab or at varying levels to 2 m below. To expedite the trenching process and to avoid the possibility of open trenches at the end of a shift, it was decided to excavate each trench in a three phase process. An additional challenge was the requirement of having all work completed at night, between the hours of 11.00 pm and 4.30 am, with the road being open to traffic by 5.00 am.