Cone

The section between the top of a manhole wall and chimney or the frame. The diameter of the manhole is reduced over the cone section to receive the frame. The cone section may be concentric or eccentric.

Consolidation

The gradual reduction in the volume of a soil mass resulting from an increase in compaction.

Contact Grouting

GroutingThe process of filling voids or modifying/improving ground conditions. Grouting materials may be cementitious, chemical, or composed of other mixtures. injected into the void space between the jacking pipe and the ground after the drive is completed.

Contaminated Plume

The underground trace of an environmental pollutant.

Continuous Sliplining

See Sliplining(1) General term used to describe methods of lining with continuous pipes and lining with discrete pipes. (2) Insertion of a new pipe by pulling or pushing it into the existing pipe and grouting the annular space. The pipe used may be continuous or a string of discrete pipes. This latter is also referred to as Segmental Sliplining. or Lining with Continuous PipeMethod of lining with a pipe made continuous for the length of the section to be renovated prior to insertion, and which has not been shaped to give a cross sectional diameter smaller than its final diameter after installation..