A sinkhole opened up in a drainage easement maintained by an HOA. The cause of the sinkhole was identified as an improperly-seated gasketed joint between two 24″ HDPE stormwater pipes. The sinkhole was large enough that a few minutes of digging with a shovel exposed the entire joint.
Chemical grout injection into the joint from the outside of the pipe to grout the annulus between the ID of the female and OD of the male end of the joint.
Single component chemical grout injection successfully sealed the entire circumference of the joint. Visual inspection via injection holes was used to confirm the complete travel of chemical grout around the entire area of the joint.