We're going through the site where a Watertronics booster pump station was installed after the irrigation was switched from well/pump to domestic supply. Completed a section of the field and then activated it over the weekend for three straight nights so water could get to a very thirsty area. Ran into this lateral line break. It was caused by the original contractor having everything in a bind and then not sufficiently cutting out the valve box end for the 2-1/2" lateral line. Vehicles pass over this box which then settled onto the pipe and applied enough pressure to break the SCH 80 nipple. Did our normal 90/90 reroute to relieve the pressure and all is fine now. No part of the new box will come into contact with any of the piping. If I have future problems with box breakage in this area then I'll switch the valve boxes out to Christy concrete boxes with cast iron lids.