Which statement is true about installation systems used for trenchless main replacement?

• A. Only one system is used
• B. Static bursting is used with Pneumatic
• C. Hydraulic is not used for trenchless installations
• D. All of the listed options (Static bursting, Pneumatic, and Hydraulic) are trenchless installation systems

Answer: (D)

Trenchless main replacement relies on methods that install a new pipe without a full open trench, using different mechanisms to fracture or advance the old pipe while pulling in or pushing the new one. Static bursting uses a bursting head pulled through the existing pipe under tension, fracturing it as the new pipe is pulled into place behind the head. Pneumatic bursting employs compressed air to drive the bursting head forward, enabling rapid progression and simultaneous installation of the new pipe. Hydraulic methods use fluid pressure to move equipment and assist in bursting or pushing the new pipe into place, again with minimal surface disturbance. Because all three approaches—static bursting, pneumatic bursting, and hydraulic methods—are used in trenchless main replacement, the statement that all listed options are trenchless installation systems is true.