For the renovation of the wastewater containment system, a trough-shaped excavation with sheet piling, a submerged concrete base, and an HDI seal was planned. Alternatively, a microtunneling method using mechanical excavation was proposed.
Challenges such as boulders and non-load-bearing soil complicated the implementation. The solution involved drilling replacement holes, which were then backfilled with liquid soil—thus creating a stable foundation for further construction.
