Page 17 - Industrial Plants

Figure 3 - Preparation
of Launching Platform
and drilling Pad

• Definition of the optimal distribution of roller 91,000 cubic metres of earthworks overall and 16,000
supports and the vertical and lateral loads cubic metres of imported material from adjacent areas.
required for designing their foundations, under By Fall 2022, the preparation of foundations and
pullback and hydrotest conditions; installation of bridges on Falls Lake Rd. and Falls Lake
• Identification of the optimum positioning of the Creek was completed, and further grading of the drag
station for the tie-in of two strings, guaranteeing section was completed in late 2022.
minimal longitudinal stress and bending moment; Afterward, stringing and welding of the first two strings
• Calculation of any possible longitudinal or vertical (each 378 metres) was completed by the end of
uplift displacement, possibly requiring additional January, 2023, while fabrication of the main string
restraints or anchors. (1,100 metres) was completed in March, 2023.
A preliminary hydrotest of the strings had been planned
for April, 2023 – one month before the planned
pullback – allowing the completion of support
Pipeline Strings and Rollers Way installation and equipment mobilization.
Preparation

Given the project timeline, Bonatti/Kiewit developed a
suitable schedule to accommodate the required Pullback Execution
deadlines, using different teams working in parallel. The final pullback preparation activities started in Figure 4 - Secondary
September, 2023, with the mobilization on-site of the strings pre-fabrication
Regarding the proper works of the HDD execution, the
pilot hole was executed from August to October, 2022
from the North pad to the South pad, confirming the
findings of the exploration borehole executed in 2021
and the low risk of bore collapse along the majority of
the HDD alignment. Subsequently, the reaming phase
started in late October, 2022 and progressed through
the winter.
In parallel, works for the preparation of the prefabricated
string and its associated working ROW were carried
out: initially grading and blasting of the section upslope
near Falls Lake Road starting June, 2022. Later, the
section between Falls Lake Road and the Drilling Pad
required significant earthworks to build a 10 metres
high launching pad for the overbreak section. The
preparation of the pullback ROW required about

IndustrIal Plants - May 2024
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