Hagstrom Drilling worked alongside 4DGeotechnics to conduct a geotechnical survey of the BHP Chichester Fill embankment site located south of Port Hedland.
The target site rail embankment had an average elevation of 15 metres above ground level.
In order to conduct this project safely and efficiently at such a high elevation DR009, a track mounted geotechnical drill, was mounted onto a BHP flat bed rail cart for the duration of the works.
The rail cart was equipped with all consumables and equipment, including lighting plants for night works, to be self sufficient for the duration of the rail shut.
Once loaded, the drill spread was mobilized from Port Hedland to Chichester via rail utilizing a BHPIO locomotive.
Once on site, the drill rig was maneuvered via locomotive over the length of the rail embankment to commence the scope of works.
The initial scope of work was 4 x HQ3, triple tube diamond drilling, boreholes to an average target depth of 15 metres below rail level.
Hagstrom drilling conducted 24 hour drilling operations to ensure all elements of the scope of work where accurately completed within the seven day BHP rail closure.
In Situ testing, such as Standard Penetration Testing and U63 thin wall tube samples, was conducted during the diamond drilling process to provide indicative geological representation of the rail embankment.
Hagstrom was able to maintain excellent sample recovery and test results through difficult ground conditions, namely embankment fill, comprising of fractured rock and overburden materials.
Upon borehole target depth being met, Hagstrom completed dual Vibrating Wire Piezometer (VWP) installations, including grouting, at depths indicated by the geotechnical engineers on site.
Hagstrom Drilling was able to accurately complete the initial scope of works, plus an additional borehole, within the seven day BHP rail closure.