Situated about 300km offshore south of Hong Kong, the first Liwan exploration well was drilled in early 2006. Extensive seismic surveys were then undertaken over more than 3,000km2 that led to definition of several more prospects.
Following concept screening studies in searching for a robust development solution, it was determined that subsea wells located at about 1500m water depth would be tied back to a fixed platform on the continental shelf at about 200m water depth. This also provided flexibility for further development of nearby prospects. The platform provides basic processing and compressing for delivery via pipeline to the onshore processing plant.
From the onset of the pipeline project during its conceptual design stages in 2009, RPS has been involved in the planning, lead, execution and management of geosurvey investigative teams to acquire the required data in support of their Front End Engineering and Design (FEED) for both pipeline routing and subsea facilities.
Due to the size of the project and shareholdings, the marine geosurvey was divided into three segments; nearshore, shallow water and deepwater. RPS took the lead in planning, tender and management of these geosurveys for all three segments, meeting the challenges with survey vessel audits, equipment selection and general survey planning. Due to logistics and monsoonal weather restrictions, these surveys were conducted over a period of two financial years.
One of the highlights of these surveys was the use of the technologically sophisticated Autonomous Underwater Vehicle (AUV) for the mapping and survey of deepwater subsea facilities and associated pipeline routes, especially for routing design up a steep submarine canyon towards the proposed platform location on the continental shelf. This unmanned untethered vehicle, equipped with a suite of high resolution survey sensors acquiring swath bathymetry, seafloor imagery and shallow sub-bottom profile data, performed a pre-programmed routine until its battery run out where it will surface and dock with the surface vessel. The use of an AUV was a first in China, and also coupled with this first deepwater project in China, made the Liwan deepwater project a ‘high profile’ project for the country.
In addition to looking after Husky’s Geosurvey concerns that included review of all reporting and QA/QC of all survey related activities, RPS also provided expertise and advice in the trial and subsequent installation of the LBL underwater positioning arrays along the proposed pipeline route. This also led to the provision of survey engineers for survey quality assurance during their initial deepwater pipeline installation activities in 2012, which is expected to double in 2013. RPS is now poised to provide continual quality assurance support services for Husky’s continual pipelines and subsea facilities installation programs for 2013.
With a reputation for providing reliable and efficient support, RPS was recently engaged to support and assist yet another project team within Husky Oil China in planning a Geosurvey program for a downstream export pipeline from the Liwan Onshore Plant to Hong Kong.