Geo-Environmental Ground Investigation, Barking Power Station

Purpose

Barking Reach Power Station operated as a 1,000 MW combined cycle gas turbine and has a long complex history of industrial land use including lubricating oil storage depot, rail sidings, motor works, concrete manufacturers and infilled land within a tidally impacted area.

The Site was designated as a RED potentially contaminated area, with the potential for hydrogen sulphide, hydrocarbon vapours, cyanide, chlorinated solvents and high likelihood of the presence of asbestos.

Delta-Simons was appointed to undertake a £450,000 ground investigation comprising combined geotechnical and environmental testing and sampling prior to the remediation of the Site and its subsequent redevelopment into commercial buildings.

Scope of Works

Delta-Simons coordinated a team of 30 employees and contractors, over a period of 12 weeks comprising:

▲ Providing our in-house drilling team - using dynamic sampling, hybrid rotary percussive rigs and wire-line drilling techniques (with aquifer protection measures and using a polymer flush).

▲ Skilled geo-environmental consultants supervised the drilling works, managing UXO risk and archaeological supervision throughout; and

▲ Co-ordinated borehole development, monthly groundwater sampling, continuous groundwater level monitoring, bi-weekly ground gas monitoring and vapour sampling.

The works comprised the excavation/ drilling of 110 locations, to a maximum of 43.5m bgl into chalk bedrock, and the collection and analysis of over 300 soil samples and 120 groundwater samples.  Delta-Simons provided daily progress reports, schedule lists, logs and chemical and geotechnical test results to the client.

At the outset of the investigation, inclement weather caused flooding in multiple areas and Delta-Simons engineers coordinated the pumping and draining to allow works to progress unhindered.  During the works we identified asbestos in soils and hydrogen sulphide gas hazards were effectively managed and mitigated throughout.

Throughout the investigation Delta-Simons also co-ordinated the resumption of works and expedition of programme following the unprecedented coronavirus pandemic to help meet client deadlines and navigated government guidance and risk assessment.

Outcomes / Client Benefit

Difficult ground conditions were encountered throughout the investigation causing delays and poor recovery, our in-house drilling team worked with suppliers to acquire a newly developed core catcher, improving recovery to 100%.

Delta Simons successfully delivered this large, intensive specification requiring both geo-environmental and geotechnical expertise to the client’s satisfaction over a period of time during the early COVID-19 pandemic where undertaking intrusive works became increasingly difficult.