Hull Gas Works

The former Clough Road Gas Works in Hull is situated to the north of the city centre. The site covers an area of 17 hectares within an industrial district located only 20 metres from the River Hull. Gas had been manufactured on the site since 1824 until its closure in the early 1970s. Site investigations had identified contamination to soils and groundwater by gas production by-products including tar, poly-aromatic hydrocarbons (PAHs), ammonia, spent oxide, phenol, cyanide, TPH and heavy metals.

The remedial works were undertaken by VHE over a 72 week programme of excavation, on site treatment and disposal of segregated wastes, together with groundwater treatment.

The excavation of over 110,000m³ of material was carried out of which 55,000m³ was sentenced for treatment by bioremediation (20,000m³ by VHE and 35,000m³ by subcontractors EESI). Excavations were backfilled using a combination of imported materials and site-sourced materials, with the intention of maximising recycling wherever possible. The project also required the off-site disposal of up to 40,000m³ of material contaminated with "Blue Billy"; however, due to a process of careful segregation this was reduced by 50%. Segregation work included sample screening every stockpile of excavated material for asbestos. Any asbestos containing materials were subsequently classified and treated or disposed of following a quantitative assessment.

Hydrocarbon contaminated groundwater was pumped into storage tanks prior to passing through an in-house water treatment plant which comprised sand and carbon filters. All remedial was undertaken with care to monitor and control noise, odours, vapours and dust. The remediation of this site will enable its redevelopment for commercial or industrial end-use.

The works also involved minor civils works including construction of a reinforced concrete service bridge and drainage reinstatements including kerbing, footways and over 15,000m2 of surfaced car parking space.