IDOM Merebrook, a leading environmental engineering consultancy is supporting the remediation of a challenging site for redevelopment in Tipner, Portsmouth. The site forms part of a former tar works, chemical works, oil storage depot and scrapyard.
The development is on the edge of Tipner Lake – a Site of Special Scientific Interest RAMSAR site and a wetland conservation zone. Tipner Lake is connected to Portsmouth Harbour and provides an important habitat for wintering birds.
The contaminated land team has worked in partnership with PMC Construction and remediation specialists Soilfix to implement the approved remediation strategy that will allow the contaminated site to be reused for a residential development and ensure the safety of future residents and the surrounding environment.
The site presents a variety of challenges including a wide range of contaminants such as metals, hydrocarbons, VOCs, asbestos, cyanide, tars and phenolic compounds. This is in addition to the site being built on land reclaimed from Tipner Lake using a series of World War II barges, creating interesting challenges regarding water management and obstruction removal.
Throughout the project contamination hotspots are being removed and bio remediated before being stabilized, and used as backfill to the remedial excavations. The stabilized soils will form a plug to prevent impact to the underlying Chalk aquifer and an impermeable barrier has been installed to prevent any contamination from reaching Tipner Lake.
Future water flowing through the site will be allowed to leave through permeable reactive carbon gates which will remove contaminants. Once the remediation phase is completed the site will be capped to seal off any residual contamination and levels raised to protect from flooding.
On site the team of consultants are carrying out daily environmental monitoring of noise, dust and odour levels to ensure the site works are carried out safely and without negative impact for workers, surrounding residents and wildlife.
Nigel Huish, Managing Director, IDOM Merebrook commented:
“Britain has a housing crisis and sites such as Tipner are an important part of addressing the shortfall, it is imperative that land does not go to waste and can be successfully remediated.
It’s normal for former industrial sites to be contaminated as a result of their historic uses. However, this can all have a significant impact the success of regeneration projects, so it’s it’s crucial to consult an expert team and undertake robust, practical and cost-effective land remediation works.
While this has been a challenging site for our consultants – from treating grossly contaminated soils, providing clean soils in areas of soft landscaping, the management of Japanese knotweed, tank, scrap metal and concrete removal, we are now in a position where the land will be fit for purpose and a new space for community living and working can be created.”