EMS Geotech were commissioned by a local development company in September 2019 to undertake a Phase 2 investigation on an area of land on the Rotherwas Industrial Estate, Hereford. It was proposed to develop a commercial / light industrial unit on the land.
The Phase 2 investigation was undertaken to identify any contamination risks to the project. This included a site walkover undertaken by one of EMS’s Geo-Environmental Engineers; compilation of historical land use, geological, hydrogeological, hydrological, environmental and recorded contamination events of the site and surrounding area.
The researched history of the Rotherwas Industrial estate revealed that from 1916, the area was owned by the Ministry of Munitions and Hereford Royal Ordnance Factory (Hereford ROF) was constructed. The factory was a facility for filling artillery shells and used chemicals such as picric acid, trinitrophenol, trinitrotoluene (TNT), ammonium and dichlorethyl sulphide (mustard gas). The factory was open and in operation during both world wars and eventually closed in 1967. From 1975 the entire area began to be redeveloped and named the Rotherwas Industrial Estate.
A conceptual site model was produced using all available information for the site.
Although it was a considerable length of time since Hereford ROF closed, it was deemed necessary to undertake an intrusive Phase 2 environmental investigation of the site to further understand any potential contamination.
The Phase 2 intrusive investigation was undertaken in October and consisted of seven machine dug trial pits to expose the soil and facilitate taking geotechnical and environmental samples. The location of the trail pits were predetermined before site works began, to gain a representative spread across the site.
Each trail pit was logged by one of EMS’s Geo-Environmental Engineers and samples were taken and subsequently sent to various laboratories for testing. The outcome of these tests showed slightly elevated levels of Ammonium across the site.
The decision was made to undertake further intrusive works and three hand dug pits were excavated in December 2019. The holes were logged, and geotechnical samples obtained, which were send to a laboratory to be analysed for explosives.
The results of the analysis showed that no elevated levels of explosives were found within the samples. A revised conceptual site model was produced using the compiled information from the Phase 2 investigation and the site was deemed to be very low risk of any contamination and further investigation was not deemed necessary.