CASE STUDIES - ENVIROMENTAL

Phase One Desk study (Griston, Norfolk)

A private individual wished to develop a plot of land in Griston, Norfolk for residential end-use.  As the site was proposed to contain greater than 10 No. residential dwellings it was deemed appropriate by the LPA to impose certain conditions upon the Planning Application.  One of those conditions was to provide a ‘Phase One’ study which comprised a review of available data and a site walkover survey in order to assess risks to a range of receptors (including humans, structures or existing groundwater/surface water).  AFHA carried out the work in less than a week and found that insignificant risks were posed to receptors and allowing the condition to be removed and the development advanced.

Client:             Private Individual
Cost:               <£1k

Phase Two Environmental Health Investigation (Lowestoft, Suffolk)

A former smokehouse premises, part of which was Grade II listed, located in Lowestoft, Suffolk was proposed to be redeveloped for residential end-use.  A Phase One investigation identified the potential for Poly-Aromatic Hydrocarbons (PAHs) to be contained within the buildings structure and suggested this may be a risk to future residential end-users.  Subsequently the Local Planning Authority (LPA) required an intrusive investigation be carried out to determine the extent and quantify the concentration of PAHs in the buildings structure.  A programme of sampling surface materials and coring for deeper samples was developed alongside a chemical testing regime which was approved by the LPA.  Subsequently, laboratory test results found that surface materials were contaminated with PAHs and the core samples were not.  Therefore it was recommended that sand blasting and steam cleaning of the structures internals should be carried out to mitigate exposure of surface materials to end-users.  Visual inspection upon completion of mitigation works would comprise sufficient validation, allowing redevelopment to proceed.

Client:             Tiuta plc
Cost:               <£5k

 

Contaminated land site investigation (Stowmarket, Suffolk)

A former fuel transfer depot was purchased by AFHA’s client and earmarked for redevelopment of the same activity.  As an environmentally considerate land owner and to ensure redevelopment of the site remained unencumbered by planning conditions, the client commissioned an investigation to identify any on-going or historical contamination caused by on-site activities. 

Clean drilling techniques were utilised for each borehole and decontamination procedures followed between borehole positions.  The site was found to be contaminated with hydrocarbons in both soil and groundwater.  Intrusive investigations and subsequent environmental monitoring was carried out to enable quantification of contamination on-site.  An environmental analysis was undertaken to determine the potential for off-site migration of contaminants which was subsequently found to be unfeasible.  A small scale clean up exercise was advised and commercial activities were allowed to proceed without hindrance from regulatory authorities.

Client:             Goff Petroleum

 

Geo-environmental investigation for £3.7 million North Walsham Cottage Hospital redevelopment (North Walsham, Norfolk)

A geo-environmental investigation was commissioned by the structural engineers Thomasons on behalf of Norlife Limited, AFHA’s client, for a £3.7 million redevelopment of North Walsham Cottage Hospital, Norfolk.  Demolition of existing and construction of a new 24 bed ward was proposed with the investigation required to be carried out and reported within 2 weeks. 

An assessment of potentially contaminated soils was carried out to assess risks to potential receptors including future patients, no significant elevations were identified. Window sampling, trial pitting and dynamic cone penetration testing was utilised to provide a range of geotechnical parameters required by structural design engineers to ensure a cost efficient and suitably engineered soakaway and foundation solution was developed.  The investigation was completed on time and within budget

Client:             Norlife Limited

More information on the redevelopment project can be found here: Link

 

Thermographic surveys (Romford, Essex)

As part of a preventive maintenance program, a thermographic survey was commissioned at a sub-station site in Essex.  At the instruction of AFHA’s client, a thermographic inspection was carried out of breakers, bus-bars, bus-bar isolators and feeder isolators to identify any areas of over heating.

Client:             Freedom Group of Companies Ltd
Cost:               <£1k

 

Acoustic Surveys (Grafham, Cambridgeshire)

As part of health and safety and site handover requirements, a noise survey was commissioned at the redeveloped Ozone generation facilities at Grafham Water Treatment Works (WTW), Huntingdon.  At the instruction of AFHA’s client a survey was carried out to provide information on the maximum noise levels emitted by mechanical equipment associated with the ozone generators and machinery.

Client:             Biwater Services Ltd acting on behalf of Anglian Water Services Ltd
Cost:               <£2k

 

Ground Gas Risk Assessment (Costessey, Norwich, Norfolk)

A site was proposed to be developed for commercial end-use.  However it had previously been identified as being at risk from ground gas due to being designated as a site of former sand and gravel extraction.  Therefore the Local Planning Authority imposed a condition stating that a ‘site investigation for the methane, carbon dioxide and oxygen in the ground on the site must be undertaken’.  AFHA’s client commissioned such an investigation which subsequently carried out environmental monitoring for ground gases in accordance with CIRIA guidance.  Insignificant amounts of ground gas were identified through this process and risks to receptors were considered low.  Therefore the development was permitted to proceed.

Client:             Citygate Developments Limited

 

Flood risk assessments (Norfolk)

A Flood Risk Assessment (FRA) was commissioned by AFHA’s client and was required as part of an outline planning application for the site.  The FRA was prepared in accordance with Planning Policy Statement 25 “Development and Flood Risk” (PPS25).  It incorporated (i) an assessment of the potential to increase flood risk elsewhere, through the addition of hard surfaces and (ii) the effect of the new development on surface water run-off.

Client:             Bylaugh Hall
Cost                £<2k