Skip to main content

Improving site investigation - How to save time and money

Improving Site Investigation (SI)

Site investigation is so often considered by those procuring it as‘ a tick box exercise’ and therefore is not seen as a risk management tool to achieve a successful project outcome.  Expenditure on site investigation should be considered alongside the Client’s appetite to take on risk.  

Clients for development projects often see programme as a priority.  Delays at the construction stage can be significant.  Even worse is not gathering the right information at the right stage to ensure a development site is purchased at the right price.

Ground risk also is a significant factor in transportation infrastructure projects with ground conditions causing both significant cost increases and delays in completion. As recently as 2015 Amadi Alolote - University of Salford in his paper on ‘The Anatomy of Geotechnical Risk Factors in Transportation Infrastructure Projects’ noted that out of seven major highways projects that DETR reviewed in 2014 five of them were delayed by between 1 and 5 years and cost overruns of up to £516 million in total occurred for these seven major schemes.  Whilst a number of reasons were cited for these problems it was clear that the issue of sufficient investment in adequate investigations of ground conditions still prevails.

Fiscal Incentives - Land Remediation Relief
Land Remediation Relief (LRR) is the government incentive to help bring land blighted by previous industrial use back into beneficial use. It is a relief from corporation tax only. It provides a deduction of 100%, plus an additional deduction of 50%, for qualifying expenditure incurred by companies in cleaning up land acquired from a third party in a contaminated state.  The definition of land in a contaminated state for corporation tax relief purposes is not the same as Contaminated Land under the Part 2A of the Environmental Protection Act 1990. It is interesting to note the key part site investigation plays in the LRR as it is these reports that help to determine whether the land meets HMRC’s definitions and exclusions for the application of LRR.  This is where sloppy descriptions of made ground may not provide sufficient evidence of industrial activity as defined by HMRC.

To encourage better descriptions of made ground within the industry the AGS have published Guidance on the Description of Anthropogenic Material – A Practitioners’Guide.

Research and Development (R&D) Tax Relief
R&D reliefs support companies that work on innovative projects in science and technology.  The rules are different for SMEs defined as having less than 500 staff and a turnover of under €100m or a balance sheet total under €86m (possibly dependent on linked companies/partnerships) and large companies. 

SME R&D relief allows companies to:

  • Deduct an extra 130% of their qualifying costs from their yearly profit, as well as the normal 100% deduction, making  a total 230% deduction
  • Claim a tax credit if the company is loss making, worth up to 14.5% of the surrenderable loss.

The relief for large Companies is termed Research and Development Expenditure Credit.  Further details published on can be found here.

Currently it is acknowledged that construction is underclaiming, often due to a lack of awareness of what might be included.  

Planning for waste

In 2016, around 3/5 of the waste generated in the UK arose from construction demolition and excavation.  A significant proportion of waste soils end up going to landfill and 55% of the tonnage received by landfill is comprised of soils. (source DEFRA UK Statistics on waste 2020).
Sending soils to landfill can add considerably to the overall cost of a development. Not only is there the cost of transporting material to landfill and the gate fee but the additional charge of the landfill tax.  

So, what does site investigation have to do with planning for waste?  Primarily, considering waste early on in a development projects cycle will allow greater opportunity to design waste out or to look for other uses for soil arisings. This is where the scope of the site investigation needs to take account of the proposals for managing waste arisings.  

Common mistakes include:

  • Chemical data only being available and no information on geotechnical properties (for soil to be suitable for reuse it must not only be chemically suitable but geotechnically suitable too)
  • Chemical sampling based on the current/proposed end use of the site and not based on materials classification for either reuse elsewhere and/or to send to landfill.

Guidance on waste sampling as set out in Appendix D of the Waste Classification: Guidance on the classification and assessment of waste (1st Edition v1.1) WM3 seems rarely applied with little consideration of different soil population types.  Before April 2018 getting the investigation and classification of waste wrong may have not been considered important particularly if it was in the developer’s favour, this could now be a costly mistake.   

Changes in Legislation mean HMRC can recover landfill tax where material has been placed at unauthorised sites.  Misclassifying your waste and sending it to the wrong category of landfill could be considered an unauthorised deposit.  Where HMRC recover landfill tax for unauthorised deposits the recovery is at the standard rate of landfill tax only. 

In 2017 the EA published a report into a research project entitled “Waste crime interventions and evaluation project” and drew the following conclusion about the scale of this problem….. “Our work to quantify the scale of this type of waste crime identified 630kt of potentially misdescribed waste and led to 63 site or individuals being referred to HMRC for tax investigations.” Misclassification is just one of the issues CIRIA is hoping to address in their proposed project for “Sustainable management of waste soils and aggregates”.

If you want to be involved or find out more please contact Joanne Kwan at CIRIA.

Common failures

An effective site investigation pertinent to the proposed project is key to reducing ground risk; in 2004 according to an article in the Structural Engineer unforeseen ground conditions was causing a third to a half of all programme and cost overruns in development projects. Whilst these webpages are primarily directed at innovation it is also an opportunity to increase the uptake of good practice to minimise cost, avoid delays and reduce programme duration. 

This section highlights where site investigation is commonly not carried out as effectively as it could be.

  • No or incomplete desk study
  • Combining investigations - Think about UXO, Archaeology, soil, land and water quality, geotechnical properties and parameters 
  • Investigation not relevant 
  • Inadequate risk of historic mining features or voids
  • Insufficient reporting of the works undertaken (at the most basic level, co-ordinates and ground elevation to a recognised co-ordinate system/datum)
  • Poor (inaccurate, incomplete or out-of-date) logging and stratigraphic descriptions