Don’t be put off by groundwater contamination on a small site. While it can be a difficult and time-consuming problem to deal with, it can be managed.
Scope the Problem With Targeted Investigation
Most site investigations end up being far too expensive for small sites. A specialist can very quickly define the boundaries of ground contamination by undertaking targeted borehole sampling around the likely point of entry of contamination to site (e.g. around the base of fuel tanks, near to underground drainage runs etc.). In most cases a handful of well placed boreholes will define the extent of ground contamination known as a ‘plume’ without the need for an expensive full-site investigation.
Choose a Low-Footprint Technique
Situ treatments such as in-situ chemical treatment can be effective at small sites, and can provide a cost effective solution without the requirement for excavation of contaminated soils. Other suitable solutions include monitored natural attenuation (MNA) and the use of permeable reactive barriers (PRBs). These can be installed within a narrow trench.
Work Within Access Limits
Access restrictions and live operations can present problems on small sites, so be sure to discuss these with your contractor in advance. He may be able to use a lightweight drilling rig or hand-augered boreholes instead.
Plan Monitoring Proportionately
When remediation is underway it is also important to remember that monitoring groundwater remediation at a small site will often involve quarterly sampling of groundwater from two or three boreholes against trigger values for contaminants. Also remember to keep records up to date from the outset as these will be required to provide evidence of what has happened at the site in the future.
Communicate Simply With the Regulator
The Environment Agency expects reporting to be of a proportionate nature and for you to send a simple factual update with details of work undertaken, results obtained to date and planned work going forward. Refer to the contaminated land guidance on the Environment Agency’s website for expected format. A useful reference for Groundwater Remediation is soilfix.co.uk/services/groundwater-remediation/.
Getting the scope right from the off is crucial to achieve your goals in the shortest timeframe with least cost.
