Geo-Environmental Services
OK so not exactly Peru, but a very steep, terraced site in the Chilterns.
The extremely tight access didn’t prevent our site team from getting in and completing a comprehensive geotechnical investigation, including soil sampling and dynamic probing to 10m depth. The work was completed on time and on budget, with dynamic probing data issued to the client on a ‘same day’ basis to assist with pile design.
We have recently completed an incident response investigation of a domestic heating oil installation located at the centre of a residential accommodation block complex in southern England. The site overlies chalk and is located just 100m from a public drinking water supply borehole.
Following complaints of possible oil contamination issues from the residents we took samples of the underlying soils and audited the fuel installation. With only footpaths leading to the tank installation we used our Terrier drilling system – which can fit through a standard doorway – to install boreholes either side of the oil tank and take soil samples for rapid analysis in our UKAS laboratory. Fortunately no significant soil contamination had occurred and our recommended improvements to the installation are now underway. The entire project, from initial enquiry instruction to report issue, was completed in under 4 days.
Project value ~£2k. Client value £££
Sometimes it really just isn’t that bad to be on site! Could this be the start of a long, hot summer? We hope so.
Subadra have recently completed what has been, perhaps, our trickiest ever underground tank removal. The tanks at the former filling station were located close to the site boundary. Removing them might destabilise a Victorian house on the adjacent property. To prevent this a contiguous bored pile wall was installed together with a supporting steel truss. Our job was to safely ease the tanks out from under the truss without compromising its structural integrity, before cutting them up and disposing of them as scrap metal. All this on a crowded site with construction of the new structures well underway.
Contract Value £20-£50k
Subadra has just completed environmental investigations at a portfolio of 25 retail petrol filling station sites on behalf of a major oil company. The project was brought to completion on time and on budget, using a combination of our own drilling equipment, our in-house UKAS accredited laboratory and reported by our highly experienced consultants.
Contract Value: £100-200k
…of Central London in this case. Subadra has completed a week of pile probing at a cramped development site in Central London. Despite obstacles such as leaking water mains, piling rigs and deep excavations we successfully probed sixty locations to verify the presence of below ground obstacles that might impede the construction of the engineers’ piled foundation solution and contiguous boundary piles. The contractor used this information to target additional ground clearance the key areas of concern.
Contract value: <£5k
Environmental planning conditions are commonplace in brownfield development and much of our work is involved in the negotiation of discharge of such conditions. We have developed excellent relationships with Planning Authorities and Environment Agency/Scottish Environment Protection Agency over the years and enjoy a good success rate in planning condition discharge.
Earlier in the year Subadra were commissioned to assist in a significant phased retail development on the south coast of England. The site is within Zone I of a Source Protection Zone, overlies Chalk and is 40m from surface water. In other words it is in an extremely environmentally sensitive location. Initial investigation works had identified diesel and waste oil in shallow groundwater under the site.
This is where owning our own drill rigs and our own laboratory comes into play! We were able to delineate and characterise the contamination, and install sentinel wells within a month and without delaying the build programme. As a result of our detailed assessment, we’ve negotiated a long-term remedial solution for the site, installed the required groundworks and construction works have commenced.
Subadra have been retained by a major food wholesaler/distributor to carry out a comprehensive audit/investigation of the fuel storage and supply infrastructure at a multi-site portfolio across the UK. Key to winning the contract was our ability to complete the project within a tight timescale. This is only possible because of our unique approach whereby every aspect of the project will be carried out using in house resources, from borehole drilling through to laboratory analysis; and, of course, our competitive rates!
Sometimes you need a detailed ground investigation with large numbers of boreholes, utilising a variety of different investigation tools (drill rigs, plate bearing tests, pile probing etc), with data collected and assimilated over a period of days or even weeks, that delivers a detailed description of site geology and provides a well defined contaminant delineation.We can do this for you.
However, sometimes you need a basic no frills contamination survey that is both cost effective and done on a very fast turnaround.Here at Subadra we own and operate our own survey team, drill rigs, chemical analysis laboratory in addition to our team of highly skilled geotechnical and environmental consultants that are responsible for collating, assessing and the reporting the data we produce. This means we can carry out high quality, cost effective Phase One and Two contamination surveys within days.This service proves invaluable for may of out clients who are always on the lookout to purchase new sites to add to their portfolio and don’t want to lose out on a lucrative deal or, perhaps worse, get caught out by discovering contamination issues after the site has been purchased.
SPOSH? POSH? (insert baffling acronym of your choice here). Sometimes our industry really makes a meal of what should be a simple process. How do you determine if a site is contaminated or not? We think the answer is simple: do a decent site investigation!
We have recently been working at site that proved to be a classic example of a ‘cheap’ site investigation saving nothing. The original investigation was carried out by others four years ago. After many other consultants were hired but failed to provide any clear answers (or any answers at all) we were commissioned to break the impasse.
We constructed 180 boreholes on a 5m grid using one of our dynamic sampling rigs. Boreholes and sampling locations were surveyed using GPS allowing us to develop a 3D contaminant profile of the site. Finally
sufficient information is now available to allow our client to make sensible decisions regarding future use and/or remedial strategy for the site. All this without resorting to any obscure and baffling acronyms.