Geo-Environmental Services
We were asked to carry out an environmental ground investigation at a disused transport depot. Not surprisingly this identified diesel contamination at ~2m below ground level.
There was no sign of any obvious contamination source and given the site’s previuous use as a transport depot, we thought it likely that an abandoned below ground fuel tank might be present.
We therefore went back to the site and carried out a shallow trial pitting exercise which revealed……well, you can see for yourself.
Last week we undertook window sampling and installed monitoring wells at one of the largest recycling processing depots in the UK. Have you ever wondered what happens to your recycling after it gets taken away? Well it will likely end up at a processing centre similar to this one, where the waste is separated, segregated and prepared for recycling.
It was eye opening to see the scale of the operation. Usually when we drill, our rig is one of the bigger vehicles on site, but this time our van mounted Geoprobe was dwarfed by some of the other machines on site.
Our Terrier drill rig, Tinky, recently celebrated its sixteenth birthday. In that time it has had 2 new head gaskets, 15 calibrations, 22 oil changes and services, 2 new tyres, 2 new tracks, 1 rebuilt mast frame, 1 new radiator , 1 new weight guard and a new fan. We know that good maintenance is the key to keeping any machine working and we like to think we’ve done our Terrier proud. It has certainly paid us back.
It may be sixteen years old but last week it still managed to dynamically sample 25m of weathered sandstone to 5m depth with SPT tests every metre plus completing an additional four dynamic probes to competent bedrock at 9.5m and installing four gas monitoring wells to 1.5m. All this in two days including a round trip mobilidsation of over 300 miles. Hats off to Tinky.
We are looking for dynamic sampling operatives. If you think you fit the bill then give Angus Gale a call on 01296 739400 or email your CV to Angus Gale.
The latest prosecution by the Environment Agency of a filling station operator has resulted in a record fine of £8 million. The Environment Agency’s investigation found the leak resulted from the operator’s failure to address a known issue with the fuel delivery system and an inadequate alarm system. It was compounded by “poor” emergency procedures. The leak affected local residents and local watercourses, with leaked fuel entering the Langwood Brook resulting in fish kill. County councillor Albert Atkinson, deputy leader of Lancashire County Council, said: “The fact the leak was allowed to continue for more than 24 hours undoubtedly contributed to a risk of harm to people living and working nearby, as well as emergency services attending the incident.”
We believe that this case marks a change in approach from the Environment Agency, with a focus on prosecution under health and safety legislation rather than the available environmental regulations. The resulting fine of £8 million was significantly higher than fines levied for similar incidents prosecuted for polluting controlled waters.
Further details can be found here.
A prominent pipeline client came to us with a problem. A ‘positive’ problem that is. A section of their pipeline runs underground next to a railway line. The railway’s overhead high voltage power lines were causing an amplified positive electrode potential in the ground, which in turn was leading to increased corrosion of their pipeline. In these cases, cathodic protection is the usual solution.
A typical cathodic protection system would comprise a series of shallow earthing rods installed at regular intervals along the pipeline. However, this requires access for maintenance in the future to the entire pipeline. But these pipelines run for hundreds of miles through agricultural land, some of which is only accessible during certain periods of the year. The solution was to design a single anode string capable of achieving the required negative electrode potential in a vertical design. Thus saving on space, maintenance and cost
The client’s senior cathodic protection engineer approached us to see if we could drill a 75m deep borehole and undertake the (negative) anode installation. We took the challenge and set about devising a safe method for installing a multi core anode string weighing more than 300kg! The borehole was installed through 18m of gravel into underlying mudstone. Just to complicate matters further, our environmental appraisal identified a potential risk of penetrating into a sandstone aquifer beneath the mudstone. To mitigate these risks and achieve the required potential we had to install a vent pipe to the base of the borehole, a tonne of coke, gravel and a bentonite seal at the top of the mudstone to ensure the underlying aquifer was protected.
Exactly how we did all this is our secret but needless to say it involved a large rig, and unusually for us, a lot of “negativity” ………….But happy pipeline equals happy client – now that’s positive.
It’s never good when your business premises are reduced to ash in a raging inferno. But this was just the scenario faced by one of our clients, when their car showr0om and repair workshop has burnt down overnight.
We were on hand the next day, working closely with both the fire brigade and the demolition crew. We were able to obtain the vital geotechnical data necessary to allow design for the new buildings to progress.
Here you can see our Terrier rig taking soil samples and completing in situ standard penetration tests and dynamic probes to depths of up to 15m.
Now the flames have died out, the demolition has been completed and the new structure has been designed. Our client is well on the way to be back in business.
As the rest of the world turns it attention to Hollywood and the Oscars, we’ve been focused on the only marginally less high-profile What House Awards. One of our clients, Q Developments, picked up two awards, one of which was for their development of a former filling station site in Teddington. We’re very proud to be able to say that we played our part in this project for Q Developments, having undertaken the decommissioning and removing the former petroleum installation and the treatment of hydrocarbon and asbestos-related soil contamination prior to the site’s residential redevelopment. Our congratulations to Q Developments on their award.
……is our mini dynamic sampling rig! In fact, its photographed here having its oil checked during a day’s work at a site on the south coast.
The geotechnical survey, which comprised standard penetrations tests (SPTs), dynamic probing, CBR tests and plate bearing tests, was designed to allow the design of foundations for a leading supermarket chain’s new store.
The site had a history of industrial development so, not surprisingly, it was littered with large, buried concrete obstructions from previous structures (foundations, beams and piles). We will soon be returning to complete pile probing at each of the new pile locations to enable the augers of the piling machines to keep turning thus avoiding expensive standing time.
Hopefully it will have stopped raining by then…..and no, sadly, we didn’t find the pot of gold at the end of the rainbow.
Autumn seems to have arrived with a vengeance. Grey, wet and windy seems to be the order of the day here in the UK. But not for one of our Consultants, who has been spending his time in Haifa, Israel, carrying out an independent review of Israel’s largest remediation project.
We were called in by the Israeli NGO to review a complex remediation project to clean up the historically polluted Kishon River. Silt and sediment dredged from the river is being treated to remove contaminants that have accumulated over decades as a result of effluent discharges from the heavy industries lining the river bank. The treated soil will eventually be used to create a nature reserve and public park. The remediation processes include water treatment using nitrification/denitrification and soil treatment using biopiling and winrows. Soil and water samples are analysed in a sophisticated on site laboratory, allowing progress to be accurately monitored.
We were able to apply our expertise in both remediation and laboratory operations to provide the client with a number of suggested improvements to the project. Getting a sun tan didn’t hurt either!
Ok, that claim may be stretching things a little, but our forensic analysis team have recently notched up a few notable successes. We were awarded a contract to treat petrol and diesel contamination in the soil and groundwater under a filling station. The site had a history of leaks, the most recent of which was six years ago. Since then one of our competitors had been trying (and failing) to clean the site up.
We were brought in to deal with the contamination once and for all. The first thing we did was to carry out some forensic analysis of the contamination using proprietary methods we have developed over the last 20 years. Our analysis indicated that there was an ongoing leak at the site, and was even able to pinpoint where on the site it was likely to be.
Our client commissioned precision tank and line testing which confirmed a slow leak under pump island 7 – just where we had predicted. The rate of leak – 0.29litres/hour – was actually below the precision testing threshold, meaning that the fuel lines passed the test and were certified as ‘not leaking’. However, this rate of leak would result in around 2,500litres of fuel entering the ground under the site each year – more than enough to cause serious contamination.
So the lessons learnt? Firstly, tank and line testing is very far from foolproof and fails to identify leaks that can cause serious environmental issues. Secondly, the timely use of forensic analysis can prevent significant time and money being wasted on ineffective remediation work.
For further information on our forensic analysis capabilities please contact Duncan Eastland or Kate Clark.