A new field for us, if accessed from a well trodden path.

Terrenus is now part of the push for sustainable energy having been commissioned to analyse the watercourses associated with two proposed hydro power stations. Working alongside CASA Planning and Environment this will utilise our background in fluvial flood modelling for both high and low river flows and broadens the scope of our capabilities in a very useful direction.

We’ll keep you posted on developments.

Some of you may remember Alastair Spearing, who worked for us for a while before leaving to join the army in 2008. He enlisted and was trained at Sandhurst, before joining 28 Engineer Regiment, where he was attached to the Counter IED Task Force in Afghanistan.

On October 6th Last year, while on a patrol in the Helmand Province, Alastair was hit by a roadside bomb, losing both legs and almost his life but for the quick action of a young soldier who administered first aid on site. Alastair was recovered to the UK and Selly Oak hospital in Birmingham, where he has gone through numerous surgical procedures and intensive physiotherapy. Amazingly, he was released home for Christmas and New Year but has returned to the Headley Centre for a period of rehabilitation and recovery.

Alastair’s spirit has amazed  us at Terrenus. When we initially heard about his injuries it took a few days to track him down and, when I first contacted him in November, he said that “the first two weeks were hard”. This attitude has inspired us to dedicate our annual fund-raising efforts to Help for Heroes, without whom the support for injured soldiers returning from duty would be much diminished.

We have planned a number of events to raise funds and set an ambitious target of £5,000. Our initial fund-raising event takes place on 22nd January, when Willie and I will attempt to complete 200 miles each in one day on static bikes in the Dollan Aqua Centre in East Kilbride. This will be followed by a number of other events, which will be timetabled shortly, culminating in a major event taking in the four countries of the United Kingdom in the late summer or early autumn of 2012. We know what we want to do but the details haven’t been finalised; we hope to notify you of our intentions shortly.

In the meantime you can make a donation to Help for Heroes through our By My Charity page. You can also follow our progress on Twitter and Facebook if you are so inclined.

Many thanks, in anticipation, for your support.

Well, not really. I enjoy writing the blog posts and I hope that you all get something out of them. The problem is trying to find subject matter and present it in such a way that it is useful to you and, hopefully, easy to follow. My blues relate to the subject matter, as I often notice people’s eyes glaze over when I tell them what I do. This particular blog post is an unashamed attempt to put the load back onto you, the reader, so that I don’t always feel like Seasick Steve when I try to think up a subject to write about. Besides, I dont have a porch or a rocking chair and I can’t play the guitar.

Anyway, back to the subject in hand. What would you like to see in our blog posts? You may have a specific question relating to a site you or your client is looking at or you may have a more general query about issues you come across but you’ve never asked anyone to clarify matters for you. If this blog post strikes a light feel free to drop me a line and I’ll do what I can to answer it, either in a blog or by private correspondence if you’d prefer. Depending on the subject matter your answer might come from me, Steven or William but you can be assured if it’s a question we can answer we will.

So, from contaminated land to soil gas, ground engineering to shallow mining, flood risk to SuDS, and all the way to waste issues and invasive plants, please feel free to give us a try. Heck, we may even be able to answer questions on cycling, running, photography, bringing up the kids or Playstations, but we do draw a line at relationships. That’s Seasick Steve’s area of expertise.

We have just completed the investigation of a site in east central Scotland that forms the garden of an old Manse, built at the beginning of the 19th Century.  A smallholding of 7 acres was given to the Minister with the Manse and garden and, apparently, on working the smallholding the minister came across some coal and decided to work it. He was taken to court by a local mining company but won the case and subsequently sold the rights to mine the coal to the mining company. Apparently he took twice as much in royalty from the mining and sale of the coal as he earned from his stipend!

Anyway, the story gave cause for concern because it suggested that, if he came across the coal when working the land, it must be very shallow, so a trip to examine the mine plans was required. Unusually we came across plans dating back as far as 1752, which show a number of mine shafts in the area, indicating that coal has been extensively worked for quite some time. Later plans also told us what coals had been worked from the closest shafts to the site and at what depth. From this and the geological records we could estimate that the depth of the shallowest worked seam was in excess of 60 metres and we were able to advise that the mineral stability of the site was satisfactory without resorting to rotary drilling.

The other thing that this helped us to establish was that the minister didn’t just come across the coal, he must have gone looking for it knowing the history of mining in the area. A canny man or a charlatan? I’ll leave that for you to decide.

Thought it would be worthwhile giving a brief review of the projects we are working on at the moment just to give an idea of the scope of services that we offer.

William is working on a hydrological assessment as a contribution to an Environmental Impact Assessment for a hydro-electricity generation scheme in Angus, as well as a few flood risk assessments across the country. This work includes a flood risk modelling exercise for Dumfries and Galloway Council, which is intended to assist the Council in devising a flood mitigation scheme for those parts of Castle Douglas that are prone to flooding.

Steven is managing site investigations for a number of commercial and housing sites, including a project in Glasgow Airport. The interesting thing about this last project is that the soft alluvial soils at surface overlie a buried glacial landscape of rolling hills (Drumlins) formed of Glacial Till. Mapping the buried surface of Glacial Till is essential for foundation design. He also recently completed a remediation validation Scheme for East Dunbartonshire Council.

Fraser is working on a number of investigations for both geotechnical and contaminated land assessment for private house-builders and housing associations, the largest of which is on a former dairy site in south-west Scotland. He is also beginning the investigation of a site with a potential shallow mining problem in West Lothian. It is understood that mining commenced in the early 19th Century so mining records may be sparse but we are hopeful of turning something up.

Fraser Contributed to the Block Architects podcast yesterday. Discussions centred around marketing in the construction industry, social media, contaminated land, invasive plants and other issues. Entertaining and informative. You can listen to the podcast by following this link.

Post match analysis was mixed following the weekend with the Pedal for Scotland ride-out suffering major injury worries and the chief striker Fraser Duff being unable to take part. Those that did ride now carry the scars of the wind, the rain, the cold and the road surface conditions. The turn at Douglas did however bring the relief of a tail wind a strong finish over the Lang Wang down to Murryfield which brought victory and the added achievement of a bonus pint (I mean point).

Further match analysis is available.

William was using the cycle to raise money for World Horse Welfare who are engaged in animal welfare both here and in Africa where the lives of draft animals are improved as is the local community through sustainable development. For those who would like to donate please let me know.

Well William ran the Glasgow Half Marathon at the weekend, completing it in a very poor time, falling into the arms of his loving family and being helped to his car nearby. This was by a long way the toughest run for a long time for William who cites everything from dehydration to the wrong type of training in order to salve his rather pathetic form.  This may not look good for the Pedal for Scotland 100 mile cycle that he and Fraser are committed to this weekend coming.

You may remember that William was raising money for World Horse Welfare and, given that this could be a ‘In Memorandum’ moment with next weekend proving just that wee bit too much, if you would like to donate please contact us directly at Terrenus (the just giving site is now closed).

Many thanks.

It is common practice in site investigations these days to monitor for soil gases. Principally these constitute methane and carbon dioxide, although other gases and vapours, such as hydrogen sulphide and solvent vapour, can be present depending on the specific site conditions.

Methane and carbon dioxide are both produced by the degradation of organic materials in made-up ground or in natural organic soils, such as peat and some types of river or marine deposits. Methane is generated, together with some carbon dioxide, when the degradation takes place in an oxygen-deficient atmosphere. In general, as the oxygen content at source increases the methane content diminishes and the carbon dioxide content increases.

Methane, carbon dioxide and other gases can also be derived from coal measures and other deep geological sources. Carbon dioxide can also be produced by some chemical reactions in the ground, particularly where carbonate rich deposits, such as lime, are present in made-up ground.

Methane is generally considered the more hazardous of the two main gases, being potentially asphyxiant but, more importantly, explosive. The gas is explosive in air at concentrations of between 5 and 15% by volume, with 5% being recognised as the lower explosive limit (LEL). The explosive limits are altered dependent on the ratio of carbon dioxide and oxygen in the atmosphere. Problems arise when there is sufficient flow from the ground to create explosive atmospheres either by gas build-up in confined spaces or by dilution from high flows and concentrations.

Thankfully, explosions due to methane from the ground are rare, with the two best known incidences being the destruction of a bungalow due to the migration of landfill gas at Loscoe, Derbyshire, in 1986. Prior to that the Abbeystead explosion of 1984, caused by an ingress of mine-gas to a water pumping station, killed 16 people who were visiting the site as part of a PR exercise.

Carbon dioxide is potentially asphyxiant and is also toxic at high concentrations. Fatalities from naturally derived carbon dioxide are extremely rare and are normally associated with volcanic events; they are, therefore, more or less non-existent in the UK. However, the gas can cause various unpleasant symptoms at low concentrations and it is implicated in sick-building syndrome. In view of these hazards, exposure to carbon dioxide is controlled by health and safety regulations in the form of short-term and long-term occupational exposure levels (1.5 and 0.5% by volume respectively).

Other hazards arise from the possible presence of other gases and organic vapours, including flammability, toxicity and odour.

Soil gas monitoring is now carried out during site investigation fieldworks to enable a full assessment of the risk from gases that might be present on a site; the presence of such gases being initially assessed from a review of the geology, history and setting of the site. This includes consideration of potential off-site sources due to the risk of migration of gas through the ground.

The extent of monitoring and the risk assessment methodology is guided by recommendations made by the Construction Industry Research and Information Association (CIRIA) and the National House Building Council (NHBC). Local Authorities will normally require monitoring in accordance with these recommendations to satisfy Planning and Building Warrant applications.

Such monitoring includes gas concentrations and flow rates, as well as groundwater levels, atmospheric pressure and atmospheric pressure trend (rising or falling). Gas sampling and analysis can be required in some cases to confirm the make up of the gas from the ground to both assist in identifying a source and to confirm that no other hazardous compounds are present.

Where soil gases are detected at hazardous concentrations and flows, mitigation measures are designed in accordance with published CIRIA or Building Research Establishment (BRE) guidance, supported by a British Standard Code of Practice (BS8485-2007). Measures can include underfloor gas barriers and/or ventilation systems, passive and active (forced) ventilations systems, and in-ground barriers and ventilation trenches to mitigate the risk of lateral gas migration (either to or from a site). The requirement for and design of such systems is entirely dependent on the individual site conditions and can only be adequately completed following the gas monitoring exercise.

A final point to ponder; it would not be the first time that we have been called in to carry out gas monitoring when an initial exercise has not been completed to an adequate standard. Cost, clearly, is an issue in these cases but often of more importance is time. Gas monitoring normally takes in the order of 2 months and, depending on site circumstances, can take up to two years to comply with the published guidance. The loss of such huge lumps of time can have a major impact on development plans. It is always best to ensure the monitoring is implemented in accordance with the relevant standards from the beginning.

Well, the 1oo mile ride is now only two short weeks away and, if the truth be told, neither William nor myself have managed to get the training miles in this year like we did for last year’s ride. My promise to myself was that I would try to shave something off the 6hr35 minute ride time from last September, at least by cutting out one of the stops. I’m not sure if this will be achievable, but you have to try, don’t you?

For his sins William is running the Glasgow half-marathon next weekend; only a week before the Pedal for Scotland ride. An example of William’s Scottish roots and Calvanist upbringing, surely? Obviously a man who believes the true path to Heaven is through self-punishment in life! Ah well, he will have a full week to recover before he dons the lycra (sorry if that vision has put you off your tea) for the ride through to Edinburgh; hopefully he will have recovered by then.

Here’s a picture of me from last years ride. William’s just over my shoulder. I don’t expect you’ll see me looking quite so chipper this year and I suspect William will be the one in front.  Wish us luck.

PS: If you want to sponsor our charity this year, World Horse Welfare, which was nominated by William’s wife Jennifer, please follow the link to Jennifer’s JustGiving page: http://www.justgiving.com/Jennifer-Hume