Van Walt Environmental C O N N E C T
February 2016 Issue 1
NEW Level Logger Drilling the lost city Roman boat at Guys Hospital vanwalt CONNECT goes global
Confidence - Technology - Choice VAN WALT
Drilling for the lost city of Atlantis
The usefulness of a Penetrologger
Delivering excellent service & industry-leading environmental research equipment at fair, competitive prices for almost 35 years
Meet the Team
vanwalt CONNECT in Sudan
My eldest son holds quite a senior position with a company in London. He went to decent local schools, had reasonable A-level results and a good university degree. He knows all about IT disaster recovery, he can use a keyboard on his phone without looking at it, he knows all about Facebook and Twitter but, because he seldom needs to, he can’t string two sentences together without making grammatical or spelling errors. And so to the point: Over the last decade we have worked so very hard to keep up with the digital age. Our main channel of communication has been our website, emails and social media. But we have come of age and the focus for 2016 and beyond is to make sure we also talk to our customers in ‘hard copy’, giving detail, real background to a story and illustrated with lots of photographs and pictures. This magazine is one of the ways we intend to use to let you know about our company, the people who make it tick and of course the amazing projects you, our customers, are involved with. Of course we will continue to keep in touch with you with the now more accepted digital ways. Our website will not disappear; in fact we are aiming to increase our Resources Pages with more data and training videos but we hope that you will enjoy reading our magazine as well. I’m lucky enough to travel extensively and it has
Working with Network Rail
Latest technique for Groundwater Monitoring
Rental Workshops - Sharing expertise
Drilling in New Zealand
Soil or Sediment
Bugs, floods and farms
Window sampling in USA
Groundwater Monitoring with the YSI ProDSS
delighted me to be able to illustrate this first of a biennial publication with some pictures from different parts of the world. I sincerely hope that you will enjoy the articles. With very best wishes
Down by the riverside
Van Walt’s Logger of Choice
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Monitoring the Guys Hospital Roman Boat
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Drilling for the lost city of Atlantis!
At the end of September 2015, Vincent and I had the opportunity of travelling to Seville, in the South of Spain, to train members of staff from the Spanish Geological and Mining Institute (IGME) in the use of a Window Sampling System, Stitz Sampler and a Lost Cone Drilling Set. A young but very expert team of scientists led by Dr. Claus Kohfahl, a north German professor, was looking to monitor water contamination in the National Park of Doñana. Earlier this century the Doñana National Park was in the news following devastating tsunamis which drew attention to a new claim that researchers had found the lost city of Atlantis — buried in mud on the southern tip of Spain. Scientists said they had found proof of a 4,000-year-old civilisation that was buried by a tsunami. Doñana Park is a huge natural reserve, with marshes, shallow streams and sand dunes, where the Guadalquivir River finds the Atlantic Ocean. It has a very large biodiversity, with tens of bird species that find a shelter during their migrations. When driving around the park, we understand the importance of keeping this area as a reserve: mining activity is very important in the north of the park, upstream the river, and some heavy metals are present in the groundwater, from natural origin. To keep it under some certain limits makes life for plants and animals possible. In
addition, the surroundings also hold an important agricultural industry: side by side to the park fence, we can see large extensions of greenhouses where strawberries are intensively grown (the first ones that can be eaten in Europe every spring), with high demand of water coming from the ground, and to the east of the park, rice and cotton fields alternate their colours with the blue from the sky and the chalk white from small buildings, spotted about that area. In a region where sun seems to be closer to us, it produces a very clear light year round and all natural and artificial colours seem to agree to provide nice pictures to pro and amateur photographers. The trip from Seville to Doñana is also the way for one of the more popular pilgrimages in the South of Spain: El Rocío. About one million people follow dusty lanes every spring to worship the Rocío Virgin. I am sure that, together with the Chinese Wall, it is possible to see from the Moon the cloud of dust that pilgrims create! The team from the IGME is investigating, as part of their research into water levels, also quality and the extent of contamination, which is caused, aside from heavy metals also by Doñana’s proximity to an oil pipeline that runs between Estremadura and the port of Huelva.
Drilling for the lost city of Atlantis!
The water table problems are exacerbated by heavy abstraction for irrigation to maintain water-intensive crops such as rice and more recently the strawberries. The latter are grown in greenhouses, with an estimated area under plastic of between 4,500 and 6,000 hectares, producing over 60% of the Spanish crop. The strawberry farms threaten to cause damage to the park by depleting the surrounding groundwater as well as creating pesticide pollution and plastic waste which accumulates in local creeks surrounding this area of outstanding natural beauty. The problem for the team undertaking the research is the type of soil which is very sandy and difficult to sample. Collecting undisturbed samples for analysis was proving almost impossible, hence the supply and training on using our Window Sampling Set, Stitz Corer and a Lost Cone Drilling Set. The main purpose of using our equipment was to collect undisturbed samples to a depth of about 6 to 8 metres. What happens is that the sampler cutting shoe compacts the sand, converting it into a very hard to penetrate material. And, if that wasn’t problematic enough, every time we recovered the sampler, the borehole collapsed. In the end we did recover samples from about 4-5 m, which was the deepest yet. I was really impressed with the ritual when the sample was recovered above ground: the moment that Antonio, the expert driller, had the core sampler in his hands, Fernando and Natalia, in a perfect and silent choreography retrieved the sample from inside, labelled, sealed and stored it – no messing, no words necessary, complete and utter concentration on the task in hand, to retrieve a viable sample that they can then analyse in the lab, under Claus’ supervision. Our next challenge was installing new groundwater monitoring wells, quickly and non-destructively, using the lost cone drilling set. This set comprises steel casings in sections of 100cm, with at the base a cast iron cone. It is called “lost cone” because it is left in the ground. The casings are driven into the ground to the depth required, a 1-inch HDPE
monitoring well is lowered inside the casing which is then retrieved, leaving the perfect well in place. The shape of the cone makes it easy to penetrate the different layers of the soil. The cone did its job well, masterly driven by Antonio and we installed a nice 6m well and, due to the high recharge rate of that sandy site, after a few minutes we were able to start the peristaltic pump and test the quality of the water. While we were onsite Vincent insisted on the convenience of adding another piece of equipment to their research fleet: a Stitz Sampler. It consists of a piston-like sampler, driven by a percussion hammer to take us as deep as we need to sample and to obtain a good profile of sediment. So two weeks later we were onsite again this time with the Stitz Sampler. More complex to use than standard gouge augers, but with added suction strength (greater than gravity force) the equipment was scrutinised and improvements proposed by Fernando to help avoid collapsed material falling into the sampler. The recovery of expensive gouges and rods was one of the main concerns of the team and Antonio was adamant that he had to have two breakfasts to make the extraction work! People from Andalucía are famous because of their good mood and their superlative comparisons, and Antonio is a great and fun example of this. To save on breakfasts they opted for the hydraulic extraction unit and so, we started the generator, connected the hydraulic hoses and let it do its thing. While Antonio was driving the lever, his colleagues were watching with wide eyes at how easy it was to extract the equipment with no real manual effort. I must confess that at the end of our site visits, I was a little disappointed. I had watched some reports about the presence of Atlantis below Doñana and I had expected to listen to some fantastic stories about the findings of our customers during their groundwater research: some medals, amphorae, a bit of a large building …. something that, I am sure, they found but now they choose to keep secret! We will have to continue to watch the National Geographic channel, read fantastic stories about Atlas and Atlantis to find out more about the secrets that Claus, Antonio, Fernando and Natalia keep to themselves, under the excuse of water contamination in Doñana’s groundwater. They are
so good at keeping secrets that even a delicious meal with “pescaito frito” (fried fish) in front of a brisk Atlantic Ocean in Matalascañas was not enough to destroy their defences and make them talk….. Anyway, thanks to Claus Kohfahl, Antonio Martínez, Fernando Ruiz and Natalia Fernández for their hospitality, keeping the Atlantis secret and sharing their sampling and drilling challenges in sandy sediments.
Ramon Quiles Van Walt Ltd
The usefulness of a Penetrologger!
Sampling weak sediments presents particular challenges. Sampling devices can be easily inserted but retention is mostly a problem and so sampling tools need to include a valve of sorts to capture the material. This can be a flap, a piston (with or without check valve) or a closing mechanism at the foot of the sampler. Similar to soil samplers there are a number of options and the choice of one tool over another will be determined by the application. 1. Bed Grab Samplers: If the sample is below a depth of water, for example rivers, lakes, ponds, a “jaw” type sampler is easy to deploy even in deep water. The Van Veen Grabs are good examples and they come in a variety of sizes. They will just capture the surface few centimetres. 2. Piston Type Samplers: When undisturbed samples are necessary then piston type samplers are very useful. There are many types and generally they are capable of taking samples in a liner of 100cm: a) Stitz-Corer: A metal piston sampler which is inserted in a closed position and mechanically driven to the required depth when it is remotely opened by cable. The Stitz is suitable for most types of weak sediment; fast, reliable and good sample retention to depths of up to 10 metres. b) Multi-Sampler: Hand held piston type sampler which captures the sediment in a clear plastic liner. If the sediment is very weak then a check valve can be added for better sample retention. The Multi-Sampler can also be used below the
water. Typical depths, 4-7 metres. This is a very lightweight and easy to use sampler. c) Beeker-Sampler: Very similar to the Multi-Sampler but rather more sophisticated in that the head contains an inflatable bladder which seals off the head ensuring full retention of the sample. Because samples are so well retained and almost perfectly undisturbed the Beeker-Sampler is ideal for research which requires very precise profiling. It can be used below the water up to depths of 7 metres. The Beeker Sampler is often the tool of choice when the water/sediment interface is important as both can be represented as a profile in the sampler. A likely application would be the investigation of pollutants in the top layers of a river, lake or sea bed. 3. Flap Gouges: The best known is the so-called “Russian Corer” and it is very fast to sample peat or other weak sediments. Inserted in a closed position it is “speared” into the ground to the required depth. The sample is captured within the integrated chamber and retained by the “flap”. 4. Gouge Augers: Resembling an over-sized cheese-corer and whereas these augers are also used for heavier soils (in fact a window sampler is a type of gouge auger), they are particularly useful for semi weak sediments as they are available in different diameters and have operational lengths of 100cm. They are very effective at quickly taking undisturbed profile samples. Generally they are more useful for peat substrates but will also work well in more cohesive sediments.
There are a number of penetrometer types, dynamic and static and from Van Walt we have offered the cone penetrometers for a number of decades. Thirty years ago our customers were mostly involved in agricultural research and the cone penetrometer was the perfect tool to detect compacted layers. All those years ago, I remember that most farmers subsoiled routinely prior to cultivation. With time, the cone penetrometers showed that subsoiling could do substantial damage to the soil profile. Too shallow and it would be completely ineffective and too deep the (diesel) costs would rise and the soil profile could be damaged for years to come. The same applied to ploughing and under certain conditions this would lead to a smeared and compacted layer at a depth which could cause waterlogging due to the creation of an impermeable layer and consequent reduction in yields. Nowadays much more care is taken with precious soil profiles and the cone penetrometer was a tool which led farmers to consider a more scientific approach when deciding on subsoiling and cultivation methods. Cone Penetrometers do today what they did half a century ago; they measure resistance against depth and most were restricted to a maximum depth of 80-100cm. Whereas all units have always been research grade devices with calibration the easiest to read was the Penetrograph, a penetrometer which was able to show the results in a graphical form on plasticised paper. This totally mechanical device is available even today from new but most customers are opting for an
electronic version, the Penetrologger. This device can be pre-programmed with location names and a number of penetration recordings per site, so even inexperienced staff can be sent to make the recordings. Data is stored on the internal datalogger with GPS co-ordinates and the data download can take place in the comfort of the office. The software gives averaging functions and resistance measurements can be drilled down to 10mm so that very precise results can be achieved. One of the more interesting devices is the Penetrologger for top layers. A small handy unit and at one time it was used by the RSPB to determine whether the soil resistance was too high for the beaks of birds to break into the soil during feeding. Whereas the cone penetrometers were originally designed for agricultural purposes, with time other sectors wanted these small portable units for geotechnical investigations. For a while there was no correlation between cone penetration measurements and California Bearing Ratio (CBR) but in the last years a specially adapted device was manufactured to satisfy those customers who needed to work using the CBR. Cone penetrometers have also been a great success for research in the suitability and stability of landing strips. In fact, the German Army still use the CBR unit to assess the suitability of older runways to accept heavier modern jet aircraft. Especially compact units were provided so that they could be strapped to the users who would parachute to site.
Vincent van Walt Van Walt Ltd
Confidence - Technology - Choice VAN WALT
Accuracy Confident about
Vincent van Walt Van Walt Ltd
Meet the Team
It is often said that a business is only as good as its employees and here at Van Walt it’s no exception. Our team of extraordinary people are located across the UK, Spain and New Zealand, the individuals that keep our world turning. We invest in our team with individual training and development programmes for everyone to ensure they have the skills and knowledge to do their job brilliantly We want you to experience our passion and determination every time you touch us. We understand your commitment to your work and that’s why, at Van Walt, we understand it’s not just about delivering the right equipment, at the right price, at the right time – it’s all the little things we do that makes a difference, keeps your custom and makes you want to find out more about the people behind the scenes.
Yvonne Coonan Associate Director
Montse Ampuy Spanish Director
Sarah Ashford Administration
Tracey Daley Special Projects
Bill Dean Stock RoomController
Candi Fernandez Administration
Gary House Rental Technician
Lewis Irvine Head of R&D
Ikky Izagaren Sales
Reece Munn Rental Manager
Miguel Nuñez Sales Coordinator
Jess Oliver Marketing
Ramon Quiles Technical Sales
Tom Raggett Repairs Technician
Ricard Riera Rentals Coordinator
Lorraine Watling Accounts
Holly Theakston Administration
Amanda Skelding Rentals Coordinator
Dirk van Walt NZ Branch Manager
Vincent van Walt Managing Director
Water monitoring in Sudan
One of the highlights of my year was travelling to Sudan to work with The Ministry of Water Resources Groundwater and Wadis Directorate. Groundwater Basin department. Our purpose was to help the ministry set up a system to monitor the abstraction of water using our very own vanwalt CONNECT system. The story begins when Van Walt was approached by a hydrologist from Sudan, Nahid Abdelrasoul who was looking to develop her skills using the latest technology available for accurately and consistently monitoring groundwater levels. Nahid is a Hydrogeologist working for the ministry and was interested in learning all about the equipment used for groundwater monitoring in the UK and Europe. With this in mind Nahid travelled to the UK for an intensive week of training with the Van Walt team, where she learnt all about the theory behind monitoring water level and quality. Nahid gained hands on experience using the equipment we take for granted in the UK including water level loggers, Xylem instruments and INW’s AquiStar range of very accurate vented sensors. As a result of the training in the UK myself and Vincent were then invited to Sudan to see for ourselves the conditions in which this equipment would have to operate. We travelled extensively throughout Sudan, from Khartoum were we saw Marawe, the largest hydroelectric station in Africa (Marawe is impressive, spanning the width of the Nile and harnessing its water) to Kassala. It was here where we installed the vanwalt CONNECT telemetry system. The distances between these places are incredible, at least eight hours drive in a straight line through the baking desert, all you could see were white trees and miles and miles of sand. The purpose of the trip was to install equipment that would deliver, securely, highly sensitive data for the ministry in order for them to precisely see groundwater levels and allocate valuable resources accordingly. The installation took place in a small hut, it was extremely warm and the walls were covered with climbing lizards. Thankfully the installation went quickly as everyone was very keen to get involved and help out wherever they could. In addition to
the installation we also delivered a training session on how to operate the system, troubleshoot and interpret & manipulate the data. Our vanwalt CONNECT interface is very user friendly so training Nahid and her colleagues was pretty straightforward and went without a hitch, even with the language barrier. We went over how to download the data, how to produce interactive reports covering water levels and temperature, how to zoom in and out of data periods to compare different data sets and set alarms at predetermined levels to warn the appropriate authorities if levels became critical. The following day we travelled to a local village where we installed a water level logger for brackish conditions in a drinking water well, which was to make sure the villagers had an adequate and safe water supply. This was probably the most interesting well I have ever come across as there were several sticks, stones and even toys down the well from children playing games. People travelled from all over to collect water from this well; they would fill an assortment of containers, anything they had to hand, with water. After queuing for their turn to extract water they would carry it on their heads, on donkeys or encourage the children to collect and carry this precious resource home. It really makes you appreciate what you have. It wasn’t all work; Vincent and I visited the oldest pyramids in Sudan, dating back to 4000 BC and experienced traditional Sudanese cuisine and the Sudanese markets. Vincent & I are planning on returning to Sudan in early 2016 to see how everything is going, we plan to expand our vanwalt CONNECT systems and provide additional training. In Sudan I met so many interesting people; everyone was amazingly kind and generous and I will always have fond memories of sitting by the Nile, drinking tea and watching the sun set.
Lewis Irvine Van Walt Ltd
All aboard the vanwalt CONNECT Express
Protect what ’ s impor tant to you Wi th vanwal t CONNECT
Train delays can be caused by a variety of reasons, from livestock and leaves on the tracks, to flooding. That means the organisations that manage the rail networks have to contend with all the possible factors that could create a disruption to the smooth flow of rail traffic. More often than not it is external circumstances like extreme weather, landslides, blocked drains, overflowing rivers, pollutant spills, overgrown or flooded waterways that cause delays to the rail timetable. Like every other business that offers a service or product to the general public the rail network has a duty of care to deliver theirs safely, securely and to agreed service levels. That’s why an on-going programme of investment and research into better ways of managing potential risks to the assets and infrastructure is in place and why Van Walt was invited to suggest a solution to monitoring a potential flood risk situation. On HS1 infrastructure there was a risk of assets being flooded due to internal and external factors. Richard Dance, Systems Engineer, Network Rail (High Speed) Ltd contacted us in the last quarter of 2014 to discuss the deployment of a couple of systems to measure water level and to report by means of alarms when levels were getting to a critical point. The introduction of an early warning alarm would give the business time to take remedial action before any serious damage or delay occurred. Two vanwalt CONNECT telemetry systems were installed and have been running continuously now for well over a year. At the Stratford International Station end, the problem was of a different nature. An early warning system was needed to report both water level and the presence of hydrocarbons on a small lake not far from the station. Here also we installed a vanwalt CONNECT system but this time added a hydrocarbon sensor. As soon as hydrocarbons are detected an alarm is raised and emailed to the duty officer. Network Rail (High Speed) Ltd as the manager of HS1 infrastructure takes delays very seriously. Their well-trained staff identify the problem and look at solutions and we are delighted that we have been a small part of that process. One of the “hidden” extra benefits of a telemetrised system is that it throws up information which had
hitherto been unknown such as, for example, the extent of tidal influences relatively deep inland. By having data points every 15 minutes with an hourly upload, not only gives a very thorough picture of what is going on but also gives ample warning time. No-one likes to be woken up at unsociable hours, and having a system which can be interrogated remotely and that a graphic presentation is given of the events in the last few hours or days of course gives reassurance but more importantly it enables the person on duty to make sensible decisions ahead of donning foul weather and safety gear to go to site. And so on to cost: Technology and digital advances have made this type of system available at a cost which is now, by far, overshadowed by the benefits. Installation is simple, the sensors are accurate, resilient and reliable. These systems can now be configured to measure many different parameters in addition to level, temperature and hydro- carbons, so are suitable for multiple applications and requirements. Confidence, Technology and Choice are now perhaps clichéd buzzwords but at Van Walt we strive to put a good dose of each in the melting pot and vanwalt CONNECT is a good example of what can be achieved to make a system reliable, robust and above all simple to operate. We are very proud to have been chosen by Network Rail (High Speed) Ltd on some of their projects and my thanks go to Richard Dance and Freddie Savill who have been the best of customers. Now with a proven track record of delivering valuable data when and where it is needed we look forward to offering vanwalt CONNECT for other projects.
For critical data to protect people, property and places
www. vanwal t .com
Lewis Irvine Van Walt Ltd
Update on Passive Sampling
approaches were developed to follow the discovery that passive samples collected without purging compared well with purged results. This finding led to additional passive sampling approaches including sorption-based passive samplers and grab-type passive samplers - such as the Snap Sampler. The Snap Sampler is a passive groundwater sampling device used as a cost- saving replacement technology for both volume-based and low flow purging and sampling. What is the Snap Sampler? The Snap Sampler is a unique device that utilises special bottles that “snap” closed to collect samples from a specific and repeatable position in the well screen. The bottles are removable from the Snap Sampler device and can be submitted to the analytical laboratory directly without exposing the sample at all. This feature can yield the most pristine sample possible without artifacts from purging or surface sample handling. It is really the ideal sample for most sampling situations and especially good for difficult conditions such as low yield wells. How does the Snap Sampler work? There are a few basic components to Snap Samplers. The “Snap Samplers” themselves are the devices that hold individual bottles and contain the mechanism to set both ends of the individual bottles open. Snap Samplers can be “stacked” in a series of up to six in a row. Different sampler types allow you to collect any combination of Snap VOC vials, 125ml and 350ml HDPE bottles. The bottles are removable and replaceable. The Snap Samplers and open bottles are lowered down a well with a trigger line which can be either a manual “pull” trigger or a pneumatic trigger. Using the device is simple and
different operators. You load bottles, set the “Snap” caps open, then lower down well. The Samplers are left to quilibrate - normally the full time between sampling events. When you return to the well, you activate the trigger by pulling on the manual line (<15m) or adding air pressure to the pneumatic line (>15m). Snap Samplers are retrieved and bottles prepared to submit to the laboratory. Very simple. No purging, no waste, sample immediately and quickly. To prepare for the next sampling event, new bottles are loaded into the Snap Sampler, Snap Caps set open and lowered back down well. All equipment is stored in the well so sampling logistics are exceedingly easy to
maintain - you simply come to the site with replacement bottles and minimal equipment such as a water level meter and box for your collected samples. Advantages The main difference between Snap Sampling and purge sampling is the time it takes to collect samples. Typically, you can expect to improve efficiency by 2 to 3 times. If you currently sample 6 to 8 wells per day with purging, you can expect to collect 12-20 samples per day with the Snap Sampler. No purge waste handling also improves cost and logistical concerns. Data quality benefits can also impact your data analysis back at the office
Collecting samples in an dentical way, at the exact same depth in the well every time, with little or no sample exposure when preparing samples at the surface avoids artifacts of sampling that can make your dataset “noisy” in the long term. If you avoid those artifacts, trend monitoring becomes easier Better trend monitoring makes for quicker decisions about remedy effectiveness, attenuation rates or monitoring frequency requirements. All of these factors can have an impact on your bottom line.
Sandy Britt ProHydro Inc
Van Walt is the exclusive distributor of the Snap Sampler in the UK and Ireland.
Has “passive” groundwater monitoring come across your radar? Everyone knows that well purging is tedious and waste intensive. Low flow purging is better, but still takes time and generates waste water that needs to be handled and disposed. Increasingly we are seeing a real alternative which claims to be able to deliver cost savings as well as more consistent, accurate results, acquired safely, quickly and cost effectively: Passive sampling. Passive sampling is sampling a groundwater monitoring well using a device that is deployed in the well in advance to
“passively” equilibrate with the screen-zone water. Is that possible? Can you just sample the “stagnant” well water? In a word…. ‘yes’, because screen- zone water is not stagnant, but rather it is live flowing formation connected pore space in the subsurface, so it makes sense that water flowing through the aquifer is also flowing through the well screen. Short residence time in the well has been shown to have little or no impact on contaminant analytical results compared to purge-based sampling. The United States Geological Survey successfully introduced passive sampling using diffusion-based devices in the late 1990’s. Since that first introduction, several additional water. A groundwater monitoring well is just a
straightforward, so is easily repeatable by the same or
Confidence - Technology - Choice VAN WALT
Flexibility Confident about
Rental Workshops - Sharing expertise
The equipment needed for environmental research is becoming more and more complex. Also the models and options offered are always changing and if you are working in this field it is not easy to have to hand the best and more convenient equipment for a specific assignment. For that reason the rental department at Van Walt is becoming more and more important. Our aim is to offer to our customers
the advantages of using our rental equipment. Our aim is to be the best known provider of environmental rental equipment in the south of Europe: Spain is not a small country and our office is located in Barcelona - in the North East corner of the Iberian Peninsula. So to reach more potential customers we decided to offer a Workshop in Madrid, located in the middle of our territory and the home
PUMPS Peristaltic Pump Bladder Pump Geosub Pump MP1 Pump
questions related to issues they had encountered in the field. We were delighted to receive lots of questions so it became vital that the workshop gave us the facilities to allow active participation of everyone attending. We wanted people to ask as many questions as they wanted. Vincent was responsible for driving the Workshop and he tried from the beginning to involve the attendants, not allowing them just to be sitting down and listening! My function was to help on the translation to and from Spanish, when needed, because not all the delegates were fluent in English and this seemed to work very well. We also gave answers to the different questions people had asked when they registered for the event. An interesting issue, for example, was how to deal with the need to purge a monitoring well when the hydraulic conductivity is very low and the replenishment of the well is very slow. For that we discussed the option of low flow purging that until now is not well known in Spain, although is already the preferred technique in more and more countries, like the US and UK. Related to this was how to deal with purged waste so we discussed passive sampling techniques, where there is no purging. We showed the Snap Sampler and also we discussed the merits of adsorption samplers. These topics were quite new for
Why renting your Environmental equipment is the smart choice... some of the attendants and we discovered that these techniques are not currently used amongst Spanish environmental consultants and some interesting questions arose as a result of our discussions. We also discussed the possible problems associated with sampling groundwater with a peristaltic pump when we find there are volatiles present in the water to be analysed. This technique was not seen as the optimal solution but had the important advantage of allowing quite reproducible conditions of sampling. Overall the experience was really interesting! Twenty-one delegates participated in the Seminar, mostly from the Madrid area but also some delegates travelled from Valencia, Zaragoza, Seville and, as far away as the Canary Islands!
Before leaving the workshop we asked the attendants to complete a questionnaire: all the people answered that the topics discussed had been interesting and, what we liked more, is that people were surprised by the format of the workshop. Most were expecting a more standard commercial presentation on our extensive range of rental equipment but what they actually discovered was our different approach was really very interesting for them and allowed them to discover new ways and techniques to improve how they do their job. Now we are ready for new versions of this workshop: the 3rd of March in Barcelona will be the next event and we plan to have more in the coming months.
Geotech Peristaltic Pump Deep Well Bladder Pump
METERS YSI Water Quality Meter EXO Water Quality Logger WTW pH Data Logger Water Level Dip Meter Oil Interface Meter Water Level Logger TDR Soil Moisture Meter Compact Turbimeter GA5000 Gas Analyser REMEDIATION ATEX rated Interface Meter Total Fluids Reclaimer PID
some of the best equipment for their different projects, with the assurance that it will be clean, well maintained, serviced and calibrated the same day it is shipped. Our UK office has been the driver in establishing a rental department and the feedback provided by customers has been very important. We have used this experience and customer response when setting up the rental departments in Spain and New Zealand. At the start of 2013 we launched the rental department in Spain, and more and more Spanish customers are experiencing
of some important companies devoted to environmental studies. As soon as we told some of our customers our plan we received very good feedback! As we started to plan the content of this Workshop we realised that it would not be enough to make a simple commercial presentation of rental equipment, with some small technical tips on how & where to use it. We wanted to offer expertise on sampling methodologies, best practice and the science behind groundwater monitoring so we asked potential delegates to tell us what they wanted to hear, to ask us specific
Ricard Riera Van Walt Ltd
LEL Protection Meter Oil Interface Meter Liquid Layer Sampler
Rental Equipment Workshops Spain
Email: email@example.com for details about the next
SEDIMENT Multi Sampler Beeker Sampler Van Veen Grab
Rental Workshops Tel: + 34 93 590 00 07
Drilling with Environment Canterbury, New Zealand
In a country where there are normally mountains and rivers between you and your neighbour a small drilling system like our Lost Cone Set comes into its own. I had the pleasure of training a team from Environment Canterbury led by Bryan Todd in the use of the Lost Cone Set to install shallow water monitoring piezometers in the Canterbury region. The Canterbury region on the South Island is marked by grassy plains, clear lakes and snow-capped mountains. Its largest city, Christchurch, hosts the well-known riverside Botanic Gardens but is still recovering after the earthquakes in 2010 and 2011. To the west of the region, Aoraki Mount Cook National Park hosts New Zealand’s highest mountain as well as 27 km-long Tasman Glacier. With 42,200 square kilometres of diverse landscapes including major lakes and river systems and some of its most productive farmland, Canterbury is New Zealand’s largest region. The typical soil conditions in the area are quite variable but it is not uncommon to encounter glacial silts and gravel layers making manual drilling more tricky. The depth of the groundwater is typically 3 to 4 meters but higher levels of pollution caused by a huge expansion in dairy farming throughout the South Island which requires the intensive use of water, is putting increased pressure on environmental monitoring by the authorities who have a statutory responsibility under the Resource Management Act and the Local Government Act to protect water quality and quantity. Environment Canterbury is the regional council working with the people of the City to manage the region’s air, water and land. They are committed to care for Canterbury’s resources
and achieve a sustainable environment while promoting the region’s economic, social and cultural well-being. Working in partnership with communities they encourage the management of natural and physical resources by using innovative, cost-effective and technically excellent approaches to monitoring and research that ensures any decision making is based on high quality information and results. In the past Bryan and his team: Shaun Thomsen, David Evans, Tim McDougall and Shaun Philip have used drilling contractors to install wells but, with a need to install shallow monitoring wells on a more regular basis, the team were looking for a more flexible solution. The Lost Cone Drilling Set will do just that. It is a fast and efficient way to install a monitoring well and it works particularly well in stony soils and gravels. A specially designed cone is mechanically hammered into the soil to produce a very straight bore hole. Using this equipment makes it easier to reach depths up to 10m because the cone is slightly wider in diameter than the casing so reduces friction during extraction. The environmentally sensitive cone, made from non-toxic iron, is left in the soil after drilling. A further advantage is the compactness and portability of the kit in this large region, indeed I am surprised that there are not more of these smaller drilling kits about not just on the South Island but through the rest of New Zealand. They are ideal for drilling in less accessible areas. Training was a pleasure with these guys. They are clearly well versed in plant machinery but very attentive and respectful of special instructions. The key with this kit as always is a patient and
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Drilling with Environment Canterbury, New Zealand
methodical approach. Keep the site clear and tidy at all times, know where your hands and feet are at all times. Let the kit drill down under its own weight. In some conditions, as the casings are hammered down, they have a tendency to unwind slightly which reduces the hammering impact and can potentially damage threads. We overcame this hurdle by ‘slow dancing’ around the drill in a clockwise fashion to ensure a tight thread - but not too tight. On site the kit was slow to push through the compacted silt layers at 2 meters down but as conditions eased, moved more confidently and from 0 to 8m only took us about 45 minutes. With a large team in the training session we take advantage of hands and use four people on the extraction equipment. The lesson being with more bodies and extra kit in the immediate area it becomes even more important to work methodically. When all the casing is extracted and a fresh 32mm piezometer left in its place (placed inside the casing before extraction) the only thing left to do is road test David’s new Peristaltic Pump. Our Peristaltic Pump is the perfect complement to this type of monitoring well installation. It can lift water from up to 9m below ground level and requires only the tubing to be installed in
the well. It also happens to be the easiest pump to use in conjunction with a flow cell and water quality meter like the YSI Pro Plus to test water quality across a range of parameters. Additionally, the team have also updated their sampling capabilities with a Stainless Steel Geosub impeller type pump for jobs which require sampling from greater depths (up to 45m head of water) or where a large volume is required. Following our very productive training session I was delighted to host Bryan and his family back on my home turf of Wanaka. Bryan, on vacation in the area, dropped into our office to see behind the scenes our set-up and range of equipment available. Typically this was also during my holiday but, being at home with the kids, I was able to meet up with Bryan over a beer or two to discuss the coast to coast, north to south, island to island that defines New Zealand. For those of us lucky enough to live and work here there is an ocean of fascinating country and culture that’s unparalleled and unspoiled. It is clear that Bryan and his team at ECAN are proud to be part of the industry that maintains and protects this amazing country. So are we!
Dirk van Walt Van Walt Ltd
Soil or Sediment – how to choose the right tool
Using the correct tool: In first instance people invariably ask for a mechanised solution but as often as not a manual auger will do the job quicker and with far less effort that a heavy percussive system. If you’re doing research in the vertical distribution of Nitrates for example, then you are likely to be interested in the top 100cm (more or less the maximum root depth of arable crops). A heavy duty gouge auger, or better still a stepwise auger set which has samplers which take cores in tranches of 30 cm is light, easy to use, fast and gives excellent sample results. We have an arsenal of sampler choices, mostly developed over the years with substantial input from the University of Wageningen and if you let us know the aim of your sample taking, then we can point you in the right direction. What is evident however is that there is no “Swiss Army Knife” solution. The sampling tools have been developed with a specific task in mind. A number of staff at Van Walt have built up huge experience over the years (in my case more years than I care to admit) and we will be delighted to discuss the options with you. Ikky, Ramon, Ricard, Yvonne all have more than 10 years experience. Knowing what you wish to do with your samples: A sample which will be used to determine residual pesticides will need different treatment than a sample taken to determine the presence of volatile organic compounds. In some cases there are international standards and in other cases there are, at best, just vague guidelines. But the web is an amazing resource and because the soil sampling tools
we supply have been mostly the same for half a century there are plenty of research based publications often describing that the results are based on a particular sampling technique. As often as not, if it concerns soil sampling, they will have been using one of our samplers.
Aug er Sets
Single Edelman Augers
Vincent van Walt Van Walt Ltd
Coarse Sand Augers
Purpose: Is an undisturbed sample absolutely essential? I’m thinking of bulk density tests, root investigation studies, pesticide analysis, archaeological research which of course mostly need this but if it is a question of profiling is it imperative, because the tools for undisturbed sampling are more difficult to use and generally more expensive and often also much slower. Number of samples required: Generally PhD students want lots of samples and when they tell me they are going to collect 2000 for their project I advise them to rethink; and fast! It is better to have 20 and to do a perfect job rather than have a huge quantity just because it seems a good but unquantified idea. Nonetheless when many samples are required; for example in intensive mapping to detect the presence of metals, then this question is relevant because a mechanised system such as Window Sampling might be a best fit solution.
And so I was given just 600 words to talk about soil sampling and part of this allocation is going to be used to defend my use of the word soil. This is directly aimed at sedimentologist Professor Julian Orford who figuratively rapped my knuckles over my misuse of the word and somewhat spoiling my excellent curry in the Oberoi Hotel in Calcutta (Kolkata before I get another telling off). The ensuing argument between the eminent professors Orford and Bennet at least gave me a cause for an internal chuckle. 5% Discount
Be that as it may, as I’m also charged with writing an article on sediment sampling I will make the distinction here. For the current purposes, I’m referring to soils as all the harder sediments and exclude peats, sludges, mud and low density materials. This distinction is important because the sampling tools are very different. When choosing a soil sampling device a decision has to be made according to the following:
Stony Soil Augers
Single Gouge Augers
Bulk Density Rings
Single Gouge Auger Sets
Peat Sampler/Russian Corer
Gouge Auger Sets
Stepwise Sampling Set
Chemical Coring Kit
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Bugs, floods and farms...
... disentangling the influences on hydrology and ecology in coastal wetlands. Wetlands are places where water is close to the surface and influences chemical and physical processes and biological communities. They provide a different set of resources from other terrestrial habitats, so in arid regions in particular, they support plants and animals which would otherwise be absent from the landscape. In north-west Europe, sand dunes are as close to an arid environment as you are likely to encounter. Between the dune ridges there are valleys or slacks, some of which are so deep that the water table is always close to the surface and they flood for months in winter. These ponds are isolated from other surface water, essentially acting like wet islands of habitat. In summer, when the ponds dry out, the flora and fauna have to be able to tolerate the dry conditions or escape. This strong influence along with the calcium rich substrate and nutrient poor water has led to dune slacks having a very characteristic plant community. Invertebrates are vital to the functioning of wetlands, breaking down detritus, processing nutrients and providing a food source for other animals, but we know very little about what invertebrates are using dune slacks. Dune slacks are protected under the EU Habitats Directive and their condition must be monitored every six years. Plant species are used as indicators of general habitat condition, but if plants respond differently from invertebrates to changes in the environment, this could mean
that threats to invertebrates are ignored. Water availability and quality have been shown to be key environmental factors determining the plants and animals which use wetlands. In this project, I want to find out what environmental factors affect the hydrology of dune slacks and how environmental factors including water affect diversity of plants and invertebrates in dune slacks. The study sites were located in County Donegal in the far north west of Ireland, where sand dunes are well developed and potentially confounding factors such as atmospheric nitrogen deposition and water abstraction for domestic use have a relatively low impact. Three dune slacks managed as pasture and three ungrazed sites located in rough areas on golf courses were selected. All of the pasture sites were within SACs and enjoy some legal protections. Water abstractions and the use of inorganic pesticides and fertilisers are discouraged. The vegetation is shorter and more disturbed than in the golf courses and there is some direct input of organic nutrients from livestock. In the golf courses, the dune slacks had tall, dense vegetation and water is abstracted for irrigation and use in clubhouses. Inorganic fertilisers and pesticides sprayed on greens and fairways may penetrate to the water table. At each site, two piezometers were inserted into the dune slacks to a depth of 3 meters below the surface using a Cobra TT percussion drill. Water samples were taken from the groundwater and surface water when it was present in October 2014, January, March and June
2015 and tested for a range of nutrients, alkalinity and major anions and cations. Water levels in the wells were monitored for the period of a year using Water Level Loggers which recorded the water level once every 15 minutes. Vascular plants and bryophytes were surveyed at each site and snails and water beetles were chosen as the target invertebrate groups. Snails and waterbeetles were chosen because they are both sensitive to environmental degradation, can be identified to species with a strong degree of certainty and they have contrasting biological traits such as degree of mobility and feeding habits. My preliminary results indicate that values for salt content, pH, alkalinity seem to be well within the range reported elsewhere, with the exception of one site where one of the wells showed signs of seawater intrusion. Nitrogen content is at the lower end of the range for groundwater reported in literature. One of the sites failed
to flood for the entire year, and this is likely to be related to the abstraction activities of the golf course management where the site is located. The highest recorded water level was 1.68m. Water generally rose above the ground surface in late October or early November, and they remained flooded untill the following April at the earliest, although it was not uncommon for surface water to be present in June. At a single site, shallow surface water was still present when it was visited in October 2015. Snails were far more abundant than water beetles and both terrestrial and aquatic species were found. I have entered an exciting phase, when the data has been gathered in and is beginning to reveal patterns and processes about the system. The sites are very variable both in terms of their water chemistry and flood period. My next challenge will be to investigate the local processes which may account for the differences I have noted between the sites, in the hopes of explaining at least part of this
variation. I will also investigate the diversity of snails and water beetles at my sites, and seek to relate the number or type of species I find to the flood duration and chemical profile of the dune slack water. For me, relating biological communities to hydrology is the main focus of this work, but the results will help to shed light on other questions. Because sand dunes are made up of a network of Annex I habitats, I can provide insight into the influence of landscape factors on water quality in sensitive environments. Because sand dunes are the last terrestrial landform groundwater travels through, the information I have collected on groundwater quality will contribute to our knowledge of nutrients transport from the land to the sea. But for the moment, I have plenty on my plate, and look forward to drawing together the three strings of landscape, hydrology and ecology over the next nine months.
“Thank you so much for the help and equipment that Van Walt have provided for this part of my project. The system has been user- friendly, the data seems very good and consistent, and the support was very valuable. Being able to incorporate detailed hydrological information from several sites simultaneously really sets
my research apart. I am very grateful.”
Aoife Delaney, PHD Student Trinity College Dublin.
Aoife Delaney Trinity College Dublin
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