As of September 1, Marco van den Brand has taken on the management of WeGroSan/hmvt (WGS) in Belgium. WGS is a full subsidiary of HMVT and focuses on (in-situ) soil remediation and various traditional civil projects. With direct management from HMVT, knowledge, people and resources between WGS and HMVT will be optimized.

Marco: “I’m really looking forward to it. I think there are many opportunities for HMVT in Belgium, not only in terms of soil and groundwater remediation and filling stations, but also in the field of vapor and water purification. are active in the Netherlands. In addition, we are also able to distinguish ourselves in Belgium when it comes to taking over remediation obligations. In short, there is plenty to do!”

Toekomst Naar de toekomst WGS zich vooral gaan richten op in-situ en klassieke bodemsaneringen en de bouw en verbouw van tankstations.


In the future, WGS will mainly focus on in-situ and classical soil remediation and the construction and renovation of filling stations. We focus on complex contaminants where, for example, a lot of cargo has to be removed or where explosion safety is an issue. We use all conceivable techniques for this, ranging from extractive, biological or chemical, but also thermal if necessary. we will also bring the experiences of HMVT in design, construction and operation of Constructed Wetlands for groundwater treatment, Japanese Knotweed projects and Off-the-Grid remediation installations to Belgium. With regard to the construction/renovation of filling stations, we will also apply the Dutch experiences with regard to electric and hydrogen stations.

More information

For more information, please contact Marco van den Brand.

An industrial theme housing that totally follows the latest trends. This is where an industrial interior belongs, as well as industrial surroundings with an industrial heritage. A very successful example of this is the Defence island in Woerden. The soil in industrial areas is often contaminated because of intensive use. This was also the case on Defence island. The property developer of the location had first to decontaminate the soil in the area before transforming it into this unique place of residence.

The location

This contaminated island in the inner-city of Woerden was a military complex from 1880 to 2001 where, amongst others, clothing and equipment were washed. Because of the industrial activities, both the soil and the groundwater at the site were contaminated with chlorinated hydrocarbons. After cleaning up the contamination in the upper layers of the soil, HMVT, the in-situ decontamination specialist, decontaminated the groundwater.

Decontamination techniques

On the island, three source zones were identified together with a large scale pocket layer. Before construction could commence, the source zones were decontaminated to a depth of 5m-mv through excavation. Thereafter, HMVT treated the underlying soil layer from a depth of 5 to 20 meters with the aid of in situ chemical oxidation. Following this treatment, most of the contaminated substances were transformed into harmless end products. In some places, this treatment was repeated up to five times. Subsequently, a ‘polishing step’ was initiated by stimulating the (anaerobic) breakdown of the remaining contamination by the administration of a (slow release) carbon source. In layman’s terms: we created the ideal environment for the bacteria so that it could further break down the remaining contamination. The decontamination of the soil has now progressed to such an extent degree that the Competent Authority has given the go-ahead for the commencement of the development. We are really proud that we were able to take on this challenge and, together with all the parties involved (see image below), to convert it into a successful result.

Out of the box

Each project is unique and HMVT likes to think along with those involved to find a bespoke decontamination solutions. With soil decontamination it is often difficult to make a good estimation in advance. To what depth has the decontamination spread? Which types of soil layers are present? Which toxic substances are involved? If it turns out that the area is larger than expected, we anticipate this in a flexible manner. Together with you, we think further. Are you curious about what we could mean for you? Then please contact us.

Constructed Wetlands can be a beautiful, energy-efficient and circular method to purify contaminated groundwater streams and percolate water originating from disposal sites. We have already designed and produced many Wetlands. Last year, we also built a model for better dimensioning our Wetland beforehand; this spring, we constructed a mini-wetland in a 20-foot container. This pilot unit can be taken to a location to determine the feasibility of this treatment method on-site and verify the site specific design parameters. We can also collect water and test it ourselves at Ede.

The Constructed Wetland Pilot Unit .is now operational. On the 9th of July the unit was installed at the Nedereindse Plas site to conduct a pilot. Despite the clean-up of this former disposal site, contaminated percolate water flows into the groundwater, and this pollution is managed. The current water purification system needs an update, and we think that it can also be replaced by a Constructed Wetland. We will be testing in the coming months to determine if this is indeed the case.

We are conducting measurement campaigns with our clients more and more often to advise them effectively and for more exact dimensioning of a vapour decontamination solution. As HMVT, we go through the whole process thoroughly, not only for soil and groundwater projects but also for air projects: consulting, measuring, testing, designing, production and operation.

More insight

Our aim is to provide the (industrial) client with the most suitable vapour purification solution with a minimal footprint. Often this process would start by getting more insight into emissions. However, these insights are often not obtainable. However, you do regularly see that a (point) measurement or occasionally an odour survey has been done, but to determine the optimal vapour treatment method, it is also crucial to get insight into the dynamics of the vapour emissions: where the increases and decreases are. Not only during the day but also by night and preferably for a duration of a few weeks. Obviously, this will depend on the operating process.


We have two mobile FID units to help us obtain this insight; the one is a two-channel unit, and the other is a four-channel unit. Explosion-safe suction tubes are also available if required. These FID units are also used regularly in our mobile vapour decontamination project with our partner Reym. An FID unit ‘counts’, so to speak, the number of carbon atoms in one vapour. Thus, it is a highly robust unit for determining vapour concentrations.

The photo illustrates the FID setup in a measure and observance container of a vapour decontamination test conducted in Helmond. To further expand our capabilities, we will house the two FIDs in trailers in the coming months to be connected and started up on-site in a plug-and-play fashion.

As HMVT, we want to be a frontrunner and co-innovator for soil and groundwater decontamination. And this year was very busy for us as we organized one session and gave two presentations at Symposium Bodem Breed and two presentations at Aqua Consoil. The Bodem Breed presentations can be viewed again on YouTube by participants. In the coming months, we are aiming to share our presentations with you via our news channel.

Watch our presentation

In this regard, we already have one presentation from Wouter Neutel about the successful purification of the soil ‘decontaminated’ by Japanese knotweed. After a successful test run in Rotterdam, we are currently conducting an on-site decontamination project in Amsterdam. Also there our method seems to be able to remove the knotweed sustainably. Something really unique in this market! [click here] for the presentation.


We are not at Symposium Bodem Breed and Aqua Consoil. On 24 November, we will present at the congress ‘Groundwater, from blue gold to code red’ in Utrecht. Our argument will be that it is sometimes better to clean up sources than just risk-based monitoring/management.

Lately, we have strengthened our teams substantially to keep our projects ‘afloat’. Martijn Baars has already been working for us for one year, albeit in a detached external capacity as Water Manager. Recently, he has been made responsible for the construction of the facilities in our workshop. Additionally, he does internal and external consulting for water purification solutions, and in collaboration with our internal planning and workshop colleagues, he is in charge of improving our purification solutions to an industrial standard.

Not only project managers but also young technicians have joined our team. Two junior technicians have joined our team recently: Carl Geerlings and Ferry Kourer. These youngsters are receiving training in our workshop and will definitely also be helping out on projects in the field. And then we also have Arthur Rensen, who will be helping us to automate our Equipment Management System for the foreseeable future. A word of introduction.


Ferry Kourer

Ferry has been with HMVT for one month after working for several years at the Dolfinarium.

Ferry: ‘the work is really cool, great colleagues, diverse and very technical, exactly what I wanted and was looking for’



Carl Geerlings

Carl just started working with us at the beginning of the Corona Crisis, and then we had to let him go, unfortunately. But he wanted to come back, so since the start of the month, he is part of the team again!

Carl: ‘Back in Business, I’m really in my element here, and hope to learn much more’. 



Arthur Rensen

Last but not least, we’ve had Arthur with us for some time as well. Arthur is helping us with one of the most challenging tasks we have… setting up and filling our new Equipment Management System. The old EMS system requires some updates, and in the new Track &Trace system, we want to register each item with a barcode.

Arthur: ‘my word, it is more work than I thought, but really cool’



Our Belgium team is looking for an experienced senior project manager to strengthen our environmental team. Click here for more information and contact us for a conversation, without any obligations!

Martijn Baars, who is maybe already a familiar name to you, is now fully employed by HMVT. With many practical experiences in water purification, for instance in the pharmaceutical industry. Now, he’s devoloping new water purification systems for HMVT. Martijn: “Marco asked me to take a fresh look at the water treatment plants of HMVT. That’s a ncie challenge and I am eager to take efficiency and reliability to an even higher level.” HMVT is also committed to energy-efficient water purification, where possible biologically or circularly, such as with the help of constructed wetlands.

Different installations, one goal

Martijn worked for several years in the pharmaceutical industry as a construction manager and process engineer. How do you purify water with medicine residues? Just discharging waste water into the sewer is no longer of this time. Martijn: “It’s great to see that you can make progress on larger projects by working together. For example, I remember a great project where we had set up a lot of different equipment with a number of companies. Each device had its own function, but the goal was clear: clean water. Projects like these give you the experience and knowledge that will benefit you throughout your career.

New job with familiar faces

Marco and Martijn got in touch by seeing each other in several purification projects.  Marco: “That man knew his business and I wanted a second opinion about HMVT’s water purification systems. He was still working fulltime in the pharmaceutical industry for some time, but now he is fully available for HMVT . A great new strength in the HMVT team.” The switch to a new job is a nice new challenge, but it’s also difficult at times. Martijn: “I feel completely at home at HMVT, but at the beginning it is sometimes difficult with suppliers. I was so convinced of the quality of some suplliers, that I recommended them to HMVT. That has ensured that I occasionally see a familiar face from the past.

Work in progress

In the past year and a half that Martijn has been employed by HMVT, he has already been involved in several great projects. Martijn: “In addition to being asked for my critical view of the existing water treatment plants, I also wanted to tackle my first projects. We succeeded: designing a purification system for a washing station with different water contaminants.” The contaminants at this washing station often differ. Machines and equipment from various sectors of food, pharmaceuticals, agriculture, but also from the petrochemical industry. Martijn: “That’s exactly the challenge of this project. I’ve been busy designing a water purification system that you can easily set up per machine. A machine to be cleaned from the oil industry requires a different purification than a pharmaceutical one.” Reactions to Martijn’s design have been positive, so HMVT expects to start building the water treatment plant soon.

Contact us

Do you have any questions for Martijn? Feel free to ask them via

There is a great need for technically trained personnel in the Netherlands. At HMVT we look to the future. We are always looking for young, talented engineers. We can learn so much from each other. This is also evident during the technical internships that we offer. The interaction of knowledge provides a sharp, fresh perspective.

To encourage young people to choose a technical education, HMVT is a friend of TechnoDiscovery. This new learning and discovery center in Ede allows students to come into contact with different materials and modern techniques. In this way, young people discover at a young age how beautiful and varied the profession of technology is. The demand for technical personnel is increasing. In this way we respond to this question and let young people get acquainted with perhaps their passion for the future in a pleasant way.

As presented by HMVT and Deltares at the Aqua Consoil Conference in Antwerp in 2019 [link] and widely recognized amongst groundwater specialists, our common groundwater slowly becomes ‘grey’. Within our society there is a growing awareness that our precious drinking water supplies are under threat by diffuse and emerging pollutants like pesticides, nutrients as well as medicines and PFAS. In contrary to the ‘classical’ soil- and groundwater pollutants such as chlorinated solvents, heavy metals and oils these ‘new’ pollutants are not only found as hot spots in densely populated areas but also in rural areas. These compounds are found in big volumes with low, but still significant concentrations. Diffuse pollutants like these not only threaten drinking water supplies, but also process water and other sources that are used in (food) industries.


Combined Strengths

To remove pesticides and medicines from water Advanced Oxidation technologies like UV/peroxide or Ozone combinations can be very effective as a treatment method, both technically as well as financially. This is also why HMVT and Van Remmen UV Technology have joined their forces on this topic. HMVT has over 25 years of experience in in-situ soil and groundwater remediation projects, varying from conceptual design, modelling and pilot studies to implementation and operation of treatment projects. Van Remmen UV Technology on the other hand is specialized in water treatment with AdvanoxTM (Advanced Oxidation Technologies), also ranging from design to construction and operation of the actual water treatment systems. Together we form a very strong team to help organizations in protecting their precious (drink)water sources from medicines, pesticides and other micropollutants.

More information?    

Do you have a case where pesticides or medicines in groundwater need to be treated, please feel free to contact us. This can be done via Marco van den Brand or via Kaspar Groot Kormelinck.

At a petrochemical site in Europoort, HMVT successfully completed an extensive NAPL layer remediation within the estimated timeframe. The NAPL layer consisted of approximately 6,500 m2 of crude oil and was up to 80 cm thick in some places. It was located at a tank farmyard. The NAPL layer was also present under the tank.


The remediation was carried out through Multi-phase Extraction (MFE). In MFE soil air, contaminated groundwater and the NAFL layer are removed through a network of underground extraction filters by applying high negative pressure. In total, 440 extraction filters were installed at the location. Some of the filters were placed under the tank during the renovation of the tank mound. The tank was jacked up at the time. Through NAPL layer measurements and close monitoring of the process parameters, a continuous effort was made to use the installed system as optimally as possible. The extracted soil air was purified with two catalytic oxidation units. The contaminated groundwater was discharged into the industrial sewer via an oil-water separator. The pure product was periodically extracted from the oil-water separator and transported to a processor.


During a period of 3 years, more than 10.000 kg of crude naphtha was removed from the soil. After those 3 years, the NAPL layer had disappeared, and the volatile components were remediated from the groundwater. After a stop test, DCMR approved the achievement of the remediation objectives. HMVT is proud to have been able to complete this extensive remediation with good results.

More information

Please contact Ted Vendrig.