How To Inspect Your Ground Water Monitoring Wells

Nick Caltabiano at NEO Consulting provides insight on why keeping your wells maintained really matters.

Regular maintenance and required inspections are crucial parts of keeping your petrol station not only running smoothly, but also ensuring that your petrol station is meeting all of the requirements put forth by your state. Pumps and tanks each have their own maintenance and inspection policies, but perhaps one of the lesser thought about areas of inspection is your petrol station’s ground water monitoring wells.

We spoke with one of our partners, Nick Caltabiano, at NEO Consulting for his expert insights on ground water monitoring wells. Nick provided us in-depth answers to a series of questions, including the functions and importance of your water monitoring wells, and the best ways to maintain and inspect them. He also gave us a good idea of what could go wrong if you fail to seek regular inspections, and the benefits of keeping your inspections up to date.

What are ground water monitoring wells?

Ground water monitoring wells are the wells which allow ground water to flow and assess the condition of the ground water beneath the site. These wells are predominantly 50mm diameter vertical pipes, generally located on the perimeter of the service station. It is best practice to have two such wells down gradient of the underground tanks, and one which sits on an upward gradient of the tanks.

Many petrol stations also have, or are limited to having, Tank Pit Observation wells, which should not be mistaken for ground water monitoring wells, as they do not intercept ground water beneath the site, and sit only within the tank pit.

Source: NSW EPA guidelines

Are ground water monitoring wells required in every state?

These wells are required on site at every service station in NSW. However, in Tasmania, ACT, Victoria, QLD, SA, NT, and WA, they are only required in certain areas. These areas are determined by an Environmental Consultant on a site by site basis. Often, banks connected to your service station may have their own requirements you must meet in order to secure funding for your petrol station.

In accordance with Australian Standards AS 4897-2008:

The design, installation, and operation of an underground petroleum storage system confirms that it is a requirement to have a leak detection system in place. A leak detection system can be in the form of:

  • Automatic Tank Gauging
  • Statistical Inventory Analysis
  • Interstitial Monitoring
  • Line Leak detection for pressure piping
  • Ground Water Monitoring

Are petrol station owners required to have their wells checked by a third party?

Yes, they are! All wells must be assessed every six months by a ‘duly qualified’ consultant. Ground water monitoring wells must undertake laboratory analysis within 30 days of installations. If the wells are found to be clean and clear, then the site can engage a third party to perform a visual assessment of the wells every six months.

If the site operator suspects any contamination, or the initial lab or visual assessment finds contamination, then further investigation and laboratory analysis may be required.

What does a basic inspection look like with NEO?

A basic assessment of ground water monitoring wells includes the following steps:

  • The cap is opened and a PID (Photoionisation Detector) is used to assess the air within the well as quickly as possible. This gives us an initial idea as to if fuel vapour is present within the well.
  • Water levels sensors are then used to record the depth of ground water within the well. Depending on the depth of ground water, underground tanks may be sitting in water. Once the depth of the ground water is known, the flow direction can be determined.
  • Then, the depth of the well is recorded which allows us to calculate the volume of water within the well.
  • The water quality is then assessed visually using a clear view bailer. If contamination is present, then a sheen on the water surface may be apparent. Fuel products may also be visible floating on the water’s surface. This phenomenon is sometimes referred to as LNAPL, or Light Non-Aqueous Phase Liquid.
  • Lastly, the well is reassessed using the PID to determine whether or not levels of vapour have increased or decreased during the assessment. If laboratory samples are required, they are taken using a low-flow pump method, or a Hydra-Sleeve.

In your experience, what are the ramifications if sites do not install the wells, or fails to have them regularly inspected?

This question has a variety of answers. Firstly, ramifications from governing bodies are generally not as severe as resulting property value loss when it comes to regular inspections. For example, in 2020 NEO was involved with an owner of a petrol station site which did not have wells. The owner was approached by a potential buyer, and after negotiation, one of the conditions for the contract was that the site is ‘compliant with current regulations’.

Considering the site was in NSW, installation of ground water monitoring wells was required to meet regulations. When NEO arrived to do the installation, fuel was encountered within the soil and groundwater while drilling, and the project was halted. Because of this, the current owner was stuck undertaking tank and line integrity testing, which cost him upwards of 15k. The issue was then found to be a tank failure which required tank replacement. When his bank found out about the issues, they requested he undertake a full environmental investigation to determine the extent of contamination and determine the liability of the site.

When all was said and done, the owner spent upwards of 300k. Though the sale went through, the agreed upon price ended up being significantly lower than originally determined due to the liability for the buyer.

Failing to have or to maintain your ground water monitoring wells can result in contamination which, when not caught early, can result in significant contamination requiring full assessments to determine if it is contained, or if the contamination ‘may be leaving the site’. If it has, then local and community councils may get involved. At the end of the day, Installation and upkeep of these tanks can save you a great deal of time and money later on down the road.

Are there any other benefits to regular checks?

Most banks request a recent history of six month inspection reports if you wish to borrow money or refinance your business. Performing regular checks of your wells will allow you to show your bank that your site is clean, and that you are undertaking your due diligence as an owner and operator, making interactions with your bank much easier.

What kind of feedback do you get from petrol station operators who currently go to NEO for inspections?

We have found that in sites we inspect every six months, we are able to identify and monitor any potential contamination before it becomes a larger issue. Recently, a site we regularly inspected which had formerly shown no issues suddenly presented approximately 2mm of fuel on top of the water. We notified the owner immediately, and the entire site had integrity testing completed, where they determined that a tank in the tank pit had failed. Within two weeks, the owner was able to get the tank relined, and the site was back in operation.

Due to the speed of response, NEO Consulting was confident that the source of contamination was no longer present. The site then undertook a purging program where all wells onsite were pumped empty regularly for three months. Six months later, the site has no issues and is back to presenting wells that are clean and clear without the Council, EPA, or bank ever requiring a notification.

Regular monitoring from NEO ensures that our clients can have peace of mind knowing that any problems that may present will be caught early, and taken care of, saving them time and money and preventing a small problem from becoming a total headache.

ServoPro members are able to access the services of NEO Consulting at a special rate. For more information call Dan Armes on 0490 415 063 or email [email protected]

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