This guidance explains what Check Your Groundwater (CYG) areas are, how they protect your health and safety, and how we identify them.
This information is helpful if you:
- want to use groundwater
- live in or near an area with impacted groundwater quality
- manage or control sites we identify as the source of groundwater contamination
- are an environmental consultant or a government body needing to understand the environmental condition of groundwater.
Groundwater is the water that collects or flows beneath the soil surface. It fills the porous spaces in soil, sand, clay, and rocks. Groundwater is accessed using a bore. A check your groundwater (CYG) area is an area where groundwater is known to be contaminated. This means the quality of the groundwater may not be suitable for some uses. It may be harmful to human health and the environment. Learn more about groundwater contamination.
What is a GQRUZ?
A Groundwater Quality Restricted Use Zone is the name that was used under previous laws before it was changed to Check Your Groundwater area.
GQRUZs were placed on sites where an environmental audit had been done and it showed that groundwater contamination remained following clean up.
All GQRUZ can be considered to be a CYG area at post remediation status. This is because we were satisfied groundwater contamination was cleaned up to a suitable standard at the time.
Why we identify CYG areas
We use CYG areas to inform the Victorian community about known groundwater contamination. CYG areas help with the awareness and management of contaminated groundwater. We identify a CYG area when groundwater is found to be contaminated by an activity, waste, pollution or contaminated land. We consider if contaminants are reported above the environmental values in the Environment Reference Standard 2021.
To understand more, read our Guide to the Environment Reference Standard.
Find a CYG area (or a GQRUZ)
Visit Victoria Unearthed to find a Check Your Groundwater area near you. Victoria Unearthed is a database owned by the Department of Energy, Environment and Climate Action (DEECA). It shows information on contaminated land and groundwater. It is free to use and available to all Victorians. When we create a CYG area this information is provided to DEECA to share on Victoria Unearthed.
The map provides information on:
- what uses the groundwater may not be suitable for. For example, whether it’s unsuitable for drinking or watering gardens
- the risks of using or coming into contact with the groundwater
- how far the contaminated groundwater area extends
- the accompanying assessment report (where available), and
- a link to view and print a one page report showing the location and information.
Not all areas of groundwater contamination are known
If the location you are searching does not have a CYG area, it does not mean that groundwater is suitable to use. The groundwater may not have been tested.
We suggest you test for a broad range of contaminants before:
- extracting groundwater for use
- irrigating for plants and crops
- dewatering (pumping of groundwater) for construction
- other activities where contact with groundwater is expected.
The status of a CYG area
A CYG area may have one of three statuses. The status will be displayed on Victoria Unearthed. The status helps you understand how much investigation and clean up of the groundwater has been undertaken. They are:
- Post remediation: Clean up of groundwater has occurred but some groundwater contamination remains. All GQRUZs have this status.
- Under assessment: Further monitoring, evaluation and/or remediation of the groundwater is expected.
- Precinct: The source of groundwater contamination is not clear. There is evidence that it comes from multiple sites. Clean up of the groundwater cannot be effectively completed.
The requirements and responsibilities where there is a CYG area stay the same regardless of the status. Users of groundwater within a CYG area need to make sure the groundwater is suitable (i.e., test it) before using it.
A status only applies to areas of contaminated groundwater identified after 1 July 2021. Previously, we had the ability to officially identify zones of contaminated groundwater. These were known as groundwater quality restricted use zones (GQRUZ).
Living in or near a CYG area
Where a contamination source is known
A person who owns or manages land that is a source for groundwater contamination must tell you if you’re living in a CYG area and provide regular updates to you. This is a part of their duty to manage contaminated land. They are also responsible for the clean up and management of the contaminated groundwater. We will share the CYG area on Victoria Unearthed.
Where a contamination source is not known
In some cases, it is difficult to find the source of groundwater contamination. Our role is to ensure you are informed, and to share the information about the impacts to groundwater quality via a CYG area. There may be many sources for the contamination. For example, areas that have been used for market gardens for many years. This is an example of a precinct status CYG area.
It is important for anyone wanting to use groundwater in these areas to test it to ensure it is safe to use. As there is no source identifiable, we may not be requiring any clean up or monitoring.
What a CYG area means for you
A CYG area will tell you what the groundwater may not be suitable to be used for.
You can still use water from a town supply or rainwater.
Protect your health if you are living within a CYG area
1. Test your groundwater if you want to use it
If you’re living in a CYG area and use a bore to extract groundwater:
- Stop using the bore water immediately for the unsuitable uses listed on the CYG record in Victoria Unearthed
- Get the bore water tested to confirm if it’s suitable to use.
- If testing shows it’s not suitable, either don’t use it or treat it before use.
Consult a qualified environmental consultant to get your groundwater tested by a NATA-accredited chemical analysis testing laboratory.
2. Volatile chemicals
If there are volatile chemicals (chemicals that give off vapours) in groundwater, this may pose a risk. If contaminants are not volatile, there’s no risk to your health if you do not extract the groundwater. Information about the risks from volatile chemicals in groundwater should be provided to you. You can contact us if you have any questions or concerns.
3. Shallow groundwater
In some areas groundwater maybe shallow, such as less than 3 metres below ground surface. We advise you to wear protective clothing / gloves if there is a possibility of exposure to avoid direct contact with the contaminated groundwater. Be careful when:
- digging holes for planting or posts
- digging trenches or deeper excavations
- maintenance workers are installing utility services and/or doing repairs
- incidental direct contact, for example a leaking basement or wet wall basement.
Get specialist advice
1. Investigate management measures
We recommend you talk to a qualified environmental consultant with groundwater expertise.
2. Corrosive groundwater
Contaminants in groundwater can be corrosive and may affect buildings and structures, for example, concrete and steel structures and basement waterproofing membranes.
If corrosive groundwater has been identified in your area, we recommend you get advice from a qualified builder. They can help you understand if you’ll need any additional requirements during construction or if you have concerns about any existing structures.
Be aware of certain activities
If you live in or near a CYG area, some activities may impact the behaviour of the surrounding groundwater. For example, if you’re undertaking earthworks that intersect or are below the groundwater level, consider:
- if you need to dewater (pump groundwater)
- how this may affect groundwater flow direction
- if it may draw groundwater contamination from a neighbouring site
- vapour risk if the contaminants are volatile.
If you’re using or intercepting groundwater near a CYG area, be aware that contamination may extend onto your site.
If you encounter unexpected contamination in groundwater, report it to us.
Developing your land
If you’re planning a new land use or development in a CYG area, think about how it might expose future structures or users to the contaminated groundwater.
The land may be classified as 'potentially contaminated' in the land use planning system, triggering specific requirements.
Read Planning Practice Note 30 - Potentially Contaminated Land for guidance. This includes information on uses and adjacent uses with the potential to contaminate land.
Buying land in a CYG area
If you are buying a property in a CYG area, the current owner should tell you about the CYG. You can also check Victoria Unearthed to see if a property has a CYG area.
Your legal duty
By law, you must do everything you reasonably can to minimise the risk of harm to human health and the environment. This is known as the General Environmental Duty.
To meet your General Environmental Duty:
- read our information on groundwater contamination and ways to lower your risk
- take steps to minimise the risk when you’re doing anything that might contaminate groundwater, for example:
- storing or handling chemicals above ground
- storing chemicals in underground storage tanks
- minimise the risk of exposure to contaminated groundwater when:
- extracting groundwater
- digging a hole that might contact shallow groundwater
- dewatering activities that change the way the groundwater contamination moves
- undertaking groundwater remediation. For example, direct injection of remediation chemicals, or pump and treatment of contaminated groundwater.
Any activity that moves groundwater contamination may be a breach of the General Environmental Duty. For more information read our guidance on the General Environmental Duty.
Managers or controllers of source sites of groundwater contamination
You have a duty to manage contaminated land
When you have identified impacts to groundwater quality, meaning there is a risk of harm to human health or the environment, it meets the definition of contaminated land. This means you have a duty to manage the contamination. This means you must:
- manage the risks associated with the contaminated groundwater. This may include further assessment, clean up, ongoing monitoring or other administrative approach
- communicate with any offsite stakeholder who is likely to be impacted by the contamination, and any future owners of the site.
Your duty to manage contaminated land remains while there is a CYG area in place.
For more information, download our guide to the duty to manage contaminated land.
You may have a duty to notify of contaminated land
Where you find contaminated groundwater, you may need to notify us. We will use the information in your notification to decide what regulatory action is appropriate.
If notifiable contamination exists, you must still notify us where:
- an EPA remedial notice has been issued for your site
- there is an active environmental audit.
You do not need to notify us if:
- the remedial notice was issued or the environmental audit was completed before 1 July 2021, and
- there has been no material change in the condition of the land.
For more information visit, Guide to the duty to notify of contaminated land.
Communicating with offsite parties
When you’re talking to offsite parties, we suggest you engage a qualified environmental consultant to help.
You must inform offsite parties when you become aware of contaminated groundwater that extends off your source site. Informing offsite parties should happen without delay.
When you get a remedial notice, we may want to review your communications with offsite parties.
You must inform anyone that may use or encounter contaminated groundwater from your site. This includes:
- site owners and occupiers of any private properties
- the owner's corporation for multi-dwelling properties
- owners or occupiers of other land, for example, council or Vic Roads
- utility owners with assets where groundwater is shallow (less than 3 metres deep). For other scenarios, assess the likelihood of the utility owner to access groundwater and contact them on a case-by-case basis.
You should disclose:
- Sufficient information to identity the contamination
- Results of investigations and assessments
- The risk of harm to human health and the environment
- Enough information so they can comply with their duty to manage contaminated land.
Below are some suggested structures to your communication.
1.When you become aware that contaminated groundwater extends off your site
Purpose:
- Advise neighbouring impacted parties that there is contaminated groundwater at their property.
- Help them reduce the risk of harm to human health and the environment.
- Inform them of their duty to manage contaminated land.
Advice:
- Groundwater may pose a health risk if extracted. There is no risk if they do not extract groundwater (if the contaminants are not volatile).
- If the groundwater is shallow: groundwater may pose a health risk if you come into direct contact with it.
- If contaminants are volatile: detail any potential vapour risks or considerations.
- Links to EPA guidance about the duty to manage contaminated land and groundwater.
- Investigations to date and results.
- Any other contamination at the site.
- Maps or figures showing the extent of contamination and groundwater flow direction.
Next steps and any future clean up and management proposed.
Your (or your representative's) contact details for any questions or further information.
2.When we are assessing a CYG area at your source site
We will contact you when we are assessing whether to identify a CYG area.
If the proposed CYG area extends offsite, you must tell all impacted parties.
The purpose of this communication is to keep all stakeholders informed. It allows them to get further information and provide feedback about the proposed CYG area.
You should:
- confirm with us when you have sent the communications
- allow 2 weeks for impacted parties to provide any feedback to you
- provide any feedback to us for consideration.
Suggested structure
Purpose:
- Advise them that EPA is assessing whether to identify a CYG area that includes their property or asset.
- Provide information on what a CYG area is.
Advice:
- A CYG area will not mean town water supply or rainwater is affected.
- Links to EPA guidance about CYG areas, groundwater and the duty to manage contaminated land.
- A reference to any communications with the stakeholder about the contamination.
- Information on the current state of the contamination, including potential risks.
- Figure showing the extent of the proposed CYG area.
- Next steps including future clean up and management proposed.
- Your (or your representative's) contact details, and EPA officer contact details for any questions or further information.
3.When we have identified a CYG area at your source site that extends offsite
Purpose:
- Advise that EPA has identified a CYG area that includes their property.
Advice:
- The site owner must tell prospective purchasers about the CYG area as part of their duty to manage.
- Links to EPA guidance about CYG areas, groundwater and the duty to manage contaminated land.
- A copy of the CYG area map.
- Your (or your representative's) contact details for any questions or further information.
Need help engaging with the community about risks?
See Volume 20: Schedule B8 of the National Environment Protection (Assessment of Site Contamination) Measure 1999.
What information we consider
To identify a CYG area, we can use information from environmental audits where:
- groundwater has been cleaned up, but contamination remains. For example, a suitability of land use audit
- groundwater has been assessed as part of the environmental audit. For example, a risk of harm audit
- historical environmental audits where GQRUZs have been recommended
For sites where the groundwater has been cleaned up as far as reasonably practicable, see the checklist of information required in appendix A of EPA Publication 2001.
Changing or removing a CYG area
When future groundwater assessment and investigations show that a CYG area has changed, we can:
- change the extent of a CYG area boundary
- remove a CYG area.
We require supporting evidence to do this. This could be assessment reports showing:
- the size of a plume extent has changed
- groundwater quality is no longer impacted. That is, all the relevant environmental values of groundwater are achieved or maintained.
Examples of information sources EPA may use to change or remove a CYG area include:
- assessment reports in response to remedial notices
- follow up to contaminated land notifications
- environmental audits
- cessation of groundwater monitoring reports, for example, from a groundwater quality management plan.
More information
Download the CYG area point and polygon datasets from:
If you have problems accessing the data, email contact@epa.vic.gov.au or call 1300 372 842.
Any information contained in a CYG area dataset is intended to be used as a guide only. We do not verify that they are accurate or complete.
We do not accept any responsibility for any claims, loss or damage of any kind arising out of any person’s reliance on any information that either:
- is contained in or omitted from the CYG area dataset
- arises out of the inclusion or exclusion of any land, location, site or property in a CYG area.
Reviewed 3 December 2024