Underground Petroleum Storage Systems

We assess, supervise, and validate the removal of Underground Petroleum Storage Systems (UPSS) in line with NSW EPA requirements — helping clients manage risk, support approvals, and avoid costly delays.

Why UPSS Must Be Assessed and Removed

UPSS (also known as underground fuel tanks) are commonly found at:

  • Former service stations or depots

  • Industrial or agricultural properties

  • Commercial buildings (e.g. with backup generators or waste oil tanks)

  • Council depots and government facilities

Even disused tanks can leak over time, leading to petroleum hydrocarbon contamination in soil or groundwater. That’s why the NSW Protection of the Environment Operations (Underground Petroleum Storage Systems) Regulation 2019 requires proper decommissioning, assessment, and validation.

Our UPSS Services – End-to-End Environmental Support

We provide a complete service for managing UPSS sites, including:

1. UPSS Site Assessment

  • Desktop review of historical use and tank location

  • Preliminary Site Investigation (PSI) or Detailed Site Investigation (DSI), as required

  • Soil and groundwater sampling to screen for TPH, BTEX, PAHs, and leaking tank indicators

  • Vapour risk screening (if relevant to nearby buildings)

We determine whether contamination is present and how to manage it in line with the NSW UPSS Regulation and NEPM (ASC) 2013.

2. Tank Removal Supervision

We provide environmental oversight during the removal or decommissioning of tanks, including:

  • Engagement of licensed contractors (if required)

  • On-site supervision of excavation, tank extraction, and waste management

  • Contingency planning for unexpected conditions

  • Immediate response to free product, odour, or visible contamination

  • Collection of field screening data and confirmatory samples

We ensure the removal process is safe, compliant, and well-documented.

3. Validation Sampling & Reporting

After tank removal, we complete validation to confirm the site meets regulatory requirements:

  • Soil and groundwater testing via NATA-accredited laboratories

  • Field documentation including tank removal photos, soil conditions, and waste tracking

  • Comparison of results to EPA and NEPM guidelines

  • Preparation of a Validation Report suitable for submission to council, the EPA, or a site auditor

We can also assist with follow-up remediation, if contamination is detected.

Who We Work With

We support:

  • Property developers preparing sites for construction or subdivision

  • Builders and civil contractors who uncover tanks during earthworks

  • Real estate professionals and asset owners managing divestment or redevelopment

  • Councils and public works managers

  • Environmental consultants seeking UPSS support on broader contamination jobs

Why Choose Confluence Environmental?

  • End-to-end UPSS support – from initial assessment through to sign-off

  • Experienced in fuel, hydrocarbon, and petroleum risk management

  • Reports suitable for DA, EPA, or audit clearance

  • Responsive service with fixed-fee quotes

  • Trusted by developers, councils, and infrastructure clients across NSW

We help you manage UPSS issues with confidence — and without project delays.

Where We Work

We assess and manage UPSS sites throughout:

  • Greater Sydney

  • Central Coast

  • Newcastle & Lake Macquarie

  • Hunter Valley

  • South Coast, Mid-North Coast, and regional NSW

Need expert advice?

Have a disused fuel tank on your site? Need to confirm if contamination is present — or get a clearance report for council?

Call 0493 042 642 or drop us an enquiry below to speak with a UPSS consultant today.

A Newcastle NSW service station, a typical site that contains numerous underground petroleum storage systems

Frequently Asked Questions (FAQ) – Underground Petroleum Storage Systems (UPSS)

Q: What is a UPSS?

A Underground Petroleum Storage System (UPSS) refers to any underground tank and associated pipework used to store petroleum products such as petrol, diesel, oil, or waste fuels. UPSS are common at service stations, depots, industrial sites, and government facilities.

Q: Why do disused UPSS need to be removed or assessed?

Over time, old or abandoned tanks can leak petroleum hydrocarbons into soil and groundwater, creating serious environmental risks. NSW law requires UPSS to be:

  • Properly decommissioned

  • Assessed for soil and groundwater contamination

  • Validated to ensure the site is safe for future use

This is mandated under the NSW Protection of the Environment Operations (Underground Petroleum Storage Systems) Regulation 2019.

Q: When is a UPSS investigation or removal required?

You may need a UPSS assessment or removal when:

  • A tank is no longer in use or has been abandoned

  • A property is being redeveloped (e.g. for residential or commercial use)

  • A DA or council requirement triggers the need for validation

  • Tanks are discovered during demolition or earthworks

  • You’re preparing for remediation or environmental clearance

Q: What’s involved in removing a UPSS?

The typical removal process includes:

  1. Site inspection and historical review

  2. Engagement of a licensed tank removal contractor

  3. On-site supervision by an environmental consultant

  4. Safe excavation, tank cleaning, and disposal

  5. Collection of soil and groundwater samples for validation

  6. Preparation of a regulator-ready validation report

Q: How is contamination tested after a tank is removed?

Validation involves:

  • Soil and groundwater sampling at and around the tank location

  • Laboratory testing for contaminants such as Total Petroleum Hydrocarbons (TPH), BTEX, PAHs, and metals

  • Comparing results to NSW EPA and NEPM (ASC 2013) guidelines

  • Identifying whether further remediation is needed or the site is suitable for use

All testing is conducted through NATA-accredited laboratories.

Q: Who needs to review or approve the UPSS validation report?

The validation report is typically submitted to:

  • Local council, as part of the Development Application (DA) process

  • The NSW EPA, in the case of known contamination or regulated sites

  • An accredited Site Auditor, for independent sign-off (if required)

We tailor each report to meet the requirements of the relevant authority.