Underground Petroleum Storage Systems (UPSS) Assessment, Removal & Validation

When Do You Need UPSS Assessment or Removal?

Underground Petroleum Storage Systems (UPSS), commonly referred to as underground fuel tanks, are a major source of soil and groundwater contamination across NSW. These systems are commonly encountered at:

• Former service stations and fuel depots

• Industrial and agricultural properties

• Commercial buildings with backup generators or waste oil tanks

• Council depots and government facilities

Even disused tanks can corrode and leak over time, releasing petroleum hydrocarbons into surrounding soil, groundwater and vapour pathways. This can delay development, reduce land value and trigger regulatory requirements.

Under the NSW Protection of the Environment Operations (Underground Petroleum Storage Systems) Regulation 2019, tanks must be properly assessed, decommissioned and validated.

If your site contains or previously contained underground fuel infrastructure, environmental assessment is typically required before redevelopment, subdivision or site clearance.

Our UPSS Services - Complete Environmental Support

We provide end-to-end environmental services for UPSS sites - from investigation through to removal, validation and regulatory clearance.

1. UPSS Site Assessment

Before removal or redevelopment, it is critical to understand whether petroleum contamination is present and whether environmental risk exists.

Our assessment services include:

• Desktop review of historical site use and fuel infrastructure

• Preliminary Site Investigation (PSI) or Detailed Site Investigation (DSI)

• Soil and groundwater testing for petroleum hydrocarbons (TPH, BTEX, PAHs)

• Identification of contamination pathways and site risk

• Vapour risk screening where relevant

We determine whether contamination is present and define the appropriate management pathway.

2. Tank Removal and Environmental Supervision

Removal of underground tanks can expose previously undetected contamination. Environmental supervision ensures risks are properly managed and regulatory requirements are met.

We provide:

• Coordination with licensed tank removal contractors

• Environmental supervision during excavation and tank extraction

• Real-time assessment of soil staining, odour and free product

• Contingency response for unexpected contamination

• Field screening and targeted validation sampling

• Oversight of contaminated soil handling and waste classification

This ensures tank removal is safe, compliant and properly documented.

3. Validation and Clearance

Following tank removal, validation confirms whether contamination remains and whether the site meets regulatory and planning requirements.

Our validation services include:

• Development of validation sampling strategy

• Soil and groundwater testing through NATA-accredited laboratories

• Documentation of tank removal and excavation conditions

• Comparison of results against NSW EPA and NEPM criteria

• Preparation of Validation Reports suitable for council, EPA or site auditor review

Where contamination is identified, we can prepare a Remediation Action Plan (RAP) and assist with remediation and validation.

Who We Work With

We support:

• Developers preparing sites for subdivision or redevelopment

• Builders and civil contractors encountering tanks during excavation

• Asset owners and property managers managing environmental risk

• Councils and infrastructure managers

• Environmental consultants requiring specialist UPSS support

Why Choose Confluence Environmental

• End-to-end UPSS support - investigation through to clearance

• Strong experience managing petroleum hydrocarbon contamination

• Regulator-aligned, risk-based approach

• Reports suitable for DA, EPA and site auditor requirements

• Practical, responsive service focused on keeping projects moving

Need UPSS Assessment or Tank Removal?

If your site contains or previously contained underground fuel infrastructure, early environmental assessment can prevent delays, reduce risk and support development approvals.

We can confirm requirements and provide clear, regulator-ready environmental documentation tailored to your project.

Where We Operate

We assess and manage UPSS sites across:

• Greater Sydney

• Central Coast

• Newcastle & Lake Macquarie

• Hunter Valley

• South Coast, Mid-North Coast and regional NSW