Planning-Compliant Soil Testing & Management Plans for Coastal Developments

Confluence Environmental delivers fast, reliable Acid Sulfate Soil (ASS) assessments and management plans for developments across Sydney, Wollongong, and the Illawarra region. If you're excavating near waterways, wetlands, estuaries, or reclaimed coastal land, a compliant ASS report may be required for your Development Application (DA) or construction approval.

We provide clear, council-ready documentation to keep your project moving forward—without risk or delays.

Do You Need an Acid Sulfate Soil Assessment in Sydney or Illawarra?

Under the NSW Planning System, any site identified as Class 1 to 5 in Acid Sulfate Soil Planning Maps may trigger the need for:

• A desktop risk screening

• Field-based soil sampling and lab analysis

• A site-specific Acid Sulfate Soil Management Plan (ASSMP)

You will likely require an ASS assessment if you’re:

• Excavating more than 1 metre below the surface

• Constructing footings, basements, or in-ground services

• Drilling or trenching in low-lying or coastal areas

• Undertaking waterfront or wetland developments

• Installing bores, tanks, or dewatering systems

Our ASS Services Across Sydney & the Illawarra

We provide end-to-end assessment, reporting, and site advice:

Desktop Risk Screening

• Review of ASS Planning Maps, elevation (AHD), and land use history

• Risk profiling against triggers for excavation or drainage

Field Sampling & Testing

• In-situ soil sampling across depths

• pH and pH-KCl field screening

• Chromium Suite testing: TAA, SCr, ANC, Net Acidity

Acid Sulfate Soil Management Plans (ASSMPs)

• Detailed strategies for excavation and soil handling

• Controls for oxidation, neutralisation (lime dosing), and dewatering

• Aligned with NSW Acid Sulfate Soil Manual (2014)

Council & EPA-Ready Reporting

• Tailored to the requirements of:

  • City of Sydney, Bayside, Northern Beaches, Sutherland Shire

  • Wollongong City Council, Shellharbour, Kiama

• Clear, professional documentation accepted for DA approvals

Why Acid Sulfate Soils Are a Key Risk in Sydney & the Illawarra

From Botany Bay and Sydney Olympic Park to Wollongong Harbour and Shell Cove, acid sulfate soils are common in estuarine and reclaimed areas. When disturbed, these soils can release sulfuric acid, threatening:

• Concrete foundations, steel structures, and infrastructure

• Local groundwater and aquatic ecosystems

• Regulatory compliance and project schedules

Confluence Environmental helps developers manage this risk early—before costly delays arise.

Our 5-Step ASS Assessment Process

1. Map Review & Desktop Risk Check

2. Soil Sampling & Field pH Screening

3. Chromium Suite Laboratory Analysis

4. ASSMP Preparation with Council-Compliant Controls

5. Validation Sampling & Compliance Reporting

Typical Projects We Support

• Civil developments along the Georges River, Parramatta River, and Cooks River

• Residential subdivisions in flood-prone areas like Albion Park, Shellharbour, and Sutherland

• Industrial & infrastructure upgrades near Port Kembla, Botany, and Sydney’s western bays

• Council works involving stormwater drainage, landscaping, or dredging

Why Choose Confluence Environmental

• Based in NSW, with deep knowledge of Sydney & Illawarra’s coastal geology

• Field and lab experts in Chromium Suite analysis and pH protocols

• Proven track record of council-accepted reports and management plans

• Trusted by town planners, civil contractors, surveyors, and developers

Areas We Service

• Sydney Metro: Botany Bay, Bayside, Northern Beaches, Inner West, Canterbury-Bankstown, Sutherland Shire

• Illawarra Region: Wollongong, Shellharbour, Kiama, Albion Park, Warrawong, Port Kembla

• All coastal and estuarine areas with mapped ASS risk