Acid Sulfate Soils Information in Queensland Dan Brough Outline - - PowerPoint PPT Presentation

Acid Sulfate Soils Information in Queensland

Dan Brough

• ASS Soil Management Guideline v4.0
• National Guidance Material
• Online Data and Resources

Outline

• What’s new?

– New ASS Tips and case studies – New methodologies for treatment – Closure Reporting – More consistent wording, flow improvements

Soil Management Guideline

• Terminology
• AASS/PASS as a spectrum, not a binary
• Distinction between natural oxidation

processes and the effects of human disturbance

• MBOs

Chapter 1

• Rapid formation under the right conditions

Tip – MBOs

• Concrete – sulfate as well as acid

vulnerability

• Location/placement of infrastructure in the

environment

• Effects on metal pipes including bacterial

attack

Tips – ASS and infrastructure

• Not all ASS is mangrove mud!
• Effects of urbanisation, domestic

dewatering

• High-organic sediments
• Health effects

Case Study – Peat with Pyrite

• Mostly cosmetic changes
• Action criteria are the same

– Draft criteria for poorly-buffered sands

• Effect of cumulative disturbances
• Risk and treatment categories

– Management plan complexity appropriate to disturbance

Chapter 4

• Less emphasis on

specific legislation

• Vulnerable environments

– Groundwater-dependant ecosystems – Sensitive wildlife – Algal blooms

Chapter 6

• New ways to minimise disturbance

– Dewatering confinement technologies – Alternatives to open trenching – Drain/floodplain management – Compression and filling – Piles/foundation design

Chapter 7

• New Tip – Lime ain’t lime
• Verification Testing rates

– Not set in stone – adaptable to site – Principles for setting rates – Allowance for short-range variation in mixing efficiency – Mention of international standards for sampling

Chapter 8

• Example methods for verification testing

– Demonstration of sampling principles

• Alternative neutralising materials
• New Tip: Application rate calculation
• New Tip: Limitations of in situ neutralising

material

Chapter 8

• New Tip - Off-site

treatment

• Use of pug mills/soil

mixers

• Dealing with wastes

from treatment areas

• New Tip – Uses for

treated ASS

Chapter 8

• Mostly for local/state government installing

small infrastructure or doing maintenance

• Rates determined from lab data stored in

Qld Soil and Land Information System

• Inherent risk of overtreatment if used on

large volumes of soil

Small Volume Disturbances

Non-ASS Acidic Soils

• Restricted to soils in

ASS terrains

• Origin of acidity less

important than risk

– Volume and type of disturbance – Other leachates e.g. aluminium, iron

Non-ASS Acidic Soils

• Management =/= full

treatment

– Spot liming – guard layers – leachate management – monitoring

Chapters 11-12

• Medium- and long-term stockpiling rates

removed

• Closure Reports

– Documentation of what actually happened – Learning opportunity – Provides information relevant to future use – Provides reassurance to stakeholders – Informs remediation if something goes wrong

• Ideally form-based for most projects

Chapter 13

• Option for large, extensive projects only
• Residential subdivisions, canal estates,

made land

• Works where normal verification testing

methods are difficult to apply

• Confirmation of effective treatment in the

top 1.5m

– Most likely to be re-disturbed

Handover Testing

• Use of independent third parties
• Boreholes across final surface

– 0.5m bulked samples – No need for high-detail soil description

• Performance criteria designed allow for

minor exceedances but not systematic treatment failure

• Addendum to usual closure reports

Handover Testing

• Coming soon

– MBOs – ASS and Dredging – ASS, Groundwater and dewatering – Methods Manual

National Guidance Material

• The Soils Globe!

– Google Earth display of soil data – ASS (and other soil) mapping – 90,000 soil sites

• Open Data

– Data.qld.gov.au – Publically available soil data – Consistent format

Queensland Information Resources

• www.qld.gov.au/soils

– The resource for Queensland Government soil information – Links to all our resources and sources of further information

Web resources