The format of an Acid Sulfate Soil Management Plan (ASSMP) is designed to ensure adequate detail has been provided to demonstrate that the proposed management strategies will result in appropriate mitigation of potential ASS impacts.
In general, the ASSMP should detail an overview of the environmental attributes and potential on and offsite effects of the development disturbance on the soil and/or groundwater along with comprehensive details of previous ASS investigations, and mitigation and monitoring strategies.
A detailed description of the site works to be undertaken should be outlined, including detailed descriptions and diagrams of the known occurrence of ASS at the site, and proposed soil excavations. Details of the potential on-site and off-site effects of the disturbance of the soil and/or groundwater should also be outlined. Details of the timing and milestones of site works, including site personnel responsibilities and liaison with the Department of Environment Regulation (DER) should be thoroughly detailed.
A description of the management strategies proposed should be included, which is not limited to:
- The strategies for preventing the oxidation of iron sulfides, primarily avoidance, where possible.
- The soil excavation and treatment strategies, including neutralisation material and calculations.
- The details of temporary storage, re-use or disposal plans for excavated ASS.
- The containment strategies for any contaminated stormwater or acidic leachate.
- The details of dewatering effluent treatment, management and disposal, and contingency measures (where required).
- The performance criteria to be used to assess the effectiveness of the ASS management and monitoring measures.
- A comprehensive monitoring program for soils, surface water and groundwater quality, designed to enable the effectiveness of the management strategy to be assessed.
- A description of the contingency procedures to be implemented.
- An outline of reporting procedures and frequencies for meeting environmental performance objectives.
- A commitment to submit a closure report, at the conclusion of site works.
It is imperative that the management plan be reviewed and periodically updated to reflect knowledge gained during the course of operations. Changes to the management plan should be developed and implemented in consultation with relevant authorities.
For further information, please refer to the following investigation and management guidelines.
- DER 2015, Identification and investigation of acid sulfate soils and acidic landscapes, DER, Perth.
- DER 2015, Treatment and management of soils and water in acid sulfate soil landscapes, DER, Perth.
Read Part 1 of this article or for further information on Acid Sulfate Soil Assessments please contact our team.