Attachment H - Acid Sulfate Soils Assessment

                             PROPOSED COMERCIAL & RESIDENTIAL DEVELOPMENT
                             30 & 32 DOONELLA STREET, TEWANTIN

8.0      APPLICATION TO LOCAL COUNCIL REGULATION
Development involving ASS must comply with the requirements of State and Local government regulations
pertaining to ASS. Locally, NC has developed the ASS Overlay Code, and its attendant guidelines, as part
of the Noosa Plan 2020.
The purpose of the ASS overlay code is to ensure that the generation or release of acid and metal
contaminants from disturbance of ASS does not have adverse effects on the natural environment, built
environment, infrastructure or human health.
This is achieved through compliance with the following development outcomes:
    a) development ensures that the release of acid and associated metal contaminants into the
       environment is avoided by either:
           i.    not disturbing ASS when excavating or otherwise removing soil or sediment, extracting
                 groundwater or filling land; or
           ii.   treating and, if required, undertaking ongoing management of any disturbed ASS and
                 associated drainage waters.
Based on our review of the geotechnical investigation results, regional geology, published ASS risk mapping
and proposed development details, it is recognised that the proposed works will not involve disturbance of
soil or groundwater conditions which are likely to contain ASS.
Proposed site development will not generally involve disturbance of soil below an elevation of RL 5 m AHD,
and where excavation below RL 5 m AHD is required, such works would be expected to disturb only residual
(non-ASS) soil of a relatively small total volume (~60 m3), which would present a negligible risk of ASS
disturbance.
Based on the limited extent of excavation below RL 5 m AHD, and presence of residual subsoils from a non-
ASS geological unit, the proposed development is deemed to conform with performance outcome PO1 of
NC’s ASS Overlay Code (i.e. development does not disturb ASS).


9.0      RECOMMENDATIONS
Proposed site development would have a negligible risk of encountering ASS or affecting groundwater
conditions which may impact ASS prone areas. The proposed development may therefore proceed without
need for any further specific ASS management measures. No further site assessment regarding ASS is
warranted for the proposed development.
Should site conditions be encountered during operational works which vary from those described herein,
Tectonic or another suitably qualified ASS specialist should be contacted immediately to inspect the site
conditions, assess the potential ASS risk and provide recommendations as to how works may safely
proceed.


10.0 LIMITATIONS
Your attention is drawn to the document Limitations, which is attached at the end of this report. The
statements presented in this document are intended to advise you of what your realistic expectations of this
report should be, and to present you with recommendations on how to minimise the risks associated with the
services provided by Tectonic for this project.




26 May 2021
Report No. 18151-002-Rev0                             6