Alan Deering

ALAN DEERING QUESTION 1 Noosa Council is guided by, and not dictated by the Austroads Standards and Guidelines, also the Department of Main Roads Planning and Design Manual, so the Noosa Plan that states when sealing dirt roads they must be no less than 9 metres is a Noosa Council initiative. Does Noosa Council agree that any future sealing of dirt roads in the Noosa Shire will be to a minimum width of 9 metres? RESPONSE by Shaun Walsh, Director Infrastructure Services Noosa Council is guided by, but not strictly bound to, professional standards like:  Austroads Standards and Guidelines;  Queensland Department of Transport and Main Roads (TMR) Planning and Design Manual;  Institute of Public Works Engineering Australasia (IPWEA) “Lower Order Road Design Guidelines”. These documents provide best-practice frameworks, but local governments like Noosa Council have the autonomy to adopt higher or more tailored standards based on local priorities, environmental considerations, and community expectations. You are correct that the Noosa Plan (and associated infrastructure policies) specifies minimum carriageway and shoulder widths for various road classifications for Noosa Shire. We can vary from these specifications for a specific project requiring engineering justification to enable Council support. Notably, the IPWEA “Lower Order Road Design Guidelines” updated recently in 2024, specifies a sealed carriage width of 5.5 metres when traffic volumes are low, and provides a very good reference to inform any future detailed design for lower order unsealed roads across Noosa Shire. Council can also consider this recently updated document in any future review of the Noosa Plan and associated infrastructure policies. I also note that following various representations from the community, Council has initiated a review of Council's approach to management of unsealed roads, with broader consideration of environmental, community benefit and traffic safety matters to more fully inform future prioritisation and budget submissions for road sealing, of course subject to Council budget approval. QUESTION 2 Noosa Council employees such as Plant Operators are required to undergo a mandatory silica test every 12 months. Noosa Council recognises the workplace risks of airborne dust but totally ignores the health risks of airborne dust to ratepayers living on dirt roads. Why hasn't Noosa Council addressed the dust issue of residents living on dirt roads in Noosa Shire by at least adding dust suppressant in water trucks when annual resheeting of dirt roads? RESPONSE by Shaun Walsh, Director Infrastructure Services In terms of health risk, Council has undertaken a technical assessment of the potential health risks associated with silica dust generated from unsealed gravel roads within the Noosa Council region. It has evaluated the material composition, maintenance practices, and environmental exposure context, referencing applicable standards and research findings. Crystalline silica (SiO₂), primarily in the form of quartz, is a naturally occurring mineral found in many geological materials including sand, clay, and gravel. Respirable crystalline silica (RCS) is a known occupational hazard in industries involving cutting, crushing or drilling of silica-containing materials. However, the context of road dust from unsealed surfaces, particularly those maintained using natural gravel and recycled asphalt, differs significantly from high-risk occupational environments where RCS may be present. Noosa Council maintain their unsealed road networks using natural gravel blends and recycled asphalt pavement (RAP). These materials are selected in accordance with:  Queensland Department of Transport and Main Roads MRTS05 – Unbound Pavements; and  Austroads Guide to Pavement Technology Part 6: Unsealed Pavements. These standards ensure that materials meet performance criteria such as California Bearing Ratio (CBR), shrinkage product and grading coefficient, which indirectly influence dust generation and stability. In terms of health risk exposure:  Unsealed roads in these regions typically carry low traffic volumes (30–500 vehicles/day).  Dust exposure is intermittent, outdoor and dispersed, significantly reducing concentration compared to enclosed occupational settings.  A New Zealand Transport Agency study found that while PM₁₀ dust from unsealed roads can be present, respirable silica levels were generally low and not linked to adverse health outcomes in ambient settings.  NIOSH evaluations of dirt road maintenance found no erionite and only occasional silica exceedances, primarily in active roadwork zones, not general public exposure.  The Workplace Exposure Standard (WES) for RCS in Australia is 0.05 mg/m³ (8-hour TWA). Ambient exposure from unsealed roads is not known to exceed this threshold in SE Queensland. Based on current material usage, maintenance practices and environmental exposure conditions, there is minimal to no health risk from silica dust generated by unsealed gravel roads in the Noosa Council region. There is no confirmed evidence of harmful silica dust concentrations in these areas, and no recorded public health impacts attributable to road dust. The use of natural gravel and recycled asphalt, combined with routine grading and dust suppression, ensures compliance with engineering and environmental standards. In terms of testing its workforce, Noosa Council test the workers that are exposed to Respirable Crystalline Silica (RCS) such as concrete cutting, drilling and crushing works which is approximately 50 workers. Crews working on our unsealed roads such as grader crews and plant crews are not tested due to low risk profile. In terms of dust management for the community, Council’s current dust mitigation strategies include:  Routine grading and re-sheeting based on traffic volume and environmental conditions;  Use of impervious gravel blends (such as recycled road profiles) where possible and available to reduce water ingress and dust lift-off; and  Community education sheets recommending various practices including vegetative screening and reduce dust impacts near residences. Council has explored the use of dust suppressants as noted in the question and can advise as follows:  Dust suppression chemical treatments can be used to treat problematic areas and are commonly used in intensive industrial and mining applications;  The treatment is usually only effective for approximately 3 months and can make the road slippery when it rains as they are commonly hydrophobic and cause water to pond on the surface causing possible safety issues;  These chemicals are powerful and would need to be applied with great prudence as could have adverse environmental implications if overused particularly pertinent in environmentally sensitive areas of Noosa Shire;  The high cost of this treatment, short term benefits and the need for regular reapplication mean this treatment is cost prohibitive for application in Noosa Shire which has 200kms of unsealed roads.