Traffic & Noise Assessments
Noise & Vibration Impact Assessment
Overview
The noise and vibration impact assessment (NVIA) only spans the effects for the Main Works project proposal. However, it spans all aspects of the proposal, from before until after construction. The NVIA follows guidelines, policies and industry requirements according to the NSW Department of Environment Climate Change (DECC) 2009, NSW Environmental Protection Authority (EPA) 2017, NSW Department of Environment Climate Change and Water (DECCW) 2011, Australian and New Zealand Environmental Council 1990, Department of Environment and Conservation (DEC) NSW 2006, German Standard DIN 4150 Part 2 1974 and Australian Standard AS 2187.2 2006. The effects of traffic noise impacts were assessed in accordance with the NSW Road Noise Policy (EPA 2011).
This document concludes that there will be no vibration impacts and little noise impacts from the Main Works project. Noise impacts would be ones that surpass acceptable noise management levels (NMLs). For vibration assessments, only 5 assessment locations with heritage significance fall within the required safe working distances presented in this report. Mitigation measures have been put in place for this. As well, from the predicted road traffic the impacts of noise and vibration are predicted to satisfy requirements.
Mitigation
If initial testings identify exceedings to NMLs then mitigation measures will be put in place. These include:
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identifying reasonable and feasible mitigation measures to reduce construction noise levels
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restrict access to Rock Forest site to ICNG (Interim Construction Noise Guidelines, DECC 2009) standard hours where feasible
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negotiated agreement with impacted homeowners (to be discussed in the critique)
The five locations with heritage significance are Washington Hotel, Pise ruin, a stone furnace, a pine tree, and a cemetery. The mitigation measures for vibrations are limiting the size of plant and equipment for excavation, compaction, or removal of rock and/or re-assessing the significance/sensitivity of these 5 items to vibration prior to the beginning of construction in the area.
Critique
Noise levels are said to be predicted to satisfy ICNG noise management levels at all sites but one. The one site is a residential dwelling in a rural property and exceeds 11-14 decibels of the noise management levels (see images below). Mitigation has not yet been planned for this residence but the proponent has promised to “discuss options for mitigating impacts” with the rural home dwellers. The agreement between the local homeowners and the proponent might include receiver mitigation, relocation, or compensation. This home will also experience noise levels 6 dB above NMLs at nighttime.
Blasting will occur in the early stages at night time, meanwhile, the ANZEC blasting guidelines recommend to do so in the day time to avoid impacts “during the more sensitive evening and night periods.” The assessment concludes that blast emissions are unlikely to impact nearby residences, but still a possibility. For this reason, it seems it would be better to conduct these blasts in the daytime.
As well, the assessment points out that there is little available data on the effect of noise and vibration on fauna, and therefore it’s assumed that suitable levels for fauna are equivalent to that of humans. More data in this field of study is needed to come to that conclusion.
The mitigation measures for the vibrational assessment claimed to potentially have effects on 5 significant locations and it was recommended to re-assess the significance of the locations. Instead of finding solutions, the assessors claimed to re-evaluate if any/all of the 5 locations are actually significant, therefore needing mitigation.
The summary document also accidentally left in “[insert details]” when referring to a Minister who allegedly approved the NVIA of the Exploratory Works, which makes us question the validity of the document and/or the assessors. There are also sentences that have been written twice in a row.
Traffic and Transport Assessment
Overview
The traffic section of the EIS documents the traffic and transport assessments of the proposed works and any initiatives built to mitigate adverse impacts. The assessments were done in accordance with the Secretary’s Environmental Assessment Requirements (SEARs) for the Main Works as well as all relevant governmental assessment requirements, guidelines and policies, and was prepared in consultation with relevant government agencies.
The related projects to Snowy 2.0 that are assessed in the traffic EIS are:
− Snowy 2.0 Exploratory Works (SSI-9208) – a Snowy Hydro project with Minister’s approval;
− Snowy 2.0 Transmission Connect Project (SSI-9717) – a project proposed by TransGrid; and
− Snowy 2.0 Segment Factory (SSI-10034) – a project proposed by Snowy Hydro
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The EIS outlines the traffic impacts of the projects from both the permanent and temporary infrastructure as well as within the entire disturbance area. The key areas of construction are outlined and described to be: the Talbingo Reservoir, Lobs Hole, Marica, Plateau, Tantangara Reservoir, and the Rock Forest. The assessment defines construction through different elements such as construction sites, substations, and power connections, communications systems, water, and wastewater servicing, temporary and permanent access roads, excavated rock management, launch facilities, and accommodations for the construction workforce.
Noise pollution levels from Tantangara to Marica. When looking at the Rock Forest map, R6 is visible. This is the only residential dwelling that will be affected by the development.
Mitigation & Critique
The EIS thoroughly outlines the possible traffic effects before, during and after construction for the main works project as well as for the proposed segment factory works. Very thorough assessments were conducted using data from 2010 until 2017, from traffic counts and accidents to intersections and traffic flows. As well, the EIS describes every project that can affect traffic and transport from each of the proposed projects. The safety assessment outlined the need for external help, from Safe Systems Solutions, to do a more detailed safety review of a haulage route. All 12 of the locations were deemed to have an improbable risk frequency, a medium level of risk but a high severity. Road network effects were broken into 6 different scenarios, and explored thoroughly. Mitigation is taken into consideration in the recommendations. The mitigation measures include intersection upgrades, new intersections, reduced speed areas, road maintenance and traffic management plans.
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The EIS also considered the projected increase in background traffic up to 2022. However, with these projections and the analyses, the projects will have a few negative effects.
It’s acknowledged that there are three intersections that will operate unsatisfactorily in peak season with projected traffic increased as well as the project traffic. No mitigation measures are being put in place to deal with these projections. With the winter-peak traffic, the project will create delays at three intersections:
– Snowy Mountains Highway / Vale Street: traffic increase of about 13-30* seconds
– Monaro Highway (Snowy Mountains Highway) / Bombala Street: traffic increase of 67-117* seconds
– Monaro Highway / Polo Flat Road (north end): traffic increase of about 277-477* seconds
*lower number indicates the main works only while the higher number indicates the main works as well as proposed segment factory works
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During construction, the entire area will be closed to the public. Not only will this block certain roads, but will also restrict water-access and activities due to water safety concerns during construction. The predicted construction time is 5-6 years. The EIS seems to look past the effects of this outside the disturbance area. On a positive note, after construction is complete, most areas will be open again and the developers promise to rehabilitate the land that was used for temporary infrastructure - by revegetating and rehabilitating it.