The Victorian Government’s CarbonNet project conducted a 3D marine seismic survey (MSS) off Ninety Mile Beach in February 2018 evaluating the offshore formation for future carbon storage potential. Although project managers gave assurances the community remained suspicious and had significant concerns about the survey given the survey proximity to the shore, dunes and residential houses. This venture is currently connected with the Latrobe Valley’s Coal to Hydrogen pilot project.
The MSS area was located between 1 and 13 km from shoreline off the Golden Beach township midway along the Ninety Mile Beach between Loch Sport and Seaspray in south Gippsland. The MSS area covered approximately 166 km2, in water depths ranging from 15 m to 40 m.
CarbonNet says a comprehensive Environmental Plan was prepared yet not one scientist, engineer from RPS Group who conducted the survey, interested stakeholders (including Wellington Council), state government department/agency thought the proximity of the seismic booms was too close to the shoreline and may impact the dune stability due to the ‘fragile coastal dune system.’
Interestingly, some residents voiced concerns prior to survey making connections with the buyback of coastal lots along the Ninety Mile Beach noting dune stability.
And they were right to be concerned as the MSS sound pulses unearthed some significant geotechnical concerns causing enough ground movement in and around the outer dune barrier system to trigger property damage, affect people’s health and change a coastal bore chemistry to become more saline.
On February 13, residents complained on radio,
Coby Jones said the noise started yesterday, long before daylight.
“At 3am it was like bombs going off outside in the ocean. Really loud, there was a bit of a rumble right through the ground.
“It woke up my three kids, the dog’s barking, and it hasn’t stopped.
Peter Kailaris, also contacted us yesterday, saying: “It woke us up at about 3 or 4 o’clock in the morning and it just kept going every 20 seconds.”
“It was like a booming sound going through.
“It was vibrating the house.
“The dog was barking off his head. Obviously dogs are more sensitive and it’s like ringing in their ears.”
Gipplands Times newspaper noted on February 15,
Independent vibration monitoring undertaken this week on Monday and Tuesday showed low levels of background vibration before, during and after the seismic testing.
The project team argued the sound levels were well below regulatory limits and lower than typical vibrations from a passing truck, suggesting residents with queries should phone 1800 500 790, at any time of the day or night.
Despite these assurances, social media claims from a number of beachside residents, ranging from Loch Sport to Golden Beach, have detailed being awakened by loud booms in the early hours of the morning, houses shaking, dogs barking, and claims of nausea caused by sound waves.
CarbonNet director spoke on ABC Gippsland Radio the same day stating the vibration produced, ‘less than typical traffic noise and road vibration.’
Since when does traffic noise cause property damage. Same spokesperson also stated the onshore issues were ‘consistent with our expectations when we were planning the survey.’
So where was that information in the Environmental Plan and who, from the community, was informed of these expectations? This issue is addressed in Legal liability and risks page
Likewise, it was agreed with the community they would not operate on weekends. Unfortunately that didn’t happen. The consequences from the MSS remains ongoing.
The question now is – has the dune system been negatively impacted or suffered permanent damage from the intense vibration? The community remain vigilant while we wait for an audit report.
If this project becomes commercial, new pipeline infrastructure will need to be in place creating a degree of excavation through the dune system which would occur on the existing easements, either to the east of Golden Beach and managed by ESSO or to the west of Golden Beach managed by Gippsland Water.
Future concerns, and unknown as to the severity, is the ongoing subsidence due to overdrawing of groundwater with offshore extraction of oil and gas and dewatering of open pit coal mines in Latrobe Valley. This has the potential to result in lowering of the land surface above the aquifer, particularly at Seaspray. Then there is the every present risk of earthquakes. Story pending
HAZARD ASSESSMENT OVERVIEW OF OUTER DUNE BARRIER IN THE GOLDEN BEACH AREA
The 2014 Summary Report Gippsland Lakes/90 Mile Beach Local Coastal Hazard Assessment Project gives a better understanding of the outer dune barrier related to;
- Coastal erosion and accretion – the retreat or advancement of the coastal shore
- Inundation – flooding of areas due to river inflows or sea storms
- Aeolian (wind) transport of sediments – the formation or erosion of sand dunes
Shoreline erosion is very real with a recent tidal surge causing mild erosion along the Ninety Mile Beach
This document is comprehensive for what can be predicted but many uncertainties still exist. The report notes seven principal forcing factors identified as influencing shoreline erosion susceptibility and hazard, covering physical, environmental and biological factors:
- Fabric – represents the geology and underlying material of the shore
- Form – the physical shape of the shoreline
- Structures – artificial shoreline structures such as breakwaters, sea walls or groynes
- Wave conditions – the height and frequency of waves meeting the shoreline
- Currents – represents the speed of flow beside the shoreline
- Coastal vegetation – describes the type of shoreline vegetation types
- Land use – represents different risks due to residential or farm use for example
Two factor most significant and advantageous for Golden Beach are existing volume and height of dune barrier itself so the Golden Beach area is not considered a high hazard risk of shoreline erosion and over-wash.
Source – Report 1: Summary Report Gippsland Lakes/90 Mile Beach Local Coastal Hazard Assessment Project
Vegetation and salinity also continue to play an important part for stability of the dune system all along Ninety Mile Beach from Seaspray to Lakes Entrance as this dune barrier protects the Gippsland Lakes RAMSAR site from sea‐based impacts. This RAMSAR area contains 540 flora species and 300 species of indigenous fauna and migratory bird species listed under the Japan‐Australia Migratory Bird Agreement (JAMBA) and China‐Australia Migratory Bird Agreement (CAMBA) (Parks Victoria, 2003).
Our committee continue to seek information to further our knowledge on the dune system to ensure all project development is appropriate.