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Noise and reporting standards – ONO comments

featured image credit: Ocean Care


We thank you for allowing us the opportunity to comment on the prescribed general requirements for undertaking initial site sensitivity verification and for protocols for the assessment and minimum reporting requirements of environmental impacts for environmental themes for activities requiring environmental authorization. 

It is of great concern for us that neither existing legislation, nor these proposed procedures, address the most urgent need to reintroduce the protective legislation that was repealed during the establishment of The One Environmental System in 2014.


  1. The Department of Environment, Forestry and Fisheries (DEFF) has a duty of care to take climate action (National Environmental Management Act 107 of 1998 section 2(4)(e)) into consideration. Urgent protocols are needed for the assessment and reporting on greenhouse gas emissions for each application. Not only direct emissions from owned or controlled sources and indirect emissions from the generation of purchased energy during the proposed application, but also extracted resource life cycle emissions associated with their production. In addition their use must be identified and quantified by the rights holder. Specific assessment protocols need to be established for reporting on full projected, latent and possible ’cradle to grave’ emissions produced, including emissions from raw materials, manufacture, transport, storage, sale, use and disposal. 
  2. A major deficiency is, and has been, the failure of consultants to consider ethnodiversity in the production of reports. It is particularly important that all stakeholders are provided with complete relevant information to allow for informed and impartial decision-making. Many of the Interested and Affected Parties (I&AP) do not speak English with the proficiency required to fully understand the literature to grasp the implications of the project and how to address these. Meaningful public participation must account for the language barriers of South Africa’s multilingual society and provide clear, comprehensive and accessible information.
  3. As reported in the Green paper published in October 2012, an Ocean Act was proposed to establish an ecosystem based management approach defining linkages to existing legislation and providing mechanisms to be followed for integrated spatial planning. An Ocean Act can provide further legal protection to the environment in which the resources are under severe pressure and threat. The Ocean Act can also provide clarity on the ecosystems’ sustainability and the rights of the associated marine fauna. 



3(b) Protocol for the assessment and reporting on aquatic biodiversity.

The term ‘aquatic’ needs some definition. As much as ‘aquatic’ means relating to water, in biological terms it means relating specifically to fresh water. This leaves the protocol open to interpretation, potentially excluding marine biota and environments, in which case the bias would be solved by the inclusion either of 3(c) Protocol for the assessment and reporting on marine biodiversity, or 3(b) Protocol for the assessment and reporting on aquatic and marine biodiversity.


3 (b) (Aquatic/ Marine)

Below you’ll find our main areas of concern, which include, but are not limited to, creating progressive mitigation for the sonic barrage of seismic testing during offshore oil and gas development, and the pollution and high risk of spills in deep water by oil and gas exploration, extraction and decommissioning.  

Our primary concern is that there is clear systemic, environmental and social injustice and fundamental flaws in the reporting process and we say this for the following reasons:

  1. The approving authority for oil and gas environmental authorization applications sits with the Department of Mineral Resources and Energy (DMRE) instead of the Department of Environment, Forestry and Fisheries (DEFF) as prescribed by the Constitution. Environmental authorities are more appropriately placed to consider, issue and ensure compliance with environmental authorisations for mining activities than the DMRE (CERet al. 2013). This requires review to ensure that the relevant government department’s constitutionally prescribed mandates are not undermined in the interests of expedience or profit by DMRE’s obligations to promote mining, at the cost of sound environmental management.
  • Oil “reconnaissance“ and other activities relating to mineral exploration are no longer included in the list of activities in the schedules to the Environmental Impact Assessment regulations promulgated in terms of the National Environmental Management Act 107 of 1998 (NEMA). Furthermore, since the repeal of Section 39 of the Minerals and Petroleum Resources Development Act (MPRDA), there is no legislative oversight for such proposed activities. There is accordingly a gap in South African environmental legislation regulating oil and gas exploration. The repeal of sections 38 and 39 has been challenged (National assembly Question No 217.{NW230E} Internal Question Paper No. 2 of 2018, 16 Feb 2018) to which the Minister of Environmental Affairs replied,

“Yes. An environmental authorisation should be required for seismic activities utilising sonic signal methodologies as these methodologies could impact negatively on marine species, including whales.

…..Currently reconnaissance, which includes seismic activities is not covered under the EIA regulations and a process between Petroleum Agency of South Africa (PASA), DEA and DMR to list this activity is underway.”

Obviously this listing needs to be fast-tracked considering the rush of Operation Phakisa and provision must be made soonest for oil reconnaissance and exploration as a scheduled activity in terms of the provisions of NEMA and subject to the provisions of the Environmental Impact Assessment regulations under the jurisdiction of the DEFF. This problem could be resolved by listing the following activity in the Listing Notices published under Chapter 5 of NEMA: “Any activity including the operation of that activity which requires a mining permit in terms of section 27 of The Mineral and Petroleum Resources Development Act, 2002 (Act No. 28 of 2002).” Alternatively, seismic surveying could explicitly be listed as an activity requiring environmental authorization.


No independent Strategic Environmental Assessment (SEA) has been conducted for offshore oil and gas development. Negative impacts of the offshore oil and gas sector, namely oil spills and pollution, to biodiversity are well documented and have massive health, wildlife, economic and societal consequences. It is imperative that an independent SEA is conducted for this entire sector (from reconnaissance, exploration, production (including distribution) and decommissioning), in order to inform the formulation and implementation of all government policies and programmes (especially Operation Phakisa), taking into consideration the regional ocean systems. 


The timing of oil and gas marine surveys and exploration is critical for least possible impact on seasonal breeding, feeding, spawning and migrations and should be regulated. Nowacek et al.(2013) concluded that the best way to mitigate negative impacts of seismic surveys on marine mammals is to separate them in time, space, or both. Permit award dates, availability of the survey vessels and the scheduling of 2D and 3D surveys must be planned accordingly. The proposed temporal window, location, and duration of these surveys and exploration operations should remain non-negotiable and an enforceable regulation, given the degree of threat due to the operation areas overlapping spawning and migration routes.

Due to the frequency and enormous extent of the multi-client surveys and exploration planned for Operation Phakisa within South Africa’s Exclusive Economic Zone (EEZ), strict, highly precautionary limits on the amounts of annual and concurrent survey activities should be prescribed. 

There is significant concern over timeous response to any oil spill based on the present listed mitigations given the rate of flow of the Agulhas current:

  1. The capping stack, which is supposed to “significantly reduce spill period” is shore-based, at minimum 50km away from the drill sites, and poses a logistical problem due to its tonnage and size in terms of transport to the drill site. It will take time to reach a deep-sea blowout.
    1. The recommended emergency equipment and team “who will be mobilized immediately” are based in Saldanha Bay, which on the KZN coast is 990 nautical miles and many days away (travelling at 10 knots).

Based on these delays, hundreds of kilometres of ocean could be fouled before proper response is in place. This needs urgent revision and adequate protocol established to protect public health, livelihoods and welfare as well as that of the marine and coastal environment. Both the emergency equipment and the team need to travel to be near operation sites, or the northern west and east coasts need their own emergency equipment and teams.

There is an urgent need for national guidelines regarding the planning and choices for and of dispersant use to mitigate any oil spill within our EEZ.

  •       Site Sensitivity Verification 

The detailing of the marine offshore space on the National Web based Screening Tool lacks data. Therefore, as it stands this Screening Tool cannot be used for the marine environment even though EIA’s are a requirement of NEMA. Although, it is known that the marine environment lacks data, due to sampling challenges and costs, there is data which could be placed into the Screening Tool. Various organisations, both governmental and non-governmental, have been undertaking sampling in the marine environment for many decades, all of which could be included in this Tool. 

However, it should also be noted that the marine environment has many data gaps and as a result the rating for sensitivity is, in most cases, regarded as low or insignificant. This is not due to real data, this is an assumption and these data gaps need urgent attention. 

2.2(b)   Protocol needs to be established prescribing Environmental Baseline Monitoring (EBM). Currently Environmental Assessment Practitioners (EAPS) are using best scientific data available drawn from foreign studies, affecting the validity of the impact assessments, making ‘minimising impact to acceptable levels’ guesswork at best. It leaves potential gains and/or losses at the inter- and intra-species levels; changes in species abundances; loss of habitat; loss of physical connectivity between habitats, and ecosystems and the unknown impacts on seabed features as well as undiscovered species unaccounted for. The EBM should provide current, robust, in-situ environmental and biological baseline data through sampling (i.e. the use of ROV’s, see (b) i), establish control reference sites critical to both an effective EIA development and providing feedback on the actual environmental impacts of the project and assessment of the mitigation measures in protecting the environment.

  1. Most deep sea ecosystems targeted for mining have some combination of ecological characteristics that make them particularly sensitive to anthropogenic disturbance, such as being largely pristine, highly structured, very diverse, dominated by rare species and (extremely) slow to recover. Accordingly, there is increasing concern that the direct and indirect impacts of mineral extraction in the deep sea will result in a significant loss of biological diversity. Remotely operated vehicle (ROV) surveys may represent a non-extractive alternative to assess demersal ichthyofaunal and benthic cover in relation to habitat structure (Makwela et al2016)on various substrata types around South Africa. ROV surveys, like diver-based Underwater Visual Census techniques, allow for a comprehensive inspection of the sampling area and should become mandatory for site sensitivity verification for deep sea, extractive mineral resource applications.


The Aquatic Biodiversity Impact Assessment

Sensitivity Ratings, Biodiversity Impact Assessments, Priority status of ecosystems etc. is terrestrially biased and a marine version needs to be established.

2.4.6.   Given the inherent risks of offshore oil and gas development, and how little is known about life on the sea floor, and particularly in light of recent global biodiversity assessments showing the planet is suffering unprecedented species loss that will have profound impacts on nature and humanity at large, the risks to the marine environment need to be fully assessed and understood. The question of how any development will impact on deep sea biodiversity key ecosystem regulating and supporting ecosystem services need special attention especially:

  1. provisioning services of the deep sea through: 
    1. fisheries;
    1. energy and mineral extraction;
    1. pharmaceutical prospecting; 
    1. search for industrial agents and bio-inspired materials that all derive from deep-sea biodiversity; and
    1. provision of food, refuge, habitat, and nursery grounds for species responsible for the services described above. 
  2. regulating services of the deep sea, through:
    1. carbon sequestration; 
    1. climate regulation, through the burial of carbon and mitigation of climate change and ocean acidification; 
    1. regulation services, such as carbon storage;

As CO2emissions continue to increase, deep sea climate regulation may become increasingly important to recognize in order to continue benefitting from this service, which also influences other services related to biogeochemical cycles and biological communities; 

  • production of oxygen (through the recycling of nutrients required by phytoplankton); and through
    • waste absorption and dilution.
  • Potential indirect impacts on the seabed and water column both within and outside of the directly mined area include the smothering of habitats and biota, interference with feeding activities, and the release and spread of nutrient-rich and toxin-laden water need to be accounted for.



  1. The accumulative effects needs to be prescribed and reported in a way which encompasses neighbouring and concurrent seismic and exploration applications. These reports must consider the risks associated with compounded behavioural disturbance and how chronically-present sound or the continuous, large input of contaminants due to operational discharges of produced water and drill cuttings from offshore oil and gas. The current published literature has not yet been able to validate, with confidence, or empirically verify that the effects of the discharges are only local (Bakke et al 2013). These could constitute a currently unknown threat to populations by changing behaviour and distribution regularly at critical times in their life history and in critical areas.

Accumulative effects have not properly been assessed for South African barring a single study on South Africa’s endangered African Penguin (Spheniscus demersus) which has shown that these animals avoid their preferred feeding areas during seismic surveys, feeding further from the survey vessel when in operation (Pichegru et al. 2017). With a 70% decline in their numbers since 2004 and commercial fishing changing and decreasing their fish stocks in the vicinity of their breeding colonies, these seismic surveys pose a real risk of further increasing fish scarcity thereby increasing foraging ranges with implications for individual and population fitness for the African Penguin.

  • Key findings and modelling must be projected for the full length of the proposed operation, regardless of activity.
  • Lack of consistency in time-frame application for impact assessments renders them unreliable. Environmental and social impacts are often measured only during the proposed operation, whereas the No-Go Alternative often projects impacts into the future beyond the project. This creates a complete lack of parity for any rational comparison of effects and makes the significant ratings therefore irrational and skewed. Protocols need to be established for this.
  • Any claims of reversible effects to organisms or environments must be supported using an ecologically relevant timescale.

5.     The assumption and nonchalant stance that larger/more mobile and/or migratory animals will avoid and move away from seismic surveys needs serious revision. There are vast amounts of literature that both agree and disagree with these movements, in addition, these movements may seem inconsequential over a short period of time but the jury is still out on long term effects at a population level. 


The problem of noise pollution through oil and gas development is a significant threat to biodiversity and its damaging effects to marine species and ecosystems must be recognised and addressed by:

  1. Ensuring that seismic surveys are subjected to environmental impact assessments that address synergistic and cumulative effects on marine biodiversity, 
  2. by assessing the socioeconomic effects of noise related impacts on commercial fisheries and local fishing communities,
  3. by applying the Precautionary Approach to ensure that ocean noise levels are not harmful for marine life and humans by developing effective guidelines to mitigate or eliminate intense noise producing activities especially in critical habitats including biosphere reserves, UNESCO Marine World Heritage Sites and Marine Protected Areas, and
  4. considering and adopting all measures necessary to prevent, reduce and control ocean noise pollution in the marine environment. 

Detailed protocols for these broad suggestions is contained in the comments to PART B: ENVIRONMENTAL THEMES, Noise, 4(a) Protocol for the assessment and reporting of Noise Impacts to 2. Noise Assessment, 3(b)and ask that those comments be applied to this heading: 


  1. Protocols must be established with regards to treatment of drill cuttings and operational waste for offshore oil and gas exploration and extraction. Potential drill cuttings’ offshore treatment and discharge to sea must be assessed in terms of impact on seafloor/ benthic community, water column biology and expected dispersion, and also detailed composition of these emissions and effluents regarding their toxicity, biodegradation, polynuclear aromatic hydrocarbon content and their metal content, need to be made public.
  2. A cost benefit analysis in the event of a spill and the consequences thereof on private individuals, the commercial sector and on the ecosystem itself must be provided. The significance of the economic toll a spill would have on livelihoods dependent on safe recreation at beaches, healthy habitats for wildlife, and industries such as tourism and fishing must be considered and compensation calculated.
    1. A total catch value must be assigned to the total fishing effort in the vicinity of the oil operations. This will place a measurement on the pre-spill status of the given fishing sector and related businesses, including its economic losses by disruptions, loss of earnings plus the effects of negative publicity, persisting public perceptions and potential fishing and harvest bans.
    1. Studies worldwide show that oil spills generate coastal impacts that can last many decades (Schmidt, 2010). Oil-polluted beaches, mangroves and estuarine wetlands rely chiefly on anaerobic degrada­tion, which is slow. Below just 10–15 cm in beach sand and 2–3 cm in muddier sediments, oxy­gen levels plummet, and from these anoxic layers, pockets of oil can leach toxicants for decades (Wang and Briggs 2013). In addition to costs incurred by clean-up activities, serious economic losses can be experienced by tourism-dependent businesses, industries and individuals dependent on coastal resources and therefore must be considered. 
  • An Oil Spill Contingency Plan (OSCP) for Subsea and Surface Release, detailing Oil Spill Response, Planning and Capacity, must be reported to both stakeholders and the public relevant for each exploration, extraction or decommissioning operation. This should be made public during the Draft Environmental Impact Assessment Report (DEIAR) process, and not “prior to start of drilling”, for proper stakeholder and I&AP engagement. It should also include the blowout management protocol for the project. Any deficit of technological expertise / resources / difficulty of effective co-ordination with all government or conservation agencies that have a statutory responsibility for some aspect of offshore oil and gas activities regarding incident management, should be highlighted. The delegated National Incident Commander, along with the intended lines of responsibility for inter-agency efforts, should be made available for proper stakeholder and I&AP engagement. The citizens of South Africa need assurance that incident management is fully informed and has capacity to deal with the latest technology, practices and risks associated with, and due to, the different geological and ocean environments being explored, prior to commencement of drilling. 
  • A DEIAR must report on mitigation or contingency plans in the event of a fire or explosions. The Chevron Nigeria Limited explosion of January 2012 and the Gunashli oilfield disaster of December 2015 are indicators of the dire need for proper mitigation planning.
  • Some sources state that the general intensity of the weather and storms are to increase in the future. With the oil and gas industries’ track record of pollution and proposed future wells nearly twice as deep as those of Total Brulpadda 1AX prospect rig, which has experienced extremely challenging metocean conditions particular to the very strong Agulhas current, the DEIAR must detail how the drill ships, pipelines and general infrastructure will respond to the environment in extreme weather.
  • The applicant must supply a risk assessment calculating the probability of an oil spill occurring. These assessments must be detailed, stating the exact calculated probability percentage. The estimated return period and the probability of a full-bore rupture in a given year for this assessment must be provided. The expected year of decommissioning of the well/s for this calculation must also be shown.
  • The DEIAR must clarify a Dispersant Use Plan:
    • The most appropriate dispersants must be listed. An explanation of their chemical components, toxicity, and potential for bioaccumulation, ecological impacts through the water column and on the shoreline, and their specific function must be also provided. 
    • There are many situations where the net environmental benefits of chemical dispersion are not clear. The dispersant effects to local flora and fauna must be indicated for all potential choices of dispersant in order for regulators to confidently decide on dispersant use issues.
    • The ability to provide timely and scientifically sound outcome and effects information is essential to support the regulators in their decision making role when approving the initial use of dispersants and whether to continue or cease their use during an incident. 
      • Predictive migration / movement maps of dispersants based on sound oceanographic and metrological science must be provided. 
      • Developers must provide proof of immediate availability of dispersants considering this is of primary importance in effecting recovery rates. 
  • The DEIAR must provide an Assessment of Onshore Environment and Mitigation in case of oil pollution. Buried oil contaminants can resurface as the beach erodes. Buried oil must be removed through mechanical excavation. The DEIAR needs detailed modelling of cross-shore distribution of oil contaminants relating to beach morphodynamic terminology to help optimize beach clean-up planning.

9.     If gas must be flared, an accurate determination of the volume of gas flared, its emissions quantity and concentration must be made known.

  1. The applicant must provide a report on how it will ensure well monitoring shall be carried out after production has ceased and throughout de-commissioning.
  1. More information is required with regards to well abandonment and its mitigation. It appears that industry standard is to effectively plug the well and never return. Given the minimal knowledge of recovery of an offshore well area, there should at least be monitoring on the environmental recovery of the area over a period of time, to enable and empower marine scientists who do not have access to expensive equipment to monitor these areas routinely, so as to make informed and better decisions based on an increasing pool of data.



4(a) Protocol for the assessment and reporting of Noise Impacts

Climate change, commercial fisheries, and offshore oil and gas activities are likely to pose the greatest threats to marine animals over the next several decades. Addressing the combined effects of these will be particularly difficult but essential to prevent declines beyond those that have already occurred. Marine seismic surveys produce some of the most intense man-made noises in the oceans and these surveys often operate over extensive areas for extended periods of time. Our comments here will focus primarily on the nature and magnitude of the threat of oil and gas development and the potential for effective conservation action.

The imperative of oil “reconnaissance“ and other activities relating to mineral exploration being included in the list of activities in the schedules to the Environmental Impact Assessment regulations promulgated in terms of NEMA remains of utmost importance to this environmental theme of Noise (see details inPROTOCOL REQUIREMENTS OF IDENTIFIED ENVIRONMENTAL THEME 3 (b) (Aquatic/ Marine). 2 above). Seismic surveying and bathymetric multibeam sonar acquisition should explicitly be listed as an activity requiring an EIA and environmental authorisation given the massive environmental impacts which are known to both marine mammals and other species. 

The EIA regulations specifically must trigger an EIA, not just the MRDPA, because marine scientists and pathologists are required, when quantifying the impact of any anthropogenic activity upon a bioweb, such as physical(e.g. barotrauma, survival), physiological(e.g. metabolic rate, biochemical stress indicators(e.g. alarm movement, anti-predator behaviour and responses) andbehavioural changes(e.g. temporary or permanent displacement and stress). Furthermore, understanding of the magnitude and type of response from fauna, which are critical to developing associated management or mitigation plans.

Ocean Noise Regulation is currently non-existent in both environmental legislation and in maritime legislation in South Africa. Given the drive to unlock the oceans economy, in terms of job opportunities and economic growth, regulations of Ocean Noise is a massive gap and in turn a massive threat to economic growth being successful due to sustainability and international standards and guidelines being over looked. It was noted in 2012, by Koper and Plön, that South Africa lags behind in its knowledge on the impacts of anthropogenic sounds on its marine life, and although the development of industry is often seen as a positive initiative to create job opportunities, the long-term effects of these developments on the marine environment are potentially being overlooked. 

Ocean Noise Regulation, (potentially a significant component of an Ocean Act) needs to be attached to NEMA and the Merchant Shipping Act 57 of 1951, which would detail protocols and mitigation guidelines, as well as requirements for responsible and sustainable noise levels within the EEZ.


No independent Strategic Environmental Assessment (SEA) has been conducted specific to underwater noise, or with the view to reduce, maintain, or manage noise levels, within South Africa’s oceans. This is critical considering the expansion of offshore oil and gas development, which subjects marine fauna to chronic noise exposure with potentially severe long-term consequences. Seismic Surveys, Vertical Seismic Profiling and Bathymetric multibeam sonar acquisition are anthropogenic sonic phenomena that are actively pursued for their powerful affective qualities. Negative impacts of sound pressure levels and frequency of anthropogenic hydrodynamic noise from the offshore oil and gas sector (namely reconnaissance, exploration, production (including distribution) and decommissioning) to biodiversity are widely recognized but uncertainty over variability in baseline noise levels often constrains efforts to manage these impacts. It is imperative that an independent SEA is conducted for this entire sector.

Protocol needs to be established prescribing EBM. Overview needs to be established on soundscapes of the South African marine environment relative to the various regions in terms of changing continental shelf, geology and bathymetry, vessel noise and underwater radiated anthropogenic noise sources (both intentional and unintentional). An inventory of the existing knowledge and research gaps needs to be formulated. The EBM should provide current, robust, in-situsource levels, frequency bands, modelling of environment and other characteristic data of all relevant natural and anthropogenic sources of sound in the water column. Marine biota occurrence, habitat and ambient noise in the various ecoregions and ecozones are required to be characterized. Based on the information collected, an acoustic energy budget comparison should be documented, putting the different natural and anthropogenic noise sources into perspective. Understanding how the variability of natural and anthropogenic contributors to sound in the water may elicit differences in ocean soundscapes is essential to developing strategies to manage and conserve marine ecosystems and fauna.

The EBM should also develop noise exposure parameters based on noise-induced threshold shift measurements (namely Temporary Threshold Shift (TTS; a noise-induced threshold shift that fully recovers over time) and Permanent Threshold Shift (PTS; a noise-induced threshold shift that does not fully recover over time) for South African marine fauna. For this an inventory must be created for all taxa based on recovery, or not, time after exposure to intense tones, band-limited noise, and underwater impulses with various sound pressure levels, frequencies, durations, and temporal patterns associated with various sound sources. Over the past number of decades various studies have been conducted globally to investigate noise-induced threshold shift phenomena in both marine mammals and in invertebrates. These studies have focused on measuring TTS and it is imperative that studies such as these are urgently undertaken for South African marine fauna. 

The Fisheries sector of South Africa is a major contributor to the economy (R6 billion per annum) and directly employs ~27 000 people in the commercial sector (South Africa, 2019). The effect on catch and abundance due to low-frequency sound, should be of direct interest to the fisheries sector and these measures are relatively simple to measure in situ. Lethal (physical), and sub-lethal effects including avoidance (behavioural), and reduced fitness (physiological) may all result in a reduced population within a given area, thereby reducing catch rates. Some threshold studies, which have only reported on only sound-pressure, may be of limited use for certain commercially valuable species, as not all species equally detect the pressure component of sound. Particle motion sensitivity, or to a combination of both particle motion and acoustic pressure, should be considered in noise impacts studies on fish and invertebrates, particularly those species lacking a gas-filled bladder (i.e. all elasmobranchs and marine invertebrates). Larvae and juveniles may be more susceptible to the harm of ocean noise in comparison to the adults of their species, potentially jeopardizing the sustainability of various populations (Banner 1973; Kostyuchenko 1973; Booman et al. 1996 ; Solé et al., 2017). 


4. Ocean Noise (Marine)

  1. Strict protocols are needed to establish geographical and seasonal restrictions to avoid ensonification of habitats and harming sensitive species, when sensitive marine mammals and fish species are usually engaged in susceptible activities such as breeding, calving or spawning, nursing, or migration. Seasonal restrictions on seismic surveys should be imposed in specific areas, or be included in the license conditions. It is not enough that the Petroleum Agency of South Africa, which promotes offshore oil and gas development, suggests this restriction on their website. It is imperative that it becomes legislated.
  • Cumulative acoustic limits, based on a noise budget, should be established leading to limits on the source levels that are introduced on a regional scale. These limits should be appropriately matched to the spatiotemporal scale and exposure rate of the risks to individuals and populations. 
  • Protocols for establishing a hearing threshold-based safety zone around potential application operation sites based on noise exposure parameters need to be put in place. Establishing a safety zone based on a Permanent Threshold Shift would reduce the likelihood of physiological effects resulting in killing of individuals, but it is not clear if physiological effects resulting in harm to cetaceans would be avoided. Such models, however, yield only approximate and often underestimated safety zone radii and should therefore be validated with field measurements (McQuinn and Carrier, 2005). Temporary Threshold Shift-based thresholds are likely to increase the size of the safety zone to beyond several kilometres, which would be difficult to monitor effectively using the methods traditionally employed during seismic surveys. Rather than establishing the safety zone radius solely based on a fixed distance, the safety zone radius should be, at most conservative, of either 500 meters or a radius determined using propagation models based on the best available data and science for a pre-determined acoustic threshold.
  • The speed at which the ship moves plus duty cycle and beam shape of the equipment governs the number of pulses, of a given intensity, at a point in the survey area which will be received. Likewise it governs the ability of animals to avoid the noise. These criteria need to be continually revised by on-board Marine Mammal Observers to ensure that they are up-to-date, precautionary, and take into account the masking effects and other potential lower-level sub-lethal impacts to individuals and populations.
  • Precautionary protocol needs to be established in areas of steep bathymetry close to an adjacent coastline for seismic surveys and multibeam bathymetric sonar. Ocean depth, multibeam echo sounders sweep a swath up to 7.4 times water depth and so affect a wide area. Potential impacts on marine mammals may range from physical damage, including gross damage to ears and the ‘bends’, temporary and permanent threshold shift (deafness), to perceptual (masking biologically significant noises) and behavioural impacts (temporary or permanent displacement and stress) as well as indirect effects (reduced prey availability) (Gordon et al., 1998). High intensity, low and mid-frequency sonar has been implicated in some fatal strandings (Frantiz, 1998).
  • Protocols need to be established for the enhanced effects of bathymetric multibeam sonar acquisition when operating it together with the airgun array. Furthermore, guidelines need to be established for the utilisation of Vertical Seismic Profiling during oil and gas exploration, and their mitigation. The use of airguns producing high decibels and amplitudes of sound are capable of inducing significant acoustic trauma.
  • Protocols to limit the disruption of rest are required. Perhaps one of the most overlooked aspects of anthropogenic noise impacts is the ‘disruption of rest periods’, which are important to migrating, or even generally moving, marine animals. The notion that animals can/will simply swim away from the widespread, disturbing noise is contentious since the valuable energy and attention used by animals for simply swimming away is at a high cost to the animal. McCauley (2000) clearly noted that humpback whales at rest were far more easily disturbed by airgun noise, than whales that were intently migrating; resting whales showed avoidance behaviour at greater distances and lower received levels of sound. 

The use of rest buffer temporal windows after surveys recognizes that the adverse effect of continuous noise exposure may intensify and last for a considerable time after the termination of the sound source. Surveys are operational every 10 seconds for 24 hours a day for 6 months, frequently compounded by multibeam bathymetric sonar output. Maladaptive neuroplastic changes within the central auditory pathway, symptomatic of noise exposure induced tinnitus, is not broached in any current mitigation. Animal models of tinnitus show it is a complex perceptual phenomenon affecting the quality of life of those afflicted. Mann et al(2010) claim that hearing impairment could play a significant role in some cetacean stranding events , and stranding events with causal links to seismic activity have been indicated in Humpback whales, Minke whales and beaked whales by Cucknell, Boisseau and Moscrop (2015).

  • In the past, the potential effects of the 2D and 3D surveys running concurrently have largely been brushed aside as “insignificant”, minimizing the very real risk of displacement from feeding or breeding areas which could have far reaching effects not only for whole, and vulnerable, animal populations, but also on the fishing sector and our food security. This demands a critical and more thorough review of any suspected risk. The compounding effects of multiple abiotic and biotic stressors associated when 2D and 3D surveys operate concurrently are severely understated. A multiple survey interaction must be considered to clarify whether the interaction is synergistic, additive, or antagonistic.
  • Protocols to establish impacts of stress need to be established. Stress does not present as an indicator for oil and gas development impacts. Acoustic pollution presents less visible but unceasingly pervasive disturbance to the ecosystems experiencing a seismic survey. Significant stress due to prolonged exposure to seismic and anthropogenic underwater noise has been measured in a number of species (Finneran et al., 2002; Eckert et al. 1998; McCauley et al. 2003; Rollard et al. 2012). Although such effects appear less severe than direct mortality or injury, they affect many more individuals and extend over significant periods of time. These studies indicate cumulative effects could result in metabolic maladaptation, suppressing growth, immune system function, thermoregulation and the reduction of reproductive rates, with implications for individual and population fitness. Chronic problems of this kind are a legitimate conservation concern. 
  1. Protocols should be established ensuring that project proponents establish communication for the duration of seismic or multibeam bathymetric surveys with stranding networks and conservation organisations local to the survey area to fully understand the potential effects of the survey on the greater marine environment and take further mitigatory action should stranding reports register adverse effects to unusual species or increased numbers.
  1. Guidelines need to be established for noise emissions and vibrations from offshore oil and gas drilling operations. These often include strong tonal components at low frequencies, including infra-sonic frequencies, thereby leading to potential disturbance, damage or interference to a variety of marine species. The full scale of this acoustic footprint, including impacts caused by vibration through drill string and casing vibration into the seabed. In addition, the vibration of the drill bit needs to be addressed.

2.1.   The identified marine noise specialist must be capable and equipped to undertake in situmeasurements (if they do not already exist) of the sound scape, and have the ability to interpret hearing thresholds (both TTs and PTS) of marine fauna in the proposed area.    

The nominated noise specialist must suggest mitigation and associated or relevant protocols. It is becoming more accepted on a global scale that mitigation measures are not adequate and the current mitigation measures have little or no effect on changes in mammal vocalizations and associated changes in behaviour. 

Given the limitations of an Marine Mammal Observer’s ability to detect a marine animals’ presence around a sound source, due to darkness, obstructed visibility (e.g. fog) and/or high sea, that animals may not be vocalizing, thus limiting the efficacy of Passive Acoustic Monitoring (PAM), greater effort is needed to assess the various technologies available for detecting marine animals in low-visibility conditions. Technologies that need to be explored include, active acoustic monitoring (AAM), radio detection and ranging (RADAR), light detection and ranging (LIDAR), satellite, and spectral camera systems, especially infrared (IR).

In terms of alternatives to seismic surveys, Marine Vibroseis is being touted as a quieter, less impactful alternative to loud noise from airguns, but it would need regulatory government agencies support to make it commercially available. Vibroseis has been used successfully in land-based seismic exploration for many years. Instead of a sharp onset, loud intense “shot”, Vibroseis uses the same energy but spread over a longer duration, thus eliminating the sharp rise time (sounds quickly increasing in loudness) and high peak pressure (volume or amplitude) of airguns – two characteristics of sound thought to be the most injurious to living tissues (Southall et al. 2007).

3. TABLE 1.

Requirements for the Assessment and Reporting of Noise Impacts for Activities Requiring Environmental Authorisation

1. General Information

A noise assessment is triggered by the national web based environmental screening tool. However, there are nomarine data in the tool. In the marine environment, due to the use of sound for survival by fauna and the anomalies that affect range of penetration of sound and speed of sound propagation in the medium, a noise assessment should be a minimum requirement for any phase of offshore oil and gas development.

2. Noise Assessment

2.2. Noise standards and methodologies for the marine space need to be referenced:

It is understood that there is no specific Act to date for the protection of marine animals from anthropogenic noise, however there are several government bodies as well as international and national organisations that acknowledge the impacts of anthropogenic noise to marine animals 

  1. The United Nations (UN) Convention on the Law of the Sea (UNCLOS 2008), 
  2. International conservation agreements IMO 2011, ASCOBANS 2012, ACCOBAMS 2012, AWI 2012, JNCC 2012, NOAA 2012, NRDC 2012, WDCS 2012, etc.
  3. Guidelines for the seismic survey operations and naval sonar have been established ACCOBAMS 2010, JNCC 2010 and EPBCA 2012. 
  4. In early September 2018 a resolution was proposed at the 67th International Whaling Commission (IWC) for the elimination of acoustic pollution that affects whales (of all 13 species and populations considered under the IWC). This resolution was passed by consensus with South Africa being one of the signatories.      

2.3.b.   Mapping the distance of the receiver from the proposed development that is the noise source/airgun for the marine space holds serious challenging anomalies:

  1. Seismic surveys are used for their high-power penetrative shock wave properties resulting in them being heard for thousands of kilometres away from the source if spread in a sound channel underwater. The recordings of autonomous acoustic seafloor recording systems of the US-NOAA on the central mid-Atlantic Ridge showed year-round recordings of airgun pulses with a dominance in summer from seismic surveys often taking place usually more than 3000 km away (Nieukirk et al. 2004). Low-frequency energy from seismic sounds may travel long distances through bottom sediments, re-entering the water far from the source (Richardson et al. 1995; McCauley & Hughes 2006). The localised measurement of noise source to a point of reception is a massive understatement of the potential extent of noise impacts for oil and gas development.
    1. Also the assumption that received airgun noise levels decrease with less and less impact on the exposed animals further from the noise source was overturned by Madsen et al(2006). They found high exposure levels at considerable ranges from the air-gun array and that received sound pressures and sound exposure levels may actually increase with ranges beyond 5 km range up to 12.6 km from source. They believe this high frequency acoustic by-product on marine mammals should not be dismissed lightly and that it poses the challenge of how to mitigate where animals can dive in and out of high exposure levels at considerable ranges from the air-gun array.

2.3.c.   Calculating the noise impact from the sound source for the marine environment is complex and much needs consideration: 

  1. It is well known that the peak energy pulses from individual source elements no longer align at locations close to seismic source array (in the ‘near field’) as a seismic source array is a ‘distributed’, rather than a ‘point’ source. Therefore the emitted sound pressure level close to the source array is lower than that calculated using the ‘far field’ calculation (reference, e.g. Urick 1983).
  2. McCauley, Fewtrell and Popper (2003) found that the ears of fish exposed to an operatingairgun sustained extensive damage to their sensory epithelia. The damage was regionally severe, with no evidence of repair or replacement of damaged sensory cells up to 58 days after air-gun exposure. This damage was seen at exposure levels that might occur several kilometres away from the sound source.

iii.  The danger of reflected sound off the surface of the sea needs to be taken into consideration. It is known to amplify kinetic and pressure effects and explains the anomalies of animals further away from the airguns being more affected at times.

iv.  The impacts of unilateral and indiscriminate traumatizing noise exposure beyond the boundaries of the seismic safety zone (such as decreased foraging efficiency, increased energetic demands, reduced group cohesion, compromised ability to nurse calves, reduced ability to communicate, increased risk of predation and decreased reproductive success and hampered avoidance of anthropogenic threats like entanglement and bycatch) on already depleted populations experiencing the cumulative impact of multiple stressors, need attention in the proposed impact management outcomes including up-to-date data on their degree of reversibility.

The most immediate and effective method of reducing impacts would be to minimize the number of surveys and the power of the sources employed. Encouraging companies to share the results of past and future surveys would be one mechanism for achieving this. 



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