Huon Submission to the EPA on Macquarie Harbour

HUON SUBMISSION TO EPA (4th May 2017)

(Addendum to Huon’s April 2017 EPA SUBMISSION)

1. Summary of Key Points

Please note: It is important that this submission is read in conjunction with Huon’s Apr 2017 and Jan 2017 Submission to the EPA to provide the full context to Huon’s position.

Huon remains very concerned about the environmental trends in Macquarie Harbour (MH) and future sustainability of production in the region.

Huon continues to believe that the Biomass Limit in MH should be at or below 10,000 tonnes.

IMAS results in Jan/Feb 2017

Results from the recently released Draft Institute of Marine and Antarctic Studies (IMAS) Report (Apr 2017) reinforce and expand on issues raised in our previous submission(s).

While there are some signs of recovery in the Tassal results in April 2017, the IMAS Report indicates that dissolved oxygen (DO) levels in bottom waters are arguably worse in Jan/Feb 2017 compared to the same time in 2016 and sediment conditions were significantly worse in Jan/Feb 2017 than the same time in 2016.

The IMAS Report also indicates that any signs of recovery could be quickly reversed if we see a repeat of the very low (zero) DO levels in bottom waters that occurred in 2016.

Put in context, the environmental conditions in the last twelve months still appear to be a continuation of a worsening trend that has been evident since 2013.

Tassal public statements

Tassal have made a number of recent public statements through the media, on the ASX website and on their own website in regard to current environmental conditions in MH and their strategy going forward.

If Tassal is allowed to grow out their 2016 YC stock on their remaining two viable leases this would require stocking at a rate of 51.5 T/Ha if they have only two of their leases available to them (following the destocking of their Franklin lease (266). A stocking rate of 51.5T/Ha is 47% higher than the originally proposed maximum stocking rate of 35 T/Ha identified in the Environmental Impact Statement (EIS) for the expansion in MH which was also a key parameter underpinning the Commonwealth government approval of the expansion. A stocking rate of 51.5 T/Ha would be over four times the EPA permitted limit for Huon and Petuna. It is important to acknowledge that both Huon and Petuna are incurring some level of non-compliance even at these lower stocking rates.

The Tassal results in April 2017 for leases 219 and 266 respectively still only represent 46% and 16% of the average abundance respectively for the two leases compared with the five IMAS sampling times prior to Oct-2016  and starting in Jan 2015. Both leases had virtually no living organisms in the sediments out to at least 500m in both directions at IMAS Jan/Feb sampling in 2017. If these results are compared with historical results for the same time, then both leases are clearly in a worse condition in 2017 than in 2016. This is an important consideration in light of potentially extremely high stocking rates.

Tassal knew in Sep 2016 (around the time they were transferring the 16 YC smolt into MH) that their Franklin Lease (266) had major environmental issues and soon after that, the EPA announced it would be reducing the biomass limit in MH based on the IMAS Oct 2016 sampling results. Soon after that Tassal was ordered to destock their Franklin lease (266). Yet Huon is not aware that Tassal has taken any action to reduce the predictably excessive biomass of their 16 YC fish.

In Huon’s view, the situation that Tassal find themselves in now with their 16 YC fish was inevitable – yet they are proposing that the EPA allow them to farm at a level deemed inappropriately high and instigate dredging as a remediation measure to maintain financial returns.

It is particularly concerning that Tassal have stated that dredging would underpin their environmental compliance in 2017.

Despite Huon’s strategy of stocking its MH leases at a much lower level than Tassal, Huon is still planning to start harvesting its 16 YC fish early (much earlier than Tassal is proposing) to ensure the best possible environmental outcomes for Huon’s leases and the Harbour generally.

Huon is of the view that Tassal should harvest their 16 YC early rather than exceed the biomass limit.

If Tassal is allowed to exceed the EPA biomass limit for any time it is putting the short and long term sustainability of other salmon companies and the MH environment at risk.

Tassal stated in their half year results that they held fish back to get them to a larger size to increase profits. Whereas Huon started harvests earlier than normal to reduce biomass at significant cost to the business.

World Heritage Area (WHA)

IMAS sampling in Jan/Feb 2017 has shown that Site E39 (approx. 450 m inside the World Heritage Area – WHA) is still devoid of living organisms and Sites 42 and 43, both  further inside the WHA, contain significantly less living organisms than in Jan 2015 and Feb 2016

Dredging

While the EPA has announced that Tassal will not be allowed to dredge in MH at this time, there is nonetheless the possibility that Tassal will continue to pursue this activity. Huon believes dredging is a high risk process and that any trial (should it be approved in future) should be undertaken at one of Tassal’s leases in the south east in a less compromised environment and more remote from other operators.

2. Introduction

This submission provides additional information with regard to environmental conditions in Macquarie Harbour (MH) and matters relevant to the impending EPA biomass determination and future regulation of salmonid production in MH. The information presented draws on information now available in the Draft IMAS Report Apr 2017 and Huon’s ongoing internal data.

It is important that this submission is read in conjunction with Huon’s Apr 2017 and Jan 2017 Submission to the EPA to provide the full context of Huon’s position.

3. Draft IMAS Report (Apr 2017)

Prior to the release of the Draft IMAS Report (Apr 2017) to the Project Steering Committee on 27th Apr 2017, Huon was advised by IMAS that the species abundance and diversity results in the sediment samples from our MH Gordon Lease (267) (Lease 2 in the IMAS results) were similar to those from the Oct 2016 survey and that there was possibly some signs that Beggiatoa mats had decreased but that more analysis was required to be certain. EPA had advised Huon that the IMAS results for Jan/Feb 2017 were showing some signs of worsening conditions at some sites in MH compared with results from sampling in Oct 2016.

At that stage Huon had not been informed of sampling results for other salmon company leases or the external monitoring sites.

The IMAS information for all leases and external monitoring sites has now been presented in the Draft Report to the Steering Committee. This has provided Huon with the latest information from the 2017 Jan/Feb IMAS sampling.

Note: The Draft IMAS Report (Apr 17) references “January 2017” sampling, but the actual survey period was from 17th Jan – 16th Feb so will be referred to as “Jan/Feb”.

There are many concerning aspects to the results presented by IMAS that reinforce and expand on issues raised in our previous submission(s).

These include:

  • The lack of recovery of the sediment in-fauna at most sites and further deterioration at certain sites despite the oxygen recharge since late 2016.
  • The extent of Beggiatoa (and Dorvilleid worms) across the harbour.
  • The more depleted state of sediments generally and lower dissolved oxygen (DO) conditions both at depth and in mid-waters compared with the same period in 2016.
  • The worsening condition of sediments within the World Heritage Area (WHA).

3.1 Lack of recovery of sediment in-fauna

IMAS surveys include a number of sampling transects associated with leases, as well as a significant number of sites more removed from leases. The original intent of the more remote sites was that they would act as control sites (ie. independent of fish farm effects). However, results have shown that it is not as clear cut as that, with fish farms likely having broader scale impacts and natural processes impacting on salmon farms. However, salmon farming must coexist in a sustainable way with those natural influences which are largely uncontrollable. In essence salmon production biomass is the only true lever that we have to ensure sustainability of the region.

Lease sampling sites are shown in blue and external sampling sites shown in red (Figure 1).

Note: Results shown in the report for lease transects are the average of two transects which run in opposite directions from the lease. Where results indicate no living organisms in the sediments for 500m, this means that there are no living organisms in the sediments for 500m in both directions from the edge of the lease.

The areas marked by squares/rectangles are the Zone area not the Lease area which is a smaller area contained within the lease. The pens are located within the Lease area. Regulatory compliance sites are located 35 m out from the edge of the Lease (not out from the edge of the Zone).

It is also important to note that transects only extend to 500m out from the leases. This does not mean that the sediment impacts stop at 500m.If there are no living organisms at the 500m then this result will continue out from the lease for an unknown distance.

Figure 1. Map showing external (red) and lease (blue) sites. There are two transects from each of the study leases (1-5) with five sites (0, 50, 100, 250 and 500m) on each transect. (Figure taken from Draft IMAS Report – Apr 2017)

3.1.1 Lease Sampling Sites (1-6)

Leases 1-4 have been sampled by IMAS on repeat occasions since January 2015. Lease 5 is a new lease site sampled by IMAS in Jan/Feb 2017 and Lease 6 is a site sampled by Aquanel for Tassal in mid-Apr 2017.

The IMAS Report (Apr 2017) states:

“Patterns in the abundance and number of species of benthic fauna in January 2017 remained largely unchanged from the October 2016 survey, with the exception of Lease 3” (ie. Tassal Lease 219) “ where there was a further decline.”

The in-fauna results for Leases 1-4 (Figures 2-5) show the significant and rapid decline of species abundance and diversity in the second half of 2016 with no significant improvement by Jan/Feb 2017 with  Lease 3 deteriorating further compared with Oct 2016.

  • Lease 1 (Tassal  Lease – 266)

Figure 2. Abundance per grab, number of species per grab and dissolved oxygen levels at different sample times and distances from the lease (Figure taken from Draft IMAS Report (Apr 2017))

Following a 99.56% decline in species abundance and a 96.02% decline in species diversity in the Oct 2016 sampling compared with the average of five previous sampling times from Jan 2015 to Jun 2016, there are still almost no living organisms out to 500m at the Jan/Feb 2017 sampling. How much further this extends out from the lease is unknown but is likely informed by sediment results from external sites adjacent to Lease 266 within the WHA (ie. E39, E42 and E43). (see section 3.3)

Lease 266 was ordered to be destocked by EPA in Nov 2016 by the end of Feb 2017, however harvesting of the fish off the lease did not start until early Jan 2017 and destocking was not completed until April 2017.

IMAS reported that sampling by Tassal has shown some increase in organisms within the sediments. The extent of the recovery is not presented in the IMAS report, however it would be expected that this recovery will be transient if DO conditions return to those experienced in 2016 (ie. sediments would deteriorate rapidly in the second half of 2017 as occurred in 2016) Presumably Lease 1 will continue to be destocked until a significant and sustained recovery is evident including recovery of the in-fauna to pre-2016 conditions.

  • Lease 2 (Huon Lease – 267)

Figure 3. Abundance per grab, number of species per grab and dissolved oxygen levels at different sample times and distances from the lease (Figure taken from Draft IMAS Report (Apr 2017))

Following a 80.55% decline in species abundance and a 55.93% decline in species diversity in Oct 2016 sampling compared with the average of five previous sampling times from Jan 2015 to Jun 2016 there has been no significant improvement or decline at this lease since Oct 2016.

  • Lease 3 (Tassal Lease – 219)

Figure 4. Abundance per grab, number of species per grab and dissolved oxygen levels at different sample times and distances from the lease (Figure taken from Draft IMAS Report (Apr 2017))

Following an 82.7% decline in species abundance and a 48.35% decline in species diversity in Oct 2016 compared with the average of five previous sampling times from Jan 2015 to Jun 2016 there has been a further decline in both species abundance and diversity at the Jan/Feb 2017 sampling. There were virtually no living organisms out to 500m and how much further this extends out from the lease is unknown.

  • Lease 4 (Petuna Lease – 133)

Figure 5. Abundance per grab, number of species per grab and dissolved oxygen levels at different sample times and distances from the lease (Figure taken from Draft IMAS Report (Apr 2017))

Following a 65.72% decline in species abundance and a 37.17% decline in species diversity in Oct 2016 compared with the average of previous sampling from Jan 2015 to Jun 2016, there has been no significant improvement or decline since Oct 2016.

 

Lease 5 (Petuna Lease – 215)

Figure 6. Abundance per grab, number of species per grab and dissolved oxygen levels at different sample times and distances from the lease (Figure taken from Draft IMAS Report (Apr 2017))

Lease 5 has not been included in previous IMAS lease sampling transects. Therefore, there is no direct historical comparison.

The Draft IMAS Report (Apr 2017) states:

“At lease 5, there were differences between the two transects”

“All of the sites on the deeper NW transect had markedly lower abundances and species numbers than those on the SE. Whilst this may in part be a function of the differences in depth it is known that the currents at this site tend to disperse more of the farm waste to the NW and the ecology of the species on the NW transect (diversity and abundance) is consistent with elevated levels of enrichment.”

“The sites from 0 to 100m were relatively depauperate, typical of highly enriched sediments and the dorvilleid Schistomeringos loveni was the dominant species from 100-500m.”

Therefore, despite being at the northern end of the Harbour, the NW transect is still relatively depleted.

NOTE: The Y axis scale for Lease 5 is only 0 – 120 abundance per grab compared with the figures for leases 1 to 4 where the Y axis ranges from 0 – 300 abundance per grab. The maximum abundance which was at 500m from the lease was still <20 on the NW transect.

Lease 6 (Tassal Lease – 214)

Figure 7. Abundance per grab, number of species per grab and dissolved oxygen levels at different sample times and distances from the lease (Figure taken from Draft IMAS Report (Apr 2017))

The results for Lease 6 were provided by Tassal  with sampling conducted under contract by Aquanel.

The Draft IMAS Progress Report (Apr 2017) states:

“ At Lease 6 the abundance and number of species per grab at each of the transect positions followed a typical enrichment gradient; transitioning from a relatively depauperate community typical of highly enriched sediments close to the cages to one with higher faunal abundance and species numbers with distance from the cage (ie. 250 to 500m).”

NOTE: The Y axis scale for Lease 5 is only 0 – 70 abundance per grab compared with the figures for leases 1 to 4 where the Y axis ranges from 0 – 300 abundance per grab. The maximum abundance which was at  250m and 500m from the lease was only just over 20.

3.1.2 Extent of Beggiatoa across MH

There are four leases showing thick mats of Beggiatoa at the time IMAS sampled in Jan/Feb 2017 (Fig. 8). These include the Tassal Franklin Lease (266) which was ordered to be destocked by the EPA in Nov 2016. The other 3 leases with thick mats of Beggiatoa are located in the northern end of  the harbour, including Tassal Lease (219) which is also the lease devoid of living organisms out to at least 500m plus two Petuna leases (ie. Leases 133 and 215).

The Draft IMAS Report (Apr 2017) noted that the extent of Beggiatoa has decreased since the recharge of DO in bottom waters.

However, this is a relatively superficial change at the sediment surface that doesn’t necessarily reflect deeper sediment recovery. For example, Beggiatoa was only patchy at External Site E39 yet there were virtually no living organisms within the sediments at that site. The re-emergence of Beggiatoa would be expected to occur rapidly across the harbour if DO levels in bottom waters dropped again as happened in 2016, particularly given the still relatively compromised infauna within sediments.

NOTE: the circles indicating Beggiatoa relate to severity of Beggiatoa at the sampling site not the area covered by Beggiatoa

Figure 8. Beggiatoa cover from ROV footage (Figure taken from Draft IMAS Report 2017 (pg. 19))

 

3.2 Similar or lower DO levels during IMAS sampling in Jan/Feb 2017 compared with same period in 2016

The Draft IMAS Report (Apr 2017) states:

(Page 3) – “ Dissolved oxygen conditions in the middle and bottom waters remained extremely low in late 2016 before a replenishment of oxygen was seen in the deep bottom waters at the Strahan monitoring site” (ie. Huon Lease 220) “ in early December 2016, with the effects being observed at Table Head” (ie. Petuna Lease 133) “and then at Franklin Lease” (ie. Tassal Lease 266) “primarily occurred in waters below 30m with little change observed in DO levels between 20 and 30m depth.”

“Although the observations are encouraging, and may help explain some of the benthic recovery that has been reported in benthic observations noted by the companies in March and April, it is important to recognise that a similar increase was observed in bottom water DO concentrations in early 2016 and concentrations still declined to extremely low levels six months later.”

“Given that DO levels in the middle of the water column remain low, and this mid-water region represents a much larger proportion of the total water in the harbour, there is still clearly capacity for the DO levels in bottom waters to decline.”

(Page 4) “However, it is important to keep in mind that DO levels appeared to be the major determinant of the deterioration in benthic condition witnessed in spring 2016, and while levels are currently higher, they are not dissimilar to the levels observed this time last year and mid water DO levels remain low.”

(Page 6) The Draft IMAS Report also stated that “It is also important to note that the increase in bottom water DO concentrations in late 2016 and early 2017 is not dissimilar, and arguably may in fact be lower, than that observed over the same period in the previous year” (see Figure 9).

When rainfall increases in 2017, the resulting increased outflow from the Gordon River will push the poorly oxygenated mid-water towards the bottom also with result that oceanic water is prevented from coming in over the sill at Hells Gates. Therefore, DO levels in bottom waters could decline sharply once this occurs with a subsequent flow-on impact on the viability of sediment infauna.

DO data from Huon’s MH Lease 267 (Figure 9) is consistent with the Sense-T data presented in the Draft IMAS Report – Apr 2017 (Figure 10).

A recharge in bottom water DO usually occurs over summer each year, largely because flows out of the Gordon River are low which allows well oxygenated oceanic water to come in through the Harbour entrance and track along the bottom of the harbour towards the southern end.

This increase in DO along the bottom is expected to have a rapid impact on reducing Beggiatoa, but this impact is relatively superficial on the surface of the sediments. Full recovery of in-fauna will take longer.

It is concerning that the DO recharge in bottom waters is arguably less in early 2017 than they were in 2016.

Figure 9. Daily DO readings at Huon’s MH Gordon Lease (267) (The red broken lines show the 30th Apr for each year for easy comparison)

Figure 10. Contour plots showing DO profiles through the water column from the Sense-T environmental strings at Petuna’s Table Head Lease (133 – top panel), Huon’s Strahan Lease (220 – middle panel) and Tassal’s Franklin Lease (266 – bottom panel). (Copied from Figure 2 in Draft IMAS Report – Apr 2017)

3.3 Worsening conditions in the World Heritage Area (WHA)

In addition to the information provided in Huon’s previous submission, the IMAS sampling in Jan/Feb 2017 has shown that Site E39 (approx. 450 m inside the WHA) is still devoid of living organisms and Sites 42 and 43 contain significantly less living organisms than in Jan 2015 and Feb 2016. (Figure 11)

While it is not possible to say there was a direct link between the Tassal 266 lease and the deterioration of sediment conditions at sites E39, E42 and E43, the biomass of fish on the Tassal Franklin lease continued to increase until early January 2017 when Tassal started harvesting fish off the lease.

Figure 11. Plots of total infauna abundance per grab at 23 IMAS external sampling sites in MH from surveys in Jan 2015, Feb 2016 and Jan 2017. (Extract taken from Figure 8 in Draft IMAS Report – Apr 2017)

4. Tassal media releases, ASX statements and website information

Tassal have made a number of public statements through the media, on the ASX website and on their own website recently in regard to current environmental conditions in MH and their strategy going forward.

4.1 Tassal have suggested recovery of environmental conditions in MH

4.1.1 Huon’s view

Huon agrees that there has been a recharge of dissolved oxygen in bottom waters in early 2017 associated with a decrease of Beggiatoa mats and early signs of living organisms re-colonising fouled sediments. This is encouraging because it does show the capacity of nature to rebound.

However, the DO recharge in bottom waters and recovery of sediments is a process that occurs every year and should not be seen as evidence of a sustained recovery. IMAS results indicate that the DO levels in bottom waters and conditions of sediments in and around salmon farms is worse in early 2017 than IMAS sampling results at the same time in early 2016. There is also still a large volume of mid-water in the harbour with low DO.

Therefore, we are entering 2017 at a more compromised state than last year and any signs of recovery could be quickly overwhelmed if environmental conditions seen in 2016 were repeated.

On this basis, future biomass in MH must be managed cautiously otherwise we are at significant risk of seeing a continuing downward trend in environmental conditions.

4.1.2 Below are comments in relation to Tassal information

4.1.2.1 Data released on the Tassal website on 28th April 2017 showed a figure comparing the abundance of organisms/m2 at their MF Lease 219 and their MF Lease 266 comparing Oct-2016 (IMAS results) and Apr-2017 (Tassal/Aquanel results).

  • The abundance of organisms per m2 increased from approx. 145 to 450 individuals/m2 in Apr 2017 at Lease 219 and from approx. 1 to 90 individuals/m2 at Lease 266. These results still only represent 46% and 16% of the average abundance respectively for the two leases compared with the five IMAS sampling times prior to Oct-2016 and starting in Jan 2015.
  • There hasn’t been any similar sampling done at the same time in previous years so there is no direct comparison to ascertain whether this is better than sediment conditions for the same time historically.
  • The Figure fails to show that both Lease 219 and Lease 266 had virtually no living organisms in the sediments out to at least 500m in both directions at IMAS Jan/Feb sampling in 2017. If these results are compared with historical results for the same time then both leases are clearly in a worse condition in 2017 than in 2016.
  • It is expected that a return to low DO levels at depth in 2017 would quickly see this sediment recovery reversed.

The DO levels in mid-water and deeper in MH  in early 2017 are similar  (or arguably worse in bottom waters) to the same period in 2016 and sediment conditions at farm leases and many external monitoring sites generally within the harbour are significantly more compromised in IMAS sampling in Jan/Feb 2017 cf. Feb 2016.

Therefore, both the water column and sediments are already more vulnerable to poor environmental influences in 2017. Similar environmental conditions to those that occurred in 2016 will likely result in significantly more rapid, more severe and more extensive deterioration of DO and sediments.

The early signs of recovery reported recently in Tassal’s public statements may very quickly be reversed by poor environmental conditions even if sites are only stocked at the same biomass levels farmed in 2016. Production of additional biomass will only increase he risks. The End of Month Industry biomass data for MH in 2016 reported in AMA Reports (and shown in Huon’s previous submission to EPA in Mar 2017) clearly show that actual biomass in 2016 was well below 14,000 T (Figure 12). The predicted biomass being expressed by Tassal in public statements would see a substantial additional increase in pressure on the system.

Huon is uncertain as to where Tassal calculate a figure of 1% additional oxygen draw down. Additional detail on how it is calculated is needed to verify its validity.

However, Huon notes that the Cawthron Report on MH (Aug 2015) indicated that 4,000 tonnes of fish could be consuming in the order of 5 tonnes of oxygen per day (pg. 50) so it is not insignificant in terms of an additional draw down of oxygen within the system. It is not the relative percentage that is important just that it is in addition to all other oxygen use in MH.

Figure 12. Actual end of month industry biomass data in MH (Taken from MH AMA Report)

4.1.2.2 Tassal have indicated publicly that they expect to exceed the pending EPA’s sustainable biomass determination for 2017.

Tassal are predicting a peak 2017 biomass in MH of 18,000 Tonnes resulting from the grow-out of their 16 YC stock. This means that Tassal (in their own right) are expecting to have a peak biomass in MH of around 8,233 Tonnes if biomass is allocated to companies based on lease area (ie. 30.24%  of 14,000 T =  4,233 T plus an additional 4,000 T = 8,233 T).

Tassal currently only have 160 Ha out their 280 Ha available for farming due to the EPA order to destock the Franklin Lease (266) in Nov 2016. Tassal have indicated that they will grow out their 16 YC fish on leases 219 and 214.

This would mean that Tassal would have to stock leases 219 and 214 (ie. 160 Ha) at an average stocking rate across the two leases of 51.5 Tonnes/Ha. This is 47% higher than the maximum stocking rate proposed in the EIS for the expansion of farming in MH of 35 T/Ha which was also the basis for Commonwealth government approval.

To put this in context, Huon is only permitted by the EPA to stock at 12.46 T/Ha and Petuna at 9.65 T/Ha. Therefore, Tassal would be stocking at over 4 times higher than the EPA permitted stocking rate for Huon and over 5 times higher than the EPA permitted stocking rate for Petuna. Given that both Huon and Petuna lease still suffer some non-compliance at low stocking rates, allowing Tassal to farm at 51.5 T/Ha is not acceptable.

This is particularly the case given that Tassal’s 219 lease was also virtually devoid of living organisms out to at least 500m from the edge of the lease in both directions only a couple of months ago at the time of IMAS sampling in Jan/Feb 2017. It is also unacceptable to Huon because of the possible impacts this stocking rate may have on an adjacent lease (only 1 km away) might have on Huon leases given the extent of the impact extending out from the Tassal 266 lease.

Given the compromised state of DO and sediments in early 2017 and Tassal’s stocking history over the last 12 months in MH, Huon has no confidence in Tassal’s assertion on the ASX website that they will be strictly managing their biomass exceedance in a way that does not compromise the environment. Huon’s concern is exacerbated by Tassal’s statement that their “strategy for the 2016 year class is underpinned by improved waste management systems to maintain compliance” when the EPA has now announced that they will not approve the use of the system based on the risks that it poses.

Huon asks “What contingency plan does Tassal have if the DO at depth drops to effectively zero again in 2017 (as happened in 2016) over a wide-scale area of the harbour seafloor with resulting rapid and extensive deterioration of sediment?

4.1.2.3 Dealing with Tassal’s predicted breach of their expectation of the impending EPA biomass limit

Tassal’s media release on the ASX website on 27th April 2017 stated:

Tassal is proposing a transition to the new biomass limit in Macquarie Harbour as they will be 4,000 T over the EPA biomass determination. However, the EPA is yet to make its determination?

Tassal entered their 2016 year class fish into the Harbour when their biomass limit was 33.58 tonnes per hectare – which they say would have meant that they were in compliance with the limit at the time of input and forecast ongoing compliance with the limit.

Huon’s view is that Tassal’s production strategy in MH has been at odds from the start with the intended aims of the EIS for the expansion of farming in MH and the MH Area Management Agreement (MH AMA) which was that biomass would be increased gradually by all companies on an equitable basis (ie. tonnes/hectare) in response to monitoring data to allow adaptive management.

For Tassal to maintain compliance with the 33.58 tonnes per hectare biomass limit in place when they transferred their 16 YC into the Harbour, they needed to farm their leases sustainably. Following the overstocking of the Franklin Lease (266) which resulted in the EPA order to destock, Tassal now only have 160 Ha of lease area available which will mean they would need to stock this remaining 160 Ha at a peak biomass in the order of 51.5T/Ha if they were to farm their total 16 YC stock.

Tassal knew in Sep 2016 (around the time they were transferring the 16 YC smolt into MH) that their Franklin Lease (266) had major environmental issues and soon after that, the EPA would be reducing the biomass limit in MH based on the IMAS Oct sampling results. Soon after that Tassal was ordered to destock their Franklin lease (266). Yet Tassal has done nothing to reduce the predictably excessive biomass of their 16 YC fish.

The situation that Tassal find themselves in now with their 16 YC fish was inevitable – yet they are proposing that the EPA allow them to farm at a level deemed inappropriately high and instigate dredging as a remediation measure to maintain financial returns (see section 4.2).

4.1.2.4 Tassal is proposing to pull forward its current stock of fish harvesting (ie. 16 YC) to December 2017

Despite Huon’s strategy of stocking its MH leases at a much lower level than Tassal, Huon is still planning to start harvesting its 16 YC fish early (much earlier than Tassal is proposing) to ensure the best possible environmental outcomes for Huon’s leases and the Harbour generally.

In Huon’s view, Tassal should harvest their 16 YC early rather than exceed the biomass limit

If Tassal is allowed to exceed the EPA biomass limit for any time it is putting the short and long term sustainability of other salmon companies and the MH environment at risk.

Tassal stated in their half year results that they held fish back to get them to a larger size to increase profits. Whereas Huon started harvests earlier than normal to reduce biomass at significant cost.

4.2 Dredging of sediments as a remediation strategy for seabed fouling

Tassal have stated in media/ASX releases that “their strategy for the 2016 year class is underpinned by improved waste management systems to maintain compliance”.

Tassal has indicated that they “have been in regular communication with the EPA regarding a proposed trial of proven waste capture and recovery technologies. The focus of the trial will be on the safe removal of fish waste from the seabed within the marine leases. All waste will be managed to the highest standards and disposed of on land. The proposed trial has an environmental monitoring framework to monitor process, report results, identify disposal options and manage risks.”

Huon has serious concerns about the possible detrimental impact that a dredging process would have on Huon’s commercial operations and the environment in MH more generally. Particularly given that dredging is not used anywhere else in the world that Huon is aware of as an accepted process for dealing with waste under commercial salmon pens.

There are a number of risks associated with dredging, including;

  • Stirring up of sediments which subsequently sucks the DO out of the bottom waters due to bacterial activity. This has the potential to artificially stop the natural sediment recovery process and result in death of living organisms within the sediments earlier than might otherwise have occurred.

 

  • Disturbance and distribution of sediments (including toxic gases) through the water column and through other leases.

 

  • Disturbance and distribution of disease organisms into the water column and through other leases, particularly if there is active infections occurring on leases.

 

  • Disturbance and distribution of known heavy metal contamination in sediments present from the historical and still current outflow from the mines in the region via the King River.

 

The risks are escalated in MH due to the very fine nature of the sediments that easily billow up from the bottom upon disturbance. At certain times there also be what is termed “Beggiatoa streaming” where there is a cloud of Beggiatoa above the sediment surface.

The undesirability of remedial dredging is highlighted in the Summary Tables of an IMAS FRDC Project (Project No. 2010/063) undertaken in 2010 “Evaluation of approaches to improve sediment remediation (rate & function) under salmonid fish cages”

Below is the summary of scored criteria for “Dredging” as a remediation technique under salmon pens. (“Dredging” is defined as removal of contaminated sediments by suction, grab or other method)

  1. Complexity of Approach – HIGH
  2. Impact on fish health short term – HIGH
  3. Toxicity – HIGH
  4. Ecological Concerns – HIGH
  5. Water Quality Impacts short term – HIGH
  6. Waste disposal – HIGH
  7. Potential Public Concern – HIGH
  8. Overall Assessment Suitability – LOW
  9. Main Disadvantage – CAN RESULT IN SIGNIFICANT SEDIMENT DISTURBANCE AND RELEASE OF OTHER CONTAMINANTS (eg. metals)
  10. Regulator Concerns/ Issues – ECOLOGICAL EFFECTS. WATER QUALITY ISSUES. CONTAMINANT ISSUES. WASTE DISPOSAL.
  11. Farm Based Concerns/Issues – TOO MANY ISSUES WITH REGULATION
  12. Acceptability to Aquaculture Managers – LOW
  13. Acceptability to Environmental Managers/Regulatory Authorities – LOW

 

Implications of Tassal’s proposed remedial dredging on the future of the IMAS FRDC Project in MH

Tassal hasn’t raised the possibility of dredging with the IMAS MH Project Steering Committee, however it would be important to know what was happening in this regard as this could significantly affect future IMAS results for a range of reasons.

Huon’s immediate concern was that Tassal were advising that they were already moving dredging equipment into place on the water in MH in the week starting 1st May 2017 and were only assuring Huon that dredging operations would not start for the next few days.  However, as of 3rd May 2017, Huon understands from a public EPA statement that the Tassal dredging proposal won’t be allowed in the short term, but that Tassal may wish to continue pursuing this methodology through a more rigorous assessment process.

Huon do not believe dredging is the way to manage fouled sediments under pens because natural recovery of leases through fallowing is the international standard, dredging is not used commercially overseas and there are significant inherent risks with dredging, particularly in an environment like MH where the sediments are very fine, salmon farms are so close together and the close proximity to the World Heritage Area.

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