After calculating GHG emissions and identifying major contributors (‘hot spots’) to overall emissions, a Management Plan allows a site to identify actions to reduce, minimise and/or avoid GHG emissions.

Actions proposed in a GHG Management Plan should demonstrably relate to emissions identified during GHG calculations. Actions may also relate to GHG emissions beyond the scope of ASC’s GHG calculation requirements if evidence is shown that these emissions are substantial.

For example, efforts to reduce GHG emissions from product transport can have a significant effect in some cases, particularly if air freight is used.

Actions proposed in a GHG Management Plan should be accompanied with means to track implementation and effectiveness.

Not all GHG emission reduction efforts require major changes to operations or large new infrastructure investments.

Incremental improvements to feed conversion ratios, mortality rates, and energy efficiency can also be effective ways to reduce GHG emissions.

GHG targets, relative to both live weight production and edible weight product, are provided in Appendix 9.

By calculating and reporting emissions on an annual basis, sites will be able to track their GHG performance over time and assess the effectiveness of actions taken in their GHG Management Plan.

Reporting of GHG emissions to ASC, with a consistent approach across certified sites, will also support ASC’s efforts to provide guidance back on the types of actions that are achieving significant improvements in GHG performance.

While calculation and reporting of GHG emissions requires the use of two allocation methods to promote transparency and consistency across certified sites, Certificate Holders may select either allocation method as the basis for identifying actions in their GHG Management Plan and tracking emissions over time.

For many sites, emissions may come primarily from the production and use of feed.

The GHG Management Plan may be site-specific or may be applicable across many sites or developed at a corporate level, provided that the GHG tracking and actions taken are demonstrated to be relevant to the site and to reflect identified hot spots of emissions.

Copies of current and previous versions of the GHG Management Plan.

Presence of a GHG Management Plan.

The GHG Management Plan is maintained by a designated member of staff and is regularly reviewed and updated.

Actions proposed in the GHG Management Plan reflect identified sources of GHG emissions.

The GHG Management Plan includes tracking of GHG emissions over time relative to the targets set out in Appendix 9.

Consistent and transparent measurement of GHG emissions following a life cycle assessment approach is necessary to underpin effective GHG reduction and management and to inform broader efforts to understand and reduce the GHG impact of global food systems.

This indicator ensures that all ASC certified sites undertake this important first step in contributing to efforts to combat climate change.

ASC does not require the use of any particular GHG calculation framework or tool or conformance with any particular GHG methodology or standard. However, some methodological requirements are stipulated in Appendix 9 to ensure a sufficient level of consistency, completeness and accuracy of GHG calculations.

Certificate Holders should consider the reporting format of the ASC Farm Standard GHG Data Submission Template in undertaking their calculations.

This includes the characterisation of GHG emissions in three distinct ways:

GHG profiles for feeds used, specific to the feed supplier and species or species group and updated on an annual basis, as required to be shared by the feed supplier according to Criterion 1.21 of the ASC Feed Standard and using the format of the ASC Feed Standard GHG Data Submission Template.

For marine salmonids only: GHG profiles for any supplying grow-out site(s) as required to be shared by the previous grow-out site(s).

Documentation of the source of any GHG emission factors used.

This may be documentation of calculation tools (e.g., the ASC GHG Calculator) or documentation of specific emission factors and their source if calculating emissions manually.

Documentation of the input variables used (e.g., quantity of electricity).

Inputs of energy should reflect those calculated in Indicator 2.10.1. All input variables should be supported by evidence such as invoices or feed use records if requested.

Documentation of conversion factor and, if applicable, allocation factors, used to convert GHG calculations from a live weight basis to an edible weight basis.

Documentation of power purchase agreements, if applicable, to demonstrate use of electricity from specific dedicated sources rather than the national or regional electricity grid.

Records of GHG profiles from feed suppliers and (for marine salmonids) prior grow-out sites are available.

GHG emissions are calculated in kg CO~2~e relative to live weight production and edible weight product and recorded using the ASC Farm Standard GHG Data Submission Template.

If using a tool other than the ASC GHG Calculator, documentation showing how the tool conforms to the methodological requirements outlined in Appendix 9;

This may be a signed declaration from the tool provider or highlighted elements in the tool’s user documentation.

Values input into the ASC GHG Calculator, another tool, or manual calculations are supported with evidence (e.g., fuel purchase invoices).

If undertaking calculations manually, demonstration of the calculations undertaken, including the use of GHG data from feed suppliers and (for marine salmonids) prior grow-out sites in conformance with the requirements of Appendix 9.

The scope of included activities reflects the requirements outlined in Appendix 9.

GHG emissions are not adjusted using carbon credits or offsets.

Certificate Holders are encouraged to use the ASC GHG Calculator, available at https://ghg.asc-aqua.org, to ensure compliance with regards to calculation scope, methods, data sources and reporting format. Use of this tool is voluntary; other tools, consultants, or internal procedures may be used if documentation is available to demonstrate compliance with the requirements in Appendix 9.

Recommended factors for converting GHG emissions from a live weight basis to an edible weight basis may be sourced from supplemental material of Gephart et al. (2021). Other conversion factors may be used if they reflect the actual edible yield (i.e., muscle fraction) of the animal.

A range of methodological frameworks and standards are available to guide life cycle assessments and GHG accounting. Use of any of these is optional, provided that calculations are still in compliance with the requirements of Appendix 9. Examples include:

Tracking use of energy inputs is a necessary step in calculating the GHG emissions associated with aquaculture production and products.

Energy inputs include all those sources of energy used for the purpose of production, including electricity and energy carriers such as diesel or natural gas.

To the extent possible, Certificate Holders are encouraged to calculate energy use specific to the certified site. However, in some cases, this may be difficult to do. For example, fuel purchased may be used to supply vessels servicing many sites, potentially both certified and non-certified sites or even multiple sites or companies.

In these cases, a portion of the overall input may be allocated to the certified site based on a logical allocation basis.

For example, dividing energy inputs between sites based on the relative number of vessel trips or using the site’s relative share of production among the group of sites serviced.

Energy inputs to hatcheries are not included in calculations of on-site energy use. However, in cases where the juvenile stage of the supply chain is integrated with grow-out, sites may choose to include this stage in their calculations to simplify calculations.

Documentation of energy intensity factors (e.g., MJ of energy per L of diesel) used if they are different to the default values used in the ASC Farm Standard Energy Use Data Submission Template.

Evidence to support the quantity of each energy input specified in calculations is available on request, along with any allocation of energy inputs between multiple sites if applicable.

This may be, for example, fuel purchase invoices or electricity use records.

The energy use value is calculated and reported in MJ of energy per tonne of live weight production.

Energy use of production is calculated for either (a) the most recent completed production cycle; or (b) three consecutive years of production.

Documentation is provided to support input variables and calculations.

The ASC Farm Standard Energy Use Data Submission Template is used to demonstrate results.

Certificate Holders are encouraged to use the ASC Farm Standard Energy Use Data Submission Template for calculating the energy intensity of production after energy inputs are quantified.

Additional energy intensity factors for a range of energy inputs are available from the UK Department of Energy Security and Net Zero.

Quarterly monitoring ensures the UoC can capture any seasonal or inter-annual variations in the data collected.

Measurements should be timed to coincide with, or immediately follow, annual turnover events when the waterbody is not permanently stratified (holomictic).

The UoC should calibrate equipment used to measure DO, TN, TP, SD and Chl-a according to the technical specifications of the equipment.

The UoC should conduct measurements of the parameters in-situ.

Samples may be sent for laboratory analysis, however variability with sample maintenance during transit can lead to inconsistent results. This is particularly evident with DO and Chl-a samples.

Documentation outlining the sampling plan to conduct quarterly monitoring and that is in accordance with Appendix 8 (8.8).

Quarterly monitoring data has been collected and submitted to the ASC Water Quality Calculator. Data should be submitted at least annually.

Evidence that quarterly monitoring data has been timed with annual turnover events (where applicable).

That equipment to measure DO, TN, TP, SD and Chl-a has been calibrated according to technical specifications.

The sampling methodology to conduct quarterly monitoring is in accordance with Appendix 8 (8.8).

The UoC has conducted quarterly monitoring of the water quality parameters and submitted data to the ASC Water Quality Calculator at least annually.

Evidence has been provided demonstrating the UoC has calibrated equipment to measure DO, TN, TP, SD and Chl-a in accordance with the technical specifications.

Paerl, H.W., Scott, J.T., McCarthy, M.J., Newell, S.E., Gardner, W.S., Havens, K.E., Hoffman, D.K., Wilhelm, S.W. and Wurtsbaugh, W.A., 2016. It takes two to tango: when and where dual nutrient (N & P) reductions are needed to protect lakes and downstream ecosystems. Environmental science & technology, 50(20), pp.10805-10813.

Information on the appropriate use of Secchi Disks can be found here: ‘What is a Secchi disk’, accessed November 22, 2023: <https://www.nalms.org/secchidipin/monitoring-methods/the-secchi-disk/what-is-a-secchi-disk/>

Example of a method for Chl-a measurements made using ethanol extraction followed by spectrophotometric measurement at wavelengths 665 and 750nm (using accredited methods: EPA method 445.0: Method 445.0 In Vitro Determination of Chlorophyll a and Pheophytin ain Marine and Freshwater Algae by Fluorescence, accessed November 22, 2023: https://cfpub.epa.gov/si/si_public_record_report.cfm?Lab=NERL&dirEntryId=309417

Cost effective example for measuring using in-situ Chl-a using a field spectroflurometer include the FluoroSense handheld fluorometer manufactured by Turner Designs and the YSI handheld meter with EXO1 (#599080) or EXO2 (#599201) sondes.

Hamdhani, H., Eppehimer, D.E., Walker, D. and Bogan, M.T. (2021) Performance of a Handheld Chlorophyll-a Fluorometer: Potential Use for Rapid Algae Monitoring. Water, 13, 1409: https://doi.org/10.3390/w13101409

Kuha, J., Järvinen, M., Salmi, P. and Karjalainen, J. (2020). Calibration of in situ chlorophyll fluorometers for organic matter. Restoration of Eutrophic Lakes, 847, 4377-4387: <https://doi.org/10.1007/s10750-019-04086-z>

The data collected as part of the 24-month site level monitoring survey is submitted by the UoC to the ASC Water Quality Calculator.

The water quality baseline is based on 24-months of monitoring data from the site level monitoring survey. However, the following phased approach is permitted when sites do not have sufficient data prior to the initial audit:

Harmful algal blooms (HABs) and Adverse Turnover Events (ATEs) are required to be reported as part of the baseline characterisation. The number of ATEs and HABs that have occurred can be recorded by conducting the following:

The methodology and analytical methods used to conduct site level monitoring survey are in accordance with Appendix 8 (8.8).

The sampling methodology for collecting 24-months of data for the site level monitoring survey, if this is not available at the initial audit.

The results of the site level monitoring survey, as determined by the ASC Water Quality Calculator.

The results of the 24-month baseline characterisation, as determined by the ASC Water Quality Calculator.

Records of HABs and ATEs from the last 10 years.

A water quality monitoring survey has been conducted by the UoC. Results are presented from the ASC Water Quality Calculator.

A sampling methodology has been presented for collecting 24-months of data for the site level monitoring survey, if this is not available at the initial audit.

The data collected for the site level monitoring survey followed the methodology and analytical measures outlined in Appendix 8 (8.8).

A water quality baseline has been characterised. Results are presented from the ASC Water Quality Calculator.

The results of the review by the UoC into adverse turnover events and harmful algal blooms in the waterbody.

Vollenweider, R.A., Rinaldi, A. and Montanari, G. (1992) Eutrophication, structure and dynamics of a marine coastal system: results of ten-year monitoring along the Emilia-Romagna Coast (Northwest Adriatic Sea). Marine Coastal Eutrophication, Proceedings of an International Conference, Bologna, Italy, 21–24 March 1990, Pages 63-106: <https://doi.org/10.1016/B978-0-444-89990-3.50014-6>

More information about the equations used for TSI assessment, including the relevant peer-reviewed scientific literature, is provided in Carlson, R.E. and Simpson, J. (1996) A Coordinator’s Guide to Volunteer Lake Monitoring Methods. North American Lake Management Society, 96 p.

Evidence of spatial management at a national/regional level for water quality can be used by the UoC to demonstrate that the intent of Indicator 2.6.8 has been met. To use this evidence, the following should be met:

Examples of outreach can include:

As per Appendix 8, section 8.7, a Terms of Reference (ToR) document shall be drafted and agreed upon by all members of the WQMN upon formation, which includes the following:

An agreed map of the WUM by members of the WQMN, which includes the components outlined in Appendix 8 (8.7).

The map should be updated on an annual basis where required.

Evidence of outreach efforts and responses (where applicable) to ASC Certified site and non-certified sites belong to ASC Certificate Holders if a WQMN needs to be established.

If a WQMN has been established, the UoC presents evidence that they have joined the WQMN or the UoC can demonstrate the spatial management of water quality at a national/regional level.

A ToR has been agreed upon by all members of the WQMN, which includes commitments to the WQMN requirements, as outlined in Appendix 8 (8.7.1).

A map of the WUM has been developed by the WQMN and presented by the UoC, which includes the components outlined in Appendix 8 (8.7).

Evidence of outreach efforts and responses to ASC Certified site and non-certified sites belong to ASC Certificate Holders if a WQMN needs to be established.

Auditor discretion should be used to determine if sufficient levels of outreach has been conducted, when such outreach has not been reciprocated.

Evidence that the UoC has formed/joined a WQMN, or that the UoC presents evidence that water quality is managed at a national/regional level.

A ToR has been presented, which has been agreed upon by all members of the WQMN. The ToR includes commitments to the WQMN requirements, as outlined in Appendix 8 (8.7.1).

To demonstrate competence, personnel responsible for conducting water quality analysis and defining the WUM should be able to:

The personnel responsible for conducting water quality analysis and defining the WUM have competencies to do so, for example a suitable level of education and/or experience.

Relevant training modules have been completed by the personnel responsible for conducting water quality analysis and defining the WUM.

The personnel responsible for conducting water quality analysis and defining the WUM have the necessary competencies.

Evidence has been presented that relevant training modules have been completed.

The following characteristics should be used to define the Waterbody Unit of Management (WUM):

A map of the WUM which includes the components outlined in Appendix 8 (8.6).

The results of measurements to confirm if the WUM is a HIE (if applicable).

A map of the WUM has been developed and presented by the UoC, according to the method outlined in Appendix 8 (8.6).

The UoC should initially define the boundaries of the Receiving Waterbody (RW) based on hydrological characteristics, which determines its sensitivity to nutrient enrichment.

Marine waterbodies include:

Waterbody types designated under national legislation should be used only if the following are met:

A map of the Receiving Waterbody, which outlines:

A map has been presented by the UoC which outlines the RW, and which supports the classification of the RW.

The results of the HRT calculation and flow rate/TSS measurements conducted by the UoC.

Evidence presented by the UoC, demonstrating the methods used to measure flow rate and TSS, in accordance with Appendix 8 (8.5 and 8.12).

The RW has poor connectivity to deep offshore waters, and/or;

The RW is sheltered from energetic conditions e.g., inflows, currents, exposure to onshore or monsoonal winds, and/or;

The hypolimnion is periodically or permanently poorly flushed.

If measurements of HRT or flow rates are not available, publicly accessible global databases can be used to obtain annual outflow estimates. Data sources include:

Examples of credible secondary sources for flow rates include government flow monitoring and modelling, as well as publicly available databases, including:

Guides on how to calculate cumulative distribution (NORMDIST function) and the 25^th^ percentile/quartile (QUARTILE function) for the flow rate data from secondary sources, using Microsoft Excel: