As part of its commitment to sustainability and environmental leadership, Dairy Management Inc. has decided to commission and conduct a life cycle assessment (LCA) of the dairy fluid milk supply chain. An initial carbon footprint study is presently being carried out with the University of Arkansas Applied Sustainability Center, focusing exclusively on greenhouse gas (GHG) emissions and impacts.
The study proposed in the present offer complements this initial study by carrying out a full Life Cycle Assessment, covering a wide range of other environmental impact categories. In parallel, it will also carry out a Life Cycle Costing focused on evaluating the potential costs or cost savings associated with different potential measures to reduce environmental impacts.
Project goal and scope
Building upon the carbon footprint study, the "beyond carbon” LCA study of fluid milk aims to carry out a full LCA of fluid milk, also screening the associated Life Cycle Costing. This comprehensive study should set the basis for ISO compatible LCA studies in the dairy field, with a focus on the assessment of impacts directly related to dairy production. The study will especially focus on:
- The environmental impacts of water consumption at all stages of the life cycle and the implications as a function of regional water scarcity.
- The impacts of dairy milk production on human health and ecosystems, accounting for the latest developments in Life Cycle Toxicity Assessment, including eutrophication, an impact category of major relevance in agricultural production.
- The impacts associated with land use, assessing the role of dairy livestock on potential changes in land use, possibly differentiating between US and other regions.
- The modelling of Life Cycle Costs in parallel to Life Cycle Impacts, with a focus on the costs and costs savings of potential actions to reduce environmental emissions.
Functional unit and system boundaries
The functional unit will be one gallon of milk consumed by a US consumer. For the agricultural production of the life cycle, separate scenarios will be carried out for 2% fat milk and whole milk, accounting for the fat-corrected-milk approach to ensure consistency with the previous work on the carbon footprint; the rest of the life cycle (transportation, retail, refrigeration) will be related to the volume of milk
The production system encompasses the following activities performed in support of milk production and delivery: raw material extraction; energy extraction, precombustion and combustion; fertilizer and pesticide production; agricultural operations and direct field emissions; delivery, distribution and refrigeration; and product loss through the supply chain. We also plan to include an initial assessment of ingested residues in milk such as pesticides, antibiotics or cleaning agents.
According to ISO, a 1% cut-off rule based on mass, energy and overall impacts in each impact category will be applied either at midpoint or at damage level. This will be supported by sensitivity studies or expert judgment to determine any additional processes that may have been neglected. Available data below the 1% cut-off will be kept in the system unless they bring obvious biases or inconsistencies.
Allocation will be performed according to the ISO hierarchy. Allocation rules selected in the carbon footprint study will be considered in priority. Additional options will be considered and a sensitivity study will be carried out on the main option to determine the implications of allocation choices on impact results.