For Using the LCA Methodology Within the Sarma Project

Guidelines

for using the LCA methodology within the SARMa Project

Definition of a methodology for the Life Cycle Assessment

(LCA) of natural and recycled aggregates

Step 1: LCA of natural aggregates

Version V2

November 2009

Politecnico di Torino

DISPEA – Department of Production Systems and Business Economics

Authored by:

Gian Andrea Blengini, Ph.D.

Elena Garbarino, Ph.D.

Report issued by:

Politecnico di Torino

Department of Production Systems and Business Economics (DISPEA)

Corso Duca degli Abruzzi 24

10129 TORINO

ITALY

Scientific supervision:

Gian Andrea Blengini

Senior Researcher

e-mail:

Acknowledgements:

The authors would like to thank Cavit SpA and Unical SpA for the data and information supplied, the staff of Provincia di Torino and Professor Vanni Badino of Politecnico di Torino for the valuable co-operation.

Disclaimer:

The information reported in the present guidelines is accurate according to the best knowledge of the authors. The content of this document is to be used within the SARMa Project by the project participants in order to carry out their own LCAs relevant to natural and recycled aggregates. The European Commission accepts no responsibility or liability whatsoever with regard to the information presented in this document.

Summary

The present guidelines are to be used within the SARMa Project by the participants involved in WP 3 activity 3.3 in order to carry out their own life cycle assessments (LCAs) relevant to natural and recycled aggregates.

In the first section a LCA methodology specific to the aggregate industry is proposed. Such a common methodological framework can be adapted to different aggregate products (sand, round/crushed gravel, tout-venant, etc…), to different quarry typologies (wet/dry), different orebodies and different excavation techniques (blast/mechanical).

The methodology is a process based LCA, according to ISO 14040-44 standards, which tries to overcome some of the most important drawbacks of mining-LCAs, as identified in the international literature, with the overall objective of making the life cycle approach operational and meaningful to the aggregate industry in SEE countries.

Natural aggregates come first (step1), then the LCA methodology is extended and adapted to the production of recycled aggregates (step 2). Finally, a comprehensive methodology is proposed in order to assess the environmental performances of a real system in which natural and recycled aggregates co-exist (step 3) and where quarrying + recycling + transportation network + alternative end-of-life are balanced in order to optimise energy and environmental efficiency atsystem level and learn more about a desirable sustainable supply mix (SSM).

In the present version, methodological guidelines are limited to step 1: LCA of natural aggregates (eco-profile).

The second section of the report gives an example of LCA application based on a case study of a quarry located in Torino (Italy).

In the last part, a set of tables to be filled in by SARMa partners is provided together with recommendations on how to collect data from quarry sites. Such data will be elaborated by the LCA task group co-ordinated by Politecnico di Torino.

TABLE OF CONTENT

Summary

1. Proposed LCA methodology for the SARMa Project (step 1)

1.1 The three inter-dependent Life Cycles in the mining/quarrying industry

1.2 Implementation of the LCA methodology in SARMa

1.3 End-use of aggregates and Functional unit

1.4 System description and System boundaries

1.5 Allocation rules

1.6 Data quality, uncertainty and cut off criteria

1.7 Adopted Environmental Indicators

2. Example of LCA application to a natural aggregate quarry

2.1 Description of the quarry

2.2 Description of the quarry products

2.3 Description of the process

2.4 Inventory data

2.5 Life Cycle Impact Assessment

3. Questionnaire for data collection within SARMa case studies

3.1 Quarry development

3.2 Quarry closure

3.3 Quarry infrastructure

3.4 Aggregate production

3.5 Recultivation

References

Annex 1: Questionnaire for Quarry Unit description

Annex 2: Land Quality categories according to Eco-Indicator 99

Introduction

The present guidelines were issued by the LCA research group operating at DISPEA (Department of Production Systems and Business Economics) of Politecnico di Torino under the SARMa Project.Guidelines are to be used within the SARMa Project by the participants involved in WP 3 activity 3.3 in order to carry out their own life cycle assessments (LCAs) relevant to natural and recycled aggregates.

Objectives:

With the objective of making the life cycle approach operational and meaningful to the aggregate industry in SEE countries, a LCA methodology specific to the aggregate industry is proposed.

Such a common methodological framework can be adapted to different aggregate products (sand, round/crushed gravel, tout-venant, etc…), to different quarry typologies (wet/dry), different orebodies and different excavation techniques (blast/mechanical).

Scientific background:

The present guidelines arebased on the experience gathered by theLCA research group of Politecnico di Torino, in particular on LCAs of natural aggregates, recycled aggregates, cement, concrete, other construction materials and whole buildings.

The standard LCA methodology is not described, as it is assumed that SARMa participants have access to the ISO 14040 and 14044 standards.

However, the LCA research group of Politecnico di Torino is available to assist SARMa participants supplying them any information needed.

Only a few words on the general LCA methodology are here recalled:

“Traditional LCAs capture and describe the environmental effects associated with a product, process or activity over its whole life cycle by calculating the material and energy requirements as well as emissions to air, water and soil and by assessing the related environmental consequences.

According to ISO 14040, an LCA comprises four major stages: goal and scope definition, life cycle inventory, life cycle impact assessment and interpretation of the results (ISO, 2006).

The goal phase defines the overall objectives of the study. The scoping phase sets the boundaries of the system under study, the sources of data and the functional unit to which the achieved results refer.

The life cycle inventory (LCI) consists of an eco-balance for the process or product being studied, i.e. a detailed compilation of all the environmental inputs (material and energy) and outputs (air, water and solid emissions) at each stage of the life cycle.

The inputs and outputs are not interesting per se, but their potential environmental impacts are. Hence, the life cycle impact assessment (LCIA) phase aims at quantifying the relative importance of all environmental burdens obtained in the LCI by analysing their influence on selected environmental impact categories.

In the last step of an LCA study, the results from the LCI and LCIA stages are interpreted in order to find hot spots and compare alternative scenarios” (Shields et al., 2009).

Expected results:

Data collected by SARMa partners, according to recommendations provided, will be elaborated by the LCA task group co-ordinated by Politecnico di Torino and will be used for a LCA manual dedicated to LCA application to the aggregate industry in SEE countries.

1.Proposed LCA methodology for the SARMa Project (step 1)

The present guidelines are to be used by SARMa participants as a common methodology to integrate LCA (Life Cycle Assessment) ISO 14040-44 standards and SETAC recommendations into the aggregate industry in SEE countries.

1.1 The three inter-dependent Life Cycles in the mining/quarrying industry

The Life Cycle Assessment (LCA) methodology is increasingly being worldwide used and appreciated as a comprehensive tool to understand the environmental implications of products/goods along their whole life cycle.

There are several reasons that explain this growing interest.

Among them, LCA:

(1) is quantitative and objective, i.e. it measures the environmental impacts by using quantitative and internationally recognised indicators and models;

(2) allows quantifying direct and indirect impacts, i.e. impacts which are upstream and downstream in the value chain, therefore avoiding “problem shifting” and ineffective solutions;

(3) is comprehensive, as it can be used to understand a variety of environmental aspects, at different scale and time boundaries;

(4) is transparent and fair, as it points out both strengths and weaknesses of direct or reverse supply chains;

(5) is internationally standardised and recognised by a number of decision-makers and stakeholders.

Nowadays, an important part of the environmental information used to interpret, forecast or design sustainable development issues related to industrial systems or, more in general, human activities is derived from an application of LCA or a life cycle approach.

In spite of such a great interest (and expectations) on life cycle issues, although the general LCA methodology is well defined, there is still lack of sector-specific standardisation in many fields.

The mining/quarrying industry is one of the sectors in which there have been relatively less use of LCA based tools, or where the use of LCA has received less consensus. A comprehensive analysis is beyond the scope of the present guidelines, but a short overview can be helpful for the SARMa participants.

First of all, it must be said thatpotential users of LCA are often discouraged by its data and knowledge intensity. Moreover, aggregate producers are often small or medium sized enterprises (SMEs), thus they rarely hold the expertise needed to properly run a LCA. However, thesereasons alone cannot fully explain.

LCA can more effectively be applied to standardised production systems, while extractive activities always differ from one another. Thus, while production of polyethylene is more or less similar worldwide, it is incorrect to assume that all mines or quarries or processing plants will impact the environment equally (van Zyl, 2005). This is an obstacle for standardisation and adoption of LCA.

Availability of site specific data is a real concern, as average Country/Area data retrievable from databases are often not representative of the systems under study. According to Reid et al (2009), environmental impacts of mining activities have to be evaluated using site-specific data, otherwise there is a real risk of getting to misleading conclusions.

LCA is more effective in quantifying environmental impacts of production systems at global level, while extractive activities impact relatively more at the local/regional level, for which available indicators and impact models are less developed, or received less consensus. Land use and/or land transformation are typical examples for which there is a huge interest and relatively less well established impact assessment methodologies.

However, there is another important reason for making LCA application to the mining/quarrying sector unique. This reason originates from some of the most important economic peculiarities of mineral resources.

As a geological legacy, mineral resources are located in well specific sites (with their site-specific unique characteristics) and, as non-renewable resources, every mining project has a finite life cycle (van Zyl, 2005), with each life cycle step impacting the environment (see Fig. 1.1).

To run a mine/quarry project, heavy infrastructures/plants/facilities (Assets, in general) must be constructed/developed, but they also have a life cycle made of phases with their environmental implications. The quarry itself, or part of it, can be regarded as an operational activity (asset).

Mine operation generates mineral products (metals, aggregates, industrial minerals, etc.) that, as products, have their own life cycle and are part of a supply chain.

Three inter-dependent life cycles are thus identified (see Fig. 1.1), which need to be integrated and jointly understood in terms of sustainability implications:

(1)Life cycle of mining/quarrying projects;

(2)Life cycle of mining/quarrying assets;

(3)Life cycle of mining/quarrying products.

Aggregates (minerals, in general) are valuable resources used in economy, thus their contribution to sustainable development should be the focus of the analysis. The leading approach should therefore be the product life cycle, but with an holistic life cycle management (LCM) of the three life cycles. This holistic LCM will be one of the specific objectives to be achieved within SARMa.

Figure 1.1 – Integration of the three life cycles in the mining/quarrying industry

While it is certainly true that also for other products, in other sectors, it is possible to distinguish between Project, Asset and Product life cycles (see Brent, 2005), the joint management of the three life cycles is much more important in the mining industry, for at least two reasons.

(1)In the mineral industry the Project life cycle is limited by the non-renewability: when the orebody is depleted, the mine is over and it’s usually impossible to duplicate the project in the same site (there can be temporary closures or future conditions to mine, see van Zyl (2005), but this would complicate the approach even more).

(2)For many products/goods the environmental implications relevant to Project and Asset life cycles are usually negligible, in comparison to the Product life cycle impacts, while for the mineral industry this is usually untrue.

For these reasons, the LCA methodology proposed for SARMA will be focused on the Product life cycle, but with an integration between Product, Project and Asset life cycles.

It should be mentioned that LCA practitioners usually refer production equipments and facilities as “capital goods” or “capital equipment” or “infrastructure” (see , Frischknecht et al. 2007), which fall within the above mentioned general term “Asset”.

1.2 Implementation of the LCA methodology in SARMa

Within SARMa, the implementation of the LCA methodology is divided in three steps (see Fig. 1.2). Step1 is limited to the analysis of the from-cradle-to-gate environmental implications (eco-profile) of natural aggregates (NA), in other terms, the first part of the product life cycle plus the mine life cycle + mining assets life cycle.

Figure 1.2 – Steps of the LCA implementation within the SARMa Project

In step 2, the LCA methodology is extended and adapted to the production of recycled aggregates(both construction and demolition waste C&DW recycling and quarry by-products recycling) with the overall objective of pointing out resource and environmental strengths and drawbacks of real recycling activities and chains.

Finally, instep 3 a comprehensive methodology will be proposed in order to assess the environmental performances of a real system in which natural and recycled aggregates co-exist and where quarrying + recycling + transportation network + alternative end-of-life scenarios are balanced in order to optimise energy and environmental efficiency at system level and learn more about a desirable sustainable supply mix (SSM).

In the present version, methodological guidelines are limited to step 1: LCA of natural aggregates (eco-profile).

1.3End-use of aggregates and Functional unit

LCA is often used to compare products, based on their resource and environmental profile. However, comparisons must be objective and fair.

As a consequence, the choice of a meaningful functional unit as a reference flow for the results of an LCA must be strictly connectedwith the function of the system under study.

This is because comparative LCAs are meaningful if the studied products fulfil the same function.

Thus, the functional unit should be defined so that different products (within SARMa: construction aggregates) being compared provide the same services, for similar end-uses and duration.

Also in case LCA is not finalised to a comparison, the eco-profile is meaningful only if it can be associated to a product of well defined characteristics.

Technical properties of aggregates and their potential end-uses must be defined, as that kind of informationmust be considered an essential background of construction aggregates LCAs.

As it will be later on discussed, aggregates quality must be dealt with in different stages of the life cycle assessment.

This said, the adopted Functional Unit is 1 ton of aggregates, associated with one (or more) parameter describing the product quality, or the potential end-uses.

1.4 System description and System boundaries

The Product System to be described can be any kind of aggregate quarry(wet/dry, small/large), which produces different aggregate products (sand, round/crushed gravel, tout-venant, etc…) from different orebodies (alluvial deposits, igneous rocks, etc…) and with different excavation techniques (blast/mechanical).

Thus, LCAs should begin with a description of the natural resource to be mined, the natural (or built) environment which hosts the extractive activity, the quarry itself, the quarried products, the quarrying equipments and activities.

Such a technical description is used as a background to set up the LCA model, which is usually developed under a LCA software.

The LCA research group at the Politecnico di Torino has used both the Boustead Model and SimaPro software packages. The present guidelines are more easily applicable to the SimaPro software, but can be adapted to any other LCA software.

As the LCA of natural aggregates is concerned, the system boundaries, i.e. the activities/products to be accounted for in the model, are those included in the dashed box corresponding to step 1 in Fig. 1.2.

In order to rationally integrate the three life cycles of Fig. 1.1, the LCA model can be built up according to the inter-linked unit processes described in the framework of Fig. 1.3.

Figure 1.3 – Implementation of the three Life Cycles into a LCA model made of inter-linked unit processes

The scheme reported in Fig. 1.3 shows the unit processes that should be included in the LCA model. As it can be seen, some of them belong to the Mine life cycle, some can be ascribed to the life cycle of some Assets and some are a mix that can be connected to all the three life cycles.