Waste audit – securing good quality raw material from construction and demolition waste

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International HISER Conference on Advances in Recycling and Management of Construction and Demolition Waste

21-23 June 2017, Delft University of Technology, Delft, The Netherlands

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Waste audit – securing good quality raw material from construction and demolition waste

Wahlström, M.1, Hradil, P.2 and Arevalillo A.3 1

VTT Ltd, P.O. Box 1000, FI 0240 VTT, Finland, Phone +358 40 584 7390; E-mail: margareta.wahlstrom@vtt.fi

2

VTT Ltd, P.O. Box 1000, FI 0240 VTT, Finland, Phone +358 40 0209 593; E-mail: petr.hradil@vtt.fi

3

Tecnalia, Área Anardi, 5, E-20730 Azpeitia - Gipuzkoa (Spain), Phone +34 946 430 850; E-mail: alfonso.arevalillo@tecnalia.com

Abstract

Pre-demolition audit or waste audit is the tool to assess the materials to be removed from the building or infrastructure and their potential value by external experts prior to the demolition or renovation activity. Such audits are essential since they enable all stakeholders involved to get information of the composition of waste and make it easier to find markets for different waste types. The development of guidelines for waste auditing is one of the action points of the Circular Economy agenda of the European Commission. It is likely that the Commission will recommend member states to make the waste audit mandatory in order to increase the quality of recycling. A framework for waste audit was developed in a contract work financed by Commissions’ DG for Internal Market, Industry, Enterprises and SMEs (GROW) [1]. The guidelines are establishing the basic principles of waste auditing, identification, reporting and recommendations for the further treatment. This paper presents the basic needs and benefits of such harmonized approach to the waste auditing including good practices from the selected countries. It should be noted that the number of materials separated due to their dangerous nature is growing and the methods for the identification of contamination are better which can result in a slight decrease of recyclable materials, but in a better quality of the materials that are recycled.

Keywords: pre-demolition waste audit, guideline, construction and demolition waste, hazardous substances.

Development guidelines for pre-demolition waste audits

The aim of the DG GROW study [1] was to develop a methodology guidance for pre-demolition audit. The starting point for the study was a survey collecting the stakeholders’ views on the current regulation and practice in selected countries. Waste audits are mandatory (with certain limitations) in some countries, but seldom done. According to HISER project [2], as a rough estimate, in Flanders a pre-demolition audit is present in only ca. 5% of the cases. However, in all countries, most of demolition contractors make their own pre-demolition survey for their internal use and to calculate the price of the works to be performed. Several interviews claim that audits do not provide enough detail. Sometimes doubts arise regarding the training of the people performing the audits and in some cases on the reliability of the audits. Regarding dangerous substances, the main focus is on asbestos. However, the legislation concerning PCBs and other hazardous wastes has been recently implemented in several countries.

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General observations

- The testing and sampling requirements are mostly not defined in the legislation, however, methods to identify hazardous materials and contamination are usually recommended in guidelines.

- Inventories of hazardous substances (especially asbestos) indicate the presence of asbestos, but not always its location and amount. Also, there is an added obstacle in the hidden dangerous substances that usually lead to extra costs and in some cases to stop the works.

- Some industries consider that asbestos inventories should be more professional while others request less paper burden and a quicker answer from the public administration issuing the permit regarding the disposal of asbestos.

- The minimum content of these assessments generally include, identification (usually according to the classification based European List of Waste or European Waste Catalogue) and quantification (in weight and volume).

- Procedures for developing these inventories in most countries are stated in regulations, including the way to be performed and by whom.

Most countries allow visual inspections complemented with either desk studies or computer applications. There are a few different guidelines and supporting tools throughout Europe for the preparation of these audits; by way of example:

- A computer application in the Basque Country supports the estimation of wastes coming from works by applying some ratios that depend on the type of activity, type of building, size, etc. The demolition contractors interviewed claim that it tends to overestimate quantities and cannot forecast any peculiarity of the building)

- Methodological guidance on CDW management and online waste reporting and tracing system in the Czech Republic is issued and maintained by the Ministry of Environment.

- A “Demolition Protocol” was issued by civil engineers association in UK. BREE has also information procedures.

- In Belgium, several Guidelines and tools are available: MEDECO (MEtré des DEchets de Construction); Tracimat – Belgian example of a CD waste tracking [2], Guidance document for drawing up a demolition inventory (Flemish Region); Reuse of building materials-Practical guide (Walloon Region)

Guideline – Key elements

The auditing process aims to deliver such documents that the owner can submit a building permit application and open a call for deconstruction tenders. Furthermore, the outcome of the auditing should also provide a reliable basis for the order of a contractor concerning demolition waste. An effective process for carrying out a waste audit should follow the steps depicted in Figure 1.

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Figure 1. General scheme of waste audit The steps in the scheme are following:

1. Desk study: collection of all the relevant information from the documentation of the building or other work (age, drawings, materials used, hazardous materials etc.) 2. Site visit: visual inspections, comparisons with collected documents, planning of

inspections and measurements, preliminary planning of deconstruction techniques and waste handling on site as well as communication between actors engaged by the owner to the process. The audit can be organized by the owner or any actor on his/her behalf

3. Materials assessment: the materials assessment is a summary of the amount of waste (in mass or volume) in the various European waste classes

4. Site recommendations: Suggestion for opportunities to increase recyclability (also reusability) of materials and construction products to minimize the disposal or incineration of the waste

Proposed Implementation

The EU legislation (Waste framework directive, List of waste, etc.) and EU guidelines (CDW Management Protocol [3]) form the base for the implementation of the pre-demolition audit. However, most of the implementation has to be decided on national level. Some of the basic elements to be defined on national or regional level for the implementation of the waste audit are following:

- Thresholds (minimize size, conditions, materials…) for executing the mandatory audit or its parts (if any)

- Templates or electronic forms for waste audit reporting

- Methodologies for sampling and materials identification and hazardous materials detection

- Required skills and certifications for the auditors - Best practices in waste identification and reporting

- Regulations for waste sorting, landfill and waste treatment - Incentives to support waste treatment, separation and reuse.

On the other hand, several supportive actions from the EU would be also beneficial for the smooth audit implementation such as for instance:

- Clear definition of waste holder’s responsibilities. It is recommended that the waste holder is responsible for the knowledge of amount and nature of the produced waste. - Regulatory framework for reused building elements

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297 Needs

The needs and impacts vary dependent on the stakeholders, for instance:

- owners, contractors or waste managers, for which the value of waste and deconstructed materials (incl. prevented waste) is important, e.g. how to maximize the end-of-life value of building or infrastructure through the planning of waste prevention and reuse.

- consultants and professionals of demolition companies, which believe a pre-demolition audit can promote improvements in pre-demolition activities and increased quality of demolition waste

- professionals of demolition companies, which see opportunities in improved demolition activities due to increased material values and reduced waste management costs

- recycling companies, which benefit from increased C&DW quality through the production and selling of good quality raw materials

Conclusion

A harmonized concept for pre-demolition waste audit will improve the availability of high quality raw materials from construction and demolition activities. It will also enable more efficient cross-border trade of waste and deconstructed materials.

Acknowledgement

This paper is based on information collected in the contract study [1] funded by the Commissions’ DG for Internal Market, Industry, Enterprises and SMEs (GROW).

References

[1] EC “Technical and Economic Study with regard to the Development of Specific Tools and/or Guidelines for Assessment of Construction and Demolition Waste Streams prior to Demolition or Renovation of Buildings and Infrastructures”. Final report of EU Specific Contract 30-CE-0751644/00-00 – SI2.720069 (2016).

[2] EU H2020 HISER project: www.hiserproject.eu

[3] European Commission “EU Construction and Demolition Waste Protocol”, available online from http://ec.europa.eu/growth/ (2016).