3.12 CONTAMINATED SITES

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1 3.12 CONTAMINATED SITES INTRODUCTION The term contaminated sites refers to industrial sites and landfills where pollutants have leached into the ground and groundwater in the past as a result of poor handling, leakage, accidents or inadequate technical safety measures, and are thus causing a risk for the environment and human health. The problem of the contaminated sites issue became known in the early 1980s when several incidents of spectacular groundwater contamination in the vicinity of landfills attracted the attention of the general public and gave cause for concern. In 1989 the Altlastensanierungsgesetz (ALSAG) [Law for the Clean-up of Contaminated Sites (Federal Legal Gazette 299/1989 as amended)] was adopted, which provides primarily for the financing of remediation. Environmental requirements for industrial sites and landfills have seen a marked rise in the last 20 years and plant technologies have improved accordingly. One can assume that the industrial sites licensed today and operated according to the rules do not pose a risk to soil and groundwater. Since the coming into force of the ALSAG, contaminated sites have been registered Austria-wide. Until a site is found to require remediation, a few - sometimes costly - steps have to be taken, ranging from the identification of suspected contamination resulting from previous activities on the site to the detailed evaluation of the results from investigations of extensive sampling (soil, groundwater, soil air) and analyses. A central database stores the contaminated sites contained in the Register of Contaminated Sites as well as suspected contaminated sites (Register of Suspected Contaminated Sites). Information is also made available to the public on the Internet. The Umweltbundesamt assumes that there are about sites nationwide where substances dangerous to health and environment were handled in the past or are still handled. A need for remediation exists at an estimated sites. For a currently inestimable number of sites causing no major risks, a limited use must be expected ENVIRONMENTAL POLICY TARGETS Pollutants from contaminated sites may leach into the soil and groundwater and thus cause a risk for human health, depending on how these media of protection are used. The lasting protection of soil and groundwater resources therefore has a high priority. Environmental targets have been formulated as follows: 227

2 Targets of sustainability. The Austrian strategy on sustainable development (Bundesministerium für Land- und Forstwirtschaft, Umwelt und Wasserwirtschaft (BMLFUW) [Federal Ministry of Agriculture, Forestry, Environment and Water Management], 2002; see also Chapter 1.1) stipulates the protection of soils and the sustainable use of the valuable resource water as targets. Groundwater protection. The Wasserrechtsgesetz (WRG) [Austrian Water Act (Federal Legal Gazette 1959/215 as amended)] defines groundwater as drinking water and stipulates that in the event of groundwater contamination, appropriate measures have to be taken to prevent any risks. Risk assessment of contaminated soils. The Austrian Standard (ÖNORM) S Risk assessment for polluted soil concerning impacts on surface environments provides instructions for the assessment of contaminated soils. The underlying approach is a use-oriented one. This means that for more sensitive uses such as gardening or playgrounds, soils with a defined contamination are considered to pose a higher risk than when used as industrial or commercial sites SITUATION AND TRENDS The recording of sites Since the coming into force of the ALSAG in 1989, contaminated sites have been recorded Austria-wide. At the instigation of the BMLFUW, the recording is carried out by the Umweltbundesamt in cooperation with the governmental authorities of the Federal Provinces and is coordinated by the BMLFUW. The designation of a site as a contaminated site is the result of a lengthy process involving several steps. This process ranges from the registration of the site as a result of previous activities on the site, to the detailed evaluation of the results from investigations with extensive sampling (soil, groundwater, soil air). An assessment of contaminated sites involves three different steps of information (see Table ). Site class Information content Sites recorded to date Recording level* registered sites little, reference to former vsite activities about 50% result of preliminary assessment on the basis of a suspected contaminated site defined basic data record about 16% contaminated detailed investigation programme site 222 about 9% Tab : Information content for sites with regard to the evaluation of their risk. * as of , estimated Old deposits and industrial sites In this context, the term old deposits is used for sites where wastes had been deposited until 1989 (old landfills), and old industrial sites for plants where sub- 228

3 stances dangerous to the environment had been handled until the same year. As of 1 January 2004, about such sites were recorded, which is about half of the estimated sites. The recording level in the Federal Provinces is shown in Figure Districts with high recording levels are mainly found where governments of the relevant Federal Provinces have implemented targeted programmes for the recording of sites. Trend: The recording level for these sites will see a marked increase within the next few years as several recording programmes are currently planned or being implemented. It is expected that all old deposits and industrial sites in Austria will be recorded by about Upper Austria Salzburg Vienna Tyrol Carinthia Burgenland Styria Lower Austria Vorarlberg Old industrial sites Old landfills Recording level % Fig : Estimated recording level of old deposits and industrial sites in the Federal Provinces. Suspected contaminated sites Suspected Contaminated Sites are old deposits or industrial sites where a preliminary assessment of the risk potential has been carried out and a suspected considerable risk to man and environment has been identified. On 1 January 2004, suspected contaminated sites were listed in the Register of Suspected Contaminated Sites (see Table ). Trend: The recording level is low for suspected contaminated sites, and for former industrial sites especially. A method for the systematic identification of suspected contaminated sites Austria-wide is currently being developed so that it will be possible to complete the recording of contaminated sites in the medium term (20 years). Type of suspected contaminated site Recorded to date Recording level old landfills about 60% old industrial sites 227 about 2% Total about 16% Tab : Estimated recording level of suspected contaminated sites. 229

4 Contaminated sites Contaminated sites are old deposits or industrial sites that, according to the results of a risk assessment, have been found to pose a considerable risk to human health or the environment. The urgency of their remediation is expressed in three priority classes. Between the time when the ALSAG came into existence and a total of 222 contaminated sites were designated. This corresponds to an estimated recording level of about 9% Austria-wide. It has to be assumed that several major contaminated sites have been recorded already. Of these contaminated sites, 45 were allocated to the highest priority class for remediation. Trend: The current procedure allows a more or less complete recording of the sites in Austria only in the long term. Only speeding up the investigation and risk assessment can change this Investigations, evaluations and remediation Investigations of suspected contaminated sites To assess the actual environmental risk of a suspected contaminated site, detailed investigations are necessary. Under the ALSAG, investigations were arranged at 348 sites (see Fig ), 60% of which were old landfills and 40% old industrial sites. Trend: Experience from already completed projects has shown that there is a potential for the simplification and, to some extent, standardisation of investigations. Investigation com pleted 40% Investigation in progress 60% Fig : Current state of the investigations of suspected contaminated sites (348 sites). Especially in minor cases, costs and time should be saved in future. This would mean that the known suspected contaminated sites could be investigated within 15 to 20 years. 230

5 Risk assessments designation of contaminated sites Risk assessments are the basis for the designation of contaminated sites. To date, risk assessments have been carried out for about 309 sites. Of these, 222 have resulted in the designation of contaminated sites. The estimated total number of required risk assessments is about Trend: It is expected that a large part of the risk assessments that remain to be conducted for old landfills will not result in the designation of contaminated sites. This is because in the past, priority used to be given to especially urgent cases with a strong probability of a high risk potential. The situation is different with former industrial sites, where larger numbers of sites with a considerable risk potential are still expected. The remediation of contaminated sites Between the coming into force of the ALSAG and , 222 sites were designated as contaminated sites. For about half of these, the remediation has either been completed or is currently under way. As regards the rest, remediation is still pending (see Fig ). There are several cases where a remediation has been carried out but not under the ALSAG. This is the case when the use of the site has a high subjective significance and where somebody pays the costs of the remediation, or in minor cases where the remediation is carried out as part of building activities. This happens mostly in the case of urgent building projects (such as rebuilding a petrol station, road construction) and when simple remedial techniques (soil excavation and landfilling) are applied. Remediation com pleted 24% Remediation planned 53% Remediation in progress 23% Fig : Current state of the remediation of contaminated sites (as of January 2004.) Technologies applied for remediation An analysis of the technologies applied for remediation in Austria to date shows that conventional processes such as excavation, incapsulation and groundwater treatment (pump & treat) are still most commonly applied. Innovative processes are still hardly used for various reasons, especially because of a lack of experience, inadequate residual risk assessment and worries that such processes may not be ac- 231

6 cepted by the competent authorities. In the future it will be necessary to promote innovative technologies for remediation and to overcome the barriers preventing their application. Restorage on site 8% Degassing; soil vapour extraction 11% On-site technologies 2% Other 2% Excavation 25% Surface sealing 12% Pump & Treat 18% Incapsulation 22% Fig : Techniques for the remediation of contaminated sites (104 sites) SUMMARY ASSESSMENT AND OUTLOOK The recording and remediation of contaminated sites in retrospect Much has been achieved since the ALSAG came into force in In addition to several small sites, major sites presenting environmental threats on a large scale have been cleaned up. The methodology for recording and assessing contaminated sites has progressed enormously and nearly all data collected with the recording of contaminated sites are easily accessible for the public in a comprehensible format on the Internet. The fund for the remediation of contaminated sites makes possible the investigation of several sites every year according to nationally listed priorities, as well as the identification of the need for action. Nevertheless it should be noted that with the means currently available and with the current methodology, it will not be possible for all relevant sites to be recorded, assessed and cleaned up in the next few decades. But the experience gained in the last few years has yielded results that may help to optimise the procedure. Social and economic advantages of secured financing The recording and remediation of contaminated sites is largely financed with means from the fund for the remediation of contaminated sites. The money in this fund comes from a tax on wastes and amounts to about 70 million Euro every year. The 232

7 fund is essential for the recording and the remediation of contaminated sites. The remediation of contaminated sites always involves large sums of money. In all cases, the contamination was caused a long time ago and a polluter is either difficult to find or no longer exists, or is maybe not able to pay. It was not until secured funds were available that several of the larger contaminated sites were cleaned up and a systematic recording system was established. With this system of financing, Austria is unique, together with Switzerland, by international comparison. The annual market value of the recording and remediation of contaminated sites in Austria is estimated at 140 million Euro and consists of contributions from the contaminated sites remediation fund, private contributions and contributions from the Federal Provinces. The remediation of contaminated sites is thus, apart from preserving high-quality water and soil resources, a respectable economic factor and guarantees a large number of jobs. Brownfield redevelopment - a new impulse for contaminated sites management? The problem of contaminated sites can be solved only in the long term. Apart from improvements and simplifications of methodology and technology, new strategies are also needed. Sealing and urban sprawl are increasingly causing a major environmental problem also in Austria (see Chapter 3.5). There are about old industrial sites in Austria with an unknown contamination pattern. Of these, 20% are currently not used. Many of these sites have an excellent infrastructure. But investors still prefer new locations for industries and residential purposes on undeveloped land ( on the green ) because many risks do not present themselves here. These risks include the question of liability if a remediation of the site is required potential limitations to the use of the site (such as the impossibility to use the site as a garden or playground) due to contamination financial requirements for the elimination of risks and a difficult to estimate loss of time as a result of remedial measures. Therefore, incentives for brownfield redevelopment ought to be created with a view to soil protection and spatial planning. The redevelopment of brownfields may be a new impulse supporting the solution of the problem of contaminated sites. It would be necessary to create new incentives here to redevelop old deposits and industrial sites in order to reduce greenland consumption Target values Currently there are no clear targets in terms of time and quality for contaminated sites management. There are no binding requirements at federal level referring to the question of whether and to what extent any residual contamination may be tolerated after the completion of remedial activities at contaminated sites. The authorities and experts are therefore caught between modern environmental legislation 233

8 guided by the precautionary principle, and the limited technical and financial possibilities available for the remediation of mistakes committed in the past. This leads to either elaborate and expensive remediation in the individual case, or to solutions with as little effort as possible. The risk is therefore that the ecological benefit derived from the remediation of contaminated sites is achieved only with an enormous effort involving large shares of the national account. As generally recognised procedures and target values are not available to assess such criteria, the possibilities for comparing studies of different options and thus an optimised remediation are limited RECOMMENDATIONS Binding environmental quality targets are urgently recommended for the assessment of soil contamination caused by past activities or landfills. From the viewpoint of the Umweltbundesamt, long-term targets of environmental policy for the management of contaminated sites ought to be developed and defined in the light of sustainable resource management. To this effect, a revision and re-orientation of the legal principles for the management of contaminated sites would be required. A new law on the procedure for contaminated sites might be a solution, or an adaptation of existing laws in other fields such as the water law and waste law. The following table proposes the major target values and defines them. Problem Missing target value Number of contaminated sites requiring remediation; Remediation of contaminated sites Time frame for remediation; Quality of the remediation Brownfield redevelopment Extent of annual redevelopment Recording of contaminated and suspected contaminated Time frame for completion of recording sites Tab : Target values for the management of contaminated sites (examples). The management of residual contamination after remediation is a problem still largely unsolved, as well as the definition of use-oriented remediation targets. Also, the legal situation for the management of minor contaminated sites could be clarified by creating a new legal framework (see above). With the amendment to the ALSAG (Federal Legal Gazette 71/2003), the basis for the support of remedial measures was adapted to the changes in the overall conditions and secured for the following years. Because of the major importance of the financial support, the financing of the remediation of contaminated sites under the ALSAG must be secured. Also, incentives ought to be created for private financing to speed up remedial activities at contaminated sites Austria-wide. 234

9 The speeding up and simplification of contaminated sites management under the ALSAG is recommended. Such potentials exist for the systematic recording of contaminated sites and the investigation and risk assessment of sites. A simplified procedure could be achieved by standardisation in uncomplicated cases. Innovative options for remediation should receive targeted support. This could be achieved by intensifying the cooperation of financing bodies and competent authorities, in particular with regard to defining use-oriented remediation targets. The development of additional strategies is proposed for a quicker management of the contaminated sites problem. A new impulse is the redevelopment of brownfields. New incentives ought to be created by the Federal Government and the Federal Provinces for re-developing old deposits and industrial sites, putting a halt to the growth of built-up area and for speeding up site remediation. The following aspects ought to be included: create profitable incentives for brownfield investors: offer joint liability for State and investors or define the investor's maximum liability put a halt to greenland settlement, define appropriate targets and set up control mechanisms establish agencies for redevelopment at federal level and at the level of the Federal Provinces. 235