Management of Contaminated Sites and Land in Central and Eastern Europe

Slovenia

Country Characterisation

When considering the natural characteristics of Slovenia, the following must be emphasised:

	High relief - only 10% of Slovenia is lowlands, and together with valleys and basins only 18%. In these areas, rivers, arable land, main urban areas, and economy and traffic infrastructure are concentrated, and represent the heaviest burdens and highest pressures on nature. Most of the landscape is hilly and mountainous; there are even areas with high mountains.
	Slovenia is a mosaic of at least 50 different kinds of rock types, and several hundreds soil types. This, in combination with different climatic belts, caused the development of various ecosystems and biotops.
	44% of Slovenian territory is karstic with an underground system of caves and rivers.
	Slovenia is rich in water sources, mainly groundwater and springs, which are an important source of drinking water.

Concerning land use, forest account for 53% of the country’s surface, 42.6% of land is agricultural, but only 14.6% are arable land. Other uses account for 4.4%. Slovenia has relatively few protected areas and only one national park. They cover about 8% of the territory (approx. 122.000 ha).

There is only 1246 m² of arable land per inhabitant, which is not enough for self-reliance, especially at the present state of technology. The message is clear: we must preserve every piece of arable land, because lost fertile soil cannot be replaced through amelioration of soils with less favourable properties. Changing nature requires great risks and large investments; intensification should be redirected towards biotechnological findings, which would enable the production of enough of healthy food to meet basic needs. The socio-economic strategy of the preservation and improvement of agriculture and the countryside is important. Science should help determine land use, and develop new technologies for food production. We all share the responsibility to make sure that their processes are environmentally friendly.

Soil pollution by heavy metals, such as Cd, Pb, Cr, Cu, Zn, Hg and pesticides and other organic contaminants, nitrates and in some cases phosphorus is a problem of concern. Although heavy metals are present naturally in soils, contamination comes from local sources, mostly industry, power plants, iron and steel and chemical industry, zinc smelters, use of irrigation water, sewage sludge, road traffic etc. Also agriculture contributes to the eutrofication process and to pollution with toxic substances (pesticides), which both affect ecosystems.

Some landfills in Slovenia are still in use and some belong to the past. For old industrial landfills not used anymore it has been decided to carry out rehabilitation measures of the affected areas. Studies on sanitation and rehabilitation have been made for a range of identified industrial landfills. However, rehabilitation activities are slow due to the lack of financial means and also unsolved land ownership issues.

Legal and Administrative Basis

Definition of Contaminated Sites and Land

There is no specific definition for contaminates sites and land.

Legislation

Changes in the political and economic system and the independence of the Republic of Slovenia, the decision for Slovenia to move towards the European Union and replacing the complete legal order with the legal order of a Western Democracy, governed the decision for legislative reform also in the area of protection of the environment. On a new constitutional basis, Parliament passed the Act on the Protection of the Environment in June 1993 (Official Journal of the Republic of Slovenia, No. 32/93). The Act contains general provisions and basic methods of protecting the environment and exploiting natural resources. On the basis of the Environmental Protection Act, new legislation regarding soil protection has been adopted in Slovenia recently.

1. In purpose to set up maximum allowed values of dangerous substances in soil the Decree on the Limit, Warning and Critical Concentration Values of Dangerous Substances in Soil was adopted in 1996 (Official Journal of the Republic of Slovenia, No. 68/96).
   The decree defines the soil as a surface part of the lithosphere, which consists of mineral and organic substances, water, air and organisms.
   Concentrations of seven classes of pollutants were determined: heavy metals, inorganic pollutants, aromatic compounds, polyaromatic hydrocarbons, chlorinated organic, pesticides and others. This is particularly important in those soils, used to produce foodstuffs.
   Values below the maximum allowed represents the uncontaminated soils and values over critical concentrations means that a clean-up is necessary. Values over warning allowed values indicate that further investigation is required.
2. A Decree on Input of Dangerous Substances and Plant Nutrients into the Soil (Official Journal of the Republic of Slovenia, No. 68/96) was also adopted in November 1996 in order to regulate the input of fertilisers (both mineral and organic: manure or slurry) and heavy metals into soil. The decree defines limit values for amounts of heavy metals which may be added annually to soils, and limit values for amounts of plant nutrients, which may be added annually to soils with manure or slurry (inorganic fertilisers not included).
   In areas with shallow groundwater, used for water supply the decree is trying to narrow the imbalance between fertilisers input and crop uptake with following measures:
   – limit input values for nutrients (fertilisers) regarding crop uptake,
   – application of fertilisers at the proper time (in the growing season),
   – sowing winter crops to minimising leaching losses, etc.
   Increased nitrate concentrations in groundwater, which have exceeded the limit value, have been detected. The increased nitrate contents were ascribed to the intensive agricultural activity, so the measures are important to prevent the pollution of drinking water.
   The decree also controls the use of sewage sludge from treatment plants, compost and slurry in agriculture by setting limit values for concentrations of heavy metals. The use of sewage sludge, compost or slurry is controlled by permission given by the ministry of environment.
3. Regulation on the Operation Monitoring of the Input of Dangerous Substances and Plant Nutrients into the Soil (Official Journal RS, 55/97) defines the types of parameter for soil, sludge from treatment plants, compost and slurry which are the subject of operation monitoring of the input of dangerous substances and plant nutrients deposited in the soil with sludge from treatment plants, compost and slurry from riverbeds and lakes (hereinafter: operation monitoring), the methodology of sampling and measuring the parameters, and the contents of the report on operation monitoring. This Regulation defines the conditions required from the person who conducts the operation monitoring.

Furthermore, the assurance of groundwater quality is laid down in the Law on Drinking Water (Decree of July, 1997).

Also it is noted that concerning waste management there exists an Integrated Waste Management Strategy from 1992.

Implementation of Limit Values

Soil monitoring system in Slovenia

The assessment of soil and vegetation pollution is based on 8 X 8, 4 X 4, 2 X 2, or 1 X 1 km grids. Foreign and domestic experience has shown that a systematic survey of soil pollution requires that denser network be established, taking into consideration various factors that influence the level of soil and vegetation pollution including, among others: urbanisation, industrialisation, air pollution, type and properties of the soil, lithological base, soil utilisation, and precipitation.

At the moment, we only have soil pollution data for around 8% of the territory.

Soil pollution by heavy metals

The results of upper soil samples showed that Cd, Pb and Zn exceed the limit values in the city of Celje and its vicinity. Celje County lies in the middle of Slovenia in a topographic basin surrounded by hills and mountains, characterised by frequent temperature inversions, especially in the winter months. This is the main reason why stack emissions from local smelting industries are widely spread over the basin.

In Ljubljana the main problem regarding contaminated soils is lead from road traffic. Higher zinc and copper contents in the soil occur only occasionally.

In Jesenice, where the iron industry is located, higher Cd, Zn, Fe and As contents were found.

Soil pollution by pesticides and other organic contaminants

Of 21 potential harmful substances only triazine herbicides and DDT derivatives were detected locally in samples from the agricultural land, but did not show any substantial concentrations in soils. These substances are, or were in the past, used in plant production. The low levels at which these substances were found are not considered to be hazardous to human health.

Pesticide represent a problem in the areas with an intensive agricultural land use because of their leaching in the ground water. The quality of Slovenia’s ground water is deteriorating, mostly because of increased pesticide and nitrate concentrations, which come from intensive agricultural activity.

Other problems

Among other problems regarding soil degradation there are some data about soil acidification, especially in forests. Soil acidification is a natural process, but it has been enhanced by human activity through the emission of sulphur and nitrogen compounds from the combustion of fossil fuels and from industry emissions.

Another problem might be a salinisation in the NE part of Slovenia (because of semi-arid climate), caused by irrigation with improper drainage.

Groundwater

For groundwater, general monitoring of the quality based on analysis of selected parameters was started a few years ago. Generally, the groundwater quality is good although there is a trend of declining quality for some parameters. Based on the results of the monitoring, it was decided to monitor drinking water by samples collected at end points of the water supply systems. In 1995, it was decided to include some carcinogenic substances such as Pb, As and CHCl₃ in the monitoring, and in 1996 pesticides such as atrazine and alachlor and metabolites of these were also included.

For the parameters measured constantly and periodically in groundwater by the monitoring programmes, limit values has been determined. The parameters and the limit values are prescribed by the official gazette no. 46/97.

Due to contamination e.g. by pesticides, the groundwater quality is declining although at present the contents of the individual substances almost everywhere are below the prescribed maximum permissible levels.

Responsible Public Authorities

The Ministry of Environment and Physical Planning is responsible for the legal basis for the management of contaminated sites and land. Recently, the ministry has decided to expand its activities from the strictly legislative to more practical areas. Also, The Ministry of Environment and Physical Planning is responsible to ensure state monitoring of soil pollution according to the Environmental Protection Act.

The Ministry of the Environment and Physical Planning employs approximately 1000 people and is responsible for environmental issues, nuclear safety, regional planning, meteorology, and the monitoring of air and groundwater.

Directly under the authority of the Ministry of Health is the Institute of Public Health. It consists of 9 regional institutes (dividing Slovenia into 9 regions), of which the institute in Ljubljana is the core one. Its key responsibility lies in the analysis of food and drinking water.

The systematic monitoring of groundwater and drinking water is carried out more than 70 years, but since 1994 includes also monitoring of some carcinogenic substances in drinking water and continuos analysis of drinking water resources (wells and springs) and the analysis at the consumer level (from the tab).

Also, in 1997 an environmental inspection body began operating in Slovenia. The duties of this include the monitoring and registering of all events and activities connected with environmental pollution.

All the data regarding soil pollution in Slovenia are available at the Ministry of Environment - Nature Protection Authority. A Soil Information System in the Republic of Slovenia unites the soil databases: data on soil mapping in the scale 1:25000 and data on monitoring of soil pollution (five selected regions in Slovenia) into a logical whole.

SIS data will become the integral part of geo-oriented databases gathered at the Geoinformation Centre of Slovenia - still in the process of establishing and furnishing.

Sources of Soil and Groundwater Contamination

Because of the past human activities, some of the Slovenian regions are now polluted with heavy metals, pesticides, PCB etc. The pollution of soil can be a result of an intensive application of agricultural chemicals, traffic emissions, emissions from metal industry, waste disposal, and the incineration of fossil fuels (especially) rich in metals.

The source of pollution is often identifiable (specific production technology), but the incidence of multiple pollution in a single area is growing. Also, there are many "hidden", usually undetected polluted areas, which can only be defined with a very systematic and co-ordinated approach.

Soil pollution by heavy metals in Slovenia is a problem of concern. Contamination comes mainly from local sources (industry) and road traffic. Also agriculture (use of mineral fertilisers, manure, sewage sludge and pesticides) can contribute to soil contamination.

Monitoring of drinking water quality has been performed for many years. The monitoring has shown that the levels of certain parameters have significantly changed during the recent years. Thus, increasing contamination of groundwater resources have been seen in the last few years. Primarily, carcinogenic substances and pesticides are contaminating drinking water resources. The latter are caused by the intensive use of pesticides in agriculture. Other sources of contamination both with carcinogenic substances and pesticides may be the dumping of chemical waste at illegal dumps in the natural environment as well as various spills due to accidents or negligence.

Generally, groundwater quality is considered to be good. However, major problems are posed by diffuse contamination from agriculture, mainly pesticides. Especially older pesticides with arsenic compounds pose a pressure on groundwater. This problem is expected to be solved in the near future due to the abandonment of arsenic pesticides.

Military sites

The former Yugoslav army did in total run approximately 30 facilities with some 20,000 people. Slovenian military sites were not equipped with heavy weapons (such as missiles, chemical weapons etc.).

Along with the withdrawing of the Yugoslav army, a committee, consisting of various representatives from Ministries and Research Centres checked the contamination at some of the abandoned sites. This was done by on-site visits and by taking soil samples at the premises.

Contamination was identified at 2 sites only, in both cases hydrocarbon contamination (one site was the former military airport).

Waste Management

The total waste generation per annum is estimated to amount to approximately 800,000 tons.

Slovenia has 53 licensed landfills, of which 75% have already reached the limit of their capacity. It is estimated that the full limit will be reached within the next ten years. The licensed waste sites are in general equipped with a leaching control but only partly with surface sealing.

Apart from the licensed sites it is estimated that approximately 500 illegal landfills exist all over Slovenia. These sites are not equipped with any safety devices. Of major concern are pits in the carstic areas of Slovenia, which are used for waste dumping without any leachate protection. In carstic areas, groundwater has no or only a very low potential of regeneration (self-cleaning).

In 1992, the Ministry of Environment and Physical Planning published an integrated waste management strategy. For the future it is foreseen to build only a few (9 – 12), but very large waste sites which comply with the EU standards.

Slovenia has no waste incineration for domestic waste. There are 2 smaller incinerators, which belong to industrial facilities. One is the factory Lek in the Northeast of Slovenia, which produces pharmaceutical products the other is a pesticide factory, which incinerates returned packaging material.

Radioactive waste: Slovenia has one power plant, which is jointly operated together with Croatia. Low radioactive waste is currently kept at the premises and will soon reach the limit of storage capacity. There are plans to export the waste to Australia.

Hazardous waste: only waste contaminated with PCBs is transferred to France and incinerated there.

Industrial Structure

Today’s Slovenia has a mixed pattern of all industrial sectors. Decline and abandonment of heavy industry is not significant in Slovenia. In the former Yugoslavia, 40% of the exports were produced in Slovenia.

Two coal mines have been reduced in staff over the recent years and will probably be closed within the next decade (due to the minor caloric value of the coal and the high content of sulphur).

The car manufacturing plants have been abandoned.

One very large facility of the electronic industry, which employed up to 30,000 employees in the former Yugoslavia was restructured and reduced in size.

Number of Registered Contaminated Sites / Contaminated Land Areas

There is no estimate on the number of contaminated sites / land areas. However, it has been estimated that about 3500 – 4000 factories, plants and workshops in operation produce industrial wastewater.

The main source for identification of the potentially contaminated sites is the annual state report on the environmental protection, containing all the data on water, air, soil etc. pollution. A very good source of the information regarding contaminated sites is also some research projects and the reports from the Inspectorate for environment.

Methods for the investigation of soil pollution are covered by the above-mentioned Regulation on the Operation Monitoring of the Input of Dangerous Substances and Plant Nutrients into the Soil.

Up till now, no facilities exist for treatment of contaminated soil and there are any measure used. Slovenia has no experience in this field.

Slovenia has no experience with the remediation of contaminated sites. Only one remediation is known, which included the excavation of hydrocarbon contaminated soil.

Up till now no remediation activities are going on in Slovenia.

The Slovenian Government in December 1998 adopted a National Environmental Action Plan (NEAP). In the field of soil protection, the main goals are to prevent further chemical and physical contamination and to perform remedial actions where necessary and feasible. To realise these goals, a detailed action plan for the next five years is established including the estimation of the costs and possible sources of funding.

The transfer of property to a new site owner also includes the liability for environmental impairments. The new owner is hence liable for the clean-up.

If a contaminated real estate is sold, the buyer gets a cheaper price but has to guarantee the clean-up. Control is carried out via an ecological inspection of the Ministry of Environment and Physical Planning. Up to now, this system exists only in theory since no experience has been gathered.

The Republic of Slovenia has declared a commitment to take care of the clean-up of those sites, which are "commercially unattractive", such as abandoned mining facilities.

Slovenia has an ecological fund, which retrieves money from environmental taxes on air and water emissions. The ecological fund provides low interest loans for environmental protection measures. In the case of remediation activities support from the ecological fund is feasible.

Up till now, no data are available.

No data avaible

Illustrative Cases

For several industrial landfills, studies on sanitation and rehabilitation have been performed. The following description is made on this basis.

Soil Pollution in Celje County

Pollution monitoring of soil samples was first carried out in 1989 in the area of Celje County. The results of upper soil samples showed that Cd, Pb and Zn exceed the allowed values in the city of Celje and its vicinity. On some locations slightly higher concentrations of arsenic and nickel were found. 35 out of 119 examined soil samples contain more lead than allowed. Most of the 35 were from locations around the city and its industrial area. The highest Cd concentrations were also found in the centre of the city and the nearest surroundings. Maximum allowed Zn content in the soil of was exceeded in 36 soil samples. Higher arsenic and nickel contents in the soil occur only occasionally. Se, Hg, Ti, Cu and Cr concentrations were within legislative limits in all examined samples.

Since heavy metals can migrate from the soil to the plants or to the ground water when they are rinsed, it is of utmost importance to determine their mobility within the soil profile. Metal migration (Pb, Zn, Cd, As, and Ni) to deeper layers of soil (5-20 cm and 20-30 cm) was determined on selected points. In the majority of cases zinc, lead, and cadmium content in the soil decreases with depth in heavily polluted areas however, the concentration of these three elements is still above the allowed value in the depth of 5-20 cm, in some examples up to 30 cm.

Celje County lies in the middle of Slovenia in a topographic basin surrounded by hills and mountains, characterised by frequent temperature inversions, especially in the winter months. This is the main reason why stack emissions from local smelting industries are widely spread over the basin.

Landfill for uranium ore tailings from the mill in Zirovski Vrh

Uranium mining started in the area of Zirovski Vrh in 1982. However, due to high production costs and low prices, the Parliament passed the law on the permanent closure of mine in 1992. In 1995, an environmental impact report was presented together with the application for decommission permit in 1995.

One of the mill tailing disposal sites contain 620000 tonnes of tailings and 80000 tonnes of mine waste. The waste is situated on a potential earth slide, and since the drainage of the disposal sites has been stopped, the tailing and waste site slide has to be stabilised. This, however, require 7 million tonnes of material for stabilising the situation.

Industrial landfill for waste from organic acid production plant

The organic acid production plant (Tovarna Organskih Kislin (TOK)) producing mainly citric acid is one of the bankrupt companies in the Ilirska Bistrica region. The region lies in a karst region and sources of contamination threaten the groundwater. The Globovnik landfill near Ilirska Bistrica was used by TOK and presents a danger to the groundwater in the area. The landfill was used for disposal of residues from the production of organic acids at TOK as well as other solid and liquid waste mixed with household solid waste.

The most critical substances in the landfill are sodium hexacyanate, cyanides, CaSO₄, other hazardous waste, and all kinds of household solid waste. The landfill covers approximately 9 ha and is up to 10 m thick. The landfill has not been managed properly e.g. it is not sealed properly. An assessment of the environmental impact of the landfill has been prepared and a feasibility study for remediation is in preparation. It is expected that a programme for remedial activities will be completed and all necessary permits obtained by the end of 1999.

Industrial landfill for tar from the oil refinery in Maribor

In 1966, a landfill (Pesniška jama) was established for acidic tar from the oil refinery in Maribor. The landfill was used until 1983, when it was closed due to environmental problems. The landfill represents a typical tar cave divided into three layers. The upper layer consists of acid oil, the middle layer of acid water, and the bottom layer contains compact and partially hardened tar material.

Investigation results show that the liquid material in the landfill has a high acid content, mainly due to the presence of sulphuric acid and high contents of heavy metals such as Pb and As. Under the landfill, the soil is contaminated in an approximately 3 m thick zone. The groundwater in the area is contaminated in a narrow zone. A range of remedial measures has been proposed and evaluated by a feasibility study e.g. removal of acid water and treatment in a waster water treatment plant, incineration of tar and contaminated soil etc.

Industrial landfill for waste from a pesticides production plant (Pinus)

Waste form the pesticides production plant (Pinus) has been dumped at a landfill or cave named Kozoderceva jama. Analysis of drinking water from the area has indicated that the water contains pesticides. Further studies have shown that the source of the pesticide contamination is the industrial landfill Kozoderceva jama. A feasibility study on rehabilitation has been concluded. It has been suggested to remove contaminated soil from the site. One third of the contaminated soil can be disposed of in a landfill for urban waste and the remaining soil must be specially treated.

Industrial landfill for foundry by-products

Waste from a foundry has been dumped in a funnel shaped cavity in a limestone karst. Occasionally, a black sludge can be found in groundwater in the area due to the dumped foundry waste. The main components of the waste are foundry sand and phenolformaldehyde resin. Investigations have shown that the sludge does not affect the quality of the groundwater but, however, presents a danger for a very rare animal species. Remedial measures for the site has been proposed e.g. building of a concrete barrier around the landfill in the depth of 70-100 meter to prevent the leaking of water and spreading of waste material into the groundwater.

Information provided by Inga Turk at the Ministry of Environment and Physical Planning – Nature Protection Authority, Ljubljana Slovenia. March 26, 1999.

Information provided by Branko Druzina at the Institute of Public Health of the Republic of Slovenia. April 1999.

Ad Hoc International Working Group on Contaminated Land (1998). Papers from the International Workshop on Land Recovery and Man-Made Risks held in Vienna, November 16-18, 1998.

Act on the Protection of the Environment (1993). Official Journal of the Republic of Slovenia, No. 32/93.

Decree on the Limit, Warning and Critical Concentration Values of Dangerous Substances in Soil (1996). Official Journal of the Republic of Slovenia, No. 68/96.

Decree on Input of Dangerous Substances and Plant Nutrients into the Soil (1996). Official Journal of the Republic of Slovenia, No. 68/96.

Regulation on the Operation Monitoring of the Input of Dangerous Substances and Plant Nutrients into the Soil (1997). Official Journal RS, 55/97.

Ministry of Environment and Physical Planning - Nature Protection Authority (1998). National Environmental Action Plan (NEAP).

Ministry of Environment and Physical Planning - Nature Protection Authority (1995 and 1996). Environmental Report.

Biotechnical Faculty, Centre for Soil and Environmental Sciences (1989 and 1990). Soil Pollution map of Celje County.

Biotechnical Faculty, Centre for Soil and Environmental Sciences (1992). Soil Pollution Monitoring in Slovenia.

Economic Commission for Europe – Committee on Environmental Policy, United Nations (1997). Environmental Performance Reviews – Slovenia.

NATO/CCMS Pilot Study (1998). Evaluation of Demonstrated and Emerging Technologies for the Treatment of Contaminated Land and Groundwater (Phase III). 1998 Annual Report.

POPIN (Population Information Network) (1999). The Demography of Countries with Economies in Transition. At gopher://gopher.undp.org/00/ungophers/popin/wdtrends.

UN/ECE Statistical Division (1998). Trends in Europe and North America. 1998 Statistical Yearbook of the UN/ECE. At http://www.unece.org/stats/trend/trend_h.htm. Based on figures from 1994 – 1997.