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Groundwater Protection in Selected Countries

5. Comparisons

5.1 Environmental pressures and resources

Table 5.1 gives some basic information about the five countries selected for this study.

Table 5.1
Basic information for the selected countries.

NA = not available * EEA, 1998

Gross Domestic Product (GDP) is a measure of a country’s production of goods and services. In general, there is a positive coupling between GDP and environmental pressures: the higher the GDP, the greater the depletion or deterioration of natural resources such as groundwater. Theoretically, a negative coupling could be envisioned since a high GDP would seem to indicate adequate welfare for stringent environmental policy. Effective strategies for the protection of groundwater resources is an example of attempts to reduce environmental pressures independently of the GDP.

Population density also has a positive coupling to environmental pressure. In recent decades, there has been a general trend towards smaller households in industrialised countries (from 3.5 to 2.6 between 1950 and 1990 in western Europe for example). This trend also increases environmental pressure since heated buildings, lighting, appliances and durable goods such as cars are shared by fewer people. Therefore, household density may be a more appropriate measure of environmental stress the population density.

In Europe, GDP and population density are relatively high and expected to increase further in the coming years. Household size is expected to continue its decreasing trend. These facts and expectations indicate that environmental pressures are of concern and will continue to be a concern in the future (EEA, 1998).

A measure of the environmental pressure is the pressure factor. This factor is defined here by the equation below in which the gross domestic product is normalised by geographical area:

Environmental resources

In general, the quantity of a country’s environmental resources is positively coupled to the area of the country. In the case of groundwater, the quantity is further coupled to the net precipitation (precipitation minus evaporation).

A measure of the groundwater resource is the resource factor. This factor is defined here by the equation below in which the amount of the groundwater resource is normalised pr. person since this resource must be shared:

Comparisons

The five countries included in this study can be compared using the very simple factors for the groundwater resource and environmental pressures defined above. The results of these calculations can be seen in table 5.2 below.

Table 5.2
Calculation of the resource and pressure factors.

According to table 5, Austria enjoys the most positive results of a relatively high resource factor and relatively low environmental pressure factor. Furthermore, the UK and Denmark are faced with the greatest challenge, having a relatively low resource factor and a relatively high environmental pressure factor.

This comparison is obviously very rough and therefore of limited value. Improvements could be made by including additional factors and by weighting the existing factors.

Even more significantly the comparison above does not take in to account the tremendous regional variations in population density, rainfall and GDP that occur within the borders of each country. An example of regional variations can be seen in the very uneven distribution of rainfall in Austria, Spain and the USA (net precipitation in Spain ranges from over 1,000 mm pr. year in the north Atlantic coastal region to <50 mm pr. year in the southern Mediterranean coastal region). Regionally, the scores shown in table 5.1 would vary considerably. The comparison above is therefore only intended to give a general backdrop of basic information for the other results in this report.

5.2 Number of contaminated sites

Information regarding the number of contaminated sites which has been obtained from the five countries in this study is not suitable for comparison. There are several reasons for this.

Numerous programmes

Firstly, some countries have a variety of programmes for remediation of point sources. For example, Denmark has at least 6 distinctive programs related to orphaned sites, currently-operating sites, petroleum industry sites, military sites, railway sites, and sites causing property value loss for home owners. A second example is that programmes exist at different levels. For example, in the United States, there are programmes at the national level as well as at the level of the 50 separate states. In this study, it was not possible to collect information on all of these numerous programmes for the individual states.

Contaminated site definition

Secondly, there are differences between the individual countries in the requirements for listing a point source as a contaminated site. Some programmes, such as the American Superfund programme, require a high ranking (only those sites with a score of 28.5 on the Hazard Ranking System scale from 0 to 100 are eligible for placement on the national priorities list) resulting in a relatively low number of sites in this programme, whereas other programs require only technical evidence of contamination (for example, chemical analysis showing elevated contaminant concentrations in a soil or groundwater sample). Unless an international agreement on the definition of a contaminated site is made, comparisons between countries will continue to be difficult.

Legal drivers for listing

In England, legal drivers which require local authorities to "cause its area to be inspected from time to time for the purpose of identifying contaminated land" are not yet implemented.

Status af listing

It is evident that most countries which do have legal drivers for identifying and listing contaminated sites are in an early phase of the work. After initially identifying 370 contaminated sites, Spain is currently carrying out a considerably more ambitious third phase of listing. Austria has identified approximately 29,000 sites out of an estimated 80,000 sites.

Voluntary clean-ups

Finally, voluntary clean-ups are important in most countries. Reporting requirements for these clean-ups can, however, be lacking.

5.3 Prioritisation of remediation

Several different things can be meant by the "prioritisation of contaminated sites". For example, contaminated sites can be prioritised according to various geographical scales such as a regional prioritisation or a national prioritisation. Point sources can also be prioritised for a specific phase of work. For example, one prioritisation could be for which sites are to be investigated first and another prioritisation could be for which sites are to remediated first.

National vs. regional

Austria is an example of a country in which prioritisation is carried out at a national level by the Federal Environment Agency. In Denmark, prioritisation was previously carried out on a national scale by the Environmental Protection Agency, but is now done individually by each regional environmental authority.

Groundwater vs. land use

Prioritising of contaminated sites with respect to groundwater protection often takes place in parallel with prioritising of contaminated sites with respect to land use. In most countries, administration and financing of these two parallel programmes are not separate. Short term land use interests are therefore weighed against long term groundwater interests. In Denmark, a proposed new soil law takes the first steps in separating these two areas. If these two areas were totally separated, it would be possible to have contaminated sites which threaten land use be prioritised and remediated according to the normal political boundaries, while groundwater could be administered according to aquifer boundaries.

Risk assessment are used

Most countries describe some type of risk assessment as the basis for prioritising which sites are to be remediated first.

Initial division into classes

There is a difference, however, in whether an geographical division of the groundwater resource into classes according to value is carried out prior to the risk assessment. In Denmark, so-called "particularly valuable water abstraction areas" have now been mapped. This enables the regional authorities to concentrate remediation efforts of sites which threaten the groundwater to these particularly valuable areas. After this initial division into two categories of sites (those within and those outside the particularly valuable areas) further prioritising of the sites within the particularly valuable water abstraction areas can take place.

5.4 Financing the remediation of point sources

Polluter pays principle

The polluter pays principle is cherished by western countries. It was stated in the European Council Recommendation 75/436 on cost allocation and action by public authorities on environmental matters as well as the Environmental Protection Act of 1991. The principle is now incorporated in Article 130 of the Treaty of Rome. An example of partial use of the polluter pays principle is the Superfund programme in the USA. Here, about 70% of the programme costs are recovered from the polluters.

Barriers

Difficulties in implementing the polluter pays principle can arise as is seen by the Superfund example above. A number of barriers occur, which can make it difficult to place liability on the polluters. These barriers are listed below:

In some cases, it may not be technically possible to determine who the polluter is. In England, the source, pathway and target of contamination are said to be linked. If no linkage can be established, then there is not adequate technical evidence for determining liability.

In other cases, it may not be possible to show that the polluter has been negligent. In order to be held liable, the polluter must have known or, at the least, should have know, that his activities would cause pollution at the time of the event.

In many cases, the polluting entity may no longer exist.

In other cases, the polluting entity may not have the financial resources to remediate.

Finally, statutes of limitations mean that recovering costs from polluters in cases where the polluting activity has ceased many years prior is not legal.

Financing through taxes

Due to these reasons, a need arises to finance remediations from other sources. Various methods have been used by the five countries in this study. The Capital Projects Scheme in England is financed from the central pot of taxes. The 30% of the Superfund programme in the USA which is not financed by the polluters, is obtained through a specific tax on the chemical and petroleum industries.

Buyer beware

A final possibility for a source of funds is from the landowners of contaminated sites. In England, for example, the buyer beware principle is in effect, so that one speaks of "problem holders" rather than polluters. According to Part IIA of the Environment Act of 1995, problem holders can be held responsible for remediations if no appropriate person who caused or knowingly permitted contamination to occur can be found. In Denmark, the Lost Value Act allows for homeowners who have unknowingly purchased a contaminated site to finance the first 5,400 EUR, while the remaining expenses are covered by the state.

5.5 Water source and use

A comparison of the water supply sources used in the five countries included in this study are shown in figure 5.1. As can be seen, there are large differences in the reliance on groundwater as a supply source from one country to another. Neither Austria nor Denmark have significant reliance on surface waters.

Figure 5.1
Sources of water supply in percent (see appendixes and EEA, 1998).

It is important to realise, that this graph only illustrates the present reliance on the groundwater resource. There are presumably differences in whether this reliance is mandatory, or whether this water supply could be used without incurring undo expense. Most major cities (like London and Vienna) are situated on a major rivers, while Copenhagen has limited surface water sources in the vicinity. In Spain, aqueducts were necessary in Roman times to transport surface water long distances.

There are also large differences in the use categories from country to country. Figure 5.2 gives an overview of these uses.

Figure 5.2
Water consumption categories in percent (see appendixes and EEA, 1998).

As with contaminated sites, these numbers are difficult to compare, due to differences in which water uses are included. For example, the numbers shown for industrial water use in England do not include cooling water, which often is the major part of industrial use. The numbers for agricultural water use in England do not include fisheries.

As expected, a large percent of water consumption in Spain and the USA (mainly the western states) is for agriculture. Despite a relatively high rainfall, Denmark also uses a significant percent of water for irrigation, due to the intensity of agricultural practices. The amount of water actually used for drinking is relatively small.

In order to obtain a sustainable water policy, levels of consumption must be controlled and the groundwater resource must be protected.

5.6 Treatment of groundwater

In general, the methods used to treat groundwater for drinking water purposes are limited to aeration, filtration and disinfection. In the case of Austria, much of the spring water has low enough content of iron to make aeration and filtration unnecessary. In Austria and Denmark, disinfection is very seldom used.

In no countries are advanced methods such as stripping, carbon filtration or reverse osmosis in general use for the treatment of groundwater. For the treatment of surface waters, however, advanced methods are in more general use.

5.7 Milestone status

When comparing the five countries in this study, major differences can be seen in the progress made in relation to various milestones. An extreme example is the listing of sites. In England, where legal drivers requiring local authorities to list contaminated sites in not yet implemented, no official list yet exists. In Denmark, over 90% of the estimated total of contaminated sites has already been listed (EEA, 1998).

An interesting point to note is the sharing of technical know-how. If one country carries out a research and development programme, results are often used immediately in other countries. In this way, countries can benefit from the fact that other countries have reached a technical milestone.

The internet is a very fast and efficient method of transfer of know-how. Of the five countries in this study, the USA was superior in the amount and relevance of information made available on the internet. A systematic international method for transfer of relevant data would be advantageous.

5.8 Methods for groundwater protection

In all of the five countries studied, implementation of groundwater protection initiatives is carried out on various scales, ranging from areas in the immediate vicinity of individual well fields to areas on the scale of an entire country, which can supply overviews. Table 5.3 gives an overview of some of the various initiatives of the five countries.

Table 5.3
Overviewof the groundwater protection initiatives of the five countries.

Well field initiatives

As can be seen by the overview, all countries with the exception of Spain have initiatives in relation to individual wells. Often, these mention the risk of bacterial contamination as a motivating factor for defining circular well field protection zones. England notes that these zones are not necessarily used for abstractions in confined aquifers.

Two similar methods for determining the radius of the circular zones are used: a specific distance and a specific travel time. Neither of these methods involves a high data requirements and are therefore practicable. The travel time method simple requires an estimate of the permeability and groundwater gradient of the aquifer.

The area of these zones is relatively limited. This means that the cost of implementing various protection measures (including remediation of contaminated sites) is economically manageable.

Resource initiatives

At the other end of the scale, there are also initiatives on the scale of an entire country. These are generally related to one or both of the following aspects of the groundwater resource; aquifer value or aquifer vulnerability.

In the Danish example, mapping of particularly valuable water abstraction areas has just recently been completed. As the name indicates, this mapping is based on aquifer value as it relates to population density and on the current water supply structure, such that there is focus on aquifers in current use. In the English example, a combination of potential yield and vulnerability have been used to prepare maps on a scale of 1:100,000. These maps are now complete for all of England And Wales.

These overview initiatives are tools which can be used for prioritising remediation of contaminated sites, local planning, etc.

Recharge area initiatives

The middle column in table 5.3 involves initiatives on the scale of recharge areas for individual wells or well fields. This type of initiative is perhaps the most challenging for two reasons.

Firstly, data requirements for determining recharge areas are great. Often, water level measurements must be collected from the field, pump test data evaluated and groundwater modelling carried out. For this reason, England notes that source catchment areas will be defined only for the larger water supplies. Secondly, since the areas here are large (compared to well field zones), protection initiatives such as remediation can be very expensive. Therefore, there is a need to further divide these areas into sub-areas. One example of this subdivision is to use aquifer vulnerability, which in turn requires yet more data.

These recharge area initiatives are not completed yet in any country. In Denmark, a guidance document for detailed zoning of recharge areas is under preparation. After designation especially vulnerable areas, the document has provisions for direct protection measures such as limitations of farming practices as well as indirect measures such as future land use planning.

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