Styrkor och svagheter hos gällande styrmedel för avloppsslam
Author
Summary, in English
The criticism towards agricultural use of sewage sludge tends to occur in ten year cycles; the debate has begun once more. The aim of this study is to evaluate current policy for agricultural use of sewage sludge, by investigating how pollutants within the sludge are affected. Two types of substances; a heavy metal (cadmium) and an organic substance(nonylphenol), are used to illustrate possible strengths and weaknesses. The overall objective is to contribute to the ongoing debate about the use of sewage sludge. The legislation does not contribute to a reduction of pollutants in sewage sludge, as there is a lack of incentives for agricultural use. If the sewage sludge contains high levels of a regulated pollutant it can be used for alternative purposes. Instead, the legislation influences the dispersion patterns. Sewage sludge with the lowest levels of pollutants are used on arable land. Sewage sludge with higher levels of pollutants is disposed of within other land uses. As a result, the risk of negative effects on arable land and towards humans is reduced. Although, the sewage sludge with higher levels of pollutants are still being used, thus causing negative effects to the environment as a whole.
The study illustrates that current levels of cadmium and nonylphenol in the environment are problematic, and the exposure to humans and nature must be reduced. Hence, the only way to avoid negative effects on human health and the environment when using sewage sludge is to reduce its overall content of pollutants.
In addition, the study shows that the most effective way to further reduce the prevalence of cadmium and nonylphenol in sewage sludge is through stricter regulation in other areas, e.g. gas purification or the ban of a specific substance use in products. However, the implementation of tricter regulations has been problematic within Sweden. The overall assessment is therefore that the certification scheme called REVAQ is the best available method to further reduce the concentration of pollutants in sewage sludge. The aim with REVAQ is to reduce the amount of heavy metals and organic pollutants, through structured working methods at the waste water treatment plants. Since REVAQ will contribute to a reduction of the concentrations of pollutants, both the dispersion and the negative effects will be reduced too. REVAQ can therefore be used as an effective tool towards reaching ‘A Non-Toxic Environment’; one of sixteen environmental quality objectives set up by the SwedishGovernment. The recommendation of this paper is to give support to the waste water treatment plants and their work with REVAQ.
The study illustrates that current levels of cadmium and nonylphenol in the environment are problematic, and the exposure to humans and nature must be reduced. Hence, the only way to avoid negative effects on human health and the environment when using sewage sludge is to reduce its overall content of pollutants.
In addition, the study shows that the most effective way to further reduce the prevalence of cadmium and nonylphenol in sewage sludge is through stricter regulation in other areas, e.g. gas purification or the ban of a specific substance use in products. However, the implementation of tricter regulations has been problematic within Sweden. The overall assessment is therefore that the certification scheme called REVAQ is the best available method to further reduce the concentration of pollutants in sewage sludge. The aim with REVAQ is to reduce the amount of heavy metals and organic pollutants, through structured working methods at the waste water treatment plants. Since REVAQ will contribute to a reduction of the concentrations of pollutants, both the dispersion and the negative effects will be reduced too. REVAQ can therefore be used as an effective tool towards reaching ‘A Non-Toxic Environment’; one of sixteen environmental quality objectives set up by the SwedishGovernment. The recommendation of this paper is to give support to the waste water treatment plants and their work with REVAQ.
Department/s
- Studies in Environmental Science
Publishing year
2012
Language
Swedish
Full text
Document type
Student publication for Bachelor's degree
Topic
- Earth and Environmental Sciences
Supervisor
- Karin Jönsson
Scientific presentation