Environmental screening method for dredging in contaminated river

Applied Mechanics and Materials Vol. 567 (2014) pp 50-55 Online available since 2014/Jun/06 at www.scient$c.net O (2014) Trans Tech Publications, Switzerland doi:I 0.4028/www.scientific.net/AMM.567.567.50

Environmental Screening Method for Dredging in Contaminated River

MANAP,

~orpadzlihatun'~~

and VOULVOULIS, ~ i k o l a o s * ~ ~

'~epartment of Construction Management, Faculty of Technology and Business, 86400 Parit Raja, Batupahat, Johor, Malaysia

'Centre for Environmental Policy, 151 5, 15 Prince's Gardens, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom

Keywords: Dredging, Risk management, Environmental screening, Contaminated sediments, Ecological Risk Assessment

Abstract. Dredging in a contaminated river has been widely accepted to have an impact on the environment; however environmental risk assessment analysis could be costly, time-consuming and difficult to perform. Therefore, a screening method acting as a preliminary risk assessment analysis to screen potential contaminated areas is necessary. The aim of this study is to demonstrate a new screening method for risk assessment analysis in a scenario where economy, time and simplicity factors had been a concern. The development of this method is based on a variation of standard Ecological Risk Assessment. An analysis will be performed on two elements. Firstly, the level of contaminants in the water, groundwater and air (known as the media) and, secondly the behavior of environmental indicators during monitoring of historical dredging. This analysis is performed in order to establish the degree of contamination in an area that is about to be dredged, in where the publicly accessible contamination level in the media and the historical dredging monitoring data will be utilized. Eight dredged sites in Peninsular Malaysia are selected as the case studies of this research. This research showed that Sungai Perlis has a very high total risk value, which could have a fatal impact on its biodiversity if dredging is performed with negligence at this location. This research could provide an opportunity for Malaysia to increase its efforts to avoid dredging impacts without being constrained on time, cost and simplicity factors.

Introduction

Dredging, which is performed in a highly contaminated site but has not been identified as a risk, could prove fatal for biological resources. Such cases have been observed in the developing country of Malaysia [I-41. This could be due to current understanding of low number of contaminated sites owing to its slower development rate in comparison to countries like the US and the UK, in that their contaminated land requires strict environmental rules and regulations [4]. Moreover, it has been generally accepted that assessing environmental risks and providing mitigation measures is costly [5-71, which is a discouraging factor for many developing countries to use the already developed tools and assessments. In fact, a research which explored dredging issues in the developing country of Malaysia, confirmed that it lacks efficient tools and practices to assess the environmental risks of dredging [8]. Therefore, the need remains for an efficient tool or assessment, which takes into account a country's economic capability, to be developed in order to identify possible risks of dredging.

Ecological Risk Assessment (ERA) has been widely used to assess impacts of chemical exposure on endangered biological resources [9-111. This analysis involves simplistic phases of risk assessment and three phases of ERA have been suggested by the United States Environmental Protection Agency (US EPA) (1998) namely: problem formulation, extent of impacts from exposure to chemicals over toxicity levels, and characterization of risk [lo, 121.

54 Structural, Environmental, Coastal and Offshore Engineering

This screening method enables the accurate initial prediction of environmental dredging 'risks and it is straightforward and efficient in terms of time and cost. This could encourage parties that stress upon benefits in cost, simplicity and time, like Malaysia, to take proactive actions toward protecting their environment, whilst increasing their economic strength.

Conclusion

Dredging has been proven to have an impact on the environment and many tools and assessments have been developed. However these are difficult to perform, costly and time- consuming. This study demonstrated a newly developed screening method for the environmental risks of dredging, using publicly accessible data and available historical dredging monitoring data in its variation of ERA phases suggested by US EPA (1998). This method was demonstrated in a scenario of a developing country, Malaysia, where economic impact has always been a concern. It has been found that Sungai Perlis has the highest value of total historical dredging risk, whereas Sungai Muar is the location with the highest value of total media risk. The analysis of total risk value (addition of total historical risk value and total media risk value) found that Sungai Perlis has

a very high degree of total risk value. This indicates that the level of contamination at Sungai Perlis is categorized as very high. However, this result is arguable due to the fact that it was not possible to retrieve groundwater data prior the execution of this study. Nevertheless, this research highlighted the many insufficiencies of environmental monitoring in this country, where this method could provide an opportunity to improve current efforts to prevent environmental damage due to dredging. This improvement should be reflected in future dredging projects, when this method is used, in order to benefit from its low cost, time efficiency and straightforwardness.

Acknowledgment

This research performed to fulfill the requirement of Short Term Research grant and acknowledgments are given to the Office for Research, Innovation, Commercialization and Consultancy Management (ORICC), Universiti Tun Hussein Onn Malaysia for all their support during the publication of this paper.

References

[I] S. Su, Potential Long-Term Ecological Impacts Caused by Disturbance of Contaminated Sediments:A Case Study, Environ.Manage. 29 (2002), pp. 234-249.

[2] R. Guerra, A. Pasteris and M. Ponti, Impacts of Maintenance Channel Dredging in a Northern Adriatic Coastal Lagoon. I: Effects on Sediment Properties, Contamination and Toxicity, Estuar.Coast.Shelf Sci. 85 (2009), pp. 134-142.

[3] A. Toes, Effects of Deposition of Heavy-Metal-Polluted Harbor Mud on Microbial Diversity and Metal Resistance in Sandy Marine Sediments, Arch.Environ.Contam.Toxico1. 55 (2008), pp. 372-385.

[4] C.Y. Yi and A.S. Talib, Overview of Brownfields in Malaysia, Jurutera. April (2006), pp. 16-23. 151 D.J. Morrisey, Environmental Impact assessment-A Review of its A i m and Recent Developments, Mar.Pollut.Bull.26 (1993), pp. 540-545.

[6] J. Burton G-Allen, Sediment Quality Criteria in use Around the World, Lirnnology. 3 (2002), pp. 65-76.

[7] R.B. Choueri, A. Cesar, D.M.S. Abessa, R.J. Torres, I. Riba, R.D. Morais, A.A. Mozeto and T.A. DelValls, Harinonised Framework for Ecological Risk Assessment of Sediments from Ports and Estuarine Zones of North and South Atlantic., Ecotoxicology. 19 (2010), pp. 678-696.

Applied Mechanics and Materials Vol. 567 55

[9] H. Pekey, D. Karaka~, S. Ayberk, L. Tolun and M. Bakofjlu, Ecological Risk Assessment using

Trace Elements from Sulface Sediments of Izmit Bay (Northeastern Marmara Sea) Turkey,

Mar.Pollut.Bull.48 (2004), pp. 946-953.

[lo] U.S. Environmental Protection Agency, Guidelines for Ecological Risk Assessment (1998). [ l l ] H. Pekey, D. Karakq, S. Ayberk, L. Tolun and M. Bakofjlu, Ecological Risk Assessment using

Trace Elements from Sulface Sediments of Izmit Bay (Northeastern Marmara Sea) Turkey,

Mar.Poll~t.Bull.48 (2004), pp. 946-953.

[12] National Research Council, Risk Assessment in the Federal Government: Managing the

Process, National Academy Press, Washington, D.C., 1983.

[13] Y. Perrodin, M. Babut, J. Bedell, M. Bray, B. Clement, C. Delolme, A. Devaux, C. Durrieu, J. Gamc and B. Montuelle, Assessment of Ecotoxicological Risks Related to Depositing Dredged

Materialsfrom Canals in Northern France on Soil, Environ.Int. 32 (2006), pp. 804-814.

1141 S. Ware, S.G. Bolam and H.L. Rees, Impact and Recovery Associated with the Deposition of Capital Dredgings at

UK

Mar.P0ll~t.B~ll.60 (2010), pp. 79-90.

[15] S. Piou, Changes in the Geochemistry and Ecotoxicity of a Zn and Cd Contaminated Dredged

Sediment Over Time A f e r Land Disposal, Environ.Res. 109 (2009), pp. 712-720.

[16] M. Munawar, In Situ Bioassessment of Dredging and Disposal Activities in a Contaminated

Ecosystem: Toronto Harbour, Hydrobiologia. 188-1 89 (1989), pp. 601-618.

[17] B. Moss, J. Madgwick and G. Phillips, A Guide to the Restoration of Nutrient-Enriched

Shallow Lakes, W W Hawes, United Kingdom, 1996.

[18] C.K. Jain and D. Ram, Adsorption of Metal Ions on Bed Sediments / Adsorption d'lons M6talliques Sur Les Skdiments De Fond, Hydrological Sciences Journal. 42 (1997), pp. 713.

[19] M. De Nobili, R. Francavigha and P. Sequi, Retention and Mobility of Chemicals in Soil, in

Developments in Soil Science Vol. Volume 28, Part 1, A. Violante, P.M. Huang,J.-M.Bollag and L.Gianfreda, ed., Elsevier, 2002, pp. 17 1-196.

[20] M. Department of Environment, Environmental Quality Report 2006 - 2011, Annual

Environmental Quality Report of Malaysia (2006), pp. 1-78.

1211 M. Department of Environment, Environmental Quality Report 2007, Annual Environmental Quality Report of Malaysia (2007), pp. 1-78.

Structural, Environmental, Coastal and Offshore Engjneering

10.4028/www.scientific~net/AMM.567

Environmental Screening Method for Dredging in Contaminated River