Environmental Remediation Techniques for Soil Contamination

1. ENVIRONMENTAL REMEDIATION EAT441/3 SEM I, 2014-2015 CHAPTER 7: ENV. REMEDIATION (PART 1 Env. Remediation Technique Selection) S. Ragunathan AMPRIM, MIMM, AMESM Dip. (Public Health), B. Tech (Env), MSc. (Env. Eng), phD(Polymer Recycling) School of Environmental EngineeringUNIVERSITY MALAYSIA PERLIS

2. WHAT IS EXPECTED FROM YOU ? At the end of 2 hours lecture • List out all available Env. Remediation Techniques • Understand where and how Env. Remediation is done? • Able to select appropriate Environmental remediation method according to contaminant nature.

3. Chapter 7: Environmental Remediation • Develop methodology for environmental remediation • Site characterization, • assessment of problem, • treatment approaches, (Soil & Water) • monitoring program, • Consideration of health and safety

4. Chapter 7: Environmental Remediation Where is it done? Soil remediation techniques are applied to the vadose zone ranging from the soil rooting zone to capillary fringe. 5 common remediation techniques for How is it done currently?

5. INTRODUCTION (Soil Remediation) Where soil remediation is done? Soil remediation techniques are applied to the vadose zone and also till to saturated zone when ground water is pumped to create an unsaturated zone. • Vadose Zone (Unsaturated Zone) • A subsurface zone of soil or rock containing fluid under pressure that is less than that of the atmosphere. Pore spaces in the vadose zone are partly filled with water and partly filled with air. The vadose zone is limited by the land surface above and by the water table below. • Vadose zone divided into: • Soil water or root zone • Intermediate vadose • Capillary zone

6. INTRODUCTION (Soil Remediation) Where soil remediation is done? • Vadose zone divided into: • Soil water or root zone • Intermediate vadose • Capillary zone

7. Chapter 6: Environmental Remediation Sources of subsurface contamination (USEPA, 1990)

8. INTRODUCTION by location Remediation work is usually describes as: - ‘On-site’ activities describes work being carried out within the confines of a remediation project. - ‘Off-site’ activities are those that are carried out away from the site such as disposal of material to a landfill site or treatment centre.

9. INTRODUCTION by technique Remediation treatment is usually describes as: - In-situ remediation techniques involved leaving the soil in its original and bringing the treatment processes to the soil. - Ex-situ remediation techniques involved removing the soil from the subsurface and treat it ‘on-site’ or ‘off-site’. • In-situ remediation methods cause fever disturbances to the site, less contaminant exposure to public and less expensive than ex-situ methods.

10. INTRODUCTION by treatment technique • In situ treatment consist of treating contaminated soil in place. • In Prepared bed system, the contaminated soil may be either:- • Physically moved from its original site to a newly prepared area. • -Or removed from the site to a storage area while the original location is prepares for use and then returned to the bed, where treatment is accomplished. • In-Tank treatment involves removing the contaminated soil and treating it in a vessel or other system designed to optimize treatment efficiency.

11. INTRODUCTION (Soil Remediation) • Remediation techniques for contaminated soil: • Physical and chemical treatment • Biological treatment • Fixation/encapsulation • Thermal destruction • Physical and chemical treatment: • Soil vacuum extraction/soil vapor extraction (SVE) • Soil washing • Soil flushing • Neutralization • Oxidation • Photolysis • Precipitation • Reduction • Carbon adsorption • Ion exchange

12. INTRODUCTION (Soil Remediation) • Biological treatment: • Aerobic bioremediation • Anaerobic bioremediation • Biological seeding • Composting • Enzyme addition • Remediation techniques for contaminated soil: • Physical and chemical treatment • Biological treatment • Fixation/encapsulation • Thermal destruction • Fixation/Encapsulation treatment: • Cement solidification • Glassification/vitrification • Lime solidification • Thermoplastis microencapsulation • Thermal treatment: • Pyrolysis • Soil thermal extraction • Thermal desorption

13. INTRODUCTION (Remediation Technique selection) *In Situ treatment consist of treating contaminated soil in place. -Clay or Plastic liner is prepared to retard further transport of contaminants . *Bed treatment approach is used (Hazardous waste treatment methods on site) or *In –Tank treatment involves treatment of contaminated soil in vessel or other system design Please refer the following tables for available treatment techniques

14. INTRODUCTION (Remediation Technique selection) Physical/chemical Treatment Method Method Characteristics Limitation

15. INTRODUCTION (Remediation Technique selection) Physical/chemical Treatment Method Method Characteristics Limitation

16. INTRODUCTION (Remediation Technique selection) Physical/chemical Treatment Method

17. INTRODUCTION (Remediation Technique selection) Biological Treatment Method

18. INTRODUCTION (Remediation Technique selection) Fixation/ Encapsulation Treatment Method

19. INTRODUCTION (Remediation Technique selection) Thermal Treatment Method

20. INTRODUCTION (Remediation Technique selection) Other Treatment Methods

21. INTRODUCTION (Remediation Technique selection)

22. Chapter 6: Environmental Remediation Planning Questions to be answered in Environmental Remediation • Nature and extent of contamination – what is the contaminant and current state? • What are technical options for remediation – how do we fix it?

23. Chapter 6: Environmental Remediation Planning Contamination Happens

24. Task for next Lecture/Wishes Read about Bio-remediation methods (Thank You for being my excellent students) * Understanding is the key to knowledge and wisdom.