Environmental Remediation Planning Process

1. ENVIRONMENTAL REMEDIATION EAT441/3 SEM I, 2013-2014 CHAPTER 6: ENV. REMEDIATION PLANNING (Subject requirements & assessment) Dr. S. Ragunathan AMPRIM, MIMM, MESM Dip. (Public Health), B. Tech (Env), MSc. (Env. Eng), phD(Polymer Recycling) School of Environmental EngineeringUNIVERSITY MALAYSIA PERLIS

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

3. Chapter 6: Environmental Remediation Planning • Develop methodology for environmental remediation • Site characterization, • assessment of problem, • treatment approaches, • monitoring program, • Consideration of health and safety

4. Chapter 6: Environmental Remediation Planning Common contaminants founds at contaminated sites

5. Chapter 6: Environmental Remediation Planning Table (continued)

6. Chapter 6: Environmental Remediation Planning Contamination Happens

7. Chapter 6: Environmental Remediation Planning Contaminated site characterization • Site characterization will required data related to • Geology (Soil) • Hydrogeology (Water) • Contamination information (Nature of Cont.)

8. Chapter 6: Environmental Remediation Planning Questions to be answered by site characterization • Nature and extent of contamination – where is it? • What is future migration and control – where is it going? • What are receptors and their risk – what harm will it do? • What are technical options for remediation – how do we fix it?

9. Chapter 6: Environmental Remediation Planning • Site characterization data are necessary to: • Describe the occurrence and movement of contaminants at the site • Assess the background concentrations in the soil and water for the purpose of describing their precontamination conditions • Determine the impact of contamination on the subsurface • Evaluate the risk posed by the contamination on public and environment • Predicts future contaminants trends • Design of remediation methods • Monitoring program to verify the effectiveness of the site remediation technology

10. Chapter 6: Environmental Remediation Planning Site characterization methodology

11. Chapter 6: Environmental Remediation Planning Purpose and Work Plan Phase I Phase II Preliminary Assessment Phase III Report Preparation Phase IV Site Characterization Complete

12. Chapter 6: Environmental Remediation Planning Preliminary site assessment • Crucial step • Provides geographical location, site background, hydrological information and sources of contaminants • Literature review • Site visit

13. Chapter 6: Environmental Remediation Planning Literature review • Site records • Interviews • Site permits • Geological maps and reports • Water well logs and records • Topographic maps • Aerial photos • Soil survey maps • Other sources

14. Chapter 6: Environmental Remediation Planning Site visit • To observe and record potentially important surface features • Any suspected objects • Samples • Sampling, labeling and handling • Test for chemical composition and suspected contaminants

15. Chapter 6: Environmental Remediation Planning Site visit

16. Chapter 6: Environmental Remediation Planning Phase II Purpose and Work Plan Phase I Exploratory Site Investigation Phase III Phase IV Report Preparation Site Characterization Complete

17. Chapter 6: Environmental Remediation Planning Exploratory site investigation • Purpose and scope of exploratory field investigation • Important to obtain preliminary site-specific data • Design detail site investigation program

18. Chapter 6: Environmental Remediation Planning Stages of investigation • Stage 1 – scoping study Is there a problem? How bad is it? • Stage 2 – prepare field study plan Includes sampling and analysis, health and safety,and quality assurance plans • Stage 3 – conduct on-site sampling and analysis • Stage 4 – interpretation, assessment, modeling(Stages 3 and 4 may be iterative) • Stage 5 – design remedial action

19. Chapter 6: Environmental Remediation Planning Purpose and Work Plan Phase III Phase I Detail Site Investigation Phase II Phase IV Report Preparation Site Characterization Complete

20. Chapter 6: Environmental Remediation Planning Detail Site Investigation • Characterize the geology and hydrology of the site • Data must be adequate to assess the fate and transport of the contamination • To design an optimal remedial system • Take a few weeks to few years to complete with a variety of techniques to characterize the site geology, site hydrology and site contamination

21. Chapter 6: Environmental Remediation Planning Methods of Obtaining Soil and Rock Data • Direct Methods • Geophysical Methods • Drive methods

22. Chapter 6: Environmental Remediation Planning Direct methods

23. Chapter 6: Environmental Remediation Planning Direct Methods

24. Chapter 6: Environmental Remediation Planning Direct Methods

25. Chapter 6: Environmental Remediation Planning Direct Methods

26. Chapter 6: Environmental Remediation Planning Diamond drilling

27. Chapter 6: Environmental Remediation Planning Question Discuss the source of literature review for site characterization of an old landfill. What method will you suggest for obtaining soil data from a petrochemical plant...Discuss the advantages and the disadvantages of the selected method.

28. Chapter 6: Environmental Remediation Planning Geophysical method Geophysical method • Define site geology are useful in reducing costs when investigating large sites • Also used in preliminary investigations and provide verification of direct method results • Interpretation of direct method is difficult and requires special expertise • Two categories (1) borehole geophysical methods and (2) surface geophysical method

29. Chapter 6: Environmental Remediation Planning • Borehole geophysical methods • A probe is lowered into borehole using a cable • Probe transmit signals to surface instruments that generate logs or charts • 3 categories (1) electrical/electromagnetic methods which measure resistivity and conductivity of fluids and surrounding rocks (2) nuclear methods which use natural or artificial sources of radiation and radiation detectors to characterize rock and fluid properties and (3) acoustic/seismic methods, which measure the elastic response of subsurface rock to seismic sources • Selection of particular type depend on the type of borehole (cased or uncased) and whether it is filled with fluid or is dry

30. Chapter 6: Environmental Remediation Planning • Borehole geophysical methods • A probe is lowered into borehole using a cable • Probe transmit signals to surface instruments that generate logs or charts • 3 categories (1) electrical/electromagnetic methods which measure resistivity and conductivity of fluids and surrounding rocks (2) nuclear methods which use natural or artificial sources of radiation and radiation detectors to characterize rock and fluid properties and (3) acoustic/seismic methods, which measure the elastic response of subsurface rock to seismic sources • Selection of particular type depend on the type of borehole (cased or uncased) and whether it is filled with fluid or is dry

31. Chapter 6: Environmental Remediation Planning • Drive methods • Most common drive method is cone penetrometry • A cone shaped instrument is pushed into the soil hydraulically and the resistance to penetration is measured • The resistance is measured by sensitive strain gauges that transmit electronic data to the acquisition system • Resistances measured are correlated with different soil types • Useful in initial site characterization • Must be calibrated with properties obtained from drilling and sampling data for the site

32. Chapter 6: Environmental Remediation Planning Methods of obtaining chemical data • Characterization of site geology and hydrology, as well as characterization of the type and extent of contamination • Soil in vadose and saturated zones, and groundwater

33. Chapter 6: Environmental Remediation Planning Sampling procedure • The quantity of sample and method of preservation depends on the type of analyses to be performed. • Physical appearance of the water – colour, turbidity, odour, and its pH, conductivity and temperature were measured. • Once water stabilized, sample are collected in prelabeled containers and stored on ice for transportation to a laboratory. • Method ??

34. Chapter 6: Environmental Remediation Planning Decontamination procedures • All equipment that comes into contact with soil samples should be decontaminated before use and between sampling points. • Can be accomplished by directing high pressure hot wash water over outside and inside surfaces of the equipment. • Pressurized spray may be used to apply a 50/50 mixture of acetone and distilled water. • The mixture is rinsed by directing a high pressure hot water wash over the equipment. • Allow the equipment to air dry.

35. Chapter 6: Environmental Remediation Planning • All equipment contacts with groundwater (water level indicator, bailer, funnels) should washed in an Alconox or similar solution. • Rinsed by distilled/deionized water. • Mixture of acetone and distilled water is applied after rinsing. • Mixture is rinsed with distilled water/deinized water. • Fragile equipment such as pH meter, conductivity meter and thermometer should be rinsed in distilled water between sample measurement.

36. Chapter 6: Environmental Remediation Planning QA/QC samples • To be used in the field for sampling of soil and groundwater. • Includes collecting field blanks and trip blanks • Field blanks – samples that are obtained by running analysis free deionized water through sample collection equipment (bailer, pump, auger, spatula) after decontamination. • Placed in appropriate sample container for analysis. • To determine the sufficiency of decontamination procedures.

37. Chapter 6: Environmental Remediation Planning QA/QC samples cont. • Trip blanks are prepared prior to the sampling event in the actual sample container • Kept with the investigative samples throughout the sampling event. • Then packaged for shipment with the other samples and sent for analysis. • Collection frequency of QA/QC is specified for each sample medium. • Frequency based on estimated number of samples to be collected. • May vary depending on the actual number of collected.

38. Chapter 6: Environmental Remediation Planning Chain of custody procedures • Samples for analysis should always be shipped in sealed coolers and containers. • Each container should be affixed with a numbered of chain of custody seal • A proper completed chain of custody form must accompany the samples. • A chain of custody should include information on well number or sample location number, name and signature of each person who has transported or received the samples, name and signature of person who has transported or received the samples, collect the samples, an inventory of all sample bottles and container in the shipping container

39. Chapter 6: Environmental Remediation Planning Chemical analysis • Testing on soil and groundwater samples should be performed in accordance with USEPA test procedures or applicable ASTM test methods. • Laboratory test methods to analyze soil and groundwater samples ?? • Some test may be performed in the field using portable or mobile equipment.

40. Chapter 6: Environmental Remediation Planning Data analysis and evaluation • Geologic, hydrologic and chemical data should be assembled in proper form. • Used to define the extent of contamination. • Geologic data – detailed logs should be prepared for each boring/sampling location. Log should document location, drilling and sampling methods, description of soil layer and all laboratory and field test result. • Hydrologic data – summary of piezometer and monitoring well location, and their built as-built diagrams should be prepared. • The in-situ hydraulic conductivity test should be analyzed to calculate the hydrologic properties of different geologic units.

41. Chapter 6: Environmental Remediation Planning • Chemical data – the validity of the data based on QA/QC procedures • Chemical data used to define the background chemical concentration levels and to define the boundary of contaminated area. • Report preparation – overall geologic, hydrologic and contaminant data are reviewed to recognized the consistent pattern. • Prepared at the completion of site characterization process, documenting the investigation procedures and result.

42. Chapter 6: Environmental Remediation Planning Risk assessment • Data collection and evaluation • To identify potential chemicals concern • Identify contaminant identities • Identify contaminant concentration in the key sour source and media of interest • The characteristics of the source contamination • The characteristics of environmental setting

43. Chapter 6: Environmental Remediation Planning Risk assessment • Exposure assessment • Estimating the type and magnitude of human exposure to the selected chemicals of potential concern • Characterization of exposure setting • Identification of exposure pathways • Quantification of exposure concentration

44. Chapter 6: Environmental Remediation Planning Risk assessment • Toxicity assessment • Identification of potential adverse health effects of a contaminant • Review of toxicology data derived from epidemiological study • Risk characterization • Combines the exposure and toxicity assessments into quantitative and qualitative expressions of risk • Task 1 – organize results of exposure and toxicity assessments • Task2 – quantify pathway risk • Task 3 – combine risks across exposure pathways • Task 4 – assess and present uncertainty

45. Chapter 6: Environmental Remediation Planning Risk assessment Task 1 – Organize results of exposure and toxicity assessments  Task 2 – Quantify pathways risks Individual noncarcinogens, the noncancer hazard quotient (HQ) is calculated for non cancerous health effects HQ = E RfD E = exposure level obtained from exposure assessments RfD = reference dose obtained from the toxicity assessment for the same exposure pathway

46. Chapter 6: Environmental Remediation Planning Risk assessment Task 3 – Combine risks across exposure pathways Sum the risks across exposure pathways to calculate total risks Reasonable exposure pathways were identified The likelihood of the same person facing exposure by more than one path is determined Task 4 – Assess and Present uncertainty Associated with the selection of chemicals of concerns and their concentrations, toxicity values, site-related variables and assumptions in exposure assessment should be determined and clearly presented

47. Chapter 6: Environmental Remediation Planning Risk assessment • Final results of baseline risk assessment includes estimated cancer and noncancer risks for all exposed pathways and landuse for all chemicals of concerns • Hazard Index (HI) > 1 , adverse health effects of the chemicals are inferred • Cancer risk greater than 10-6 (one in a million) is unacceptable

48. Chapter 6: Environmental Remediation Planning Remedial strategy to address site contamination by using a flowchart.

49. Chapter 6: Environmental Remediation Planning • 1. First option is natural attenuation is used when there is a potential for the contaminants mainly organic chemical, to be degraded by naturally occurred microorganisms. • 2. Instead of landfill and surface impoundments, many opt to leave the contaminated media in subsurface and constituent in-situ barriers to enclose contaminated zone. Two systems ‘Passive Systems’ and ‘Active Systems’ can be used • 3. Remedial methods aim at extra-activity, immobilizing, destroying or detoxifying the contaminants in soils and groundwater. Divided into two categories, in-situ and ex-situ • 4. In-situ treats contaminated soil and/or groundwater in place. Ex-situ treats excavated contaminated soils and/or groundwater at offsite.

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