Bioremediation Technology for the Bioremediation Technology for the Remediation of Persistent Organic Remediation of Persistent Organic

Pollutants (POPs): Toxaphene & Pollutants (POPs): Toxaphene & Dichlorodiphenyltrichloroethane Dichlorodiphenyltrichloroethane

(DDT)(DDT)

Siti Jariani Mohd Jani

SWS 6262 : Soil Contamination &

Remediation

OutlineOutline

Contaminated Site HistoryContaminated Site History

Site InformationSite Information

Site Information (cont.)Site Information (cont.)

EPA Superfund Record of Decision, 1985 (EPA/ROD/R08-85/003)

Contaminated SiteContaminated Site

EPA Superfund Record of Decision, 1985 (EPA/ROD/R08-85/003)

Contamination at each Contamination at each MediumMedium

Medium/characteristic DescriptionsSoil:

Pesticide contamination discovered at different depth from soil boring of installed monitor well

MW3: toxaphene (12ppm) – Upper 10 feet

RSO-8: total pesticide level of 35.12 ppm (60% is toxaphene) – 10 feet

RSO-10: total pesticide level of 4 ppm at 10-30 feet (toxephene the only contaminants to exceed 1 ppm)

Sediments In 1984 & 1985: on and off-site in sample of drainage ditch sediments.

Groundwater July 1984: total pollutants concentration of 0.06-0.2 ug/L – in 2 of 5 monitored wells.

November 1984: No concentration of pollutants was found.

Surface water 1979: DDT, highest concentrations at 25.3 ug/L

EPA Superfund Record of Decision, 1985 (EPA/ROD/R08-85/003)

ContaminantsContaminantsPOPs Toxaphene DDT

Chemical Structure

Characteristic

InsecticidePersistent in the environment and can be transported in the environment over very long distances. T1/2: 100days -12 years

Insecticide: kill weeds and vector-borne diseases like typhus and malariaPersistency leads to bioaccumulate and biomagnification effect on organisms in the environment.T1/2: 2-15 years

Toxicity Probable human carcinogen (USEPA

possibly carcinogen to humans (USEPA

Maximum clean up level (MCL)

Drinking water: 0.003mg/LMaximum contaminant level goal: 0

Drinking water: 0.007mg/LMaximum contaminant level goal: 0.007mg/L

ASTDR, 2010

Applied TechnologyApplied TechnologyExcavation Incineration

Removal of 250 cubic yards (cy) to EPA permitted incineration facilities.> 100 ppm total pesticides.

Ex-situ incineration at EPA permitted facilities: The excavated materials burned in a furnace designed for burning hazardous materials in a combustion chamber at high temperatures

1) Excavated using backhoes and excavator track hoes.

2) Loaded into trucks. Total of 2500 loaded truck.

3) Sent for incineration 4) The soil was covered with tarps5) Excavation is complete when test results

show that the remaining soil around the hole meets established cleanup levels.

1) Large rocks and debris and excess water was removed.

2) The materials are then placed in the combustion chamber

3) heated to an extremely high temperature for a specified period of time.

Excavated area filled with clean soil. After an excavation was filled in, the area was covered with landscaped

How long? Start in May 1986 and remediation completed in 1992

Total Cost : $2,471,000

EPA Superfund Record of Decision, 1985 (EPA/ROD/R08-85/003)

(USEPA)

Applicable TechnologyApplicable TechnologyRemediation Technology Description

Thermal desorption clean up soil that is contaminated with VOCs and SVOCs at depths shallow enough to reach through excavation. Faster and provide better cleanup than other methods, particularly at sites that have high concentrations of contaminants. Thermal desorption is being used or has been selected for use at over 70 Superfund sites across the country.

Thermal chemical degradation : Gas phase

Chemical reduction (GPCR)

GPCR is a thermal-chemical degradation technology that combines high temperature and hydrogen gas to treat POPs. Based on available information, the technology has treated DDT, HCB, PCBs and dioxin in contaminated soil, sediments, and liquids. Due to the high temperature requirement of this technology, GPCR could potentially treat other POPs.

Physical-chemical treatment

Physical-chemical treatment includes soil vapor extraction, solidification/stabilization, soil flushing, chemical oxidation, and electrokinetic separation.

Bioremediation Using natural microorganism (such as bacteria, Fungi, biopolymers) and plants (phytoremediation) to degrade hazardous organic contaminants or convert hazardous inorganic contaminants to environmentally less toxic or nontoxic compounds of safe levels in soils, subsurface materials, water, sludges, and residues.

Phytoremediation Uses plants to clean up contaminated environments. Can clean up many types of contaminants including metals, pesticides, explosives, and oil. However, they work best where contaminant levels are low because high concentrations may limit plant growth and take too long to clean up. Plants also help prevent wind, rain, and groundwater flow from carrying contaminants away from the site to surrounding areas or deeper underground.

USEPA

Recommended TechnologyRecommended Technology

(Allen et. al., 2002 and EPA, 2007)

(Iowa State University)

Soil : Anaerobic Bioremediation of Soil : Anaerobic Bioremediation of Toxaphene using Blood MealToxaphene using Blood Meal

Materials & MethodsMaterials & Methods

ProceduresProcedures

Performance DataPerformance Data

Sources: Allen et al., 2002 and US EPA, 2007.

Notes: cy = cubic yardmg/kg = Milligram per

kilogram

Surface water: Phytoremediation Surface water: Phytoremediation of DDT using aquatic plantsof DDT using aquatic plants

Remediation PlantRemediation Plant

Ceratophyllum demersum(coontail, hornwort)

Elodea canadensis (American elodea, Canadian pondweed)

Lemna minor (common duckweed)

Performance Data: Concentration Performance Data: Concentration of pollutants remain after 16daysof pollutants remain after 16days

Pollutants Ceratophyllum demersum

Elodea canadensis

Lemna minor

Metolochlor 1.44 % 4.06% 22.7%

Atrazine 41.3% 63.2% 85%Sources:

Rice et al., Iowa State

University

LimitationsLimitations

ConclusionsConclusions Incineration: Effective but high risk to human health

Bioremediation & Phytoremediation has been seen as an innovative alternative with great potential that should be explored and developed (Frazar,2000)

Despite its limitations; minimal exposure of contaminants to human environmentally safe cheap

Thank YouThank YouQ&A SessionQ&A Session