Bioremediation of BTEX Compounds CE 679 Adv. Water and Wastewater Treatment By: Zach Maruska December 10, 2007

Outline Introduction Project Objectives Project Objectives Alternatives Alternatives Preliminary Design Preliminary Design Conclusions Conclusions

Introduction What is BTEX? What is BTEX? Benzene Benzene Toluene Toluene Ethylbenzene Ethylbenzene Xylene Xylene

Why is BTEX a Concern? Volatile Volatile Relatively water soluble Relatively water soluble Technical Outreach Services for Communities

Objectives BTEX remediation alternatives BTEX remediation alternatives In situ vs. ex situIn situ vs. ex situ Design the selected alternative Design the selected alternative Oxygen or other nutrients needed for degradationOxygen or other nutrients needed for degradation

Treatment Alternatives Ex Situ Ex Situ Pump and treatPump and treat More controlMore control CostlyCostly In Situ In Situ Injection pointsInjection points Additional nutrientsAdditional nutrients

Aeration conditions Aerobic Aerobic Higher costsHigher costs Shorter treatment timeShorter treatment time Anaerobic Anaerobic Low initial costLow initial cost Typically lower O&M costsTypically lower O&M costs Longer treatment timeLonger treatment time

Design Alternative In situ remediation of BTEX In situ remediation of BTEX Less costlyLess costly Aerobic Aerobic Shorter treatment timeShorter treatment time Oxygen Release Compound (ORC ® )*Oxygen Release Compound (ORC ® )**Regenesis

Oxygen Release Compound When hydrated, ORC ® releases O 2When hydrated, ORC ® releases O 2 Releases O 2 for up to one yearReleases O 2 for up to one year Controlled Release Technology avoids foamingControlled Release Technology avoids foaming ORC ® produced by Regenesis

ORC ® Advantages Aerobic conditions without O&M costs Aerobic conditions without O&M costs Controlled release of oxygen Controlled release of oxygen Long-term source of oxygen Long-term source of oxygen Clean, non-disruptive application Clean, non-disruptive application No harmful by-products No harmful by-products

ORC ® Considerations ORC ® vs. ORC Advanced ® ORC ® vs. ORC Advanced ® Both Provide OxygenBoth Provide Oxygen ORC Releases 10% of its weight as O 2ORC Releases 10% of its weight as O 2 ORC Adv. Releases 17% of its weight as O 2ORC Adv. Releases 17% of its weight as O 2 ORC Adv. is an oxidizing compoundORC Adv. is an oxidizing compound More Hazards Associated with ORC Adv.More Hazards Associated with ORC Adv.

Design Parameters Site Parameters Site Parameters 30’ x 60’ x 10’ 30’ x 60’ x 10’ Porosity of Soil = 0.35 Porosity of Soil = 0.35 Concentrations of BTEX compounds Concentrations of BTEX compounds 5 mg/L, 2 mg/L, 5 mg/L, & 8 mg/L (respectively) 5 mg/L, 2 mg/L, 5 mg/L, & 8 mg/L (respectively) Total Concentration = 20 mg/LTotal Concentration = 20 mg/L Source has been stopped Source has been stopped

BTEX Degradation Stoichiometry Stoichiometry Benzene – C 6 H O 2  6CO 2 + 3H 2 OBenzene – C 6 H O 2  6CO 2 + 3H 2 O Toluene – C 7 H 8 + 9O 2  7CO 2 + 4H 2 OToluene – C 7 H 8 + 9O 2  7CO 2 + 4H 2 O Ethylbenzene – C 8 H O 2  8CO 2 + 5H 2 OEthylbenzene – C 8 H O 2  8CO 2 + 5H 2 O Xylene – C 8 H O 2  8CO 2 + 5H 2 OXylene – C 8 H O 2  8CO 2 + 5H 2 O O 2 requirements O 2 requirements Approximately 3.13 g O 2 /g BTEX Approximately 3.13 g O 2 /g BTEX

Design Concentration of BTEX = 20 mg/L Concentration of BTEX = 20 mg/L 62.5 mg O 2 /L 62.5 mg O 2 /L ORC releases 10% of its weight as O 2 ORC releases 10% of its weight as O mg ORC/L 625 mg ORC/L 1,250 mg ORC/L (with F.S. = 2) 1,250 mg ORC/L (with F.S. = 2)

Site Layout

Design 5-ft Radius For Injection Points 5-ft Radius For Injection Points 37 Injection Points 37 Injection Points 7800 L of Water per Injection Point 7800 L of Water per Injection Point 9.6 kg of ORC ® per Injection Point 9.6 kg of ORC ® per Injection Point 800 lbs of ORC ® Required 800 lbs of ORC ® Required $8,000 for ORC ® $8,000 for ORC ®

Conclusions In Situ is more cost effective In Situ is more cost effective Aerobic will allow faster remediation Aerobic will allow faster remediation Oxygen Release Compound (ORC ® ) eliminates the need for above ground piping Oxygen Release Compound (ORC ® ) eliminates the need for above ground piping ORC ® is a cost effective alternative for aerobic biodegradation of BTEX ORC ® is a cost effective alternative for aerobic biodegradation of BTEX

References Attra, Kevin. Environmental Analysis of BTEX Compounds in Soil, Water and Sludge by GC/PID. Phelps, Craig D., L. Y. Young, (1998). Anaerobic biodegradation of BTEX and gasoline in various aquatic sediments. Biodegradation, 10, Regenesis, Advanced Technologies for Groundwater Resources, (2006). Tiehm, A., S. Schulze, (2003). Intrinsic Aromatic Hydrocarbon Biodegradation for Groundwater Remediation. Oil & Gas Science and Technology, Vol. 58, No. 4, pp TOSC Environmental Briefs for Citizens. BTEX Contamination.

Questions? Thank you!