U.S. Department of the Interior U.S. Geological Survey Preliminary Results of Dye- Tracer Test at the B4 Area and Offsite Wells Dye Injection 11/13/07 Results up to 1/8/08 (8 weeks)

Preliminary Results 2000 Results Air Force Plant 6 Dobbins Air Force Reserve Base B-4 Area Southern Polytechnic State University Life University Rottenwood Creek Sites with TCE detections MW0s2

Preliminary Results Objective and Approach  Better understand ground-water movement in deep bedrock from B4 to offsite area  Selected two on-site wells (OB203 and RW203) that were located close enough to each other for an initial test.  Also included off-site bedrock wells in the test that were located downgradient from the injection well.

Preliminary Results Tracer Test Location Map

Preliminary Results Sampling Frequency  Weekly sampling at RW203  Monthly sampling at other sites

Preliminary Results Pre-Injection Background Sampling  Fluorescein (Acid Yellow 73)  Eosine (Acid Red 87)  Rhodamine WT (Acid Red 388)  Sulphorhodamine B (Acid Red 52)  Tinopal CBS-X (Fabric brightening agent 351)  Solophenol 500% (Direct Yellow 96)  D&C Red #28  FD&C Red #3  D&C Green #8  Palanil Luminous Red G  Lissamine FF

Preliminary Results Injection 1300  Set 1-inch PVC to 90 ft  1 gal #3 Red (pre-mixed)  Followed by 15 gal water (Flowmeter indicated no flow below 105 feet)

Preliminary Results Downgradient Monitoring Well RW203  Downward flow between 100 and 139’  Zero flow below 139’  Dye receptor placed at 105’

Preliminary Results Results: Injection 1300 ob203aRW203 92’380’880’ SCT2 SCT1 A B C A B C SCT3 ( ) (88-105) ( ) ( ) (85-125) (65-95) (139) (100) ( ) Depths in parentheses (not to scale)

Preliminary Results Results – 3 Days ob203aRW203 92’380’880’ SCT2 SCT1 A B C A B C SCT3 Not sampled ( ) (88-105) ( ) ( ) (85-125) (65-95) ( )

Preliminary Results Results – 2 Weeks ob203aRW203 92’380’880’ SCT2 SCT1 A B C A B C SCT3 ND ND (.030) ? ( ) (88-105) ( ) ( ) (85-125) (65-95) ( )

Preliminary Results Results – 5 Weeks ob203aRW203 92’380’880’ SCT2 SCT1 A B C A B C SCT3 ND ND (.050) ND 6650 ( ) (88-105) ( ) ( ) (85-125) (65-95) ( )

Preliminary Results Results – 8 Weeks ob203aRW203 92’380’880’ SCT2 SCT1 A B C A B C SCT3 ND ? (not sampled) ND 201 ( ) (88-105) ( ) ( ) (85-125) (65-95) ( )

Preliminary Results Map 8-Weeks

Preliminary Results All Results Location Distance (ft)3-DAYS2-WK3-WK5-WK8-WK RW-203 (100, 139) SCT2-C (85-125)384 ND.365 (.292) (8.937) SCT2-A ( )384 (0.05)(0.916) SCT-2B ( )384 (ND) SCT-3 (65-95)400 ND (ND) MW0S-2R (133)528 ND (ND) MWOS-03 (11-21)531 ND (ND) Trib-1633 ND (ND) SCT1-C (88-105) (4.272) (12.712) SCT1-A ( )879 ND

Preliminary Results What would cause such a highly constrained flow path? Why is the flow rate so high?

Preliminary Results I IV III II I-B Dominate strike of foliation = green, joints = red

Preliminary Results Parting Plane

Preliminary Results Findings (so far)  Fastest GW movement is through transition zone with flow rates on the order of 25 to 50 ft/day  GW movement appears to be strongly constrained along discontinuities formed parallel to foliation/layering (i.e. parting planes and lithologic contacts)  A downward hydraulic gradient in the area appears to influence deeper GW movement

Preliminary Results Tracer Test Continued…  Stay tuned  Sampling every 3 weeks  Will continue to sample until dye passes through system or we are satisfied with results  Other zones/wells may be tested