April 22, 2003
Earth Tech, Inc.
Personnel: John Bassett

Topographical Map of NW Springs Basin

INTRODUCTION

As requested by the U.S. Environmental Protection Agency (EPA), Tetra Tech EM Inc. (Tetra Tech) is conducting site visits and performing oversight of investigative activities at the Neal's Landfill site in Bloomington, Indiana. Tetra Tech is performing this work for EPA under Contract No. 68-W6-0037, Work Assignment No. 943-RSBD-0539. Tetra Tech's subcontractor, Earth Tech, Inc. (Earth Tech), provided field oversight of dye tracing test activities performed by Viacom, Inc. (Viacom), the responsible party for the site. PSARA Technologies, Inc. (PSARA), is Viacom's consultant.

This report summarizes Earth Tech's activities at the Neal's Landfill site on April 22, 2003, and discusses Earth Tech's observations as well as issues and developments and future activities at the site. Appendix A contains a photographic log of Earth Tech's field activities, Appendix B contains a copy of Earth Tech's field notes, and Appendix C contains an Earth Tech figure showing various Neal's Landfill survey locations and dye tracing test results. These locations were observed during field survey investigations performed in November and December 2002 and January 2003 to identify potential dye tracer injection points around the site (refer to Tetra Tech's field oversight summary dated January 6, 2003, and Earth Tech's memoranc; m dated January 9, 2003 [which is included as Appendix ~ . -a Tech's field oversight summary dated April 22, 2003]).

ACTIVITIES AND OBSERVATIONS

Viacom, PSARA, and Earth Tech visited two dye tracer injection points previously identified on residential properties during the December 17, 2002, and January 7, 2003, field surveys at the Waggoner sinkhole (sink) and the Hamilton sine, respectively. In addition, Dr. Noel Krothe, Professor of Hydrogeology, Indiana University Department of Geological Science (IU), and Phil Schonhoff of the Indiana Department of Environmental Management (IDEM) observed the field activities. Viacom's objective was to perform two dye tracer injections, one each at the Waggoner sink and Hamilton sink, in order to better delineate the Northwest Spring System's Groundwater drainage basin.

The first location for dye injection was on the Waggoner property. This location was identified on December 17, 2002, and the landowner gave permission for testing on the property (refer to Tetra Tech's field oversight summary dated January 6, 2003). The location lies about 50 feet north of Holland Hill Road (see Photograph No. I in Appendix A and sink location no. 3 in Appendix C). Holland Hill Road is about 3,000 feet east of Cave Road, which is about 3,000 feet east of the Neal's Landfill entrance gate. At 9:40 a.m., Viacom and PSARA injected 200 grams (I liter of a 20 percent solution) of Rhodamine WT dye into the Waggoner sink (see Photograph No. 2 in Appendix A). The sink was then flushed with 2,000 gallons of water to carry the dye into the groundwater system. After flushing the Waggoner sink and packing up all their equipment, Viacom and PSARA went to the next dye tracer injection location, the Hamilton sink, accompanied by Earth Tech, IU, and IDEM.

The second location for dye injection was on the Hamilton property. This location was identified on December 17, 2002, as an area containing sinks for Potential dye injection, but the landowner did not return Viacom's telephone calls to give permission. to .;urve~ He property at that time. The location was visited again on January 7, 2003, and the landowner gave permission for testing on the property (refer to the Tetra Tech field oversight summaries dated January 6 and April 22, 2003). The Hamilton residence is located on the southeast corner of the intersection of State Route 48 and Cave Road; this intersection is about 3,000 feet east of the Neal's Landfill entrance gate. At 11:48 a.m. on April 22, 2003, Viacom and PSARA injected 125 grams (0.25 liter of a 50 percent solution) of Fluorescein dye into the Hamilton sink. The sink was then flushed with 2,000 gallons of water to carry the dye into the Groundwater system (see Photograph No. 3 in Appendix A).

In general, both dye tracer injections went well, and both sinks accepted water at the maximum flow rate that Viacom could achieve from the water holding tank (about 100 gallons per minute). The Hamilton sink did exhibit some pending of water after flushing (see Photograph No. 4 in Appendix A); however, this pending was not expected to affect the dye tracing test. The injections were generally performed in accordance with the "Scope of Work for Northwest Springs Basin Delineation Dye Tracing" document submitted by Viacom to EPA on January 28, 2003.

Viacom used five autosamplers (the ones that were used during the April 15, 2003, dye tracing test and that had remained in place since the test) for collection of surface water samples at various time intervals before and after the dye injections. The samples were collected at the following locations: (1) South Spring, (2) the Conard's Branch culvert, (3) Rogers Spring, (4) Branham Spring, and (5) Richland Spring. Viacom substituted the Branham Spring location for the Taylor Spring location that was identified in the scope of work document. This substitution was made because Branham Spring had a much greater flow rate at the time of testing. Also, Viacom collected surface water grab samples at various locations before and after the dye injections. The grab samples were collected at (1) North Spring, (2) Pig Pen Spring, (3) Taylor Spring, (4) Oard Spring, (5) Anderson Spring, and (6) New Rogers Spring. These samples were collected with less frequency than the samples collected at locations with autosamplers.

ISSUES AND DEVELOPMENTS

Tetra Tech reported in its field oversight summary dated April 22, 2003, that Viacom injected 125 grams (1 liter of a 50 percent solution) of Fluorescein dye into the Edwards sink. This is partially incorrect. The correct volume that Viacom injected into the Edwards sink was 0.25 liter of a 50 percent solution, which equals about 125 grams of Fluorescein dye.

Preliminary analytical results for the dye concentrations in the surface water samples collected by Viacom before and after the dye injections on April 15, 2003, have recently become available. Viacom is currently interpreting the results and believes that a storm in the site area may have affected the results based on the turbidity in the samples. Viacom's geologist, Mike McCann, reported the following information in an e-mail sent to the government agencies involved, Tetra Tech, and Earth Tech on April 21, 2003

Some Conard Branch Overflow samples are missing because the auto sampler failed to collect the sample. A thunderstorm occurred Sunday night 4/20/03 about 1800 hours. Samples at Richland springs, Rogers spring, and Branham were noticeably turbid for the 4/20/03 2200 and 4/21/03 0600 samples. Slight turbidity was noticed in the other stations for those two samples. Richland and Rogers springs showed particularly higher than background fluorescence for those two time periods. Whether that represents tracer injected in this test is hard to say. It does show that before storm event tracing is attempted in this area, auto samplers should collect an entire storm hydrograph background.

Viacom is to submit the final sample analytical results for the April 15, 2003, dye tracing test in a report to EPA. Based on evaluation of the preliminary data, Viacom stated that it is apparent that most, if not all, of the dye injected during the April 15, 2003, test entered the Northwest Spring System at the Neal's Landfill site. Therefore, Viacom planned to continue investigating the Groundwater drainage basin with additional dye tracing tests, including the April 22, 2003, test discussed in this field oversight summary. In addition, Viacom is to send the preliminary sample analytical results for the April 22, 2003, dye tracing test to the government agencies, Tetra Tech, and Earth Tech by e-mail once the data are available.