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A Historical and Technical Review and Analysis of TCE Contamination in the

South Hill Area of Ithaca, New York

A report to the Citizens of South Hill

By

Students in BEE/EAS 471 with input from faculty and citizens of Ithaca

June15, 2006

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Executive Summary

Trichloroethylene, or TCE, was used by the Borg-Warner Corporation in their Morse

Chain facilities on Ithaca’s South Hill in the 1960’s and 70’s. In 1987, four years after

the site had been acquired by Emerson, Emerson found TCE in oil that had been taken

from the surface of the large fire reservoir on the plant site. Further tests disclosed that

TCE had entered the subsurface environment near the fire reservoir. Other TCE spills of

unknown amounts and locations may have also occurred.

Both the health effects and economic fallout due to TCE contamination and transport

are of major concern to the current residents of South Hill. Assemblywoman Barbara

Lifton asked Cornell University to provide “another set of eyes” to examine data related

to the spill on behalf of the community members. The purpose of this document is to

provide the community members of South Hill with a report that addresses the scientific

basis of these concerns as well as the limitations of our current understanding.

Toxicological effects of TCE have been shown, at least at the occupational level, to

increase the risk of some cancers, liver and kidney damage, and headache/drowsiness. At

lower concentrations, effects on the immune system, respiratory system and neurological

system have been reported. However, low-level long-term toxic effects of TCE are not as

well studied. Economic impacts of concern include house devaluation and the operating

costs associated with TCE mitigation systems. One of the main concerns of the

community members is the process by which the determination of who will receive a

mitigation system is made. Based on the rough calculations of total expenses to Emerson

and the intrinsic benefit of having a supportive group of community members, it may be

beneficial to examine alternative testing and mitigation strategies.

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Testing and mitigation alone will not solve this contamination problem. It is

necessary to know how TCE behaves in the subsurface to understand the persistence of

TCE and identify possible pathways through which TCE enters homes on the South Hill.

Information on site characteristics of the South Hill, including geology and hydrology,

aided in attempting to understand TCE behavior in this report. For example, some site-

specific properties that influence TCE behavior are the fractured shale and climate. TCE

inhabits the fractured shale and forms pools and residuals that are extremely difficult to

locate and are likely impossible to entirely remediate. The transport of TCE from the

subsurface pools to the ground surface is not entirely understood. Mechanisms described

in this report include: diffusion, vapor intrusion, and arrival of contaminated water to the

surface. However, it is very difficult to deduce the relative importance of the different

pathways without additional monitoring. Understanding the pathways is crucial to

developing effective remediation strategies, as it is the limitations on this understanding

which shape the decision fabric.

.

The unpredictable variability of measured TCE concentrations indicates the need for

more extensive sampling to understand how patterns in seasonal fluctuations, spatial

variations and ground water trends influence the behavior of TCE. Because current

sampling methods available to residents are expensive, a review of simple and

inexpensive sampling and analytical strategies that could be pursued by Cornell students

has been provided herein. Successful collection of data with the proposed plan for spring

water and basement air sampling may aid in determining optimum conditions for indoor

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air sampling, as well as confirm that current sampling strategies provide justifiable long-

term averages of indoor contaminant concentrations.

Finally, TCE degrades more readily in an oxygen-free environment than in areas

where oxygen is present. TCE has a low solubility in water, which limits mobility and

biological degradation. Additionally, TCE degradation at the South Hill is retarded by

the cold subsurface temperatures. As a result, TCE can stay in the subsurface for

decades. Further research on the microbiological flora, groundwater, pollution source(s),

and sampling strategies is necessary in order to better understand what is happening to

TCE in the subsurface. However, this report concludes that TCE could be present in

small pockets within the subsurface, several mechanisms are likely transporting TCE to

the surface (although molecular diffusion likely dominates), and that remediation

measures that focus on reducing TCE entering homes, rather than the subsurface sources,

will be more effective in protecting the health and welfare of residents.

The overall objectives of this report are to address the following questions: How is

TCE, a chemical last used more than a quarter of a century ago, still of concern to the

residents downhill of the source? How dangerous is it? How does it move? What is its

future?

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About the Authors

After getting a BS degree in Environmental Engineering from Mersin University (Turkey) in 2002, M. Ekrem Cakmak received a MS degree from the Department of Environmental Engineering at Cukurova University (Turkey) in 2004. From there Ekrem was admitted as a PhD student in Biological and Environmental Engineering at Cornell University in Jan 2005. At Cornell, Ekrem is studying in the Soil and Water Laboratory under Tammo Steenhuis. Previously he was employed as a research assistant beginning in Dec 2003 and has been supported since Jan 2005 by Cukurova University. After completing PhD program Ekrem will return to Cukurova University. Contact: mec68@cornell.edu Web: www.geocities.com/mecakmak Larry Cathles joined the Cornell faculty as Professor in 1987, having worked at Kennecott’s Ledgemont Research Laboratory, Penn State University, and Chevron Oil Field Research. His main focus of research is the organic and inorganic chemical interactions associated with natural fluid. Recent topics considered include defining current natural hydrocarbon fluxes, capillary and dynamic controls on permeability, physical-chemical aspects of hydrate deposition and dissolution, and the rapid controlled venting of volatiles from intrusions. Cathles is a fellow of the American Association for the Advancement of Science and a member of several professional societies. He has served on committees of the National Research Council and is a past associate editor of Economic Geology. In 1985 he won the Extractive Metallurgy Science Award of the Metallurgical Society of the American Institute of Mining, Metallurgical, and Petroleum Engineers. He has taught Ground Water Hydrology with Steenhuis and others since 1987. Ken Deschere has been a resident of Ithaca since 1967, and has lived on South Hill Terrace since 1981. Ken received his BA in Applied Mathematics (Computer Science) from Cornell in 1971 and specializes in design and maintenance of database systems for international health insurance administration. He is Vice President of International Educational Exchange Services. He and Regina have two sons, Jonathan and Brian. Rachel Dunn got her master's degree in Chemical Engineering at King Mongkut's University of Technology Thonburi in Thailand and her bachelor's degree in Environmental Engineering at the University of Waterloo in Ontario. She recently joined Cornell's Biological and Environmental Engineering department to study watershed management both in Ithaca and in Thailand.

James W. Gillett (Ph.D. Biochemistry, UC-Berkeley; BS, Chemistry, Kansas) came to Cornell University in 1983 from the USEPA Corvallis Environmental Research Laboratory and the Environmental Health Sciences Center at Oregon State University to start an ecotoxicology program concentrating on exposure to pesticides, hazardous wastes, and toxic chemicals. He was the director of Cornell's Institute for Comparative

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& Environmental Toxicology (`86-`92) and headed the Cornell Superfund Basic Research Program (`93-`02) which emphasized work on volatile organics, PCBs, and lead. Recent efforts have expanded physical, mathematical and conceptual modeling of exposure assessment in ecosystems to risk analysis, management and communication more broadly. This has led to long-term efforts with the Mohawks at Akwesasne on the St. Lawrence and assisting citizens adjacent to superfund sites, such as the Elmira Southside High School and Seneca Army Depot.

Adrian Harpold is a Ph.D. student working for Dr. Tammo Steenhuis in the Biological and Environmental Engineering Department at Cornell University. Adrian's interests center around Land and Water Engineering related to nonpoint source pollution, physical hydrology, public policy, and soil and water conservation in developing countries. Adrian has a B.S. and M.S. from Virginia Tech in Biological Systems Engineering. His Ph.D. work will look at developing travel time estimations using chemical signatures in watersheds in the Catskills, NY. Adrian is from Seattle Washington, but has lived in Winston-Salem, NC, Blacksburg, VA, and Logan UT. Veronica Morales is a first year M.Sc./PhD student in the department of Biological and Environmental Engineering at Cornell University, working under the supervision of Dr. Tammo Steenhuis. She finished a B.S. degree from the University of California, Santa Barbara in 2004 in the field of Environmental Science, Hydrology. Her research interests include the transport and fate of pollutants in the subsurface. In the past, Veronica has worked on other TCE research projects through the University of California, Davis on the Evaluation of Field Methods for Measuring Contaminant Mass Discharge in Flowing Aquifers at Vandenberg Air Force Base in California. Rachel Shannon received her B.A. in geology from the University of Colorado at Boulder in May of 2002. During her undergraduate, she had the opportunity to work in a variety of geological applications. Most of her time was spent in a geophysics lab as part of a larger project to develop a new method to detect the movement of contaminant plumes (such as TCE) through the ground. She was also involved in some shorter-term projects she did mostly for fun: one summer she spent hiking and mapping the Blue Ridge Mountains in North Carolina, and during her senior year she worked in an isotope geochemistry lab age-dating rocks and archaeological artifacts. After graduation, she went to work as a geologist for a company that makes software used by oil companies to help locate and evaluate oil reserves. After two years there, she came to Cornell for her Master's degree. With Larry Cathles, her adviser, she is studying the source of a large copper deposit in Montana. Rachel will graduate in the summer of 2006. Brianne Smith is a junior in the School of Engineering at Cornell University. She is majoring in biological engineering as well as environmental engineering. Brianne is a co-op employee at Merck & Co. and plans to begin work on a Masters of Engineering degree in the spring of 2007. Jennifer Smith is a Master of Science student at Cornell University in the Department of Biological and Environmental Engineering. She is graduating from the Environmental

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Engineering program, with a minor in Risk Assessment, Communication and Policy. Her undergraduate degree was from the University of Idaho, in Biological Systems Engineering with an Environmental Engineering emphasis and a minor in Mathematics. She will be working at a consulting firm starting this summer in Seattle, WA. Ian Toevs is currently finishing his Master of Science degree at Cornell University in the Biological and Environmental Engineering department with an emphasis in Soil and Water Engineering and studying under Tammo Steenhuis. Ian received his BS degree in Agricultural Engineering from the University of Idaho in 2004 with a minor in Outdoor Recreation Leadership. Ian will start work in the summer of 2006 at Barton and Loguidice, P.C. in Syracuse as an environmental engineer and geohydrologist. Tammo Steenhuis is Professor of Water Management in the Department of Biological and Environmental Engineering. He runs a group of 20 graduate students, 3 research associates and one post doctoral assistant and is an expert in the transport of water and chemicals in the landscape. He is concerned with determining the best methods of managing soil and water resources and landscape processes in both the USA and developing countries by better understanding of the complex interrelations among morphology, water flow, plant growth, and fertility. His group’s findings are incorporated in models that require only easily available data. Research proceeds from basic processes to fundamental and universally applicable solutions to engineering design problems in water management and pollution control. Current projects concern the movement and fate of pathogens, metals, pesticides and phosphorus in the Catskills, Ethiopia, Mali and Ghana. For more information see: http://www.bee.cornell.edu/swlab/SoilWaterWeb/index.htm

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Table of Contents Executive Summary ............................................................................................................ ii Tammo Steenhuis.............................................................................................................. vii Introduction......................................................................................................................... 1 Section 1: Site History ....................................................................................................... 4

The early years................................................................................................................ 4 Growth through the 20th century.................................................................................. 12

Section 2: Toxicological Profile for Trichloroethylene (TCE)........................................ 20 Introduction................................................................................................................... 20 Environmental Fate ...................................................................................................... 21 Exposure ....................................................................................................................... 24 Toxicological Endpoints ............................................................................................... 25 TCE Metabolism ........................................................................................................... 27

Section 3: Economic Analysis .......................................................................................... 29 Real Estate Value .......................................................................................................... 29 Mitigation Operating Cost ............................................................................................ 30 Overall Economic Analysis........................................................................................... 31 Conclusions................................................................................................................... 34

Section 4: Geology............................................................................................................ 36 Section 5: Hydrology ....................................................................................................... 40

General information about water transport through the subsurface............................ 40 Physical controls on groundwater movement at South Hill ......................................... 42

Geologic and Soil Controls on Groundwater Movement ......................................... 43 Human Induced Transport Mechanisms ................................................................... 45

Conclusions................................................................................................................... 47 Section 6: Spring Water and Basement Air Sampling...................................................... 48

Spring Water Sampling ................................................................................................. 48 Basement Air Sampling................................................................................................. 51 Conclusions................................................................................................................... 60

Section 7: Subsurface Transport of TCE ......................................................................... 63 Section 8: Mechanisms of TCE Transport at South Hill .................................................. 66

Deep Percolation of TCE into the Bedrock .................................................................. 66 “Back Diffusion” of TCE in the Bedrock ..................................................................... 68 Contaminated Water Reaching the Surface .................................................................. 68 Degradation of TCE in Soil .......................................................................................... 70 Diffusion of TCE in Soil and Air................................................................................... 71 Vapor Intrusion of Contaminated Soil Air.................................................................... 72

Section 9. Operational Suggestions .................................................................................. 75 Appendix A. Glossary of Terms ...................................................................................... 78 Appendix B. GIS Maps.................................................................................................... 82 Appendix C: Relative Magnitudes of Diffusion and Vapor Intrusion…………………..86 Appendix D: References ................................................................................................... 88

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List of Figures

Site History: Figure 1-1: Lower South Hill 1905 Page 5 Figure 1-2: National Cash Register Ad – 1962 Page 7 Figure 1-3: Morse Ad- 1962 Page 9 Figure 1-4: Therm Ad 1990 Page 11 Figure 1-5: Sanborn" Map of Morse Chain Site, early 1960's Page 13 Figure 1-6: Outfall Discharge Map Page 15 Economics: Figure 3-1: Worst case scenario of contaminated area. Page 32 Geology: Figure 4-1: Diagram of a hypothetical slice through South Hill Page 37 Figure 4-2: Schematic Drawing of Rock Joints Page 38 Hydrology: Figure 5-1: Water Transport Mechanisms Page 40 Figure 5-2: Water Transport: Seeps and Springs Page 42 Figure 5-3: Water Table Heights for 5 Measuring Wells Located Near the Fire Reservoir Page 44 Figure 5-4: Electrical Resistivity Results for South Hill Moving in a Southwest Direction Page 45 Figure 5-5: Garage Where Water Can Be Transported Through a Wall Built in the Topsoil Page 46 Spring Water and Basement Air Sampling: Figure 6-1: Passive Diffusion Sampler for Organic Vapor Page 54 Figure 6-2: Active Sampling Set-up Page 56 Figure 6-3: Chromatogram (Carbon Disulfide and TCE Peaks) Page 58 Groundwater/Transport: Figure 7-1: Transport Processes in Subsurface Page 63

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Figure 7-2: Mean annual earth temperatures at individual stations, superimposed on well water temperature contours Page 64 Mechanisms of TCE Transport at South Hill Figure 8-1: One possible scenario for TCE transport in a fractured

bedrock scenario Page 67 Figure 8-2: Process of transport and back-diffusion in a simplified fracture channel Page 67 Figure 8-3: Graph of Concentration of TCE in water versus the volume necessary to achieve 5 ppb TCE in the air of a 40 X 40 X 10 ft basement Page 69 Figure 8-4: Schematic of a house where tile drains are used to drain a high water table Page 70 Figure 8-5: The rising water table can move TCE into the soil pores near the surface Page 72 Figure 8-6: Diagram of ‘Stack Effect’ Page 74 Figure 8-7: Vapor intrusion occurs along a below-ground sewer pipe Page 74 Figure 8-8: Possible scenario for TCE movement in shallow soil Page 74

List of Tables Table 1-1: Groundwater TCE readings in the summer from MW-3-31 Page 17 Table 1-2: Groundwater TCE readings in 2003 from MW-3-31 Page 17 Table 1-3: Repeat TCE analyses of basement air Page 19 Table 6-1: EPA Recommended Sorbent Materials Page 56

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Introduction L. M. Cathles and T.S. Steenhuis

In December of 2004, Gary Stewart of Cornell University sent an email to

potentially interested faculty on behalf of President Lehman’s office. The email

forwarded a request from Assemblywoman Barbara Lifton asking help in examining data

related to the Emerson TCE spill. Lifton’s request indicated that affected homeowners

would value “another set of eyes” on the groundwater and other data related to the

Emerson contamination.

In the spring of 2005 Professors Steenhuis (Department of Biological and

Environmental Engineering) and Cathles (Department of Earth and Atmospheric

Sciences) used the Emerson TCE case as a project in their Introduction to Ground Water

Hydrology (BEE&EAS 471) class. The class produced a report on the geology,

hydrology and chemistry of the site. That report can be found at

(http://www.bee.cornell.edu/swlab/SoilWaterWeb/testimony/southill.htm). Professors

Steenhuis and Cathles presented the conclusions of the class study at a DEC public

hearing (http://assembly.state.ny.us/comm/Encon/20060201/) that spring.

In the fall of 2006 several homeowners contacted Cathles and Steenhuis to request

Cornell’s assistance and analysis on the matter. Again, the Ground Water Hydrology

class was used to investigate the complex situation at Emerson. In the spring of 2006, the

class self-organized as a “task group” under the leadership of Ian Toevs, a MS student

who had been involved in the study the previous year, to investigate all aspects of the

TCE problem near Emerson. The group was advised mainly by Cathles and Steenhuis,

but received substantial input and guidance from Professors Brown, Gillett, Gossett,

O’Rourke, and other faculty at Cornell. The students also solicited presentations from

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Dr. Shree Giri (sampling and measurement methods of volatile organics) and Dr. Darien

Simon (sociology of communications in contamination cases), along with open and

exceptionally useful communications with Carl Cuipylo of the New York State

Department of Environmental Conservation. A subgroup of students had one detailed

meeting with Mr. Cuipylo and Jim Burke at the DEC offices in Syracuse. Dr. Brown

facilitated the use of ground penetration radar survey on part of the affected

neighborhood. A group of three homeowners (Regina and Ken Deschere and Stanley

Scharf) attended every one of the weekly class sessions throughout the Spring 2006

semester. They guided the class with the information they had already assembled, and

provided an invaluable perspective that helped the class sift through the masses of

Emerson material available in the Tompkins County Library. The introductory (history)

chapter of this report was written by Ken Deschere.

The product of the class task group is this report to the homeowners. It digests a

large amount of information and describes poorly understood phenomena of TCE

transport with "fresh eyes” in a way that is intended to be clear to non-technical readers.

Thus, the intent is to elucidate what appears to be occurring at this TCE site as well as all

the problematic aspects associated with it.

Best efforts have been made to ensure that the report contains no major errors and

the report has been augmented and edited slightly by Cathles and Steenhuis. At its heart

it is a class report and should be treated as such. Suggestions are given, but should be

taken as the products of brainstorming by students rather than as official

recommendations of Cornell University or any of its components. Formal

recommendations are for the homeowners or city representatives to make, and are not the

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purview of an academic class. Similarly, where conclusions have been suggested or

implied, they should be recognized as attempts to clarify or crystallize the implications of

the discussion. Conclusions are the purview of city/state agencies, or the affected

homeowners.

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Section 1: Site History Ken Deschere

The early years

South Hill was settled and developed much later than the downtown "core" of

Ithaca because Six Mile Creek formed a natural boundary to the south of the town. Much

of the "flats" west of South Hill (west of Cayuga Street, south of Green Street) were

swampy areas, and the initial settlement was centered in areas between the Inlet and

Aurora Street. (See the 1873 and 1882 "Birds-Eye" views of Ithaca in these maps from

The History Center. The maps show just modest development along Prospect, Pleasant,

and Columbia Streets on "lower" South Hill.)

In 1870 an iron bridge was built over Six Mile Creek at Aurora Street, which

eased access between South Hill and downtown Ithaca. The Morse Chain Company was

incorporated in 1898, and the early 20th Century saw considerable settlement and

development of lower South Hill, including the establishment of a large factory site, west

of Aurora Street and south of the railroad loop, which extended down the hill to

"Mechanics Street" (now Hillview Place) near Aurora Street.

Tioga Street was extended up South Hill from the intersection of Prospect Street

and "Spencer Place" (now known as East Spencer Street), which started southwest

toward Cayuga Street. This section of Tioga Street is now known as "Turner Place" - a

reference to Samuel B. Turner and his brother, Ebenezer T. Turner, who owned a large

parcel of land West of Tioga Street, running from Spencer Place up the hill to the rail

line. The K.P. Crandall map (dated May 1905 and reproduced here as Figure 1-1) is the

basis for most of the property lines dividing up the 38 lots they offered for sale. Note the

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"Ithaca Water Works" property, showing a city reservoir that was where the Morse "R &

D Lab / Service Building" was later built.

With a school and grocery delivery, homes were built in neighborhoods that

developed downhill from and east of the factory, including many of the lots owned by the

Turner brothers. There were a few cigar makers, a dairy, and a coal yard (which became

Southside Fuel Company, downhill from Coddington St. on Aurora St.).

Figure 1-1: Lower South Hill - 1905 - for a printable version, click here.

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Ithaca Gun was the first large factory operation to be established in Ithaca. It was

located on Lake Street, near the Ithaca Falls, where waterpower was readily available.

Since then, South Hill has hosted various industrial ventures. The first to be established

was the Morse Chain Company, which incorporated in 1898 in Trumansburg, growing

from a carriage-spring and bicycle-chain business into a developer of chain and power-

transmission equipment. The firm moved into their South Hill site in 1906. There were

many other product lines they worked with, including aircraft, typewriters, and adding

machines. The Thomas-Morse Scout plane was part of the aircraft industry centered at

what is now The Hangar Theater at Cass Park.

The Morse adding machine business was merged into a firm known as Allen-

Wales. In 1943 it was bought by National Cash Register Company. A new plant was

constructed further up South Hill in 1957-8, where the business continued until the

demise of mechanical adding machines in the 1970's. NCR moved into electronic point-

of-sale systems, and was taken over by Axiohm before the facility was closed around

2000. The owners of this factory site are applying for participation in the New York State

Brownfield Cleanup Program.

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Figure 1-2: National Cash Register Ad - 1962 (Source: Manning's Ithaca Directory Vol. LIX, 1962)

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Morse Chain and the many affiliated industries located in the same site expanded

through much of the 20th century, joining the Borg-Warner Corporation in 1929. Their

product lines evolved, including electronic controller components for power transmission

systems, manufactured in the building formerly occupied by the adding machine

operation.

In the early 1980s, the automotive portions of the business were moved to a new

facility on Warren Road near the airport. The Industrial products portion remained on

South Hill. The company was sold by Borg-Warner to Emerson in 1983, and is now the

main site for the Emerson Power Transmission operation.

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Figure 1-3: Morse Ad – 1962 (Source: Manning's Ithaca Directory Vol. LIX, 1962 )

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Therm has developed a large facility on Hudson St. Extension, with a 130,000

square-foot facility and recognized specialties in machining turbine blades. Therm has

also had many forays into other lines: typewriter components, television screens, engine

components and glassware.

While Therm has managed to avoid some of the serious scrutiny placed on the

Aurora Street sites, they have had to renew their State Pollutant Discharge Elimination

System (SPDES) permits after spills, which discharged down the hill into Six Mile

Creek.

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Figure 1-4: Therm Ad – 1990 (Source: Ithaca City Directory, 1990)

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Growth through the 20th century

The Morse facility on South Hill expanded through its first seven decades, with

the most significant and lasting development in power transmission equipment for

industrial and automotive applications: drive chains, timing chains, sprockets, gears and

combinations in various housings for front-wheel and four-wheel drive systems. The

plant layout and functions are suggested by the "Sanborn" map shown in Figure 1-5

below. This is a 1929 map that was updated to the early 1960's.

Activities included metal stamping, punching, grinding, milling, heat-treating, oil-

quenching, parts washing and product assembly. Other operations started in the 1960's

and 1970's included copper and cadmium plating, and wire drawing. Many of these

processes require the use of "cutting oils" which must be removed from the pieces after

the process. The removal steps involved a variety of solvents including mineral spirits,

Freon, 1,1,1-trichloroethane, TCE, and tetrachloroethane. While TCE use was

discontinued in 1977 or 1978, peak usage was reported to be about 1200 gallons per week

(per Radian consultants’ report, July 13, 1987).

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Figure 1-5: "Sanborn" map of Morse Chain Site, early 1960's for a printable version, click here.

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Environmental awareness and concerns about carcinogenic effects of the various

lubricants and solvents were not as developed in the mid-20th century as they are today.

However, the Morse facility, like many other industrial and military sites across the

country, became the focus of attention as neighbors reported odors, and strange colors

and oil slicks in water streaming downhill from the plant.

Some of the identified problems are documented in correspondence between

Morse employees and local and State health officials. Walter Hang of Toxics Targeting

Inc, has collected many of these documents. Cutting oils used in processing the metal

parts were widely dispersed. Oils coating the finished parts dripped off pieces of scrap

and shavings which were hauled in bins from the plant to recycling centers.

Polychlorinated biphenyls (PCBs) were found in this oil, and as our knowledge of the

problems with these synthetic chemicals grew, so did concern about the oil runoff from

the plant.

The use of chlorinated solvents as degreasing agents (to remove the oil from the

metal) increased in an attempt to limit the spread of the PCB-laden oil. However, as it

was learned that some of the active agents in these solvents themselves presented

problems, efforts were made to reduce their use.

The volumes of metal, cutting oils, solvents, and water that moved through the

plant site are large. The amount of metal scrap, and the oil with which it was treated, are

the subject of ongoing discussions between Morse staff and County Health officials. The

solvents used and the water taken in and discharged by the plant are detailed in the 1981

application Morse filed for a discharge permit (Figure 1-6).

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Figure 1-6: Map submitted as part of SPDES Permit Application, showing location of Outfall Discharges. A "Google Earth" view of these locations may be viewed here. The locations are: - uphill from the top of South Cayuga Street, and - below West Spencer Street, near the intersection of Wood and South Geneva

S

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In 1987, TCE was found in oil that had been taken from the surface of the large

fire reservoir on the plant site. Further tests disclosed that TCE was present in the

reservoir water as well.

According to the "Record of Decision" issued by NYSDEC in December, 1994,

these steps were taken over the next years:

February 1987: EPT notified NYSDEC of the discovery of TCE in oil skimmed off the surface of an underground fire reservoir. At this time, EPT hired Radian Corporation to prepare a preliminary environmental assessment to address TCE contamination in the fire reservoir and to investigate whether TCE had impacted groundwater. As part of this work, the reservoir was emptied and cleaned using high-pressure water and five monitoring wells were installed. Samples were collected of the groundwater from those wells, soil, surface water and sediment from Six Mile Creek, and seeps. This sampling showed local groundwater was contaminated and that the fire reservoir was likely a source. The study also detected petroleum hydrocarbons in soil taken from the railroad ditch. July 1987: The site was added to the New York State Registry of Inactive Hazardous Waste Disposal Sites. July 1988: EPT signed a consent order with the NYSDEC for a remedial investigation/feasibility study (RI/FS) and remedial program at the site. February 1990: Radian Corporation submitted the RI. This information was used to evaluate interim remedial measure (IRM) alternatives and to complete the Feasibility Study (FS). May 1991: EPT entered into a consent order for an IRM. August 1991: EPT finished construction of a groundwater extraction and treatment system (henceforth referred to as "pump and treat system") to operate as an IRM prior to completion of the FS. May 1991: NYSDOH collected air samples from homes near the Morse site. Based on these samples, the NYSDOH requested and EPT agreed to install vadose zone monitoring wells to assess the potential for impacts adjacent to the site. August 1992: The Fire Reservoir was rehabilitated and put back into service. Cracks in the concrete were patched and a liner was installed.

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February 1994: EPT completed a pilot test using the Xerox Two-Phase Vacuum Extraction system, which was initiated in October 1993. Pilot test objectives included: evaluating system effectiveness for removing VOCs from the soil, dewatered bedrock, and groundwater; comparing system performance to the pump and treat system; and evaluating the benefit of supplementing or replacing the pump and treat system with two-phase vacuum extraction for remediation. The pilot test results showed that the two-phase vacuum extraction system outperforms the pump and treat system. The two-phase vacuum extraction system removes greater quantities of groundwater, has higher VOC removal rates, and has a greater zone of influence. June 1994: Four vadose monitoring wells were installed and will be sampled on two occasions. This investigation will be completed concurrently with the monitoring program for the remedy selected by the PRAP. Should the need for further remediation or other mitigation be identified it will be evaluated as a component of the operation and maintenance program for the site.

The groundwater extraction system continued to be used, and results were

monitored. Readings from one well (MW-3-31, located East of the top of South Cayuga

Street, between the Fire Reservoir and the NYSEG Substation) are summarized in this

February 2004 report prepared by Radian. The readings vary wildly from season to

season and year to year: for TCE, summer readings

are listed in Table 1-1. These readings are all much

higher than the NYS DOH guideline of 5 μg/L

(micrograms per liter). Within 2003, the last year

reported, the results varied significantly as well,

shown in Table 1-2. After more than a dozen years

of groundwater extraction, levels were still very high

and showing little sign of abating.

In May 2004, Walter Hang, President of

Toxics Targeting, Inc. held a Press Conference

Table 1-2: Groundwater TCE readings in 2003 from MW-3-31.

Month TCE level (mcg/L) March 20 000 June 21 000 August 5 800 November 28 000

Table 1-1: Groundwater TCE readings in the summer from MW-3-31.

Year TCE level (mcg/L) 1996 6 900 1997 1 100 1998 82 000 1999 260 2000 43 000 2001 78 000 2002 28 000 2003 21 000

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below the Morse Plant to discuss the first of two letters he would send to Emerson and to

the NYSDEC, referencing the historic documents and maps his firm had collected and

prepared. The attention Mr. Hang's actions drew helped spur a variety of actions, many of

which are ongoing today.

The Toxics Targeting site has an archive of newspaper articles on these actions,

(through 2005), as does the Ithaca Journal, in which most of the articles first appeared.

Unfortunately, the Journal's archive stops at August 2005, and it seems as though no back

issues were kept online for public reference. Some of the articles are referenced at the

Yahoo! site - see below.

Many of the actions taken, documents involved, and opinions expressed are

available for review at the Yahoo! Groups site for Ithaca-SHIP. The focus of much

attention has been the continuing testing of the air and groundwater. Timothy Weber has

assembled a thorough database of the results of these tests, with interactive mapping to

help "see the forest for the trees". His database contains, among other data, all available

analyses of indoor TCE from three phases of testing (372 analyses in total; access from

above database link by selecting Chemicals by name, just site related in table, and then

selecting 1,1,1-Trichloroethane). As analyzed by Larry Cathles for this report, that data

shows that 35% (31) of the 89 basements tested (see Figure 3-1 for locations) contain

measurable levels of TCE. The TCE levels are generally in the 1 to 2 μg/m3 range (~0.2

to 0.5 ppbv). Several of the houses have been tested repeatedly. The repeatability of the

measurements appears good (about ±1 μg/m3), as shown in Table 1-3.

19

Table 1-3. Repeat TCE analyses of basement air samples taken from the same house. All measurements are in μg/m3 TCE. The data are from Ithaca-SHIP Yahoo web site of Timothy Weber. House #1 7.92, 7.16 House #2 3.7, 1.2, 1.37, 0.765,2.02, 1.09 (average 1.7 ± 1) House #3 1.3, 1.97 House #4 1.04, 0.492 House #5 2.3, 0.874 House #6 0.93, 0.82 House #7 1.4, 1.2, 0.437, 0.328 Not Detected 9 houses in two samplings 2 houses in 3 samplings

20

Section 2: Toxicological Profile for Trichloroethylene (TCE)

Jennifer Smith

Introduction

Trichloroethylene (TCE) is a legal organic chemical commonly used

commercially and in industry. It can be used as a solvent to clean grease from metal, a

paint stripper, an ingredient in paints and varnishes, an adhesive solvent and a chemical

to manufacture other organic chemicals. Consumer products that contain TCE include

typewriter correction fluids, paint removers/strippers, adhesives, spot removers, and rug

cleaning fluids (ATSDR 1997). Some common uses of TCE prior to an FDA ban in 1977

were as an anesthetic, grain fumigant, wound disinfectant, and pet food additive (ATSDR

1997). There were only two manufacturers of TCE in the United States as of 1986, with

a combined production of 320 million pounds annually (ATSDR 1997). In 1993, 16.3

million pounds of TCE was imported into the US and 72.6 million pounds of TCE was

exported (Fisher et al. 1998). In New York State there were 55 facilities that used TCE

for on-site use/processing in 1993 as a reactant, for repackaging, as a chemical processing

aid, as a manufacturing aid, or for other uses (ATSDR 1997).

The current limit for TCE in air for New York State according to the New York

State Department of Health (NYSDOH) is 1 ppbv (1 ppbv is one part per billion by

volume, e.g., 1 volume of gaseous TCE per billion volumes of air). OSHA allows an 8-

hour time weighted average exposure limit of 100,000 ppbv; the 15-minute time

weighted average limit for exposure is 300,000 ppbv (OSHA 1993). The threshold limit

value for occupational exposure is 50,000 ppbv (American Conference of Governmental

Industrial Hygienists 1997). The threshold limit value is the maximum value that most

21

adult workers are expected to be able to tolerate without adverse effects. Time weighted

average means that the value has been averaged over an 8-hour day/forty hour workweek.

For reference, TCE can be smelled at levels of 120,000 to 500,000 ppbv.

The National Institute for Occupational Safety and Health set a 60-minute ceiling

occupational exposure limit of 2,000 ppbv. Though these limits are higher than the

NYSDOH standard for indoor air (1 ppbv), a complicating factor in assessing the risk of

TCE exposure is that other contaminants are also generally present in environmental

cases that can act synergistically to increase risk. Additionally, sensitive individuals such

as children, pregnant mothers, the elderly, those who drink and those who smoke may

require a significantly lower level to ensure minimal risk.

Environmental Fate

TCE is the most commonly reported organic groundwater contaminant (Bourg et

al. 1992). In addition, between 9 and 34% of drinking water in the United States has

TCE contamination (ATSDR 1997). TCE is classified as a dense non-aqueous phase

liquid (DNAPL), since the specific gravity (ratio of chemical density to that of water) is

1.46 (US EPA 2005). TCE also has low solubility in water. This can potentially make

assessments of transport difficult, since migration into the vapor phase is dependent on

water concentrations, water table depth and fluctuations, and temperature. Migration in

the liquid phase can occur at increased rates compared to groundwater, due to the fact

that liquid TCE has a higher density than water. The organic carbon-partitioning

coefficient (Koc) for TCE has also been experimentally derived, with values from 106-

460 (Garbarini and Lion 1986). Koc is a measure of a chemical’s affinity for organic

matter in soils, where higher values correspond with higher retention in organic matter

22

(values greater than 1000). This indicates TCE will not sorb readily to organic matter in

saturated soils. TCE dissolved in groundwater is expected to move with groundwater

rather than sticking to organic matter. However, TCE may be physically trapped as

puddles of liquid TCE inside geological formations (discussed in geology and transport

sections).

Volatilization of TCE into a vapor phase in air occurs rapidly. The volatilization

half-life of 1 mg/L TCE was experimentally investigated as 21 minutes at 25oC (Diling et

al. 1975). Volatilization from the aqueous phase occurs at a much higher rate than the

volatilized TCE is degraded by photolysis or hydrolysis (Jensen and Rosenburg 1975).

Moreover, chemical hydrolysis only occurs at very high temperatures and pH - not under

normal conditions encountered in a natural environment (ATSDR 1997). Photolysis is

the degradation of a compound due to exposure to light, where photons break chemical

bonds. Hydrolysis occurs when chemical bonds are split by water. This indicates that if

liquid TCE or TCE dissolved in water is exposed to air, it will rapidly evaporate into the

vapor phase and increase the amount of TCE in air that may intrude into nearby

buildings. The amount of TCE that can be introduced into air by water containing TCE

or by liquid pools of TCE is very large compared to the health standards. The Henry’s

Law constant for TCE dissolved in water is 0.3 .rliter wate / TCE mg

airliter / TCE mg⎥⎦

⎤⎢⎣

⎡ The vapor

pressure of liquid TCE is 73 mm Hg. This means that air in contact with water saturated

with TCE (1100 mg TCE per liter of water) will contain 330,000 mg TCE per m3 air (or

>60,000,000 ppbv TCE). Air in equilibrium with a puddle of liquid TCE will contain

96,000,000 ppbv of TCE.

23

In deep subsurface regions, degradation (biotic or abiotic) is minimal. Rates of

biodegradation will be influenced by nutrient availability, temperature and weather TCE-

consuming organisms are present. Biodegradation of TCE can occur completely if

present in aerobic (oxygen present) conditions. Biodegradation may also occur under

anaerobic (oxygen absent) conditions, via reductive dehalogenation. This process occurs

when hydrogen replaces chlorine (the halogen) in a chlorinated compound sequentially.

However, the last chlorine in this process is very difficult to remove and therefore takes a

long time to completely degrade or mineralize to ethene (a benign degradation

compound). The second to last product is vinyl chloride, a known carcinogen. Vinyl

chloride can be mineralized biotically if aerobic conditions are then present. In nature,

conditions are commonly aerobic above the ground water table or in areas of rapid inflow

of surface water. In areas of relatively stagnant water below the water table, conditions

are generally anaerobic.

Bioconcentration refers to increased concentrations of a chemical in organism

tissues relative to environmental conditions. Biomagnification occurs when there is a

cumulative increase in the concentration of a chemical in organisms at successively

higher levels of the food chain. Bioconcentration and biomagnification of TCE are

virtually negligible. A study by Saisho et al. (1994) found bioconcentration factors of

4.52 and 2.71 for blue mussel and killifish, respectively. Biomagnification was

investigated in the aquatic food chain, where concentrations were less than 100-fold in

fish liver, sea bird eggs and sea seal blubber, suggesting some biomagnification (Pearson

and McConnell 1975). Laboratory studies of fruits and vegetables have found uptake of

TCE in the foliage of carrot and radish plants; bioconcentration factors were between 4.4

24

and 63.9 (Schroll et al. 1994). Bioconcentration factors that are less than 200 are

considered to be negligible in magnitude.

Exposure

The primary exposure pathways are: ingestion of contaminated drinking water or

inhalation (Wu and Schaum 2000). Inhalation is the primary route of exposure on the

South Hill. TCE is present in ambient air across the nation. In 1993 alone, 30.2 million

pounds of TCE was emitted into the atmosphere (ATSDR 1997). Ambient air

concentrations of TCE found in the United States ranged from 0.04-0.72 ppb, 0.39 ppb,

0.21-0.59 ppb in Oregon, Pennsylvania, and New Jersey, respectively, during 1983-84

(Ligocki et al. 1985, Sullivan et al. 1985, Harkov et al. 1984). Air concentrations in these

studies were found to vary between the fall/winter and spring/summer seasons. Wallace

et al. (1985) found indoor air to contribute more overall TCE exposure than outdoor air,

where the ratio of indoor to outdoor concentrations was about 5:1 in North Carolina.

Indoor air concentrations have been measured as 5 ppb in a North Carolina office

building, 0.14 ppb in a Washington, DC school and 0.15 ppb in an elderly home in

Washington, DC (Hartwell et al. 1985). The average inhalation uptake in the United

States can be estimated as 11-33 mg/day, and uptake due to oral exposure is

approximately 2-20 mg/day (Wu and Schaum 2000). Upon inhalation exposure to TCE,

about half will be absorbed into the bloodstream and the other half exhaled. Once in the

bloodstream, TCE will either be exhaled or modified in the liver and kidneys for urinary

excretion.

Other exposures to TCE can occur through food: dairy products such as milk,

cheese and butter (0.3-10 ppb), oils and fats (0-19 ppb), beverages such as canned fruit

25

drink, ale, instant coffee, tea and wine (0.02-60 ppb), fruits and vegetables (0-5 ppb) and

bread (7 ppb) (McConnell et al. 1975). Breast milk has also been shown to contain TCE

in 8 of 8 mothers sampled who resided in urban areas (Pellizzari et al. 1982). Though

these routes are generally not the primary mechanism of exposure, it is important to

consider the cumulative effects of these background levels with any additional sources.

Toxicological Endpoints

This is not a complete list of all toxicological endpoints of TCE, but a compilation

of the most studied effects found in the literature. The International Agency for Research

on Cancer has classified TCE as a probable human carcinogen, because there is sufficient

evidence in experimental animals but limited evidence in humans (Iavicoli 2005). TCE

toxicity in humans has been fairly well studied at higher concentrations, especially with

regards to occupationally exposed adults: over 80 published articles on TCE’s

carcinogenicity to humans, more than 20 reports on occupationally exposed groups, 40

case-control studies and more than a dozen community-based studies (Watenberg et al.

2000). The most common effects from TCE inhalation exposure include neurotoxicity,

heptatoxicity and nephrotoxicity. Reproductive and developmental toxicity have been

extensively studied, with largely negative results (Barton et al. 1996). Chemically

induced genetic mutation inducing tumors in humans does not appear to be caused by

TCE or its metabolites. This is because very high levels of TCE are required to cause

genotoxicity (Moore and Harrington-Brock 2000). Liver and lung tumors and

lymphomas have been reported in mice inhalation studies (Watenberg 2000).

Humans occupationally exposed to TCE have increased incidence of liver,

kidney, and cervical cancers, as well as non-Hodgkin’s Lymphoma, Hodgkin’s disease

26

and multiple myeloma (Wartenberg et al. 2000), though these concentrations are many

orders of magnitude higher than air in homes measured on the South Hill. A study by

Axelson et al. (1994), found no evidence that trichloroethylene was a human carcinogen

for an average occupational inhalation exposure level of 20,000 ppbv when studying

inhalation effects in 1,424 men and 249 women from 1955 until 1987. This is because

average cancer rates were lower than expected. Some other effects of TCE inhalation

exposure are neurological, liver and kidney effects (Barton and Clewell III 2000). Ertle

et al. (1972) reported “psycho-organic syndrome”, characterized as unrest, generalized

fatigue, disturbed vision and neurological aberrations, to be caused by exposure to TCE.

Headaches, sleepiness, fatigue and/or drowsiness have occurred at approximately

100,000 ppbv and are characteristic of neurological toxicity (Barton and Clewell III 2000,

Barton and Das 1996). Headache (27,000 ppbv) and drowsiness (81,000 ppbv) occurred

in human volunteers exposed to TCE for 1-4 hours (Nomiyama and Nomiyama 1977).

One study on low level occupational exposure (average 6,000 ppbv) found that TCE had

negative effects on the immune system (Iavicoli 2005).

Information on toxicological effects on the order of magnitude of those on the

South Hill of Ithaca (i.e. at the ppb range) was difficult to obtain for inhalation exposures.

There is still a significant gap in the scientific knowledge on what the long term

consequences could be. However, information on the toxicological effects from oral

exposure (due to contaminated drinking water wells) was available at lower doses.

Residents in Wobum, Massachusetts had increased adverse effects on the immune system

causing increased risk to respiratory infections (asthma, bronchitis, and pneumonia) and

increased cases of leukemia in children orally exposed to 267 ppb of TCE between 1971

27

and 1979 (Byers et al. 1988). Three hundred sixty two individuals exposed to 6 to 500

ppb of TCE and other chemicals through drinking water wells in Tuscon, Arizona found

increased frequencies of 10 systemic lupus erythematosus symptoms, arthritis, Raynaud’s

phenomenon, malar rash, skin lesions related to sun exposure, seizure or convulsions, and

mood disorders, as well as decreased blink reflex, eye closure, choice reaction time, and

intelligence test scores (Kilbum and Warshaw 1992, 1993). A study of 80,938 births and

594 fetal deaths in New Jersey linked with contaminated drinking water (>10ppb TCE)

found an association with oral clefts, central nervous system defects, neural tube defects,

and major cardiac defects (Bove et al. 1995).

TCE Metabolism

TCE inhaled will either be exhaled before being absorbed into the bloodstream by

tissues, or metabolized and excreted through the urinary tract (Dobrev et al. 2002).

Toxicological effects of TCE are largely due to the metabolites, including

trichloroacetaldehyde, chloral hydrate, dichloroacetate, trichloroacetate, trichloroethanol

and trichloroethanol-glucuronide (Barton et al. 1996). Other parent compounds that

produce the same metabolites are tetrachloroethylene (PERC), methyl chloroform (MC),

1,1,1,2-tetrachloroethane, cis-1,2-dichloroethylene, trans-1,2-dichloroethylene, 1,2-

dichloroethylene and 1,1-dichloroethane (Wu and Schaum 2000). Exposures to TCE,

PERC and MC simultaneously at their respective time-weighted average threshold limit

values, has been shown to result in elevated (22% increase) TCE blood levels compared

with individual chemical exposures (Dobrev et al. 2001). The reason kidney and liver

cancer are the most common cancers associated with TCE exposure is because of

metabolites. There are two major pathways of TCE metabolism in the body, one

28

involving oxidation with cytochrome P450s and the other is conjugation with glutathione

(Lash et al. 2000). Cytochrome P450s are very versatile enzymes, found in high

concentrations in the liver (86% of the body’s P450s), which can perform a host of

reactions. However, in the case of TCE degradation, the metabolites produced in the

liver are carcinogenic. These metabolites include chloral hydrate, trichloroacetate, and

dichloroacetate (Lash et al. 2000). The second major pathway of TCE metabolism is

glutathione conjugation, in which glutathione, a peptide of amino acids, is attached to

TCE. This primes it for urinary excretion. However, metabolites that occur in the

kidneys from this conjugation have been associated with kidney cancer. The P450

pathway has higher activity and affinity than glutathione conjugation (Lash et al. 2000).

Behaviors that can increase the risks of cancer from TCE exposure include

alcohol consumption and smoking. Alcohol can interfere with TCE excretion and

metabolism, increasing the formation of trichloroethanol, a metabolite also associated

with cancer. Individuals who consume alcohol may be in a particularly sensitive

population (Barton et al. 1996). Smoking may also increase the risk of genotoxic effects

from TCE exposure (Seiji et al. 1990). Mothers who are breast-feeding should also be

aware that TCE could accumulate in breast milk (noted earlier). With regards to TCE

toxicity, it is most important to note that there are significant gaps in the scientific

knowledge of long-term low-level exposures. This is largely due to the difficulty in

finding a human population not exposed to low levels of TCE against which exposed

groups can be compared.

29

Section 3: Economic Analysis Ian Toevs

The potential impact of an environmental contamination problem almost always

extends beyond health and peace of mind. Often an economic component is involved.

The situation on South Hill is no different; in fact, these issues are very closely related.

However, it is unclear how substantial their impacts may be. Possible economic burdens

the on the homeowners include a lowering of real estate values and the cost of operating a

mitigation system. A proactive sampling and mitigation strategy by Emerson could help

reduce their overall cleanup expenses while easing the anxiety of the affected residents.

Real Estate Value

Through the assistance of Kathy Hopkins, a real estate agent of Audrey Edelman

& Associates, and Jay Franklin, from the Tompkins County Department of Assessment,

insight was gained regarding the current behavior of the South Hill real estate market. In

order to address a fluctuation in real estate values, the record of sales and assessed values

were examined. May 2004 was the first public meeting in which the South Hill

contamination issue resurfaced. From May 2004 to April 2006, there were 22 houses

sold directly in, or bordering, the study area. Of these transactions the average selling

price was $150,180. On average, this is 26% higher than the corresponding assessment

values. Similar data were compared for the greater South Hill area as well as for all of

Ithaca. From 2003 to 2005 the average increase of selling price to assessed value for

houses in the greater South Hill area was 38.9% while for all of Ithaca it was 30.3%.

From 2004-2005 the increase for South Hill was only 19.6%. However, this must be

compared with the same time period for Ithaca, which only had an increase of 6.3%.

This shows that the housing values have increased at South Hill in parallel to the trend for

30

the rest of Ithaca. Although this is a relatively small sample size over slightly less than

two years, there is no quantitative indication that the selling prices for homes on South

Hill have shown any negative trends to April 2006.

An additional impact that is less obvious in sales and assessment data is the

amount of time that houses are on the market and the number of bids received for a sale.

Those who live in Ithaca and have had any exposure to the real estate market know that it

is extremely active. As a result, it is not uncommon for a house to be on the market for a

matter of weeks or less and receive numerous bids. Anecdotal evidence from home-

owners in the South Hill area have indicated that following the May 2004 rebirth of the

TCE contamination issue, houses have remained on the market longer and have seen

significantly fewer potentially interested buyers. An article in the Ithaca Journal (Daley

2005) provides support for this perception. Ultimately, the amount of information known

about the extent of the pollution problem will play a substantial role in the buyers’

purchasing decision. New discoveries, either positive or negative, may influence the

behavior of the South Hill housing market, and according to the Tompkins County

Department of Assessment, the situation is under close monitoring, and assessment

values will be adjusted if a trend is identified.

Mitigation Operating Cost

Currently, the most effective method known for alleviating the threat of indoor

vapor intrusion is the installation of a suction system (essentially identical to a radon

mitigation system) that removes the air from below the concrete slab of the mitigated

house and vents it into the atmosphere. Emerson has agreed to cover the costs associated

with the mitigation system installation, maintenance, and repair. However, another

31

potential expense that must be accounted for by either the homeowner or Emerson is the

cost of powering the mitigation exhaust fans, which must run continuously. Fantech lists

fans rated from 13-248 watts. Assuming energy costs of $0.12 per kilowatt-hour, the cost

to operate one fan ranges from $13 to $260 per year. Some mitigation systems may

require the use of two fans or a high suction fan rated up to 320 watts. As currently

advertised from Infiltec, this system would cost up to $336 annually. These costs, over

the lifetime of a house, are quite significant and as energy costs continue to rise, they will

increase.

Another point is important to make. Mitigation cannot just consist of “pumping

under the slab” because this will be ineffective unless the macro and micro-integrity of

the floor and walls is assured. The surface should be sealed with an epoxy paint, and

connections between the slab and outside (sumps, French drains and the like) need to be

severed. Perhaps 50% of the residences on South Hill lack complete slabs. Laying

complete slabs and sealing properly the walls of basements could cost $10’s of

thousands of dollars per residence. On the positive side, the needed mitigation will

provide drier basements with increased livability, and add to the value of the property.

Would property owners be willing to allow such major renovations that might have other

code implications? Are such renovations feasible in all the houses that might be

affected? These are major facets of mitigation that will need to be addressed.

Overall Economic Analysis

The effectiveness and success of Emerson’s strategy for mitigating harmful

effects from the contamination on South Hill can be measured in many ways. The

primary objective, of course, is to quickly reduce the exposure of people to the

32

contaminants in order to prevent further exposure. A secondary issue is to do so in an

economical manner. A strategy that could address both of these issues is to offer a

universal mitigation approach to all who live in the area of contamination. Unfortunately

there has not yet been a clean perimeter established. As a result, the present strategy is to

test for volatile organic compounds (VOCs) while expanding the perimeter and retesting

in an attempt to delineate the boundary of contamination. There are many problems with

this strategy:

1. This practice is very time consuming (the delay between sampling and receiving

test results is typically 8 to 12 weeks). This is exasperated by the fact that testing

is only performed during the heating season (late fall through early spring).

2. As discussed later in this report, there is high variability in TCE transport

processes, so the test results may falsely show no detection.

3. Related to (2), the current standard of installing mitigation systems only for

residences that have detectable levels of TCE in the indoor air is inadequate. It is

not known how long the concrete will act as an effective barrier.

4. Testing for TCE and other VOCs in a certified lab costs approximately $800 per

sample. Each house typically has three or four samples taken for one round of

sampling, assuming the house is of the proper construction to obtain the necessary

samples. Some of the houses currently under observation are on the third round

of sampling which brings the cost per house to a maximum of $9600. According

to the U.S. Environmental Protection Agency the general cost to install a radon

mitigation system (which is essentially identical to a TCE mitigation system)

ranges from $800 to $2500 with an average of $1200

33

(http://www.epa.gov/radon/pubs/consguid.html). Although follow-up testing is

required to verify that the system is working effectively, a mitigation system and a

round of follow-up testing is approximately equal to two rounds of initial testing.

Either strategy for mitigation should include continued follow-up monitoring for

VOCs. It is also necessary to note that many of the houses in the South Hill area

would cost much more than the average mitigation expenses listed here due to

many influences, including: a dirt floor basement or a partial concrete slab, houses

constructed directly on top of solid rock, or extremely permeable foundations

such as a laid-up stone wall. A worst-case scenario for the extent of the

contamination plume (Figure 3-1) would include approximately 375 properties

beyond what has already been tested. Assuming the maximum typical price

($2500 per system), the cost of mitigation and one round of follow-up sampling

would be approximately $2.1 million. In comparison, the price of running 2

phases of sampling on all houses would cost $2.4 million plus the cost of the

mitigation systems and follow-up testing that would be required based on the

sampling results. These prices are approximately equal. However, the blanket

mitigation approach would provide additional benefits to the residents by

providing a sense of assurance and improve Emerson's public relations.

34

Figure 3-1: Worst case scenario of contaminated area.

Conclusions

• Fortunately at this time there has not been evidence of a significant economic

impact on the residents of South Hill; however, it is unknown whether this will

happen in the future.

• A concern still remains about the cost of operation for the mitigation systems.

While most systems will not be unduly expensive to run, increasing energy costs

will increase the expense.

35

• One of the main concerns is the amount of time that is spent in determining who

is eligible to receive a mitigation system. Based on the rough calculations of total

expenses to Emerson and the intrinsic benefit of having a supportive group of

community members, it could be mutually beneficial to Emerson and community

members to offer a wide scale blanket mitigation scheme.

36

Section 4: Geology Rachel Shannon

The geology on South Hill is an important factor which influences the direction

and speed with which water and contaminants can move through the ground. This section

includes a short description of the geology of the area, as well as some suggestions for

the role that geology may play in the movement of contaminants.

Figure 4-1 is a diagram of a hypothetical slice of the subsurface, built for this

paper from information in “Groundwater Evaluation of Remediation Area, Emerson

Power Transmission Facility Ithaca, New York,” a report prepared by ESC and received

at Tompkins County Public Library on March 18 2005. This report concludes that the

geology in the area can be divided into four distinct zones. Zone A is glacial till (a type

of soil deposited by retreating glaciers- see glossary), and is about 5-10 feet thick in most

places in the area. According to the report cited above, the glacial till in the South Hill

area is mostly clay, but there are small amounts of gravel mixed in. The till could be

permeable where the gravel content is high. Below the glacial till, the bedrock is

siltstone. All of the siltstone is fractured, but the extent of the fracturing depends on the

depth. Therefore, the siltstone is divided into three separate zones based on how

fractured the rock is. Zone B is directly under the glacial till and reaches a maximum

depth of 22 feet below the surface. It is highly weathered and fractured. Zone C starts at

the base of zone B and reaches a maximum depth of about 55 feet below the surface,

showing less fracturing than zone B. Zone D starts at the base of zone C and reaches a

maximum depth of 145 feet. The rock in zone D has much fewer fractures that are more

widely spaced.

37

In the Ithaca area, the bedrock fractures, called "joints", are generally evenly

spaced and perpendicular to each other in all three dimensions. This seems to hold true on

South Hill. The first set of fractures runs approximately north-south, the second set runs

approximately east-west, and the third set runs horizontally. The result is that the bedrock

is cut into blocks, and each block is surrounded on all sides by fractures (Figure 4-2).

Openings along the fractures vary in size; large openings are inches wide, while the

smaller ones can be less than a millimeter wide. Because most of these fractures are deep

underground, it is impossible to estimate where exactly all the fractures occur, or even

Figure 4-1: Diagram of a hypothetical slice through South Hill. Layer A is glacial till with a variable low to very low permeability. Some water will infiltrate through this layer. Layer B is weathered and fractured bedrock of moderate to low permeability. Layer C is an "intermediate" zone; it is less fractured and less permeable than layer B. Layer D is much less fractured than the layers above it, and as a result it is probably much less permeable. Section constructed from “Groundwater Evaluation of Remediation Area, Emerson Power Transmission Facility Ithaca, New York,” an ESC report received at Tompkins County Public Library on March 18 2005

38

how many there are. On the West Spencer Street road cut, fractures can be seen every

few feet.

Following are a few observations/ideas from a geologic perspective. The role the

fractures may be playing is discussed in more detail in Section 7.

• The rainwater that does not run off into sewer drains flows downward through the

uppermost layer of glacial till into the siltstone bedrock layers.

• Fractures in the bedrock can either act as water conduits or as barriers. If they are

open, water can flow through them very quickly. However, often fractures get

filled up with clay and silt from the soil. In those cases, fractures may actually

stop the water and cause it to be stored in the rock. It is possible that both

Figure 4-2: Schematic drawing of rock joints. The rock is divided into blocks, and each block is surrounded by fractures on all sides. The fractures could provide pathways through which water can flow.

39

scenarios are true on South Hill: some fractures are conducting water while others

are blocking it.

• Siltstone itself is fairly impermeable to water. Therefore, water flows through the

fractures in the rock.

• Variations in the fracturing of the bedrock will produce variations in permeability

and cause the depth of the water table to vary, perhaps greatly, from location to

location.

• If water moving through a particular chain of fractures encounters a liquid puddle

of TCE, the TCE can dissolve in the water and be carried to a basement if the

fracture chain intersects a house. A different fracture path intersecting a

neighboring house may not have encountered TCE and the basement of this house

may therefore, even though damp, be free of TCE contamination. The fractured

nature of the bedrock at South Hill makes the transport of TCE and contamination

of the basement of houses much more complex.

40

Section 5: Hydrology Brianne Smith and Adrian Harpold

General information about water transport through the subsurface

To gain an understanding of TCE transport mechanisms, knowledge of

groundwater and water balances must first be attained. This is, perhaps, most easily

explained with the use of a diagram:

The water cycle begins with evaporation (E) from a lake or from the ground or by

transpiration (T) from plants; the combined process is called evapotranspiration (ET).

The amount of water that evaporates or transpires varies depending on atmospheric

factors, plant type and degree of saturation of the soil. The water comes back into contact

with the soil as precipitation (P). Upon contact with the ground, it will either saturate the

soil or, if the soil is already saturated, it will flow over the land as overland flow (O),

commonly called "runoff". The water that saturates the soil has a similar fate; it can flow

Figure 5-1: Water transport mechanisms.

41

through the top layer of soil as interflow (I), or it can continue to move down through the

soil as recharge (R). The amount of water that moves as interflow can be determined

using the slope of the surface as well as the depth of the saturated layer and the ease with

which the water moves through the soil. The recharge will move vertically downward

under the force of gravity until it reaches an impermeable layer and saturates (fills 100%

of the pores), forming a perched water table. The groundwater can then travel

horizontally as interflow. At some depth the ground becomes saturated everywhere.

This is called the water table. Below the water table water may move horizontally as

base flow (B). Base flow will always move in a direction from higher hydraulic head to

lower hydraulic head with a speed determined by the magnitude of the head difference

and the permeability of the rock or soil. The hydraulic head is the elevation (above sea

level) or water in a well. Scientifically these head-measuring wells are called

piezometers, which are long tubes with small holes in the bottom that are buried in the

ground to the depth of interest. The elevation of the water in the piezometer tube is the

head of the water. Water will flow from an area with a higher piezometer water height to

an area with a lower piezometer water height.

A water balance may be done on an area of soil by setting the sum of all above

water fluxes equal to the change is storage of water within the soil (S). So for an area of

soil spanning from the ground level to the top of the water table, a water balance would

be equated by the following:

S = P – ET + Oin – Oout + Iin – Iout – R

The groundwater situation for South Hill is a more complicated version of the

diagram shown above. One complication is that much of the South Hill area is made of

42

fractured rock. The rock itself is relatively impermeable but water can rapidly flow

through fractures in the rock. The glacial till above this fractured rock is not very thick.

Springs or seeps occur groundwater table or a perched water table is intersected by the

ground surface. This results in wet spots and possibly in water flowing out of the ground.

Wet spots on the side of a hill may indicate perched water tables.

Physical controls on groundwater movement at South Hill

As explained in the previous section, groundwater movement is complex and

difficult to measure in the best case. At the South Hill in Ithaca, groundwater movement

is complicated by a very heterogeneous (many different types of materials and properties)

geology and human disturbances above and below ground. This section of the report

seeks to explain the major controls on groundwater movement at South Hill and identify

important possible pathways for TCE transport in the subsurface.

Figure 5-2: Water transport: seeps and springs.

43

Geologic and Soil Controls on Groundwater Movement

At the South Hill site, groundwater occurs in both the top layer (fill and glacial till

material) and in the fractured bedrock below (see Geology Section). However, some of

the monitoring wells installed did not encounter a groundwater table, and in other places

the ground water table varied in elevation in an erratic (anomalous fashion). The well

measurements indicate a clear hydraulic connection between the topsoil and bedrock.

This means that water (and TCE) can be transmitted through the till layer to the bedrock.

A rising water table can move TCE from the bedrock into the till. Movement of water in

the till can be estimated with some accuracy. However, water flow in the bedrock is

controlled by fractures in the rock and the size, length, and interconnection between

fractures. The complexity of movement in the bedrock makes estimating detailed

groundwater movement nearly impossible at South Hill.

Water table measurements were made in 1987, 1988, 1989, and 2003. The

measurements show that the groundwater is moving northeast to northwest depending on

the exact location on the hillslope. The direction of movement is generally in the

direction of the declining hillslope moving north (northeast) of the Emerson plant.

Unfortunately, the measurements made are incomplete in several ways. First, there are

numerous anomalies in the measurements. This is due to the complex geologic controls

in the fracture bedrock that we discussed in the previous section. Unfortunately, this

makes measurements from the deep wells (into the bedrock) unreliable indicators of the

directions of ground water and contaminant flow. Another issue with the groundwater

measurements is that three of the measurements were made between September and

November. Typically, this time of year has the lowest water table levels. The data allow

44

very little to be said about the seasonal movements of the groundwater table. Five wells

were measured in May 1987 and results are shown in Figure 5-3. Site MW-3-13 is the

only well screened from the topsoil, which was almost two feet higher in the spring. All

but one of the wells show higher levels in the spring compared to fall, as expected. The

fluctuation of the groundwater in the topsoil is an important transport process for TCE

(explained subsequently).

Figure 5-3: Water table heights for five measuring wells located near the fire reservoir. Water levels are higher in the spring than fall. Additionally, the well in the topsoil shows a more significant variation in water height, which is important for TCE transport.

An electrical resistivity (ER) test was performed in July 2005 to assess the

subsurface hydrogeology at South Hill (ESC 2005). The results of the test show a

complex pattern in electrical conductivity (Figure 5-4). The survey is purported by the

Ground Water Depths

0

5

10

15

20

25

MW-1 MW-2 MW-3-13 Soil MW-3-31 MW-4 Well Number

Depth to GW (ft)

May 1987 October 1988 September 1989 November 2003

45

company that made the measurements to suggest patterns of groundwater flow, but these

suggestions are very preliminary and have no independent verification.

Figure 5-4: Electrical Resistivity results for South Hill moving in a Southwest direction. Red boxes indicate saturate areas at the surface and deeper into the subsurface. Note the low resistivity (blue) near the surface appears to connect to deeper areas (red box). Source: ESC, Geophysical Survey Investigation. 10/31/05.

During the site assessment, rising and falling head well tests were used to estimate

the hydraulic conductivity (the permeability to ground water flow) of the subsurface. The

permeability (hydraulic conductivity) of the soil and bedrock decreases with depth. A

trend in reduced permeability is consistent with boreholes, core logging, and geologic

mapping at South Hill. The permeability ranges from 1.6 X 10-4 cm/sec (moderate) to 4.4

X 10-7 cm/sec (low) in the shallow bedrock. The permeability is slightly less in the deep

bedrock, ranging from 1.5 X 10-6 to 1.9 X 10-7 (Radian, 1987). As expected, the deeper

bedrock is less permeable than the more fractured shallow bedrock.

Human Induced Transport Mechanisms

Human activities on South Hill such as paving, removal and filling of topsoil,

installation of subsurface pipes, and artificial control of the canal leading to Cayuga Lake

have changed possible TCE transport pathways. .

46

Development on the South Hill has led to a significant portion of the area being

either paved or put under the footprint of a building. The pavement has had severe

impacts on water transport issues. First, the hillside is subject to less groundwater

recharge because more water moves over streets and into sewers. This likely means that

groundwater levels fluctuate less and there is less groundwater moving through the

system. In the steeper sections of South Hill the residential housing has been built into

the hillside. Change in grade (from steep to flat) will often cause the groundwater to

come closer to the surface. Unfortunately, basements and crawlspaces can often become

damp as a result, and the water seeping into them can introduce TCE if TCE is dissolved

in it. For example, the garage shown in Figure 5-5 was built into the hillside and seeps

groundwater in an area contaminated with TCE.

Figure 5-5: Garage where water can be transported through a wall built in the topsoil. White pipe in top-right corner drains water outside. Photograph by Regina Deschere.

47

There have been significant alterations to the soil on South Hill that can directly

affect water transport. Large pipes going down steep grades often have water moving

through the disturbed/filled zones adjacent to the pipes. Additionally, the houses all have

individual utility pipes. Pipes were found in the ground penetrating radar (GPR) survey

we performed in the Spring 2006. These unnatural conduits could transport vapor and/or

water with dissolved TCE, and will be discussed in the next section.

Conclusions

Groundwater in the glacial till and the fractured bedrock moves towards the

northwest, propelled by gradients in hydraulic head that are often very steep.

The water table fluctuates in both the bedrock and topsoil depending on rainfall.

Water tables are highest in the spring.

Groundwater flow in the bedrock is controlled by fractures. Despite low

hydraulic conductivities reported, rapid movement of water is expected in the

fractures.

Well tests and an electrical resistivity survey suggest that water will flow through

the glacial till into the bedrock.

Human activity has influenced the pathways for water and TCE on South Hill.

These influences include: increases in asphalt, removal and filling of topsoil, and

installation of subsurface pipes.

The total amount of groundwater flow in the subsurface is small and therefore

TCE movement in the vertical direction likely dominates over lateral movement.

48

Section 6: Spring Water and Basement Air Sampling Veronica Morales and Rachel Dunn

Chemical analysis of water and air samples is fundamental to understanding TCE

transport and risk in South Hill. Current analyses are expensive and are conducted

sparingly. This section details methods that might allow samples to be analyzed less

expensively and also sets forth sampling plans.

Spring Water Sampling

The identification of dissolved TCE or its degradation daughter products in spring

water could provide evidence of possible DNAPL sources upstream of the spring. Due to

the proximity of the homes to springs, dissolved TCE in the spring water may also be

indicative of possible intrusions of contaminated water into the homes, and/or presence of

volatilized TCE in the unsaturated soil that envelops nearby basements. Although spring

water sampling in the past had non-detectable concentrations of TCE, it is important to

continue monitoring this potential contaminant pathway.

A. Identified Springs

i. 100 block of S. Hill Terrace -spring sometimes visible from the street

ii. Hillview Park -center of park, South of the “Acropolis Cooperative” apartment building

iii. End of 100 block of S. Hill Terrace -water drips out of rocks in the back of the house and periodically from a large open rock in the driveway wall

iv. 100 block of E. Spencer St. -weepy outcropping

v. 200 block of W. Spencer St. -weepy outcropping

vi. 600 block of S. Cayuga St. -plant treated effluent water running parallel to the east side of the street

B. Sampling Strategy

49

Our spring water sampling strategy consists of collecting and analyzing duplicate

water samples from identified springs while they are active. Collaboration with

homeowners should be established to monitor the springs and determine appropriate

timing for each sampling event. Analysis of the collected samples could be done in a

qualitative way, as the concentration of dissolved TCE will undoubtedly be lower in the

exposed spring water than in the unexposed ground water. This weakened concentration

is attributed to the ambient contact and agitation of spring water as it emerges from its

source, increasing the chances of TCE volatilization from its dissolved state. The

sampling period is intended to last from the time the water starts to flow until water yield

from springs is exhausted for the season, and sample collection should initially be done

with a frequency similar to that of basement air sampling.

C. Sampling Method

NEMI Method 524.2 - VOCs in Water Using GC/MS

Measurement of Purgeable Organic Compounds in Water by Capillary Column Gas Chromatography/Mass Spectrometry Sources: U.S. EPA National Exposure Research Laboratory (NERL) Microbiological and Chemical Exposure Assessment Research Division (MCEARD)

The methodology selected calls for the utilization of 40 mL of pre-acidified glass

bottles to collect the liquid samples. The amount of acid should be approximately 2 drops

of 1:1 HCl to adjust the water pH to less than 2. This will prevent further degradation of

the compound of interest until time of analysis. All samples should be collected in

duplicate, minimizing agitation of the water as it enters the sample bottle. The bottles

should be overfilled with no bubbles or headspace and capped tight so as to not lose the

sample during storage time. The lid or septum used to cap the bottles should not be made

50

of silicon as this material absorbs volatile compounds. Teflon is a recommended material

when TCE is the compound of interest. Samples should be stored at less than 4oC (38oF)

until analysis.

D. Method of Analysis

NEMI Method 524.2 is applicable for VOC concentration ranges of 0.02-200μg/L.

From Section 2, concentration greater than about 1 μg/L may be of concern. For this

particular method, an inert gas is bubbled through a water sample to purge volatile

organic chemicals into the container’s headspace. Once in the gas phase, the compounds

are trapped in a tube containing a suitable sorbent material (typically use a specific type

of activated charcoal for the detection range desired) in order to concentrate them. The

tube with concentrated and adsorbed VOCs is then heated to desorb the trapped

compounds and is then directly injected to the Gas Chromatograph where they are

analyzed.

E. Discussion

At a meeting in April with Cornell students, the DEC expressed interest in collecting

data from spring water samples. Proper documentation and permission to enter residents’

property is a time consuming and required procedure that the department would need to

obtain in order to collect this data themselves. Due to the heavy workload and time

constraints of the DEC, spring water sampling has been postponed for its time-consuming

preparation work, which they currently are not able to contend with. Cornell students on

the other hand have the advantage of requiring only informal permission from

homeowners to enter and collect such samples in private property. During the earlier

weeks of the spring semester 2006, Mr. Carl Cuipylo (DEC geologist) had proposed

51

collaborative work with the TCE student group for sampling South Hill’s springs. He

proposed to provide the sampling equipment and have his laboratory perform the analysis

if Cornell students took it upon themselves to obtain permission from homeowners and

collected the water samples. Unfortunately, this arrangement could not be worked out for

the Spring 2006 semester.

F. Recommendations

Since some of the analytical equipment on campus was unavailable to conduct these

tests due to time and monetary constraints, the sampling of water was omitted for this

semester’s project. It would be advantageous to have the DEC reconsider working with

students to accomplish the sampling of springs in the future and have their laboratories

analyze the samples formally.

If in the future, students were to conduct water sampling and analysis, the thermal

desorber method may be exchanged with the solvent method presented in the following

section for analyzing air samples. This method consists of using carbon disulfide as a

solvent to desorb the concentrated compounds from the sample tube rather than heat.

Basement Air Sampling

Community members of South Hill have expressed strong concerns regarding the

biannual sampling strategy used to determine the toxicity levels of TCE in their homes.

Since the irregular sampling procedure from Emerson’s consulting company determines

which homes are eligible to receive mitigation as remediation action, South Hill residents

wish to confirm that the few samples collected are justifiable averages of the indoor

conditions within their homes. This matter beckoned the need for the development of a

sampling approach that would better account for time variations and could be extended

52

beyond the currently used temporal boundaries. Because of the limited financial

resources that Cornell students had available for this project, it was not possible to

undertake the expense of hiring a consulting firm to perform the necessary professional

analysis at the cost of $800 per sample. As an alternative, a more economic but still

official sampling and analytical procedure was selected that could be performed by

students using campus equipment.

A. Sampling Strategy

It is important to determine how well a single sample represents the long-term air

concentration of TCE in the basements of the community members. In order to

accomplish this, we propose that three to five houses with TCE indoor concentrations

close to the 5μg/m3 (1 ppbv) limit (The NYSDOE limit for indoor air, see Section 2)

and/or very high sub-slab concentrations be tested repeatedly over a period of several

weeks or months. The data from such samples would ideally provide some insight on the

variability of TCE concentrations over pre-established time intervals. The results could

then be used to determine weekly, monthly or seasonal trends. For shorter time intervals,

the results could be correlated to changing weather conditions such as precipitation and

temperature. Correlation to meteorologic and geologic/ground water observations should

be attempted. Determining correlations with outdoor temperature, barometric pressure,

rainfall, and the like could help establish optimum sampling conditions for indoor air

sampling of TCE. At present, indoor vapor sampling is conducted during the fall/winter

season because homes tend to have the windows closed, thus trapping intruded TCE

within the home. Most importantly, the results of the proposed detailed sampling and

53

analysis could confirm or refute that homes classified as ‘No Further Action’ are

truthfully out of risk.

Once this methodology is tested, and we are confident we can reliably measure TCE

levels in a house, samples from houses never tested could be taken, and the perimeter of

the affected area on South Hill determined more quickly and more cost effectively than is

possible under the current DEC/Emerson procedures. Additionally, because the

presented sampling methods do not require a particular type of slab or a degree of

basement sealant, these tests could theoretically be done in any basement with typical

humidity, and airflow conditions. Collected data will initially be analyzed for the

following parameters:

a. Time variations b. Spatial analysis c. Ground water level variations

B. Sampling Method

Three general methods of sampling were identified in this preliminary investigation:

1. Vacuum tube 2. Passive diffusion onto sorbent 3. Active sampling with sorbent The vacuum tube method is the simplest. Here a tube is evacuated, sealed,

opened in the air of interest, sealed again, and then taken to the lab for analysis. The

problem with this method is that the TCE in the sample taken is only as concentrated as

the TCE in the air, which is in our case below the detection limit of most widely used

analytical instruments. In addition, this method only provides a snapshot of the TCE

concentration of air in one location and at an instant of time, which might not be

representative of true average (over time) basement concentrations.

54

Sampling onto a sorbent material concentrates the compound of interest and

accumulates the sample over a protracted period. If the passive diffusion method is used,

then a certain amount of sorbent is passively exposed to the air of interest for a

predetermined period of time (see Figure 6-1 for passive diffusion sampler). If the active

sampling method is used, a pump is used to push air through the sorbent medium at a

constant rate, allowing a large volume of basement air to come into contact with the

sorbent material. The larger air volume that is exposed with the active sampling method

will theoretically provide a more realistic average (over time) of the entire room’s

contaminant concentration.

Figure 6-1: SKC Passive diffusion sampler for organic vapors. <http://www.skcinc.com/prod/575-001.asp> In order for any of these sampling methods to be effective, the concentration

collected must fall within the detection limits of the analytical instrument at hand.

Summaries of three methodologies developed by the Environmental Protection Agency

(EPA) and the National Institute of Occupational Health and Safety (NIOSH) are given

below. Full methodologies can be found at the websites in Appendix D.

55

EPA TO-15 EPA TO-15 Compendium of Methods for the Determination of Toxic Organic Compounds in Ambient Air: Determination of Volatile Organic Compounds (VOC) In Air Collected In Specially Prepared Canisters and Analyzed By Gas Chromatography/Mass Spectroscopy (GC/MS)

The EPA method TO-15 can be used to detect VOC concentrations above

0.5ppbv (parts per billion in volume) in ambient air. The method requires the use of

vacuumed sampling canisters for sample collection. A known sample volume is removed

from the canister and injected into a GC/MS system. However, in order to achieve the

necessary sensitivity, the GC/MS must also have a sampling/concentrator system, which

allows a more concentrated volume of VOCs to pass through the detector.

EPA TO-17

EPA TO-17 Compendium of Methods for the Determination of Toxic Organic Compounds in Ambient Air: Determination of VOCs in Ambient Air Using Active Sampling Onto Sorbent Tubes

This method can be used to measure VOC concentrations in ambient air between

0.5 and 25 ppbv. Samples are collected using a suction pump that draws air into a

thermal desorption sampling tube (see Table 6-1 for EPA recommended sorbent

materials) where the desired analyte is concentrated. The sample is analyzed using a

GC/MS unit (or a GC with a combination FID/ECD detector system). In order to remove

the VOCs from the sorbent, the GC must also have a two-stage thermal desorption unit.

The first unit heats the sorbent, releasing the VOCs in the sample. The secondary trap

unit traps and concentrates the sample once more for analysis by the GC/MS system.

This method is intended to detect between 27,000 and 875,000 ppbv in a 3.4-L air

sample. This method uses a suction pump (in our case, calibrated and reversed fish

aeration pumps were used) and sorbent tubes to collect the sample (see Figures 6-2 for

56

Table 6-1: EPA recommended sorbent materials.

Sorbent Strength Surface Area per gram Of Sorbent (m2/g)

Type of Sorbent

Weak < 50 Tenax® Carbopack TM/trap C Anasorb® GCB2

Medium strength 100-500 Carbopack TM/trap B Anasorb ® GCB1 All Porapacks and Chromasorbs

Strong 1000 Spherocarb ® Carbosieve TM S-II Carboxen TM 1000 Anasorb ® CMS series sorbents

NIOSH 1022

NIOSH Manual of Analytical Methods Method 1022: Determination of Trichloroethylene Using Sorbent Tubes, GC/FID, and CS2

active sampling set-up). Once the sampling period is over, the TCE is removed

from the sorbent material u--sing a solvent (carbon disulfide CS2) instead of the thermal

desorption unit used for the previous two methods. The extracted CS2/TCE solution can

then be injected directly into a GC unit with a flame ionization detector (FID) for

analysis.

Figure 6-2: Active sampling set-up.

57

A representative from SKC, the distributor of the sorbent tubes purchased for this

project, indicated that increasing the time over which the sample is taken and/or placing

sorbent tubes in series may lower the detection limit of this method. SKC strongly

discourages increasing the airflow rate as an unsafe alternative to decrease the detection

limit of the tubes, given that the higher airflow pressure may cause the glass tubes to

break.

C. Method of Analysis

After the collection period is over, the sorption tubes are removed from the sampling

set up, capped on both open sides, labeled, and packed securely for shipment to an

analytical laboratory. Once ready for analysis, the sorbent sections of each sample are

carefully pushed out of the glass tube and placed in individual 2 mL glass vials. Here 1

mL of carbon disulfide sorbent is added and the vials capped tightly. The sample is

allowed to stand for 30 minutes with occasional agitation. During this waiting period, the

gas chromatograph is set to pre-established operating parameters. A microliter syringe is

used to inject approximately 2 μL of the CS2 /TCE solution into the GC/FID for analysis,

and the mass of TCE found in the sample is calculated with an equation provided in

method 1022 from peak heights in the chromatogram. The chromatogram in Figure 6-3

shows the peaks expected for carbon disulfide and TCE at 4.29 and 9.18 minutes

respectively.

58

Figure 6-3: Chromatogram (carbon disulfide and TCE peaks).

D. Results & Discussion

The Civil and Environmental Engineering (CEE) and Microbiology departments were

approached to inquire about available instruments already set up for TCE analysis. The

CEE department indicated that several GC units could be made available, but none had a

detection limit low enough for the air samples of interest. Although one GC with an

electron capture detector (ECD) was stored in the basement, no one knew of its current

functionality since it had been out of use and disassembled for several years.

Dr. Eugene Madsen from the Microbiology department had both a GC/FID and a

GC/MS unit accessible to our group. However, no lab on campus had a thermal

desorption unit. Because of this we decided to gain experience with the NIOSH 1022

method. To distinguish between the mass of TCE and CS2 in the sample, it was found

necessary to modify the computer program that analyzes the chromatogram. The

59

parameters were changed with the aid of a skilled chromatographer, and the new program

saved for future use in the Microbiology laboratory.

New operating parameters:

Temperature injection (deg C) 53 Isothermic time (min) 6.0 Ramp rate (deg C/min) 20 Ramp max temp (deg C) 200 Isothermic time #2 (min) 0.5 Total run time (min) 13.85

Regrettably, mass balance calculations around the new sorbent tube mass and

extended sampling times showed that even with basement concentrations at the EPA’s

health limit, and sampling time of seven days, it was unlikely that the amount of TCE

captured in the sorbent tube would be sufficiently high for analysis with the NIOSH 1022

methodology.

When samples are collected it will be important to follow DEC procedures to assure

that the air samples are not compromised by household chemicals. These procedures are:

60

In addition, according to Ken Deshere “advice was passed from neighbor to neighbor as

"folk wisdom" - taking things outside of the house, packing cleaners and solvents into

plastic bins with lids sealed on with duct tape.” Household products commonly

containing TCE include: glues, adhesives, paint removers, spot removers, rug cleaning

fluids, paints, metal cleaners and typewriter correction fluid. Care should be taken to

follow the same procedures as were followed in previous sample collection.

Conclusions

• The equipment at the Civil and Environmental Engineering, Microbiology and

Biological and Environmental Engineering departments of Cornell University is

available for TCE analysis, but a key piece of equipment (a thermal desorber) is

needed to increase existing equipment’s sensitivity.

• Even with the equipment measuring TCE at concentrations below 0.8 μg/m3, low

air concentrations may be difficult to analyze.

• Should a further study investigating air concentrations be undertaken by students

at Cornell University, we suggest:

1. Purchasing or renting a thermal desorber or an electron capture

detector to lower the chromatographic detection limit. In the past,

some companies have been willing to extend an “education”

discount to this kind of community improvement projects or

donate outdated, but still usable equipment. With a thermal

desorber the fish pump sampling method could be used to collect

and analyze samples following the EPA TO-17 methodology.

61

Although new sampling tubes would need to be purchased, the

thermal desorption tubes are reusable.

2. Solicit official analytical laboratories to analyze the student-

collected samples for an educational or no fee.

• Future testing should be pursued to determine changes in ground water levels and

seasonal changes affect TCE vapor intrusion into South Hill basements.

Contacts:

• VWR Scientific Products-(CS2 supplier) <http://www.vwrsp.com> Daniel Frank – Cornell University campus sales representative daniel_frank@vwr.com (800)947-4270 x 4238 (607) 564-0521 (FAX) (800)932-5000 (VWR)

• EMD Chemicals Inc.-(CS2 carrier) <http://www.emdchemicals.com/analytics/EMD_Analytics.asp> (800) 222-0342

• SKC Inc.-Gas and vapor sampling equipment. (Sorbent sample tube supplier) <http://www.skcinc.com/product.asp> Sales department (724) 941-9701

• PETCO-(pump supplier) Account info: Tammo Steenhuis, vlm8@cornell.edu, account pass word 1234vero, sm4y6 (petco discount)

• John Terry-Cornell University Chemical Collector jht1@cornell.edu (607) 255-4389

• Carl Cuipylo DEC Geologist cscuipyl@gw.dec.state.ny.us

• Dr. Eugene Madsen–Laboratory contributor Department of Microbiology B57A Wing Hall Office phone (607) 255-2417 Laboratory phone (607) 255-6030 elm3@cornell.edu

• Dr. Jack Liou-Post-Doc, Gas Chromatography expert Department of Microbiology B75A Wing Hall Office phone (805) 531-3185

62

• Dr. James Gossett–researcher and consultant on remedial action technologies for contaminated land and ground water.

Department of Civil and Environmental Engineering 319 Hollister Hall jmg18@cornell.edu

63

Section 7: Subsurface Transport of TCE M. Ekrem Cakmak

TCE is a colorless solvent with an odor similar to ether. TCE liquid is denser than

water (1.46 g/cm3 > 1.00 g/cm3); this results in the fast downward movement of TCE

through soil until it encounters an impermeable layer. After being confined, TCE will

form Dense Non-Aqueous Phase Liquid (DNAPL) pools. These pools may then dissolve

in water moving past them. The TCE in the water may then sorb onto soil particles, or

degrade under the action of bacteria. This is illustrated for PCE DNAPL by Clement et

al. (2004) in Figure 7-1.

Figure 7-1: Transport processes in subsurface from Clement et al. (2004)

Solubility of TCE in water is 1100 mg/L). This relatively low solubility means that

TCE pools will be dissolved very slowly in the subsurface, and, since there is little TCE

in the water, biodegradation will also be slow (Russell et al., 1992). However, TCE is a

very volatile chemical. It prefers to be in gas phase rather than the liquid phase. Because

of this, the lifespan of TCE in the unsaturated zone can be much less than the lifetime of

64

TCE in the saturated zone (Kueper et al., 2003). TCE will volatilize as it moves

downward through the unsaturated zone above the water table. The TCE-laden air may

vent to the atmosphere or into basements (see the section on Vapor Intrusion). Also

because TCE vapor is 4.5 times denser than air, it can drain gravitationally down slopes

in the water table or other barriers impermeable to it in the subsurface.

Figure 7-2: Mean annual earth temperatures at individual stations,

superimposed on well-water temperature contours. (http://www.geo4va.vt.edu/A1/A1.htm)

TCE can be adsorbed by soil to some extent. However its retardation due to

adsorption is negligible (Russell et al., 1992). The retardation factor for TCE is two,

meaning that it will move half as fast as the water in which it is dissolved.

Biodegradation of TCE depends on many factors such as geology, hydrology,

solubility, climate, and microbial flora of the area. There are two kinds of biological

degradation that can occur for TCE. The first is aerobic, performed by aerobic

microorganisms, which occurs in the presence of oxygen; the second is anaerobic, which

65

occurs in the absence of oxygen. Aerobic microorganisms need oxygen in order to

degrade substances through oxidation. Since TCE is at a highly oxidized state, it does not

submit easily to degradation by aerobic microorganisms. However, there is way to

degrade TCE aerobically under certain conditions (Olniran et al., 2004). Anaerobic

microorganisms can only work without the presence of oxygen and generally need

moderate temperatures.

In the Ithaca region, groundwater temperature varies from 42 to 57º F (Figure 7-2)

and the water table on South Hill can be quite deep (Figure 5.3). Conditions on South

Hill are thus not favorable for biodegradation of TCE. However study of new methods of

bioremediation might be warranted

66

Section 8: Mechanisms of TCE Transport at South Hill Adrian Harpold

Deep Percolation of TCE into the Bedrock

It is the opinion of this study that deep percolation of TCE into the subsurface at

South Hill is likely to have occurred TCE liquid is heavier than water and will displace

water and move vertically downward until it is impeded by a low permeability layer or

dissolves and/or degrades (Figure 8-1). In fractured bedrock, TCE will occupy fractures

smaller than water (because it is denser) and accumulate. Typical fractured rock can

store between 200 mL and 2 L of TCE per cubic meter of bedrock (about 0.1% by

volume) (Keuper et al., 2003). If sizeable pools of TCE accumulate or if groundwater

access to TCE accumulations is minimal, the TCE accumulations may remain in the

subsurface for a very long time (order of hundreds of years).

67

Figure 8-1: One possible scenario for TCE transport in a fractured bedrock (UK Environmental Agency, 2006). This scenario seems plausible for South Hill because fractures are present there and TCE contamination has persisted long after any possible spill. TCE stored in fractured or jointed rock is very difficult to remediate. Figure is from Keuper et al. (2003).

Unfortunately, the geology at South

Hill is conducive to TCE transport in the

bedrock. The bedrock is highly fractured

perpendicular to the surface and bedding

planes occur parallel to the surface. The fire

reservoir may have introduced TCE directly

into the fractured bedrock. Well

measurements near the fire reservoir on the

Emerson site show the highest concentrations

of TCE in the shallow fractured bedrock; Figure 8-2: Process of transport and back-diffusion in a simplified fracture channel. . Figure is from Keuper et al. (2003).

68

however, TCE is present in the glacial till as well as the deep bedrock. Concentrations

have decreased over time (1987-2003) in most monitor wells. This indicates that the

TCE is either moving down-gradient in fractured bedrock, or degrading, or being

removed by remediation efforts.

“Back Diffusion” of TCE in the Bedrock

If TCE is transported in fractured bedrock it will diffuse into the surrounding rock

(Figure 8-2). This is important because ‘back diffusion’ occurs after TCE is flushed from

the fracture. Even if TCE is present in a fracture for only a short time, back diffusion can

continue for many decades. This means that even if TCE is removed from some fractures

by remediation efforts, back diffusion may cause TCE contamination to persist for a long

period of time.

Contaminated Water Reaching the Surface

A likely transport mechanism for TCE at South Hill is water containing dissolved

TCE coming into contact with the pore space air, which then moves into basements.

Concentration of TCE in air in contact with contaminated water can be very high

(60,000,000 ppbv, see Section 2) compared to the levels of TCE tolerable in a basement

(1 ppbv). Only a little air entering a basement from the airspace provided by the tile

drains (see Figure 8-4) can therefore be a problem. As commented earlier, movements in

the ground water table can propel pore space air.

Many basements on South Hill are damp at least at times. Only a very small

amount of contaminated water can produce significant levels of TCE in the basement air.

Figure 8-3 shows how much water is required to raise TCE levels in a 40 X 40 X 10 ft

69

basement to 5 ppbv, assuming that the TCE in the water degasses totally into the

basement air once the water enters the basement. If TCE is saturated in water (1100

mg/L), approximately 10 cm3 of water is required to raise the basement TCE levels to 5

ppbv. This volume is about the size of a grape. Well measurements on South Hill

indicate that groundwater concentrations of TCE are less than 300 mg/L and are usually

on the order of 10 μg/L. At 300 mg/L about 5 grape volumes would be required, and at

10 μg/L a very large amount of water would be required (more than 250 gallons).

Volume vs. Concentration necessary to Exceed 5 ppb TCE in the air

0

50

100

150

200

250

300

350

400

450

0 200 400 600 800 1000

Conc. (mg/L)

Vw (c

m^3

)

Figure 8-3: Graph of Concentration of TCE in water versus the volume necessary to achieve 5 ppb TCE in the air of a 40 X 40 X 10 ft basement. Even at low concentrations only a very small amount of water will cause dangerous air quality.

70

Figure 8-4: Schematic of a house where tile drains are used to drain a high water table. This common situation is problematic because the basement walls may come into direct contact with TCE-contaminated air or water. Figure is from McAlary (2002).

Another means of water and TCE reaching the surface is through seeps. Despite

reports of TCE-type smells at the surface, TCE was not found in the seeps nearby the site.

However, it may be necessary to sample during and after storms, which could cause

different flowpaths to become active. Despite this, it is the opinion of the authors that the

fractures are probably highly flushed and not a major transport pathway at normal flows.

Degradation of TCE in Soil

Degradation of TCE in soil and groundwater is poorly understood. As explained

in the previous section, TCE degrades best under anaerobic conditions. We speculate

that TCE degradation is relatively small because of the low temperatures in the ground

water (reactions are slower at lower temperatures). Previous consultant conclusions were

that TCE may have been present long enough to completely or mostly degrade are

questionable in our opinion because: Measurements over long-periods of time are only

71

available for wells near the fire reservoir. These measurements show decreasing TCE

levels, but do not account for loss of TCE from the remediation system. Additionally, the

byproducts of TCE breakdown do not seem to be sufficient to explain all of the reduction

in TCE. Finally, byproducts do not verify degradation because the original industrial-

grade TCE that was spilled likely contained byproducts.

Diffusion of TCE in Soil and Air

Diffusion is the random movement of molecules and a possible cause of TCE

vapor movement to the surface. A rising water table could introduce TCE-contaminated

water to rock or till at shallower depths. As the water table falls the TCE-rich water is

left clinging to minerals and the TCE will volatilize into air filling the pores. It can then

diffuse through or move with the air. A soil-gas survey performed on South Hill in 2005

found TCE (among five other VOCs) at concentrations from 39.3 to 536 μg/m3 (7.3 to

100 ppbv) (ESC, 2005). This suggests this mechanism may be important at South Hill.

The rate of diffusion depends on the concentration of TCE in the groundwater, how close

the groundwater comes to the surface, and temperature. Results found by other

researchers indicate that diffusion can be a dominant mechanism for TCE loss (Env. Sci.

Tech.). On the other hand, a study by the Department of Energy found that passive

diffusion only contributed 5% of the total TCE transfer to the air (DOE). An illustrative

calculation is given in Appendix C.

72

Groundwater encounters soil contamination and adds to advective transport

Capillarity hold some groundwater with VOCs above the water table which

increases diffusion

Figure 8-5: The rising water table can move TCE into the soil pores near the surface. The closer vapor is to the surface, the more diffusion will contribute to TCE in indoor air. Figure is from McAlary (2002).

Vapor Intrusion of Contaminated Soil Air

Vapor intrusion is the process by which TCE-contaminated air in the soil pores

moves up to the surface and into buildings. Some factors that contribute to the vapor

intrusion problem at South Hill are as follows: steep topography, shallow soils, and

fluctuating water tables. No differentiation is typically made between diffusion (random

movement of TCE molecules) and other vapor intrusion mechanisms. However, it should

be noted that diffusion is a constant slow process, whereas other vapor intrusion

mechanisms, which are driven by movements of the water table or changes in barometric

pressure, can be episodic, and at times can transport TCE much more rapidly than

diffusion alone.

Gas-phase TCE is 4.5 times heavier than air and therefore can move down steep

gradients in the water table through the overlying strata (Figure 8-8). TCE could reach

73

the surface if the hillside intersects the strata through which the TCE-saturated air is

draining. Disturbances to the subsurface, such as pipes, can allow gas-phase TCE to

move preferentially (Figure 8-7).

The ‘Stack Effect’ is a recognized mechanism that brings TCE into residences in

the winter (Figure 8-6). When the home is being heated (or is warmer than the outside)

the pressure difference will move air out of the top of the house and draw air from the

basement. This may be part of the rationale for testing air quality in the winter.

However, testing at additional times in the year would help determine if the Stack Effect

is an important TCE transport mechanism at South Hill.

74

Figure 8-7: Vapor intrusion along a below-ground sewer pipe. The TCE vapor displaced by water or diffused along subsurface. Figure is from McAlary (2002).

Figure 8-6: Diagram of ‘Stack Effect’. Warm air in the house rises out of the top and air is moved into the house from other sources (including soil air). Figure is from McAlary (2002).

Movement of vapor TCE along water table

Figure 8-8. Possible scenario for TCE movement in shallow soil. TCE-laden air in the soil layer above a perched water table could drain down along the top of the water table and drain out near where the perched water table is intersected by the surface (at second house, for example). Figure is from McAlary (2002).

75

Section 9. Operational Suggestions

Entire group including Cathles, Steenhuis, (and Gillett?)

An executive summary of this document is provided at the beginning. Here we

give our perspectives on issues confronting the community.

1. The most important concern is human health, and the most immediate need is to

assure that all of the households that could be affected by TCE contamination are

either tested or appropriately mitigated such that testing is forgone. Figure 3-1

shows that only about ¼ of the potentially affected houses have been tested.

Means should be found to quickly test the houses in this area that have not yet

been tested, in order for these residents to assess the extensive use of basement

facilities or consider mitigation. As an alternative, the presumption would be that

houses would be appropriately mitigated.

2. The concern is with low levels of volatile organic chemicals (VOCs) in indoor air.

Low levels of TCE in drinking water appear (Section II) to be the more serious

health risk, but this is not a factor in South Hill. All residents are served by city

water, which has no TCE contamination.

3. So far 31 of the 89 basements tested (35%) show measurable levels of TCE. The

TCE concentration of all but 3 of the basement samples are below the current

indoor health threshold of 5 μg/m3 (1 ppbv). This does not necessarily mean it is

safe to work for prolonged periods (decades) in these basements, or that the low

level exposure is not hazardous to the young, old, or particularly susceptible. We

do not know the health effects of very long exposure to low levels of TCE.

However, the TCE contamination is low enough that, with mitigation, exposure

76

levels will approach those that would normally be encountered in the human

environment. TCE is a very widely used chemical.

4. The repeatability of the indoor air TCE measurements to date is good. The

standard error of repeat sampling appears to be about 1 μg/m3 (0.2 ppbv).

However, the short-duration of sampling to date cannot preclude that higher levels

of contamination might have episodically occurred.

5. The cost of collecting and analyzing indoor air samples to determine if a house

has TCE in basement air is similar to the cost of mitigating many houses by

installing pumps to sparge the subslab airspace. Because of this, it may make

sense to reduce repeat testing prior to mitigation and offer mitigation to any

homeowner in the potentially affected area that requests it, regardless of the level

of TCE in the tested air. Houses that require extensive repairs or changes (such as

pouring a concrete floor) to seal the basement will be more expensive to mitigate.

Follow up testing to assess the efficacy of mitigation might still be needed.

6. So far about 35% of the homes tested have detectable TCE in basement air, and so

far the sales price of houses on South Hill have risen at the same rate as houses in

Ithaca in general. Since a major concern of homeowners is a decline in house

value, it might make sense to guarantee the house values on South Hill continue

to track the Ithaca average. Under this suggestion, if all offers on a South Hill

house fell below the Ithaca-wide market value for a comparable house, the

homeowner would be reimbursed for the difference between the projected market

value and the top offer received upon acceptance of that offer.

77

If these steps were taken, it appears to us that the adverse consequences to

homeowners of the TCE contamination could be largely contained. The cost of these

steps would not seem to be unduly large, so they may be worth considering. At the same

time, steps could continue to remediate the South Hill area. Because of the fractured

nature of the bedrock and the likely very wide dispersal of the TCE DNAPL, we are not

optimistic that economically feasible or visually acceptable remediation will have much

impact on subsurface TCE contamination, but any reasonable remediation steps should be

considered.

The greatest need as we see it is to define the extent of contamination and

determine the variability of TCE in South Hill basements. The application of methods of

long term monitoring may be particularly valuable. Inexpensive sample collection and

analysis might be provided by Cornell as a community outreach service. This may be the

best way for Cornell to continue to help the South Hill and broader Ithaca community.

78

Appendix A. Glossary of Terms

Activated charcoal: Treated charcoal with increased ability to have chemicals adhere to

it. Adsorption: The gathering of a gas, liquid, or dissolved substance on the surface or

interface zone of another substance Advection: Transportation of contaminants by the flow of a current of water or air Aerobic degradation: Degradation in the presence of air Anaerobic degradation: Degradation in the absence of air Aquifer: An underground geological formation, or group of formations, containing

water; sources of groundwater for wells and springs. Bedrock: solid rock that lies beneath the soil layers Biodegradation: Decomposition (or degradation) of a compound in sequential steps

mediated by biological activity. Carrier gas: The gas that carries the sample in gas chromatography. Chromatographic program/operating parameters: A temperature program that burns

off the compounds in a sample under specified parameters so that each individual substance can travel through the gas chromatograph at known time and temperature.

Conjugation: Alteration of a compound during metabolism by binding to a substance

(typically glucose or glutathion) with a carboxylic acid group. This makes the chemical biologically inactive (generally), water-soluble, and prepares it for urinary excretion in the body.

Degradation: Chemical or biological breakdown of a complex compound into simpler

compounds Dehalogenation: Removal of a bonded halogen (in the case of TCE the chlorines are

halogens) from a chemical. Dense Non-Aqueous Phase Liquid (DNAPL): A liquid that is not water-based (and

does not easily dissolve or mix with water (i.e. immiscible)) and is denser than water. It therefore sinks to the bottom of a well or body of water.

79

Detector: Device that senses and receives a signal (associated with particular and individual chemicals) that is used to process information.

Dispersion: the spatial property of being scattered about over an area or volume Dissolution: Process where a substance is dissolved into a liquid. Electron capture detector (ECD): A type of detector that measures loss of electrons as

individual substances pass through the Gas Chromatograph. Flame ionizing detector (FID): A type of detector that measures changes of current as

individual substances pass through the Gas Chromatograph. Gas chromatograph (GC): A method of separating and measuring individual substances

in a mixture. Genotoxicity: Adverse health effect from a compound that causes a genetic mutation,

which can lead to the development of tumors. Glacial till: the type of topsoil found on South Hill. It is made up of clay, sand, and

gravel-sized pieces of soil and rock mixed together. Headspace: The volume left at the top of a filled bottle before sealing. Heptatoxicity: Adverse health effect from a substance that alters the normal function of

the liver. Hydraulic Head: The elevation of water in an open well. Hydrolysis: Degradation of a chemical compound by breaking bonds that split up the

parent compound using water (H20). One of the parts get an OH and the other gets an H from water.

Impermeable Layer: A layer of material (e.g. clay) in an aquifer through which water

does not pass Joints: Natural fractures in rock that cause it to break into regular, evenly spaced blocks Koc: Organic carbon partitioning coefficient. Gives an estimate of how readily a

compound will be in the organic matter in soils. Larger numbers correspond to higher organic matter partitioning.

Mass spectrometry (MS): An instrument used to identify chemicals in a substance by

their mass and charge.

80

Matrix (rock): Enclosing rock or soil. For example, the open spaces between soil and rocks are called pores. The pores are in the rock/soil matrix.

Mineralize: Degradation of an organic substance into an inorganic phase. Generally

refers to the complete degradation of a compound into CO2 and water. In the case of TCE, mineralization would result in chloride ions, CO2 and water.

Multisorbent concentrator: Equipment used in conjunction with gas chromatography to

concentrate the sample before it is analyzed. Nephrotoxicity: Adverse health effect from a substance that alters the normal function of

the kidneys. Neurotoxicity: Adverse health effect from a substance that alters the normal function of

the nervous system. Oxidation: Oxidation is the addition of oxygen, removal of hydrogen, or the removal of

electrons from an element or compound. In the environment, organic matter is oxidized to more stable substances.

Permeability: The degree to which groundwater can move freely through an aquifer Photolysis: Degradation of a chemical compound by breaking bonds with light energy. Reductive Dehalogenation: Chemical reaction where a halogen (in the case of TCE this

would refer to the chlorides) is replaced with a hydrogen. Saturated zone: The area below the water table where all open spaces are filled with

water under pressure equal to or greater than that of the atmosphere. Siltstone: A fine-grained sedimentary rock similar to shale, but slightly coarser grained.

Water does not flow easily through unfractured siltstone. Solvent: A liquid (carbon disulfide in this case) that can dissolve a substance. Sorbent: A material (activated charcoal in this case) that has the capacity of adsorbing

another substance (TCE). Sorption: Can refer to either absorption or adsorption. Absorption is the incorporation of

a substance from one state into another (i.e. substance A goes into substance B). Adsorption is the physical binding of a substance onto the surface of another molecule (i.e. substance A is on the surface of substance B).

Thermal desorber: A laboratory instrument used as a type of oven to accelerate

volatilization of compounds from sampling media (the media in this case is activated charcoal).

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Unsaturated zone: The area above the water table where soil pores are not fully

saturated, although some water may be present. Volatile organic compound (VOC): Organic substances, which easily become vaporous

or gaseous. Volatility: The ability of a material to evaporate.

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Appendix B. GIS Maps

Figure B1: The spacial location and extent of the area potentially affected by contamination. Property parcels, city roads, streams, and waterways digital data are from the Thompkins County ITS/GIS website: ithacamaps.org. Elevation digital data from the United States Geological Survey website: www.usgs.gov

83

Figure B2: Map of the orientation of joint sets measured by Carl Carl Cuipylo of the New York State Department of Environmental Conservation, and provided for this report via personal communication. The black lines which form right angles show the directions of the fracture planes from several fractures measured on South Hill. Note that most of the fractures point nearly north/south and east/west, and that there are many more fractures on South Hill than are depicted here. Property parcels, city roads, streams, and waterways digital data are from the Thompkins County ITS/GIS website: ithacamaps.org.

84

Figure B3: Location of soil vapor and groundwater monitoring sites, digitized from DOH maps provided as handouts at the February 2006 public meeting. Property parcels, city roads, streams, and waterways digital data are from the Thompkins County ITS/GIS website: ithacamaps.org.

85

Figure B4: The utility lines buried underground in the area of interest. Data digitized from ithacamaps.org and from Figure 4 of "Onsite Assessment of Former BorgWarner-Morse Chain Facility 620 N Aurora St. Ithaca, NY", a report prepared by Environmental Strategies Consulting, received at the Thompkins Couty Public Library on December 13, 2005. Property parcels, city roads, streams, and waterways digital data are from the Thompkins County ITS/GIS website: ithacamaps.org.

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Appendix C: Relative Magnitudes of Diffusion and Vapor Intrusion Adrian Harpold

Goal: Find the relative importance of diffusion of TCE through the soil versus vapor

intrusion caused by water table movement.

Estimating Diffusive Flux:

Using Fick’s law the diffusion flux can be estimated for several different scenarios:

dXdCDJ ed −= , where Jd is the diffusion flux, De is the adjusted diffusion coefficient, C is

concentration and X is distance. Diffusion (D) of TCE in air can be estimated to be 0.1

cm2/s or 8500 cm2/day. Equivalent diffusion (De), accounting for diffusion through soil

pores, can be estimated using 2

3/10

φφa

e DD = , where фa is the air filled porosity (0.2) and

ф is the total porosity (0.4). As a result De equals 2500 cm2/day.

Distance to water table (m)

Dissolved Concentration

(mg/L)

Difference in Vapor Concentration

(ug/m^3) between surface and groundwater

Diffusion flux (ug/m^2/day)

1 0.0001 26.3 6.575 1 0.004 1052 263 5 0.0001 26.3 1.315 5 0.004 1052 52.6

10 0.0001 26.3 0.6575 10 0.004 1052 26.3

Estimating Flux of TCE from Rising Water Table:

Flux of vapor TCE caused by a rising water table can be estimated using

φ∗∗Δ= CGJ W , where J is the vapor intrusion flux, ΔGW is the height the ground water

87

rises, and ф is the porosity of the soil. This method assumes that the air in the pores

above the water table contains vapor TCE. The flux of TCE from vapor intrusion is

estimated for various changes in water table height and TCE concentrations.

Change in GW table (m/day)

Vapor Concentration

(ug/m^3)

Vapor flux (mg/m^2/day)

0.5 26.3 2.630.5 1052 105.2

1 26.3 5.261 1052 210.42 26.3 10.522 1052 420.8

Conclusion:

Vapor TCE fluxes are similar for diffusion and vapor intrusion for the scenarios given.

However, the scenario for vapor intrusion is valid when the groundwater table is rising,

which only occurs during small portions of the year. Diffusion of TCE occurs at all times

and therefore is a more critical TCE transport pathway.

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Appendix D: References

Agency for Toxic Substances and Disease Registry (ATSDR). 1997. Toxicological profile for trichloroethylene (TCE). Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service.

Axelson O., K. Anderson et al. 1994. “Updated and expanded Swedish cohort study on trichloroethylene and cancer risk.” Journal of Occupational Medicine, 36, 556- 562.

Barton, H. A and H. J. Clewell III. 2000. “Evaluating Non-cancer effects of Trichloroethylene: dosimetry, mode of action and risk assessment.” Environmental Health Perspectives, 108 (suppl 2), 323-334. Barton, H. A. and S. Das. 1996. “Alternatives for a risk assessment on chronic non-

cancer effects from oral exposure to trichloroethylene.” Barton, H. A., C. D. Flemming and J. C. Lipscomb. 1996. “Evaluating human variability

in chemical risk assessment: hazard identification and dose-response assessment for non-cancer oral toxicity to trichloroethylene.” Toxicology, 111, 271-287.

Bove FJ, Fulcomer MC, Klotz JB, et al. 1995. “Public drinking water contamination and

birth outcomes.” Am J Epidemiol 141:850-862. Buorg, A. C. M., Mouvet C, Lemer DN. 1992. “A review of the attenuation of

trichloroethylene in soils and aquifers.” Q Journal of Engineering Geology, 25, 359-370.

Byers VS, Levin AS, Ozonoff DM, et al. 1988. “Association between clinical symptoms

and lymphocyte abnormalities in a population with chronic domestic exposure to industrial solvent-contaminated domestic water supply and a high incidence of leukemia.” Cancer Immunol Immunother 27:77-8 1.

Clement, T.B., Gautam, T.R., Lee, K.K., Truex, M.J., Davis, G.B., 2004. “Modeling of

DNAPL-Dissolution, Rate-Limited Sorption and Biodegradation Reactions in Groundwater Systems,” Bioremediation Journal, 8(1-2):47-64.

Daley, Jennie. 2005. Nice home- tough sell. Ithaca Journal. Accesses online:

http://www.theithacajournal.com/apps/pbcs.dll/article?AID=/20050824/NEWS01/508240324/1002

Dilling WL, Tefertiller NB , Kallos GJ. 1975. “Evaporation rates and reactivities of

methylene chloride, chloroform, 1 , 1, 1-trichloroethane, trichloroethylene, tetrachloroethylene, and other chlorinated compounds in dilute aqueous solutions.“ Environmental Science and Technology, 9, 833-838.

89

Dobrev, Ivan D., Melvin E. Andersen and Raymond S. H. Yang. 2001. “Assessing

interactions thresholds for trichloroethylene in combination with trichloroethylene in combination with tetrachloroethylene and 1,1,1-trichloroethane using gas uptake studies and PBPK modeling.” Archeological Toxicology, 75, 134-144.

Dobrev, Ivan D., Melvin E. Andersen and Raymond S. H. Yang. 2002. “In silico

toxicology: simulating interaction thresholds for human exposure to mixtures of trichloroethylene, tetrachloroethylene and 1,1,1-trichlorothane.” Environmental Health Perspectives. 110 (10), 1031-1039.

“Earth Temperature and Site Geology.” Virginia Tech, http://www.geo4va.vt.edu/A1/A1.htm. Ertle, T., D. Henschler, G. Muller and M. Spassowski. 1972. “Metabolism of

trichloroethylene in man I. The significance of trichloroethanol in long-term exposure conditions.” Archeological Toxicology, 29, 171-188.

ESC. 18 September 2005. Groundwater evaluation and remediation area Emerson Power

and Transmission Facility. Ithaca, NY. ESC. 31 October 2005. Geophysical Survey Investigation Emerson Power and

Transmission Facility. Ithaca, NY. Fisher, Jeffery W., Deirdre Mahle and Richat Abbas. 1998. “A human physiologically

based pharmacokinetic model for trichloroethylene and its metabolites, trichloroacetic acid and free trichloroethanol.” Toxicology and Applied Pharmacology, 152, 339-359.

Garbarini, DR, Lion LW. 1986. “Influence of the nature of soil organics on the sorption

of toluene and trichloroethylene.” Environmental Science and Technology, 20, 1263-1269.

Iavicoli, Ivo, Alasandro Marinaccio, Giovanni Carelli. 2005. Effects of occupational

trichloroethylene on cytokine levels in workers. J. of Occupational and Environmental Medicine, 47(5), 453-457.

Kilbum KH, Warshaw RH. 1992. “Prevalence of symptoms of systemic lupus

erythematosus (SLE) and of fluorescent antinuclear antibodies associated with chronic exposure to trichloroethylene and other chemicals in well water.” Environ Res 57: l-9.

Kilbum KH, Warshaw RH. 1993. “Effects on neurobehavioral performance of chronic

exposure to chemically contaminated well water.” Toxicol Ind Health 9:391-404.

90

Kueper, B.H., Wealthall, G.P., Smith, J.W.N., Leharne, S.A., Lerner, D.N., 2003. An Illustrated Handbook Of DNAPL Transport and Fate In The Subsurface, Published by Environmental Agency of U.K., Bristol.

Lash, Lawrence H., Jeffrey W. Fisher, John C. Lipscomb and Jean C. Parker. 2000.

“Metabolism of Trichloroethylene.” Environmental Health Perspectives, 108 (suppl 2), 177-200.

Moore, Martha M. and Karen Harrington-Brock. 2000. “Mutagenicity of

trichloroethylene and its metabolites: implications for the risk assessment of trichloroethylene.” Environmental Health Perspectives, 108 (suppl 2), 215-223.

National Environmental Methods Index (1992) NEMI Method Summary Method 524.2:

Measurement of Purgeable Organic Compounds in Water by Capillary Column Gas Chromatography/Mass Spectrometry. May 15, 2006. <http://web1.er.usgs.gov/nemi/method_summary.jsp?param_method_id=4803> <http://www.ultrasci.com/Docs/500/524_2.PDF>.

National Institute of Occupation Safety and Health. (1994). Manual of Analytical

Methods 4th ed: Trichloroethylene Method 1022, Issue 2. April 16, 2006. <http://www.cdc.gov/niosh/nmam/pdfs/1022.pdf>.

Nomiyama K, Nomiyama H. 1977. “Dose-response relationship for trichloroethylene in

man.” International Arch Occupational and Environmental Health, 39, 237-248.

Olaniran, A.O., Pillay, D., Pillay, B. 2004. “Chloroethenes contaminants in the environment: Still a cause for concern.” African Journal of Biotechnology, 3(12), 675-682.

Pearson CR, McConnell G. 1975. “Chlorinated Cl and C2 hydrocarbons in the marine

environment.” Proc R Sot Lond [Biol],189, 305-332. Radian Corporation. 13 July 1987. Preliminary Environmental Assessment of Fire Water

Reservoir.

Russell, H.H., Matthews, J.E. and Sewell, G.W., 1992. “TCE Removal from Contaminated Soil and Ground Water,” EPA Ground Water Issue, EPA/540/S- 92/002.

Saisho K, Hasegawa Y, Saeki M, et al. 1994. “Bioaccumulation of volatile chlorinated hydrocarbons in blue mussel, Mytilus edulis, and killifish, Oryzias Zutipes.” Eisei Kagaku 40:274-278. (Japanese)

Schroll R, Bierling B, Cao G, et al. 1994. „Uptake pathways of organic chemicals from

soil by agricultural plants.” Chemosphere 28:297-303.

91

Seiji K, Jin C, Watanabe T, et al. 1990. “Sister chromatid exchanges in peripheral lymphocytes of workers exposed to benzene, trichloroethylene, or tetrachloroethylene, with references to smoking habits.” International Arch Occupational and Environmental Health, 62,171-176.

Toevs, I. and Gleitsmann, B., 2005. Report on South Hill Geology. Soil&Water

Laboratory, Cornell University, Ithaca, NY. U.S. Environmental Protection Agency. (1999). Compendium Method TO-15:

Determination of Volatile Organic Compounds (VOCs) in Air Collected in Specially-Prepared Canisters and Analyzed by Gas Chromotography/Mass Spectrometry (GC/MS) 2nd ed. April, 16, 2006. <http://www.epa.gov/ttn/amtic/files/ambient/airtox/to-15r.pdf>.

U.S. Environmental Protection Agency. (1999). Compendium Method TO-17:

Determination of Volatile Organic Compounds in Ambient Air Using Active Sampling onto Sorbent Tubes 2nd ed. April, 16, 2006. <http://www.epa.gov/ttn/amtic/files/ambient/airtox/to-17r.pdf>.

US EPA 2005. “List of drinking water contaminants and MCLs: drinking water

contaminant fact sheet for trichloroethylene.” Washington, DC: US Environmental Protection Agency.

Wallace, L. A., E. D. Pellizzari, T. C. Hartwell. 1985. “Personal exposures, indoor-

outdoor relationships and breath levels of toxic air pollutants measured for 355 persons in New Jersey.” Atmospheric Environment, 19, 1651-1661.

Watenberg, Daniel, David Reyner and Cheryl Siegel Scott. 2000. “Trichloroethylene and

cancer: epidemiological evidence.” Environmental Health Perspectives, 108 (suppl 2), 161-176.

Wu, Chieh and John Schaum. 2000. “Exposure Assessment of Trichloroethylene.”

Environmental Health Perspectives, 108 (suppl 2), 359-363.