United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R04-89/056
September 1989
Superfund
Record of Decision
Ciba-Geigy (Mclntosh Plant), AL
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50272-101
REPORT DOCUMENTATION
PAGE
1. REPORT HO.
EPA/ROD/R04-89/056
X Recipient • Acceeaion No.
4. Title and Subtitle
SUPERFUND RECORD OF DECISION.
Ciba-Geigy (Mclritosh Plant), AL
First Remedial Action
5. Report Date
09/28/89
7. Autfior(i)
8. Performing Organization Rept No.
9. Performing Organization Name and Addm««
10. Pro|ecVTa*fc/Work Unit No.
11. Contnct(C) or Grant(G) No.
(C)
(G)
12. Sponsoring Organization Name and Addreaa
U.S v -Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. Type of Report ft Period Covered
800/000
14.
15. Supplementary Note*
16. Abatract (Limit: 200 word*)
The 1,500-acre Ciba-Geigy (Mclntosh Plant) site is in southern Washington County;
northeast of Mclntosh, Alabama. The plant's initial operations, which began in 1952,
were devoted solely to the manufacture of DDT. In 1970, the facility expanded its
manufacturing operations to include herbicides, insecticides, and chelating and
sequestering agents. Other products produced by Ciba-Geigy include resins and additives
used in the plastics industry. Wastes and residues generated during production
operations were managed onsite. In 1.985, EPA issued Ciba-Geigy a RCRA Part B permit for
active waste management units onsite. The permit included a corrective action plan
requiring Ciba-Geigy to remove and treat contaminated ground water and surface water at
the site. In 1987, as part of this plan, Ciba-Geigy installed a ground water pumping
and treatment system which has been effective in addressing the ground water
contamination. This first of three planned operable units addresses ground water
contamination in the shallow Alluvial aquifer. The second operable unit will address
the deeper Miocene aquifer and the final operable unit will address contamination of
soil at eleven former waste management areas. The primary contaminants of concern
affecting the ground water are VOCs including benzene and toluene; other organics
including pesticides; and metals including arsenic. (Continued on next page)
17. Document Analysis a. Descriptor*
Record of Decision - Ciba-Geigy (Mclntosh Plant), AL
First Remedial Action
Contaminated Medium: gw
Key Contaminants: VOCs (benzene, toluene), other organics (pesticides), metals
(arsenic)
b. Identifiers/Open-ended Term*
c. COSATI Held/Group
18. AvaUabUty Statement
19. Security Clae*(Thl» Report)
None
20. Securtty
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EPA/ROD/R04-89/056 . . ' .
Ciba-Geigy, AL
16. Abstract (Continued) . . .
The selected remedial action for this site includes no further action for the shallow
aquifer beyond continued ground water pumping and onsite treatment using an existing
biological wastewater treatment system, followed by discharge to the Tombigbee River
under an NPDES permit; and ground water and effluent monitoring. The estimated annual
O&M cost for this remedial action is $325,000.
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DECLARATION
of the
RECORD OF DECISION
SITE NAME AND LOCATION
Ciba-Geigy Site
Mclntosh, Washington County, Alabama
STATEMENT OF BASIS AND PURPOSE
This decision document represents the selected remedial action for
the Ciba-Geigy Site, Mclntosh, Alabama, developed in accordance with
the Comprehensive Environmental Response, Compensation and Liability
Act of 1980 (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act of 1986 (SARA) 42 U.S.C. Section 9601 et sea..
and to the extent practicable, the National Contingency Plan (NCP) 40
CFR Part 300.
The following documents form the basis for the selected Remedial
Action:
- Evaluation of the impact of the waste disposal operations on the
Alluvial aquifer with recommendations for Remedial Action at the
Ciba-Geigy Corporation Plant site. Ciba-Geigy Corp., August 27,
1984,
- Ciba-Geigy Corporation, Mclntosh, Alabama - Remedial
Investigation Report, Volumes I and II Appendices A thru 0.
- Draft Hydrogeological Assessment Report, Dynamac Corporation,
April 28, 1989.
- Ciba-Geigy Corporation, Mclntosh Plant Groundwater Review and
Update/ June 1989.
- Groundwater Risk Assessment for the Record of Decision,
July 26, 1989.
The State of Alabama has concurred on the selected remedy.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this site,
if not addressed by implementing the response action selected in this
ROD, may present an imminent and substantial endangerment to public
health, welfare or the environment.
DESCRIPTION OF SELECTED REMEDY
This site will be addressed as three separate operable units. This
Record of Decision (ROD) will only address the first operable unit.
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The first operable unit is "No Further Action" for the shallow
Alluvial aquifer. The Agency concurs with the previous remedial
action taken at the site by Ciba-Geigy as required by the Resource
Conservation and Recovery Act (RCRA) . Future RODs to be issued will
address the second and third operable units. The second operable
unit will address the deeper Miocene aquifer. The third operable
unit will address the contamination source (contaminated soils).
Operation and maintenance activities will be required to ensure the
continued effectiveness of the groundwater treatment system required
by Operable Unit 1.
STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the
environment, attains federal and state requirements that are
applicable or relevant and appropriate, and is cost-effective. This
remedy satisfies the preference for treatment that reduces toxicity,
mobility, or volume as a principal element. Finally, it is
determined that this remedy utilizes a permanent solution and
alternative treatment technology to the maximum extent practicable.
Because this remedy will not result in hazardous substances remaining
on-site above health-based levels, the five year review will not
apply to this action.
EPA will ensure continued protection of human health and the
environment through the RCRA permit process during the implementation
for this operable unit.
SEP 2 8 1989
GREER C. TIDWELL, REGIONAL ADMINISTRATOR DATE
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RECORD OF DECISION
SUMMARY OF REMEDIAL ALTERNATIVE SELECTION
CIBA-GEIGY SITE
MCINTOSH, WASHINGTON COUNTY, ALABAMA
PREPARED BY:
U. S. ENVIRONMENTAL PROTECTION AGENCY
REGION IV
ATLANTA, GEORGIA
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TABLE OF CONTENTS
1,0 Introduction • 1
1.1 Site Location 1
1.2 Site History and Operations 1
1.3 Enforcement Activities 3
2.0 Community Relations *.. ... ..'.. .6
3.0 Scope of Operable Unit within Site Strategy 6
4.0' Site Characteristics 7
4.1 Geology/Soils .......7
. 4.2 Hydrogeology 8
... • 4.3 Surface Water 9
4.4 Former Waste Management Areas. 9
4.5 Summary of Groundwater Sampling Activities For the
Alluvial Aquifer 10
5.0 Site Risks .10
5.1 Summary of Site Risks 10
5.2 Exposure Assessment 15
5.3 Toxicity Assessment .16
5.4 Risk Characterization 16
5.5 Clean Up Goals 18
6 .0 Description of Alternatives 20
6.1 Alternative 1 - No Action 20
6.2 Alternative 2 - No Further Action 20
'7.0 Summary of Comparative Analysis of Alternatives .21
7 .1 Implementability 21
7.2 Cost .21
7.3 State Acceptance 22
7.4 Community Acceptance 22
7.5 Protectiveness of Human Health and the Environment......22
7.6 Compliance With Applicable or Relevant and Appropriate
Requirements 22
7 .7 Reduction of Toxicity, Mobility or Volume 22
7.8 Long-term Effectiveness .22
8 .0 Selected Remedy . . 23
9 .0 Statutory Determination .... 2 3
9.1 Protective of Human Health and the Environment...... — .23
9.2 Attainment of ARARs ....24
9 .3 Cost Effectiveness 24
9.4 Utilization of Permanent Solutions to the Maximum
Extent Practicable 24
9.5 Preference for Treatment as a Principal Element.... 24
10.0 Responsiveness Summary 24
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LIST OF TABLES
Table 4-1 Contaminant Levels In Corrective Action Monitoring
Wells at Ciba-Geigy Site for the Last Three Quarters.... 12
Table 5-1 Hazardous Substances Found in the Groundwater at the
Ciba-Geigy Site ... .14
Table 5-2 Critical Toxicity Values and Risk Characterization for
Groundwater Contaminants at the Ciba-Geigy Site... 17
Table 5-3 Clean Up Goals for Hazardous Substances Found in
Groundwater at Ciba-Geigy Site . 19
-ii-
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LIST OF FIGURES
Figure 1 Clba-Geigy Corporation, Vicinity Map 2
Figure 2 Site Locations 4
Figure 3 Plate 1 - Water/Surface of Alluvial Aquifer
June 16, 1989 11
-iii-
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Record of Decision
Ciba-Geigy Site
Mclntosh, Alabama
1.0 INTRODUCTION
1.1 SITE LOCATION
The Ciba-Geigy Corporation Mclntosh Plant is located in southern
Washington County, northeast of Mclntosh, Alabama, approximately 50
miles north of Mobile, Alabama (Figure 1). The developed plant is
located at 31° 15'00" north latitude and 87° 58'00" west
longitude. The developed plant site, which encompasses approximately
2.4 square miles, is situated between the Southern Railroad
right-of-way on the west and extends nearly to the escarpment
separating the upland terrace from the floodplain of the Tombigbee
River. The property boundaries extend beyond the railroad westward
toward U.S. Highway 43. The northern edge of the property merges
into a pine forest. To the south the property is bounded by Olin
Corporation. The southeastern portion of the property extends to the
banks of the Tombigbee River.
1.2 SITE HISTORY AND OPERATIONS
The Ciba-Geigy Mclntosh facility, formerly owned by Geigy Chemical
Corporation, began operations in October 1952, with the manufacture
of one product, dichlorodiphenyl-trichloroethane (DDT). Through 1970,
Geigy expanded its Mclntosh facilities by adding the production; of
fluorescent brighteners used in laundry products; herbicides;
insecticides; agricultural chelating agents; and sequestering agents
for industry.
In 1970, Geigy merged with Ciba (Chemical Industry in Basel,
Switzerland), forming the Ciba-Geigy Corporation. Since then
Ciba-Geigy has continued to expand its present operations with the
added production of resins and additives used in the plastics
industry, anti-oxidants, and small-volume specialty chemical products
(i.e. water treatment chemicals and fire fighting foams). The
present facility occupies approximately 1,500 acres and employs about
1,200 workers. New facilities for resins and additives production
are planned to be on-line in 1990, increasing the work force by about
140 workers.
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3CX PBOJECT NO. 03-^200-01
CI3A-GEIGY COHPORATION
REMEDIAL INVESTIGATION / FEASIBILITY STUDY
FIGURE
VICINITY MAP
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The EPA Region IV Environmental Services Division (BSD) of Athens,
Georgia conducted an investigation in August 1982 of the Olin
Chemical Company adjacent to the Ciba-Geigy site, and sampled a
drinking water well on Ciba-Geigy property. This sampling revealed
information which warranted further evaluation of the site
contamination problem at Ciba-Geigy. In June 1983, the Hazardous
Ranking System (HRS) survey was completed and a ranking of 53.42 was
given the site. The Ciba-Geigy Mclntosh Plant was included on the
National Priorities List (NPL) in September 1983.
The Ciba-Geigy Mclntosh Plant is currently operating under a RCRA
permit issued in 1985. A condition of Part VII, (Condition VII B),
of the permit was to develop a Work Plan for the performance of a
Remedial Investigation/Feasibility Study (RI/FS). Subsequent to the
approval by EPA of the Work Plan, Ciba-Geigy was to conduct the RI/FS
to develop remedial strategies for the eleven identified
CERCLA-related subsites described in the next section. The RI/FS
program is being conducted in coordination with the RCRA approved
Corrective Action Program which addresses the capture and treatment
of groundwater at the site. In addition to the collection and
treatment of groundwater, the RCRA permit requires the removal of the
existing wastewater collection and conveyance system, surface
impoundments, and landfills. Two impoundments and two landfills have
been closed to date. A total of ten additional units are affected by
this program. The resulting waste materials are being solidified
and/or incinerated and are being placed in a permanent RCRA
above-ground land vault, measuring approximately 400' by 150',
located on-site. Figure 2 depicts the location of CERCLA and RCRA
sites within the Ciba-Geigy Mclntosh plant.
1.3 ENFORCEMENT ACTIVITIES
To date, extensive corrective action activities have been undertaken
at the Mclntosh Plant under RCRA authority. The RCRA Part B permit
addresses the active units of the plant. Superfund authority is
being utilized to investigate eleven former disposal areas and the
resulting groundwater contamination.
In October 1985, EPA issued Ciba-Geigy a RCRA Part B permit, which
included a corrective action plan requiring Ciba-Geigy to remove and
treat contaminated groundwater and surface water at the site. The
corrective action plan stipulated that Ciba-Geigy would prepare a
Remedial Investigation/Feasibility Study (RI/FS).
In accordance with the corrective action plan, Ciba-Geigy retained
BCM, a technical consultant, to perform the RI/FS, which began in
October 1985. The principal finding of the RI study was the
definition of eleven previous waste management areas within the study
area.
The objective of the corrective action plan is source removal and the
prevention of further migration of contaminants detected in the
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groundwater. In accordance with this plan, two surface impoundments
and two landfills at the sites were closed in 1986 and 1987. Final
closure of an additional ten surface impoundments began in 1988 and
is scheduled for completion in December 1989.
In addition to the eleven CERCLA waste management areas, a number of
RCRA-regulated facilities are found at the Mclntosh plant. Ten such
facilities have been closed or are scheduled for closure under the
RCRA Part B permit. The following is a brief description of the
closed units.
- Diazinon Wastewater Sewer: Utilized to pipe Diazinon waste to
the Diazinon Destruct Impoundment. Taken out of service in
1976.
- Triangular Impoundment: Constructed in the 1970s to decompose
Diazinon residues. Closure completed in 1986.
- Rectangular Impoundment: Constructed in 1972-1973 to hold
• sludge from the dilute impoundment. Closure completed in 1987.
- Class C Landfill: Permitted by Alabama in 1973 and permitted
under RCRA Interim Status regulations. Closure completed in
1987. ' - .; . .- -:.-:--.- ••;:.'
- Biological Sludge Landfill: Permitted by Alabama in 1978 and
later operated under RCRA Interim Status for disposal of
dewatered sludge. Closure completed in 1987.
- Diazinon Destruct Impoundment: Constructed in 1965. Closure
in progress.
- GM-44 Impoundment: Put into service in early 1970s.
Constructed for the GM-44 wastes high in nitrogen compounds.
Its use was discontinued in the late 1970s. Closure in
progress.
- Effluent Diffuser Line: Constructed in late 1968 to convey
effluent for discharge into the Tombigbee River. Line was
idled in 1973.
- Effluent Disposal Well: Installed in 1971. Used for the
injection of biotreated effluent to reduce the quantity of NaCl
discharged into the river. The use of the well was
unsuccessful and it was plugged in 1983. ADEM required no
post-closure monitoring.
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- Dilute Ditch: This ditch collected dilute wastewater and
surface water runoff to be conveyed to the Dilute Impoundment.
Use ceased in 1971.
In 1987, Ciba-Geigy installed a groundwater pumping system consisting
of ten fully penetrating, alluvial pumping wells to intercept and
remove contaminated groundwater from the shallow alluvial aquifer.
The water removed from these wells is treated by the plant's on-site
biological wastewater treatment system that was completed in the fall
of 1988. The treated water is discharged into the Tombigbee River in
compliance with appropriate National Pollutant Discharge Elimination
System (NPDES) Regulations. Ciba-Geigy has installed four (4)
corrective action monitoring wells along the southern boundary of the
property to monitor the effectiveness of the pumping well system.
The effectiveness of the pump and treat system in addressing the
groundwater contamination is well established; therefore, EPA is
issuing the Record of Decision after any public comments were
carefully considered. This ROD identifies the EPA selected remedy
for site contamination for operable unit 1. The eleven sites
identified in the RI will be the primary focus of the FS which is
scheduled for completion in November 1989.
2.0 COMMUNITY RELATIONS .
A public meeting was held on September 13, 1989 at 7:30 pm
to present EPA's Proposed Plan for remediation of the shallow
groundwater aquifer to the public. The meeting was conducted at
Mclntosh Town Hall in Mclntosh, Alabama.
The RI was placed in the repository and was available to the public
August 15, 1989. The Proposed Plan and public notice were sent out
August 28, 1989 and September 6, 1989 respectively. A public meeting
was held on September 13, 1989, to present the findings of the RI and
EPA's preferred remedial alternatives. The public comment period
started August 30, 1989 and ended September 27, 1989.
A responsiveness summary has been prepared to summarize community
concerns and to provide a response. A transcript of the public
meeting is available for review in the repository.
3.0 SCOPE OF OPERABLE UNIT WITHIN SITE STRATEGY
As with many Super fund sites the problems at Ciba-Geigy Site are
complex. As a result EPA organized the work into three (3) operable
units (OUs). The operable units at this site are:
O.D. #1 Contamination of the shallow (Alluvial) groundwater
aquifer
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O.U. #2 Contamination of the deep (Miocene) groundwater
aquifer, if contamination is found during additional
sampling.
O.D. #3 Contamination of soils at the eleven (11) former waste
management areas.
Operable Unit #1 which will address the alluvial aquifer is now under
consideration. As part of the Groundwater Corrective Action Program
under Part VIII of Ciba-Geigy's RCRA Permit, a groundwater intercept,
removal and treatment system with surface water discharge was
constructed by the Ciba-Geigy Corporation. This system provides for
recovery and treatment of groundwater at the site. Since the
groundwater from the "CERCLA" site cannot be distinguished from the
RCRA facility groundwater, EPA has evaluated the existing system and
the risks being posed by the groundwater in the alluvial aquifer as
it relates to the "CERCLA" site. Based on this evaluation, EPA will
determine if the present system is achieving the CERCLA clean-up
objective to prevent current or future-exposure to contaminated
groundwater. This operable unit is consistent with plans for future
work to be conducted at the site.
4.0 SITE CHARACTERISTICS
4.1 GEOLOGY/SOILS
The Ciba-Geigy property is located within the Southern Pine Hills,
which are elevated features that regionally slope southward toward
the Gulf of Mexico. These hills are dissected by various river
systems that feed into the Gulf. The plant is located upon a low
terrace adjacent to the floodplain of one of these rivers, the
Tombigbee River. The property lies within the Mobile Graben, a
downthrown fault block paralleling the river.
The surficial and shallow geology can be broken into three distinct
features. The uppermost layer is a relatively continuous clay layer.
containing sand and silty sand lenses and layers that range from only
a few feet to over 50 feet in thickness. Underlying the clay layer
are Pleistocene-age alluvium and low terrace deposits of interbedded
gravel, silt, and clay with thicknesses ranging from 60 to 100 feet.
These deposits outcrop throughout the area.
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Underlying the low terrace deposits are alternating layers of
Miocene-age gravels, sands/ and clays. Regionally, Upper Miocene
clay hydraulically separates the Miocene and Pleistocene deposits.
Erosion and redeposition of these sediments reflect dynamic
depositional environments which are common on a regional scale. This
has resulted in a complex subsurface stratigraphy. Variations of
physical characteristics (e.g. porosity, grain size, hydraulic
conductivity) both vertically and laterally within the strata
complicate the movement of water in the subsurface.
Nine different soil series are located within the area of the plant.
These soils are generally loamy clays and sands that range from well
drained to poorly drained. Permeability ranges from moderate to low.
4.2 HYDROGEOLOGY
Both the Pleistocene and Miocene strata are water bearing and
represent two distinct aquifers, the Alluvial and Upper Miocene.
They are separated by a number of shale and clay aquitards and
aquicludes.
The Alluvial aquifer is composed of the Recent and Pleistocene
terrace and alluvial deposits. The thickness of the aquifer and the
water level depend on the thickness and configuration of the
overlying clay layer. Under natural, semi-confined conditions, the
saturated thickness of the Alluvial aquifer ranges from less than 30
feet to over 50 feet. Recharge of the Alluvial aquifer comes
locally, from rainfall, streams, and reservoirs. Approximately 15 to
25 percent of the annual rainfall contributes to recharge. High
floods also act as recharge mechanisms.
The Alluvial aquifer water level normally slopes gently to the
south-southeast toward the Tombigbee River. However, this pattern is
modified by the pumping and capture of groundwater by the plant,
recharge from the site reservoir, and by the Corrective Action
Program described previously. The EPA and Alabama Department of
Environmental Management (ADEM) approved program was designed to
reduce the level of contaminants in the groundwater below the
facility and has reversed the direction of ground water flow as a
result of the pumping.
The Upper Miocene underlying the plant is a confined aquifer of sands
and gravels capped by a clay layer about 100 to 130 feet in
thickness, according to reports completed by Ciba-Geigy contractor
PELA, Inc. Recharge of this aquifer is believed to come from
regional infiltration in outcrop areas up-dip to the north. In
contrast to the Alluvial aquifer, the quality of Upper Miocene water
can be effected by regional influences such as salt domes or
saltwater intrusion from the Gulf of Mexico.
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It has been reported that the Upper Miocene aquifer and the Alluvial
aquifer are hydraulically connected in some areas. Additionally,
paleo-channeling has been found to exist in the .surface of the
Miocene clay. During the investigation for the Groundwater Corrective
Action Program, and as a part of the RI/FS oversight contract, it was
determined that the two aquifers are not hydraulically connected.
4.3 SURFACE WATER
The Ciba-Geigy property lies within the Tombigbee River Basin which
has a drainage area of 8,378 square miles. The Tombigbee River flows
past the site, converging further south with the Alabama River to
form the Mobile River.
Surface water features at the Ciba-Geigy plant include the diverted
Johnson Creek on the northern edge of the property, and a large,
man-made reservoir between the manufacturing area and the waste
management facilities. Surface water runoff on the northern,
undeveloped corner of the developed portion of the property drains
off-site into the Tombigbee River. The surface water system on the
southern portion of the site below Johnson Creek is undergoing
extensive change. In addition to a new wastewater treatment system,
a new stormwater management system has been constructed to replace
the old combined dilute wastewater/stormwater system, which used
stormwater sewers, open surface ditches, and the dilute ditch to
convey mixed dilute wastewater and stormwater to the dilute
impoundment. The new system segregates all wastewater, dilute and
process, to the wastewater collection and transfer system and then on
to the treatment system. All stormwater sewers have been renovated
and all open ditches have been replaced with stormwater sewers
draining to stormwater retention tanks capable of holding a one-inch
rainfall over the entire developed manufacturing area of the plant.
All initial rainwater retained is transferred to the biological
wastewater treatment plant. All stormwater overflow (rainfall above
one inch) is diverted to established drainageways discharging to the
Tombigbee River.
4.4 FORMER WASTE MANAGEMENT AREAS
The Ciba-Geigy MeIntosh plant has been in operation since 1952.
Since that time, portions of the facility have been used for
management of waste and residues generated by production operations.
A total of eleven CERCLA sub-sites have been identified and will be
the subject of a subsequent ROD on the contaminated soils. The
subsites to be addressed are:
1. - Original Effluent Impoundment
2. - Waste Burial Area
3. - Tar Disposal Area
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4. - Waste Disposal Pits
5. - Open Burn Area
6. - Temporary Trash Staging Area
7. - Disposal Site South of Class "C" Landfill
8. - Bluff Line Area
9. - BHC Burial Area
10. - Warehouse 218
11. - Trash Staging Area
4.5. SUMMARY OF GROUNDWATER SAMPLING ACTIVITIES FOR THE ALLUVIAL
AQUIFER
As a result of EPA's investigatory findings at the Ciba-Geigy site,
the company hired P.E. LaMoreaux and Associates, Inc., (PELA) to
install groundwater monitoring wells at the site and to perform a
hydrological investigation. Based on the presence of a large variety
of chemicals, mainly from the manufacture of insecticides,
pesticides, herbicides and various industrial and agricultural
chemicals, (Shown in Table 5-1) in the soil and groundwater, EPA
issued Ciba-Geigy a RCRA Part B permit, which included a corrective
action plan requiring Ciba-Geigy to remove and treat contaminated
groundwater and surface water at the site.
In 1987, Ciba-Geigy installed a groundwater pumping system consisting
of ten (10) fully penetrating, alluvial pumping wells to intercept
and remove contaminated groundwater from the shallow alluvial
aquifer. Ciba-Geigy has installed four (4) corrective action wells
along the southern boundary of the property to monitor the
effectiveness of the pumping system. It has been determined by data
collected from the four (4) corrective action monitoring wells and
the forty-three (43) monitoring wells that the ten (10) pumping wells
are successfully reversing the hydraulic gradient.
Data is collected from selected monitoring wells five (5) days, a week
and is used to insure that contaminated groundwater does not migrate
off-site. As shown in Figure 3, water level contours indicate a
continuous capture zone has been established across the southern
boundary of the facility.
In addition to Figure 3, data extracted from three consecutive
groundwater quarterly reports clearly demonstrate that the levels of
the contaminants of concern are decreasing with respect to time.
This data is shown in Table 4-1.
5.0 SITE RISKS
5.1 SUMMARY OF SITE RISKS
CERCLA directs that the agency must protect human health and the
environment from current and potential exposure to hazardous
substances at the site. In order to assess the current and potential
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ct-OGic*;. IHE«TMENI
SI >U« IMPOUNDMENT
MANUFACTURING
FACILITIES
PLATE 1. WATER-SURFACE (DYNAMIC)
OF ALLUVIAL AQUIFER.
JUNE 16. 1989.
FIGURE 3
EXPLANATION
ALLUVIAL WELLS
V PARTIALLY PENEIHATINO OBSERVATION MELL LOCATION ANO NUMBER
V FULLY PENETRATING OBSERVATION HELL LOCATION AND NUMBER
V MATER SUPPLY MELL LOCATION ANO NUMBER
V MONITORING MELL LOCATION AND NUMBER
0 OEMATER1NO MELL LOCATION ANO NUMBER
CORRECTIVE ACTION MONITOR I NO MELL LOCATION AND NUMBER
o-i
"a ABANDONED MATER SUPPLY MELL LOCATION AND NUMBER
II 70 SROUND-MATER SURFACE ELEVATION FEET HSL
MIOCENE HELLS
OBSERVATION NELL LOCATION ANO NUMBER
»>-1
A
\
'J
X
\5
MATER SUPPLY MELL LOCATION AND NUMBER
GROUND SURFACE CONTOUR. INTERVAL IS 10 FEET.
ICIBA-OEIBY DATUM)
EFFLUENT AND COOLINO MATER DITCN
MA1ER SURFACE CONTOUR. NOTE VARYING CONTOUR INIERVALS.
OAIUM IS MEAN EEA LEVEL
(DASHED MHERE INFERRED)
«o't »»u» UVK WIHINICI fwcifo ii
f. i IHWOM ».-i. p.-iv F.I i*>
Mill location coordlnidi provldid by Clbi-Gilgy CorporiUon
•tp> 0-895-00)5 18/22/84). D-995-0045 (6/22/84).
0-995-0071 19/3/65). ind 0-49879 119861.
SCALE IN FEET
•00 0 ICO |!>3 1100 >
-------
-12-
Table 4-1
Over Last Three Quarters
Alpha BHC
Ana line
Arsenic
Benzene
Cresols (-0-ra
Chlorobenzene
Chloroform
Lindane
Methel Ethyl
Naphthalene
*
**
***
*
**
***
*
**
*•*•*
*
**.
***
XP) *
**
***
*
**
***
*
**
***
*
**
***
Ketone *
**
***
*
**
***
CA 1
5.1
1.7
1.3
ND
ND
ND
11
BMDL
ND
ND
ND
44
ND
ND
ND
4700
59
860
410
6.4
150
0.6
0.27
0.3
ND
ND
ND
ND
ND
ND
CA 2
13
6.8
8.0
ND
ND
ND
7
BMDL
BMDL
43
29
22
ND
ND
ND
ND
78
76
ND
ND
20
ND
0.5
ND
ND
ND
ND
ND
ND
ND
(ug/i)
CA 3
ND
ND
ND
ND
ND
ND
145
94
104
15
13
11
ND
ND
ND
31
25
18
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
CA 4
ND
ND
ND
ND
ND
ND
30
10
18
ND
ND
ND
ND
ND
ND
ND
ND
5.2
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
ND
-------
-13-
Table 4-1
(continued)
Toluene
CA 1
* ND
** ND
*** ND
CA 2
1.0
ND
ND
CA 3
ND
5.6
ND
CA 4
ND
ND
ND
ND - None Detected
BMDL - Below Method Detection Limit
*** First Quarter '89
** Fourth Quarter '88
* Third Quarter '88
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-14-
Table 5-1
Hazardous Substances Found in the Groundwater
at the Clba-Geigy Site
Carcinogens
Aniline
Arsenic
Benzene
Alpha-BHC
Chloroform
Noncarcinoqens
^Gamma-BHC(Lindane)
Carbon tetrachloride
Chlorobenzene
Chloroform
Cresols(m-/p-)
Naphthalene
Methy ethyl ketone
Toluene
Maximum . Mean of Detected
Concentration fug/1) Concentrations fug/1)
150
196
8900
51
ndane ) 2 4
chloride 620
53
80
100
1200
10
10
290
40
24
620
230,000
53
18
12
63
5700
10
290
22,350
40
18
12
60
600
Data from the Comprehensive Monitoring Evaluation conducted by
ADEM, June 1988; all other data are from February, 1989 Quarterly
Samples.
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-15- . . .. • . •
risks from this site, a risk assessment was conducted as part of the
Remedial Investigation. The groundwater exposure pathway was not
addressed in that risk assessment because groundwater is currently
being remediated under the RCRA Corrective Active Plan. Therefore,
this section discusses the potential risk via the groundwater pathway
if the groundwater remediation program was discontinued.
The contaminants of concern in the groundwater were determined from
the 1989 First Quarter Groundwater Monitoring conducted by Ciba-Geigy
in February, 1989. The data from the pumping and observation wells
were used to select the groundwater contaminants of concern. The
risk assessment was based on both the maximum concentration detected
and the mean of each well containing a detectable level for each
contaminant of concern. Table 5-1 summarizes the contaminants of
concern and the maximum and mean concentrations.
5.2 EXPOSURE ASSESSMENT
The groundwater in the surficial aquifer in this area is classified
as a Class I aquifer based on EPA's Groundwater Protection Strategy.
This aquifer was originally classified as a Class II aquifer
indicating that the groundwater within the site classification review
area is either a current or potential source of drinking water, which
requires protection of human health. However, based on additional
site information the aquifer has been reclassified as a Class I
aquifer. This reclassification is based on the fact that the
groundwater at the site is highly vulnerable to contamination from
surface sources and discharges to a sensitive ecological system that
supports a unique habitat, which may present ah endangerment to the
environment.
As shown in Table 5-1, the surficial aquifer downgradient of the
hazardous waste facilities contains elevated levels of site related
hazardous constituents. Although the surficial aquifer was used at
one time to supply potable water for the plant, the potable water is
now supplied by either the river water reservoir or the deeper
Miocene Aquifer. Due to the fact that the surficial aquifer is no
longer being used as a source of potable water at the Ciba-Geigy
plant and that the ongoing Groundwater Corrective Action Program is
pumping and treating the contaminated groundwater, there does not
appear to be an immediate public health danger at this time from
groundwater consumption. However,. if the Corrective Action Program
was discontinued, there could be a future potential for exposure to
these hazardous constituents via the ingestion of contaminated
groundwater, which may pose an imminent and substantial
endangerment. According to the Remedial Investigation report, the
nearest downgradient domestic well is 1.9 miles to the south of the
facility.
Exposure assumptions in the risk assessment are that an exposed
individual consumes two liters of water daily for 70 years. Risks
resulting from this consumption level were determined .for exposure to
both the maximum and mean of the detected chemical concentration
levels.
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-16-
5.3 TOXICITY ASSESSMENT
Toxicity values are used in conjunction with the results of the
exposure assessment to characterize site risk. EPA has developed
critical toxicity values for carcinogens and noncarcinogens.
Cancer potency factors (CPFs) have been developed by EPA's
Carcinogenic Assessment Group for estimating excess lifetime cancer
risks associated with exposure to potentially carcinogenic
chemicals. CPFs, which are expressed in units of (mg/kg/day)~ ,
are multiplied by the estimated intake of a potential carcinogen, in
mg/kg/day, to provide an upper-bound estimate of the excess lifetime
cancer risk associated with exposure at that intake level. The term
"upper bound" reflects the conservative estimate of the risks
calculated from the CPF. Use of this approach makes underestimation
of the actual cancer risk highly unlikely. Cancer potency factors
are derived from the results of human epidemiological studies or
chronic animal bioassays to which animal-to-human extrapolation and
uncertainty factors have been applied. The CPFs for the carcinogenic
groundwater contaminants of concern at the site are contained in
Table 5-2.
Reference doses (RfDs) have been developed by EPA for indicating the
potential for adverse health effects from exposure to chemicals
exhibiting nonearcinogenic effects. RfDs, which are expressed in
units of mg/kg/day, are estimates of lifetime daily exposure levels
for humans, including sensitive individuals. Estimated intakes of
chemicals from environmental media can be compared to the RfD. RfDs
are derived from human epidemiological studies or animal studies to
which uncertainty factors have been applied (e.g., to account for the
use of animal data to predict effects on humans). These uncertainty
factors help ensure that the RfDs will not underestimate the
potential for adverse noncarcinogenic effects to occur. The RfDs for
the none arc inogenic groundwater contaminants of concern at the site
are contained in Table 5-2.
5.4 RISK CHARACTERIZATION
Human health risks are characterized for potential carcinogenic and
noncarcinogenic effects by combining exposure and toxicity
information. Excessive lifetime cancer risks are determined by
multiplying the intake level with the cancer potency factor. These
risks are probabilities that are generally expressed in scientific
notation (e.g., IxlO"5). An excess lifetime cancer risk of
lxlO~5 indicates that, as a plausiblr upper bound, an individual
has a one in one million chance of developing cancer as a result of
site-related exposure to a carcinogen over a 70-year lifetime under
-------
-17-
Table 5-2
Critical Toxicity Values and Risk Characterization for
Groundwater Contaminants at the Ciba-Geigy Site
Carcinogens
CPF
mg/kg/day
-1
Risk Level
max./mean cone
Proposed MCL
MCL for total trihalomethanes
Maximum
Concentration
Level
MCL
(ug/1)
Aniline
Arsenic
Benzene
Alpha- BHC
Gamma-BHC ( Lindane )
Carbon tetrachloride
Chloroform
Noncarc inogens
Gamma-BHC ( Lindane )
Carbon tetrachloride
Chlorobenzene
Chloroform
Cresols(m-/p-)
Methyl ethyl ketone
Naphthalene
Toluene
* None established
5.7 x 10"3
1.8 .
2.9 x ID"2
6.3
1.3
1.3 x 10"l
6.1 x ID'3
RfD
mg/kg/day
3 x ID"4
7 x 10"4
3 x 10-2
1 x 10-2
5 x 10-2
5 x ID"2
4 x 10-j-
3 x 10"1
2.4xlO"5./1.3xlO-5
9.9xlOr3/5.0xlO-3
7.2x10-3/9.7x10-4
9.0xlO-3/l.8xlO"3
8 . 7xlO"*/3 . 6x10"^
2.2x10-3/1.1x10-3
9.0xlO"6/6.8xlO-68
Hazard
Quotient
max/mean cone .
2.2/0.93
24.8/11.6
215./20.86
0.15/0.11
0.01/0.01
0.04/0.03
0.0008/0.0008
0.50/0.06
NE*
. 50.
'.-'.: 5..
NE
4. (0.2)
5 .
100***
. -' .< '"
MCL
(ug/1)
4. (0.2)**
5.
NE
NE
NE
NE
NE
2000
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-18- •,..•' .
the assumed specific exposure conditions at a site. The Agency
considers individual excess cancer risks in the range of 10 to
10"7 as protective; however, the midpoint risk (10~6) is
generally used as the point of departure for setting cleanup levels
at Superfund sites. This approach is consistent with Agency policy
for the implementation of SARA (Federal Register December 21, 1988,
Volume 53 No 245 51425). Table 5-2 contains the excess lifetime
cancer risks associated with the maximum and mean concentrations of
groundwater contaminants. This table also contains the concentration
equivalent to a 10 risk level. Potential concern for
noncarcinogenic effects of a single contaminant in a single medium is
expressed as the hazard quotient (HQ) (or the ratio of the estimated
intake derived from the contaminant concentration in a given medium
to the contaminant's reference dose). By adding the HQs of all
contaminants within a medium or across all media to which a given
population may reasonably be exposed, the Hazard Index (HI) can be
generated. The HI provides a useful reference point for gauging the
potential significance of multiple contaminant exposures within a
single medium or across media. Table 5-2 contains the hazard
quotients for the maximum and mean groundwater concentrations for
noncarcinogens. This table also contains the concentration that is
equivalent to the reference dose.
The cumulative carcinogenic risk level and the individual risk level
for many chemicals exceed the 10~"6 risk level for both the maximum
and mean exposure scenarios. In addition, the cumulative hazard
index and the individual hazard quotients for several chemicals
exceed unity for both scenarios. At the present time, individual
exposure via ingestion of contaminated groundwater is not occuring
due to the Groundwater Corrective Action Program. However, the
unacceptable risk levels indicate that the pump and treat program is
necessary to prevent the potential exposure to unacceptable levels of
contaminants in the groundwater in the future.
Actual or threatened releases of hazardous substances from the site,
if not addressed by implementing the response action selected in this
ROD, may present an imminent and substantial endangerment to public
health, welfare, or the environment.
5.5 CLEAN UP GOALS
Cleanup goals for groundwater remediation have been established for
the RCRA Groundwater Corrective Action Program. To remain consistent
with the RCRA Permit, Maximum Contaminant Levels (MCLs) or proposed
MCLs will be used as clean up goals for groundwater contamination.
Contract Required Quantisation Limits (CRQLs) will be used when MCLs
or proposed MCLs are not available. Standard analytical detection
limits (e.g. CRQL's) are appropriate as opposed to detection limits
requiring extraordinary analytical protocols. The Region has
discretion for long term remedial actions to say that detection
limits will change and must track the change on cleanup goals. Table
5.3 shows the cleanup goals for the contaminants of concern.
-------
Table 5-3
Clean Up Goals For Hazardous Substances
In Grounciwater At Ciba-Geigy Site
MGL- CRQL CLEAN UP GOAL
Chemical rug/ 11 fug/1)
Aniline , 10* 10
Arsenic 50 10 50
Benzene 5 5 5
Alpha - BHC .05 -O5**
Gamma BHC (Lindane) 4(0.2) .05 0.2
CarbonTetrachloride 5 5 5
Chlorobenzene . . 5 5
Chloroform 100 . : 5 5
Cresols (m-p-) 10 . 10
Methyl Ethyl Ketone 10 10
Naphthalene ^ 10 10'
Toluene 2000 5 2000
* Practical quantitation limit, as specified in the groundwater
monitoring list for the Appendix IX constituents, 52 Federal
Register, July 9, 1987. The PQLs will be used for chemicals not
on the Target Compound List.
** Proposed MCL
*** MCL for Total Trihalomethanes :
Contract - Required Quantitation Limit. (CRQLs) Chemical - specific
levels that a CLP laboratory must be able to routinely and reliably
detect and quantitate in specified sample matrices.
-------
. >20- :
6.0 DESCRIPTION OF ALTERNATIVES
The following alternatives for remediation were evaluated as a result
of the Remedial Investigation.
1. No Action
2. No further action (existing groundwater corrective action
program). .
6.1 Alternative fl No Action
Construction Cost $0
Annual Operation & Maintenance $0
The first alternative is no-action as required by Section 117(B),of
the National Contingency, Plan (NCP). This would entail shutting down
the existing groundwater Corrective Action Program, resulting in
reverting the groundwater flow direction toward the Tombigbee River,
increasing the likelihood of exposure via ingestion of groundwater
and enhancing the risk to aquatic life. The only reduction of
contaminant levels would be via natural processes such as dispersion.
6.2 Alternative #2 No Further Action (Existing Groundwater /
Corrective Action Program) >
Construction Cost 0
Annual Operation & Maintenance Cost $325,000
.•"•-' - , / _
This Alternative includes: ;.'•..'
* Continued use of the existing groundwater corrective action
program.
* Surface water discharge to Tombigbee River.
* Monitoring of effluent,, groundwater concentrations and pumping
rates. .
Alternative 2 involves the Groundwater Corrective Action Program
which is currently in operation at the Ciba-Geigy Corporation,
Mclntosh Plant. Groundwater is pumped from a 10 well pumping system
designed to intercept, remove, and treat contaminated groundwater
from the shallow alluvial aquifer. The water is being treated by the
plant's on-site biological wastewater treatment system (which
consists of neutralizers, pre-clarifiers, equalization, aeration,
chemical conditioning/ secondary clarifiers, sludge thickeners and
sludge dewatering) and discharged to the Tombigbee River along with
other treated wastewaters through the plant's NPDES permitted
discharge system. The on-site biological treatment system commenced
in September 1988, at a total cost of $72,000,000. The concept of
the waste water treatment system is to treat unit process waste
water, storm water and groundwater. The effectiveness of the
hydraulic barrier to movement of groundwater contaminants is well
established and contaminated groundwater is being withdrawn from the
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-21-
alluvial aquifer and treated at a rate of approximately 2 million
gallons per day.
At one time the shallow aquifer near the center of the plant was
being used to supply potable water to the Ciba-Geigy plant. However,
at the present time potable water is supplied by a surficial aquifer
well, located in the north plant property well which is upgradient of
active manufacturing or waste management operations. According to
collected data, the surficial aquifer downgradient of the site
contains elevated levels of site related constituents. The
cumulative carcinogenic risk level and the individual risk level for
many of these chemicals exceed the one in a million.risk level for
both maximum and mean exposure scenarios. Due to the fact that the
surficial aquifer is no longer being used as a source of potable
water at the Ciba-Geigy plant and that the ongoing groundwater
treatment system is pumping and treating the contaminated
groundwater, there does not appear to be an immediate public health
danger at this time. However, the unacceptable risk levels indicate
that continuation of the pump and treat program is necessary to
prevent potential exposure to unacceptable levels of contaminants in
the groundwater in the future, which may pose an imminent and
substantial endangerment to public health and the environment.
7.0 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
The major objective of this analysis is to provide the basis for
determining the most appropriate remedy with respect to the
evaluation criteria. A summary of the relative performance of both
alternatives with respect to the nine selecting criteria is listed
below, for those actions which meet ARARs and can achieve
protectiveness of human health and the environment. The "No Action"
alternative is not protective and therefore is not discussed in the
comparative analysis. The no further action alternative is on-going
and is the best means of achieving remediation. A nine criteria
discussion of this alternative follows.
7.1 IMPLEMENTABILITY
The implementability of an alternative is based on technical
feasibility, administrative feasibility and the availability of
services and materials. The alternative is readily implementable
using available materials and methods.
7.2 COST
There would be no construction cost associated with the No Further
Action alternative since the Corrective Action Program is already in
place. The annual operation and maintenance is estimated at $325,000
per year. No benefit could be provided by an alternative remediation
method which would be cost-effective for this operable unit as
compared to the No Further Action alternative.
-------
-22-
7.3 STATE ACCEPTANCE
The State has concurred in the remedy.
7.4 COMMUNITY ACCEPTANCE
The Community/ in general, favors the selection of the recommended
alternative for Operable Unit 1 of the Ciba-Geigy site.
7.5 PROTECTIVENESS OF HUMAN HEALTH AND THE ENVIRONMENT
The No Further Action alternative has demonstrated adequate
protection of human health and the environment by eliminating,
reducing or controlling risk through treatment, engineering controls
or institutional controls.,
7.6 COMPLIANCE WITH APPLICABLE OR RELEVANT AND APPROPRIATE
REQUIREMENTS
The existing groundwater corrective action program (No further
action) complies with applicable or relevant and appropriate
requirements. (See Section 9.2)
7.7 REDUCTION OF TOXICITY. MOBILITY OR VOLUME
The No Further Action alternative will continue to reduce the
toxicity, mobility, and volume of the groundwater contamination by
decreasing the size of the plume and/or eliminating part of the
source.
7.8 LONG-TERM EFFECTIVENESS
Long-Terra effectiveness and permanence will be provided by the No
Further Action alternative. Extraction and treatment of the sources
of contamination in the alluvial aquifer would produce a permanent
remedy. The No Action alternative is not effective in the long-term.
-------
-23-
8.0 SELECTED REMEDY
The preferred alternative for groundwater remediation at the
Ciba-Geigy site is Alternative 2 - No Further Action. EPA concurs
with the previous actions that have been taken to remediate the
alluvial aquifer by the Ciba-Geigy Corporation. It has been
determined from the data from the four (4) corrective action
monitoring wells and the 43 monitoring wells that the existing ten
(10) pumping wells are successfully reversing the hydraulic
gradient. Data is collected from selected monitoring wells five (5)
days a week and is used to ensure that contaminated groundwater does
not migrate off-site.
Based on current information and the analysis of the RI and other
related reports, EPA believes that the preferred alternative for the
Ciba-Geigy site is consistent with the requirements of Section 121 of
CERCLA and the National Contingency Plan. The preferred alternative
would reduce the mobility, toxicity, and volume of contaminated
groundwater on-site. In addition, the preferred alternative is
protective of human health and the environment, will attain all
Federal and State applicable or relevant and appropriate public
health and environmental requirements, is cost effective and utilized
permanent: solutions to the maximum extent practicable.
9.0 STATUTORY DETERMINATION
Under its legal authorities, EPA's primary responsibility at
Superfund sites is to undertake remedial actions that achieve
adequate protection of human health and the environment. In
addition/Section 121 of CERCLA establishes several other statutory
requirements and preferences. These specify that when complete, the
selected remedial action for this site must comply with applicable or
relevant and appropriate environmental standards established under
Federal and State environmental laws unless a statutory waiver is
justified. The selected remedy also must be cost-effective and
utilize permanent solutions and alternative treatment technologies or
resource recovery technologies to the maximum extent practicable.
Finally, the statute includes a preference for remedies that employ
treatment that permanently and significantly reduce the volume,
toxicity, or mobility of hazardous wastes as their principal
element. The following sections discuss how the selected remedy
meets these statutory requirements..
9.1 PROTECTIVE OF HUMAN HEALTH AND THE ENVIRONMENT
The selected remedy protects human health and the environment through
continued pumping and treating of the shallow alluvial aquifer. No
unacceptable short term risks will result from the implementation of
this remedy since the shallow aquifer is no longer being used as a
source of potable water.
-------
-24-
9.2 ATTAINMENT OF APPLICABLE OR RELEVANT AND APPROPRIATE
REQUIREMENTS
This remedy assures that the drinking water supplied to current or
future well users will meet available MCLs under the Safe Drinking
Water Act (SDWA) . For those chemicals which do not have assigned
MCLs, Contract Required Quantisation Limits (CRQLs) will be
attained. The CRQLs are in the to be considered (TBC) category.
Discharge from the groundwater corrective action system will meet
NPDES permit discharge limits under the Clean Water Act (CWA). The
CWA Section 121(d)(2)(b)(i) of CERCLA is an applicable requirement,
while the SDWA (MCLs) 40 CFR Part 141 and 142 and RCRA 40 CFR 268 are
relevant and appropriate. Land Disposal Restrictions (LDR) for
process residuals from the water treatment system is under a RCRA
permit and complies with this ARAR.
9 .3 COST EFFECTIVENESS
The recommended remedial alternative is cost effective. The
groundwater pump and treat system has been installed and is operating
effectively. The primary costs associated with this remedy are
operating and analytical costs.
9.4 UTILIZATION OF PERMANENT SOLUTIONS TO THE MAXIMUM EXTENT
PRACTICABLE
The U.S. EPA believes this remedy is the most appropriate cleanup
solution for the shallow alluvial aquifer at the Ciba-Geigy site.
This remedy provides effective protection in both the short and long
term to potential receptors. The system is in operation and data
shows that it is effective.
9.5 PREFERENCE FOR TREATMENT AS A PRINCIPAL ELEMENT
The statutory preference for treatment will be met because the
selected remedy treats the groundwater, one of the principal threats
posed by the site. The remaining operable units will address the
source of contamination and the deeper aquifer.
10.0 RESPONSIVENESS SUMMARY
The United States Environmental Protection Agency (EPA) and the
Alabama Department of Environmental Management (ADEM) established a
public comment period from August 30, 1989 through September 27, 1989
for interested parties to comment on EPA's and ADEM's Proposed Plan
for the remediation of the shallow groundwater aquifer at the
Ciba-Geigy site. A public meeting was conducted by EPA on Wednesday,
September 13, 1989. The public meeting was held at the Mclntosh Town
-------
...••. -25-
Hall in Mclntosh, Alabama. The meeting presented the studies
undertaken and the preferred remedial alternative for the site.
A responsiveness summary is required by Superfund policy to provide a
summary of citizen comments and concerns about the site, as raised
during the public comment period, and the responses to those
concerns. All comments summarized in this document have been
factored into the final decision of the preferred alternative for
cleanup of the Ciba-Geigy site.
This responsiveness summary for the Ciba-Geigy site is divided into
the following sections:
I. Overview This section discusses the recommended
alternative for remedial action and the public reaction
to this alternative.
II. Background on Community Involvement and Concerns This
section provides a brief history of community interest
and concerns regarding the Ciba-Geigy site.
Ill. Summary of Maior Questions Received During the Public
Comment Period and EPA's or ADEM's Responses This
section presents both oral and written comments
submitted during the public comment period, and
provides responses to these comments.
IV. Remaining Concerns This section discusses community
concerns that EPA should be aware of in design and
implementation of the remedy.
I. Overview;
The preferred remedial alternative was presented to the public in a
public meeting held on September 13, 1989. The recommended
alternative for remediation of the shallow groundwater aquifer is
presented in the Record of Decision (ROD). The major components of
the recommended alternative include:
Continued operation of the existing groundwater corrective
action program.
Continued monitoring of effluent, groundwater concentrations
and pumping rates.
Surface water discharge to the Tombigbee River.
The community, in general, favors the selection of the recommended
alternative.
-------
-26-
II. Background on Community Involvement and Concern;
The Mclntosh community and Washington County have been aware of the
contamination problem at Ciba-Geigy site for several years.
Ciba-Geigy semi-annually sponsors Open House tours for interested
citizens. Every three or four years a major site tour is held. The
last major tour was held in April 1989 and approximately 5000 people
took advantage of this service.
III. Summary of Malor Questions and Comments Recieved During
the Public Comment Period and EPA's or ADEM's Responses;
There were ho questions (written or oral) recieved during the comment
period. However, the Mayor of Mclntosh, Carroll Daugherty, expressed
positive comments and commended Ciba-Geigy for their time, efforts
and money used in research and construction of remediation activities
at Ciba-Geigy.
IV. Remaining Concernst
The community's concerns surrounding the Ciba-Geigy site will be
addressed by continuing community relations support until operable
units 2 and 3 have been completed.
Community relations should consist of making available final
documents in a timely manner, to the local repository, and issuance
of fact sheets to those on the mailing list to provide the community
with project progress and a schedule of events. The community will
be made aware of any principal design changes made during the
project. At any time during the remedial design or remedial action,
if new information is revealed that could affect the implementation
of the remedy, or, if the remedy fails to achieve the necessary
design criteria, the Record of Decision may be revised to incorporate
new technology that will attain the necessary performance criteria.
Community relations activities will be an active aspect of the
remaining phases of this project.
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.•(gti P*g.iMt. Director
! 751 Cong. W.L
)kkinson Drivt
vtontgomtry.AL
16130
I03/27V7700
:ield Off let*:
jnlt 806, Building 8
(25 Oxmeor CIrdt
llrmlnghtm. AL
ALABAMA
DEPARTMENT OF ENVIRONMENTAL MANAGEMENT
: September 28, 1989
Guy Hunt
Governor
zOs/ 442-61 6«
'.0. Box 9S3
5*
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