NCD980840409_20061001_Charles Macon Lagoon Drum_FRBCERCLA RA_Interim Remedial Action Report-OCR

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Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage Site
Cordova, Richmond County, North Carolina
EPA ID: NCO 980840409
Prepared for
US EPA Region 4
October 2006
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INTERIM REMEDIAL ACTION REPORT I CHARLES MACON LAGOON AND DRUM STORAGE SITE
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EPA ID: NCO 980840409
and the
State of North Carolina
Department of Environment & Natural Resources
&i~
NCDENR
-CA.Rot.,M ... lkr,oJ;n-NT 0,, E,.v,'"°"MO:NT..,.O ,.....,_...,...,_ RE.SOuf'a:S
Oclober 2006
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INTERIM REMEDIAL ACTION REPORT
RECORD OF PREPARATION, REVIEW, AND APPROVAL
CHARLES MACON LAGOON AND DRUM STORAGE SUPERFUND SITE
GROUNDWATER REMEDIATION
This report has been prepared in accordance with EPA OSWER Directive 9320.2-09A and will
be used as the basis for development of the site Final Close Out Report once groundwater
cleanup is complete
1
? 1 ~ RA Report .AJ
Prepared
By PRP Consultant: Steven lrminger, P.E. /President/ I.C., Inc.
r /'
8ctober I, 2006
RA Report -.~~
Submitted , .f{f rv!
By: PRP Agent: Ken B. Gulledge I Technical Lead/ MDSG
October I , 2006
Approved
By: EPA Region 4
Approving Official: Giezelle Bennett / Remedial Project Manager/
USEP A Region 4 Date:
Approved
By:
NCDENR
Approving Official: David Mattison / Environmental Engineer/
NCDENR Date:
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2.0
3.0
4.0
5.0
6.0
7.0
8.0
9.0
10.0
11.0
TABLE OF CONTENTS
INTRODUCTION ..
OPERABLE UNIT BACKGROUND .. . ..................... 5
2.1 Performance Standards .. . ........................... 5
2.2 Remedial Design
CONSTRUCTION ACTIVITIES
·······································································5
.................... 7
3.1 Installation of Recovery Wells .8
3.2 Installation of Groundwater Remediation Systems........ . ............. I 0
3.3 Start Up Performance and Sampling .................................................... I 3
CHRONOLOGY OF EVENTS .................................... 14
PERFORMANCE ST AND ARDS AND CONSTRUCTION QUALITY CONTROL ... 15
5.1 Groundwater Extraction System Effectiveness.... . .................................... 15
5.2 Quality Assurance and Quality Control ............................. 16
FINAL INSPECTION AND CERTIFICATION ................. 18
6.1 Inspections . 18
6.2 Health and Safety ........ 18
6.3 Institutional Controls ............................................................................................ 19
OPERATION AND MAINTENANCE ............. 20
7.1 Monitoring Activities ... 20
7.2 Maintenance Activities ........................................ 21
7.3 Closure Activities ........... .
7.4 Problems Encountered During the O&M Period .
7.5 Future Restoration Activities
SUMMARY OF PROJECT COSTS
OBSERVATIONS AND LESSONS LEARNED
CONTACT INFORMATION.
REFERENCES
LIST OF FIGURES
. .... 22
.23
··········· ... 24
········25
································27
.... 28
··········30
Figure I
Figure 2
Figure 3
Figure 4
Figure 5
Topographic Location Map
Upper Macon Source Area Diagram
Upper Dockery Area Diagram
Lower Dockery Area Diagram
Upper/Lower Macon Area Diagram
LIST OF TABLES
Table I Groundwater Performance Standards
LIST OF APPENDICES
Appendix A Site Characteristics, Operational Data
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Interim Remedial Action Report
Charles Macon Lagoon and Drum Slorage
Cordova. Richmond Coullly, NC
INTERIM REMEDIAL ACTION REPORT
CHARLES MACON LAGOON AND DRUM STORAGE SUPERFUND SITE,
CORDOVA, NORTH CAROLINA
EPA CERCLfS [D NUMBER EPA [D: NCD980840409
GROUNDWATER REMEDIATION
1.0 INTRODUCTION
The Charles Macon Lagoon and Drum Storage Site covers l7 acres on State Road I I 03 in
Richmond County, approximately 1.5 miles southwest of Cordova, North Carolina. A portion of
a United States Geological Survey Topographical map showing the site location is attached as
Figure I. The site is composed of the 16-acre Charles Macon Lagoon & Drum Storage site and
the I-acre Dockery site, which is located 2,600 feet north of the Macon site. A layout of the
Upper Macon site is provided as Figure 2 and of the Upper and Lower Dockery sites as Figures
3 and 4, respectively. A layout of the Upper and Lower Macon site is provided on Figure 5.
Land use in the area is agricultural, and woodlands cover over half of the site. The site overlies
an unconfined aquifer, and surface runoff discharges to the Pee Dee River, which is
approximately one mile west of the site. Between the site and the Pee Dee River are two ponds,
two streams, and a swamp.
From the late 1970' s to l 98 l, Charles Macon trucked in waste oil and recycled it at both the
Macon and the Dockery sites using a large boiler on the Macon site to separate the waste oil
from other wastes, including spent solvents, acids, and bases. Charles Macon leased five acres
of the Macon site, including the waste oil boiler, to another operator, C&M Oil Company of
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Interim Remedial Ac/ion Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond County. NC
Chesapeake, Virginia in May 1981. Starting at that time, C&M Oil Company arranged for trucks
from an affiliated company, B.W. Mitchum Trucking, also of Chesapeake, Virginia to haul waste
oil from other affiliated corporations in neighboring states to the Macon site and recycled it
there, continuing after Charles Macon died in October 1981. Then, in March 1982, when the
State of North Carolina sued C&M Oil Company and Charles Macon's widow and estate to
compel cleanup of waste oil residues, C&M Oil abandoned the site.
During a site inspection in 1980, the North Carolina Solid and Hazardous Waste Management
Branch (SHWMB) found 11 lagoons containing waste oil and sludge and 2,173 55-gallon drums
containing various chemical wastes. Eight of the lagoons were unlined and overflowing. The
State's analyses of the oil and sludge wastes in the lagoons found lead, chromium, and barium at
concentrations considered hazardous under the Resource Conservation and Recovery Act
(RCRA). The drums contained hazardous substances, which included acetone, methanol,
toluene, vinyl thinners, epoxy, enamels, lacquers, ethyl acetate, methylene chloride, and sodium
hydroxide.
In November 1982, the owner's estate started to clean up the site under a State court order
obtained by SHWMB in August 1982. After removal of 300 55-gallon drums and installation of.
two on-site monitoring wells, the estate's resources were expended. In November 1983, using
CERCLA emergency funds, EPA began to remove all remaining drums and excavated and filled
in all but one of the lagoons. The one unexcavated lagoon, designated lagoon number IO,
contained solidified creosote waste, solidified sludge, 43 crushed empty drums, and
contaminated soil from the cleanup operations at the other lagoons. Lagoon IO was then filled in
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and capped with 3 feet of clay.
Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Hichmond Co11111y. NC
In 1987, the MDSG members and six other potentially responsible parties (PRPs) entered a
consent decree with EPA reimbursing its response costs. In I 988, two of the MDSG members
signed an Administrative Order on Consent (AOC) agreeing to perform a Remedial Investigation
Feasibility Study (Rl/FS). These MDSG members completed the Rl/FS in 1991, and a final
cleanup option was selected in a formal Record of Decision (ROD) document for the Site agreed
to between EPA and the State in September 1991. In June, 1992, EPA issued an Unilateral
Administrative Order to eight of the PRPs to conduct the design and construction of the remedy
for groundwater at both the Macon and Dockery sites and for soil at lagoon 7 and lagoon IO on
the Macon site. Four of the eight PRPs that were named as respondents to the UAO formed the
MDSG, and collectively agreed to implement the Remedial Design and the Remedial Action
(RD/RA) The MDSG's Remedial Design was completed and approved by EPA in 1994, and its
construction of the Remedial Action was completed and approved by EPA in 1996. As of this
Interim Report, the MDSG has successfully operated and maintained the Remedial Action for ten
years, as further detailed below.
The soil remedy for Lagoon 7 was selected as vapor extraction. The remedy for lagoon IO was
expected to be in-situ bioremediation, however, subsequent treatability studies indicated that
bioremediation would not achieve performance standards. The ROD was amended in 1994 to
allow for the excavation and offsite disposal of the materials in lagoon 10. Removal and off-site
disposal of the remnants of lagoon IO was completed in October I 994.
Construction of the soil vapor extraction (SVE) system and the groundwater pump-and-treat
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Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond County. NC
systems were completed in January 1996. Both the SVE and groundwater remediation systems
were operational in February 1996. At the time of construction, the groundwater treatment was
expected to last approximately 30 years. A Five-Year Review was completed in 2000. The
review concluded that the SVE system could be terminated because the soils were successfully
remediated but the groundwater pump and treat systems should continue. The SVE system was
terminated in 2000 and all associated SVE equipment was subsequently removed. A second
Five-Year Review was completed in 2005. The review concluded that the groundwater pump-
and-treat system was operating as designed and should continue.
This Interim Remedial Acton Report has been prepared for the four groundwater pump and treat
systems across the sites that were required under the Operable Unit, three of which continue to
be actively operated. Operation of one groundwater remediation system (Lower Dockery) has
been suspended because the performance remediation standards have been achieved except
where exceedances were for certain inorganic parameters that were likely due to natural
background conditions as shown on the North Carolina Geologic Survey Maps.
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Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond County. NC
2.0 OPERABLE UNIT BACKGROUND
This section details development of cleanup standards and the remedial design for treatment of
groundwater.
2.1 Performance Standards
The groundwater remedy described in the ROD was designed to achieve performance standards
based on a risk assessment. The dominating risk assessment exposure scenario was residential
use of on-site groundwater. Performance standards or goals for groundwater were developed
based on the most stringent of State and Federal Maximum Contaminant Levels (MCL's) A list
of the groundwater performance standards is provided in Table I.
2.2 Remedial Design
The ROD called for treatment of groundwater by extraction and treatment by air stripping
followed by filtration. Treated water was then to be either drained to surface water under a
NPDES permit or to infiltration galleries.
The design for the groundwater remediation systems was completed by RMT, Inc. of Greenville,
South Carolina, and approved by the US EPA and NCDENR on June 28, 1994. The design for
groundwater remediation included four separate remediation systems which were designated:
Upper Dockery, Lower Dockery, Macon Source Area, and the Upper/Lower Macon systems.
The Upper Dockery and Macon Source Area systems were designed to extract groundwater
through the use of electric submersible pumps. The Lower Dockery and the Upper/Lower
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Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova. Richmond Co1111zv. NC
Macon Systems extract groundwater using jet pumps. All four systems were designed to use low
profile tray-style airstrippers. The Lower Dockery, and Upper/Lower Macon groundwater
I treatment systems included filtration for metals removal after air stripping. The number of
groundwater extraction wells at each site is as follows:
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• Upper Dockery: eight extraction wells
• Lower Dockery: five extraction wells
• Macon Source Area: five extraction wells
• Upper/Lower Macon System: 12 extraction wells
All of the systems were designed to discharge treated water to onsite infiltration galleries. In
February 1995, the U.S. EPA and the NCDENR approved the discharge of the treated water from
the air stripper directly to the infiltration gallery without treatment for manganese at the Macon
Source Area. Treatment for manganese and other metals was required for the Upper and Lower
Macon systems and the Lower Dockery system. All four of the treatment systems became
operational in February 1996.
A bioremediation pilot test was conducted in 1994 by DuPont Environmental Remediation
Services (DERS) in an attempt to determine the viability of inducing reductive dehalogenation of
dissolved chlorinated contaminants in the aquifer. Bench-scale testing indicated that the
indigenous microbes were capable of transforming PCE to vinyl chloride when supplied with
organic substrates, however, limited further degradation of vinyl chloride to ethene was
observed. Pilot testing in the field indicated that delivery of the substrate into the affected areas
was not economical. For this reason, bioremediation wa@ursued further as a remediation
technology.
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3.0 CONSTRUCTION ACTIVITIES
Interim Remedial Action Report
Charles Macon Lagoon and Dmm Storage
Cordova, Nichmond County. NC
This section describes the tasks conducted during construction of the selected remedy. The
construction of the four groundwater treatment systems began in the spring of 1995. The major
tasks and sub-tasks for construction activities (in approximate chronological order) were:
Contractor Selection Process
Bidder pre-qualification
Issue bid documents
Pre-bid conference
Review and Evaluate bids
Construction contract negotiations
Construction contract award and notice to proceed
Initial Sitework Construction
Contractor preparation and mobilization
Pre-construction conference
Site preparation -clearing, grading, access road construction
Construction of infiltration galleries
Well Installation
Installation of Groundwater Extraction Wells
Installation of S VE wells
Equipment Procurement
Air strippers
Vapor extraction blower moisture knock-out tank
Recirculation pumps
Submersible pumps
Transfer pumps
Instrumentation and controls
Treatment Systems
Form and pour concrete slabs
Placement of equipment on slabs
Trenching and installation of underground piping
Testing of piping and backfilling of trenches
Complete piping connections to wellheads
Complete piping to treatment equipment
Installation of electrical/instrumentation/controls
Electrical Inspection and Activation
Equipment operational testing
Final Inspection
System Start up and balancing
Site restoration and demobilization
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3.1 Installation of Recovery Wells
Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond Cou/1/y, NC
In July, August, and September I 995, RMT, Inc. oversaw the installation of 30 groundwater
extraction wells. The wells were installed by GZA, Inc. using the hollow stem auger drilling
method. The depths of the wells are as follows:
Well Designation Total Depth (feet)
LD-1 59.0
LD-2 58.0
LD-3 50.0
LD-4 52.0
LD-5 47.0
LM-1 69.30
LM-2 60.00
LM-3 81.50
LM-4 90.50
LM-5 86.50
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UD-1
UD-2
UD-3
UD-4
UD-5
UD-6
UD-7
UD-8
UM-I
UM-2
UM-3
UM-4
UM-5
UM-6
UM-7
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Interim Remedial Action Report
Charles Maco11Lagoo11 and Drum Storage
Cordova. Richmond Co1111tv. NC
84.00
83.00
87.00
94.0
82.50
79.00
80.50
80.50
59.50
67.30
32.20
50.00
36.50
55.80
54.50
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UMS-1
UMS-2
UMS-3
UMS-4
UMS-5
Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond County, NC
57.50
63.50
72.60
78.30
83.40
Following installation, the wells were developed by pumping and swabbing. Auger cuttings and
development water were drummed for characterization and disposal.
3.2 Installation of Groundwater Remediation Systems
Construction of the four groundwater remediation systems began in the spring of 1995. The
general contractor for the work was l-landex of the Carolinas, Inc. Construction occurred
simultaneously at all four sites and is detailed in the following sections. The equipment for the
four groundwater remediation systems is secured to a concrete slab with a gravel perimeter.
Each equipment compound is equipped with a 6-foot high chain link security fence and locking
gate. Electricity to the remediation compounds is supplied by Pee Dee Electric Company which
has a separate meter and pole for each system. Aboveground piping is protected from free~Mf
with the use of thermostatically actuated heat trace wiring and fiberglass wrap insulation.
Airstripper blowers are connected to thermostatically actuated air heaters which supply warm air
to the airstripper when the temperature falls below 40 degrees Fahrenheit. The systems are
reached by gravel roads which extend to the equipment compounds and all of the groundwater
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Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond County, NC
extraction wells. Performance requirements of the treatment system and design operating
characteristics for all of the groundwater remediation systems are contained in Appendix A.
3.2.1 Construction of Lower Dockery ,\'ystem
The Lower Dockery groundwater remediation system 111 1996 consisted of five
groundwater extraction wells which utilized jet pump technology. The jet pump system
uses a submerged venturi eductor to lift water out of the well. The venturi is created by a
single, aboveground, electric pump which circulates water through an underground pipe
laid in a loop to the farthest groundwater extraction well, through a turn-around pipe, and
back to a large aboveground storage tank at the remediation system. Water in the storage
tank is used to feed the circulation pump. Branch pipes lead from the main water supply
pipe to each of the wells. Each branch pipe is equipped with valves that assist with
setting up the venturi and balancing between wells. The eductors add groundwater to the
pipe returning to the storage tank. The excess water in the system is then allowed to
gravity drain from a bung near the top of the tank into a tray airstripper. The Lower
Dockery remediation system is equipped with a Shallow Tray brand low profile
airstripper. The airstripper process uses forced draft, countercurrent air through baffied
aeration trays to strip volatile organic compounds from water. The base of the airstripper
is equipped with a sump for collection of treated water. A float switch in the sump
actuates a centrifugal pump which then pumps the water through two canisters of metals
adsorbing resin operating in series and to an infiltration gallery located hydraulically
higher than the extraction wells. Particulate filters are located on the recirculation water
line which feeds the storage tank and in between the transfer pump and metals unit
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canisters.
Interim Remedial Ac/ion Reporl
Charles Macon Lagoon and Drum Storage
Cordova, Richmond Co11111y. NC
3.2.2 Construction of Upper/Lower Macon .\)>stem
The Upper/Lower Macon System consists of two jet pump extraction systems (designated
Upper Macon and Lower Macon, respectively) sharing the same treatment equipment.
The Upper Macon jet pump extraction system is connected to seven groundwater
extraction wells. The Lower Macon jet pump system is connected to five groundwater
extraction wells. Both extraction systems have their own water feed tank and are capable
of running independently of each other. Groundwater from each extraction system
gravity drains to a large Shallow Tray brand low-profile airstripper for treatment of
volatile organics. After the airstripper, the water is pumped through two resin canisters
for metals adsorption and then discharged to two infiltration galleries. Particulate filters
are located on the recirculation water lines which feed the storage tanks and in between
the transfer pump and metals unit canisters.
3.2.3 Con.,·truction of tlte Upper Dockery ,\'.iwtem
The Upper Dockery System utilizes an electric submersible pump placed into each well
to extract groundwater. The groundwater is pumped from the well through a common
header pipe to a large aboveground storage tank within the equipment compound
Groundwater drains from a bung near the top of the storage tank to a Shallow Tray brand
airstripper. Treated water is pumped from the airstripper sump to an infiltration gallery.
Particulate filters are located on the influent water line which feeds the storage tank and
in between the transfer pump and infiltration gallery.
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Interim Remedial Action Report
Charles Macon Lagoon and Dmm Storage
Cordova, Richmond County, NC
3.2.4 Con.~truction of the Upper Macon Source Area ,\'y.~tem
The Upper Macon Source Area System utilizes electric submersible pumps placed in the
extraction wells to pump groundwater through a common header pipe to the airstripper.
This remediation system configuration does not utilize a storage tank. Groundwater is
treated in a Shallow Tray brand airstripper and then allowed to gravity drain to an
infiltration gallery. A particulate filter is provided on the influent water line before the
airstripper.
3.3 Start Up Performance and Sampling
The Upper Dockery, Lower Dockery, and Macon Source Area remediation systems began
operation on February 12, 1996. The Upper/Lower Macon remediation system began operation
on February 21, 1996. During the first week of operation the influent and effiuent water was
sampled and analyzed on a daily basis to ensure that the treatment systems were performing as
designed. Start-up activities continued after the first week with monitoring and sampling
occurring each week for the first month of operation. Subsequent operation and maintenance
visits occurred weekly with monthly sampling of the effiuent No exceedances were reported
during the startup period.
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Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond County. NC
4.0 CHRONOLOGY OF EVENTS
The following table summarizes the major event and milestones for the groundwater treatment
systems ..
DATE EVENT
9/30/1991 ROD completed and signed
6/22/1992 US EPA issues an Unilateral Administrative Order (UAO)
06/01/1994 ROD Amendment signed
6/28/1994 Remedial Design completed
6/28/1994 PRP RA Begins
1/18/1996 Prefinal Inspection Report
02/1996 Superfund Preliminary Close-out Report (PCOR) complete
2/22/1996 SVE svstem at Lagoon 7 be!!ins operation.
2/22/1996 Groundwater remediation systems begin operation
11/06/1996 Preliminary Close-out Report Prepared
5/12/2000 Lagoon 7 Sample and Analvsis Plan Submitted to EPA
5/19/2000 USEPA aooroves Lagoon 7 Samole and Analvsis Plan
6/13/2000 Confirmation soil samples collected at Lagoon 7.
9/26/2000 Five Year Review complete
12/27/200 I S VE system at Lagoon 7 discontinued and wells abandoned
11/8/2002 Soil Vapor Extraction Abandonment Reoort Submitted to EPA
03/19/2004 Lower Dockery System suspended
9/28/2005 Five Year Review
I The Upper Dockery, Macon Source Area, and Macon Groundwater remediation systems
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continue to operate as originally designed. Influent concentrations of individual remedial
systems and concentrations of dissolved constituents of concern in water samples collected from
monitoring wells are observed for indications of becoming asymptotic or achievement of
performance standards.
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Interim Remedial Ac/ion Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond Co11111y, NC
5.0 PERFORMANCE STANDARDS AND CONSTRUCTION
QUALITY CONTROL
This section describes the performance of the prescribed remedy and data quality control
procedures for the groundwater remediation systems.
5.1 Groundwater Extraction System Effectiveness
The groundwater treatment systems are effective at removing and containing dissolved
contaminants at the four sites. The evidence for removal are the analyses of water samples from
the influent and effiuent p011s of each remediation system. To date, the total amount of
groundwater extracted, treated, and re-infiltrated at the site is as follows:
Groundwater Remediation Number of Gallons Treated
System (Through July I, 2006)
Upper Dockery 24,978,972
Lower Dockery* 27,170,253
Macon Source Area 24,644,307
Upper/Lower Macon 75,180,257
*System Suspended
The amount of dissolved contamination removed from the subsurface is quantified on a mass
basis. A summary of the mass of volatile organic contaminants removed follows:
Groundwater Remediation Mass of VOC's Removed
System (Pounds Through July 1, 2006)
Upper Dockery 29.01
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Lower Dockery*
Macon Source Area
Upper/Lower Macon
*System Suspended
Interim Remedial Action Report
Charles Macon Lagoon and Dmm Storage
Cordova, Richmond Co1111ty, NC
12.98
51.19
16.31
The technology was effective at the Lower Dockery site where the performance standards were
met and maintained for a period of one year in all monitoring wells, except for certain inorganic
parameters that were likely due to natural background conditions as shown on the North Carolina
Geologic Survey maps. It remains to be seen if similar results can be achieved at the three
remaining groundwater extraction sites in the future.
The evidence for containment is the consistent drawdown observed in the groundwater extraction
wells. Depth to water in groundwater extraction wells is measured on a weekly basis to assure
that each well is performing according to design.
I 5.2 Quality Assurance and Quality Control
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A Field Sampling and Analysis Plan (SAP) was developed in June 1994 and approved by the
EPA regarding sample control, field records, and chain of custody procedures to be followed at
the groundwater extraction systems.
Each system water or groundwater sampling point is provided a unique identification number.
Sample identification numbers were included on both the chain-of-custody forms and sample
containers. Sets of containers shipped together to the laboratory are assigned a chain-of-custody
form which travels with the sample containers. A copy of the chain-of-custody is kept by the
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sampler and the laboratory.
Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond Co11111y, NC
D The Field SAP includes decontamination procedures for groundwater sampling equipment and
detailed procedures for collection of groundwater samples from the monitoring wells.
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At least 14 days prior to sampling, the EPA's oversight contractor is contacted 111 order to
document the sampling event or split samples.
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Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond Countv, NC
I 6.0 FINAL INSPECTION AND CERTIFICATION
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These sections describe inspections by the EPA contractor, Health and Safety issues and
certifications for the groundwater remediation systems.
6.1 Inspections
Representatives from EPA, the design engineering firm (RMT), the engineering oversight firm
(Applied Earth Sciences, Inc.), and from the State of North Carolina were onsite during the
installation and start-up of the groundwater remediation systems. No deficiencies were noted by
the onsite oversight personnel.
Camp Dresser and McKee (CDM) was the EPA contract inspector for the collection of water
samples during the Operation and Maintenance phase The CDM inspector was contacted 14
days prior to each sampling event. The COM inspector documented that the water samples were
collected in accordance with the procedures contained in the SAP. No deficiencies were noted.
6.2 Health and Safety
A Heath and Safety Plan (HASP) dated June I 995 was prepared for remedial operations at the
I Macon and Dockery sites. The HASP covered Operation and Maintenance activities at
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groundwater systems and the soil remediation system. Work in the vicinity of the SVE system
was allowed with Level D personal protective gear. No substantial problems or deviations from
the HASP were noted.
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6.3 Institutional Controls
Interim Remedial Action Report
Charles Macon Lagoon and Drum Slorage
Cordova, Richmond Co1111tv. NC
Institutional controls were not required by EPA as part of the source control remediation
activities.
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7.0
Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond County. NC
OPERATION AND MAINTENANCE
The Upper Dockery, Lower Dockery, and Macon Source Area remediation systems began
operation on February 12, I 996. The Upper/Lower Macon remediation system began operation
on February 21; 1996. After the start-up period, routine Operation and Maintenance (O&M)
began. This section details the O&M tasks conducted at the site.
7.1 Monitoring Activities
Monitoring consists of collection and analysis of water samples from the influent and effluent
sample ports of each remediation system in addition to the collection and analysis of
groundwater samples from monitoring wells. The sampling frequency of system water samples
was initially every month. The initial sampling frequency of monitoring wells was quarterly.
Vapor samples were collected every quarter from the stacks of the airstrippers and from the
property line.
D The sampling frequency of the influent, effluent, and monitoring wells were changed after the
First Five-Year Review. The sampling frequency for influent and the monitoring wells was
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changed from quarterly to semi-annual. Vapor and effluent sampling was changed from monthly
to quarterly. Since quarterly sampling indicated that remedial goals for purgable aromatics were
achieved, the US EPA granted the MDSG permission in November 2003 to eliminate the
analysis of purgable aromatics from monitoring wells MW-11, MW-13, MW-16, MW-21, MW-
23, MW-24, and MW-25. Permission was also granted to eliminate the analysis of cadmium and
lead from monitoring wells MW-2A, MW-19, MW-21, MW-23, and MW-24 and the analysis of
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cadmium from wells MW-I 3 and MW-22.
Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond County. NC
D In a March 16, 2004 letter to a MDSG representative, the EPA granted the MDSG's request to
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suspend operation of the Lower Dockery system and to decrease the monitoring of wells MW-16
and MW-24 to quarterly. The EPA letter cited to the conclusion drawn by the NC DENR
Superfund Section that the exceedances that have been detected for inorganic constituents were
likely due to natural background conditions. The quarterly sampling was completed in May
2005 and groundwater from these wells is no longer sampled.
In February 2006, the US EPA granted the MDSG permission to change the frequency of well
sampling to annual.
7.2 Maintenance Activities
All of the remediation systems are inspected on a weekly basis. The weekly inspections include
recording airstripper sump pressure, totalizer meter readings, pressure differentials across bag
filters and the depth to water in each groundwater extraction well. Minor system maintenance
occurs during the weekly site visit and includes:
Change-out of bag filters;
Brushing of blower screens;
Changing oil in recirculation pumps;
Cleaning of flow meter screens;
Replacement of control panel light bulbs;
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Replacement of control panel fuses;
System troubleshooting;
Repair of minor leaks;
Interim Remedial Action Reporl
Charles Macon Lagoon and Dmm Slorage
Cordova, Richmond Co11111y, NC
Trimming of vegetation in and around the equipment compounds; and,
Preparation and Painting of corroded metal surfaces.
Repair of large diameter pipe leaks and major equipment pieces usually requires a non-routine
site visit.
7.3 Closure Activities
In February 2004, a request was made to suspend the operation of the Lower Dockery
groundwater treatment system. VOC's in the associated groundwater wells (MW-16 and MW-
24) had not exceeded the performance standards since 2001 and 1999, respectively.
Exceedances in several inorganic compounds (manganese, chromium, nickel, lead, vanadium,
and cadmium) have occurred in both groundwater monitoring wells. However, background
concentrations of these inorganics above performance standard levels have been documented in
stream sediment by the North Carolina Geological Survey (July 1993). Therefore, on March 16,
2004, approval was granted for the suspension of the Lower Dockery system with the
requirement that the groundwater wells, MW-I 6 and MW-24, were to be sampled quarterly until
it could be demonstrated that the remedial goals have been met for all constituents of concern for
four consecutive quarters. On March 19, 2004, the Lower Dockery system was suspended and
quarterly monitoring of the two monitoring wells initiated. In May 2005, the fifth quarter of
analyses from the two monitoring wells confirmed that all constituents of concern had met the
remedial goals for four consecutive quarters except for certain inorganics found as natural
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Interim Remedial Action Report
Charles Macon l.agoon and Dmm Storage
Cordova, Nichmond County. NC
background in the area, so EPA approved the suspension of this monitoring
7.4 Problems Encountered During the O&M Period
In spite of consistent and/or decreasing contaminant concentration, some exceedances have
occurred in the system effluents. Exceedances of metals performance standards, primarily
manganese in the effluent, has occurred periodically but is mitigated by cleaning the filtration
equipment and the fact that the extraction and treatment systems have been constructed as
closed-loop systems. VOC exceedances above performance standards rarely occur in effluent
samples and are generally indicative of the need for maintenance on the air stripper unit.
Overall, the three groundwater extraction and treatment systems are operating and functioning as
designed.
Exceedances of metals performance standards have been observed as a result of drought
conditions experienced during 2002 and 2003. During this period, the water table dropped below
the screen levels of some monitoring wells. As groundwater levels returned to normal, spikes in
metals concentrations were observed in water samples.
I Sediment in water samples has been observed to correspond with increased metals
I concentrations in water sample analyses. Low flow sampling techniques used at the Lower
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Dockery site in 2004 and 2005 were observed to reduce suspended solids and the metals
concentrations (particularly manganese) In the water samples collected.
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Interim Remedial Action Report
Charles Macon Lagoon and Drum Slorage
Cordova, Richmond Co11nly, NC
Literature searches of publicly available geological reports conducted in 2004 as part of the
request to turn off the Lower Dockery groundwater remediation system, documented that
background concentrations of manganese in groundwater of Richmond County North Carolina
are as high as 200 parts per billion (North Carolina Geological Survey, 1999)
I In I 995, the Upper Dockery infiltration gallery chronically flooded. As a result, a second
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infiltration gallery was placed into service at this site. Occasional flooding of the Upper Dockery
and Upper/Lower Macon infiltration galleries occurred in 1997. With approval from the US
EPA and the NCDENR, both infiltration galleries were treated with sodium hypochlorite in an
attempt to remove biological clogging from the gallery infiltration lines. No infiltration
problems have been observed since that time.
7.5 Future Restoration Activities
I No changes are anticipated at this time to the groundwater remediation systems. Continued
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groundwater extraction, treatment, and re-infiltration are expected for the foreseeable future.
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Interim Remedial Action Report
Charles Macon l.agoon and Drum .~'forage
Cordova, Richmond County. NC
8.0 SUMMARY OF PROJECT COSTS
Following the 1991 ROD, and the 1992 UAO, the MDSG set up a Fund to implement the
project. All group costs for the RD and RA since April 1993 have been paid through this Fund.
In the table on the next page are the costs estimated for groundwater remediation in the 1991
ROD and a comparison to actual groundwater remediation costs.
The O&M actual cost figures reported in the table are well below the -30% standard. This is
expected, however, because they cover only the IO years of operations to date (from the
February 1996 start up to the present), while the ROD projections are for a projected 30-year
operation of the groundwater treatment system ( 1996 through 2026.)
Further, the MDSG's accounting for its costs has not tracked the same categories as used in the
ROD cost projections, which made it difficult to do a direct comparison. We believe it likely, for
example, that some of the costs for the lagoon SVE system are included in the groundwater
remedy capital costs in the table below; this would artificially increase the actual groundwater
remedy costs repo,ted, and artificially lower the lagoon costs. Without this effect, both of those
reported actual costs would be closer to the ROD projections.
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Cost Item ROD Inflation Actual o/., Estimated
Estimate' Adjusted Cost3 Difference Gallons of
Rod Treated
Estimate2 Water
Capital Cost for $1,700,000 $1,955,000 $2,812,697 43.87% NA
Groundwater
Remedy
Operation & $5,200,000 NA $2,594,592 -50. 10% 151,973,780
Maintenance
Costs For
Groundwater
(ROD-30 yrs;
Actual-10 yrs)
Total Costs For $8,700,000 NA $6,454,038 -25.82% 151,973,780
Groundwater
(ROD-30 yrs;
Actual-I 0vrs)
All Inflation Adjusted and Actual costs are in 2006 dollars using an inflation rate of 3%
NA= Not applicable
1 ROD Costs are estimates, with present value calculated as of 1991.
2 Inflation adjusted at 3%/year for 5 years
Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage . .
Cordova. Richmond County, NC
Estimated Estimated Estimated
Pounds of Pounds of unit cost per
voe Inorganic pound of
Removed Compounds Contaminant
Removed Removed
NA NA NA
109.49 I 14.67 $] 1,574.73
109.49 114.67 $28,792.10
~ /\ctual Capital Cost does not include RD or RIFS; Actual O&M Costs are for the first 10 years of the 30 years estimated in ROD.
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Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond County, NC
9.0 OBSERVATIONS AND LESSONS LEARNED
• The groundwater extraction wells are equipped with underground vaults located near
each wellhead. The vaults contain valves, pressure gauges, and flow meters for the water
pipes entering and leaving the well. The vaults chronically fill with water intruding along
the pipe chases or from the surface after storm events. In addition, the valves and meters
are difficult to maintain without using a ladder to enter the vault. Furthermore, the flow
meters are not sensitive enough to discern a difference in flow between the supply and
discharge lines of each jet pump well and many of the pressure and flow gauges have
fouled in the damp environment of the vault. In retrospect, the use of the vaults is not
warranted for those wells utilizing electric submersible pumps and would have been
easier serviced at grade for those wells utilizing jet pumps.
• Thermostat controlled fans installed in the control panels have been successful at
preventing electronic malfunctions due to heat.
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10.0 CONTACT INFORMATION
Interim Remedial Ac/ion Heporl
Charles Macon Lagoon and Dmm Storage
Cordova, Richmond Co1111(v, NC
The Executive Committee Chairman for the MDSG was:
Thomas W. Daggett
Daggett Law Firm
Suite 4950 -Chicago Title Tower
161 North Clark Street
Chicago, IL 60601
The MDSG used the following consultant for design of the RA:
Paul Furtick
RMT, Inc.
I 00 Verdae Boulevard
Greenville, SC 29607
[phone]
The MDSG used the following contractor for implementation of the RA:
John Canzeri
Principal Hydrogeologist
Handex, Inc.
3600-G Woodpark Boulevard
Charlotte, NC 28206
[phone]
The MDSG used the following contractor for engineering oversight of the RA:
Dan Arner
Applied Earth Sciences, Inc.
434 Copperfield Blvd.
Concord, NC 28025
[phone]
The EPA used the following contractor for oversight of the RA:
Mike Profit
CDM Federal
2030 Powers Ferry Road
Atlanta, Georgia 30339
The following company analyzed samples for the MDSG:
Savannah Environmental Laboratories, Inc.
5102 LaRoche A venue
Savannah, Georgia 3 1404
(912) 3 54-7858
The Project Manager for the M DSG was:
Ken Gulledge
Crown, Cork, and Seal, Inc.
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I 00 Evans Row
Cheraw, South Carolina 29520
[phone]
The Remedial Project Manager for the EPA was:
Giezelle Bennett
U.S. EPA Region 4
61 Forsyth Road SW
Atlanta, Georgia 30303
( 404) 562-8824
The Project Manager for the NCDENR was:
David Mattison
40 I Oberlin Road -Suite I 50
Raleigh, North Carolina 27605
[phone]-
,;-o g -'ti 4 L, l,
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Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova, Richmond County, NC
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11.0 REFERENCES
Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova. Richmond County. NC
List of Documents Reviewed
Charles Macon Lagoon and Drum Storage Site
Interim Remedial Action Report
Groundwater Remediation
Sirrine Environmental Consultants, Inc., February 1991. Remedial Investigation Report,
Charles Macon Lagoon and Drum Site, Cordova, North Carolina
Sirrine Environmental Consultants, Inc., July 1991. Final Feasibility Study,
Macon/Dockery Site, Richmond County, North Carolina
U. S. Environmental Protection Agency, Region IV. July 25, 1991. Proposed Plan
Superfund Fact Sheet. Charles Macon Lagoon and Drum Site, Cordova, North Carolina.
U.S. Environmental Protection Agency, Region IV. September 30, 1991. Record Of
Decision, Charles Macon Lagoon and Drum Site, Cordova, North Carolina.
U. S. Environmental Protection Agency, Region IV. June 1, 1994. ROD Amendment,
Charles Macon Lagoon and Drum Site, Cordova, North Carolina.
RMT. Inc , June 1994. Workplan for the Removal of Wastes from Lagoon 10,
Vessels, and Drums, Macon/Dockery Site, Cordova, North Carolina
RMT, Inc., June 1994. Field Sampling and Analysis Plan, Macon/Dockery Site,
Cordova, North Carolina
RMT, Inc., January 30, 1995. Removal Action Completion Report, Charles Macon
Lagoon and Drum Site, Cordova, North Carolina
RMT, Inc., February, 1995. Final Remedial Design Report, Charles Macon Lagoon
and Drum Site, Cordova, North Carolina
Handex of the Carolinas, June 1995. Site Health and Safety Plan, Charles Macon
Lagoon and Drum Site, Cordova, North Carolina
U.S. Environmental Protection Agency, Region IV. January 2000. Close Out
Procedures for National Priorities List Sites
Applied Earth Sciences, Inc., May 12, 2000. Revised Sampling and Analysis Plan;
Lagoon 7, Charles Macon Lagoon and Drum Site, Cordova, North Carolina
U. S. Environmental Protection Agency, Region IV. September 26, 2000. Five-Year
Review Report, Charles Macon Lagoon and Drum Site, Cordova, North Carolina.
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Interim Remedial Action Report
Charles Macon Lagoon and Drum Storage
Cordova. Richmond Coullly, NC
Applied Earth Sciences. Inc., October 3, 2000. Soil Assessment Report-Former
Lagoon 7. Charles Macon Lagoon and Drum Site, Cordova. North Carolina.
Applied Earth Sciences, Inc., September 12, 2002, Soil Vapor Extraction Abandonment
Report, Charles Macon Lagoon and Drum Site, Cordova, North Carolina.
U. S. Environmental Protection Agency, Region IV. September 2005. Five-Year
Review Report, Charles Macon Lagoon and Drum Site, Cordova, North Carolina.
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FIGURE 1
Topographic Location Map
Macon Dockery Site -Cordova, Norfh Caroiina
0.2 0.4 0.6 0.8 1 ll'li
Map center is UTM 17 606 I 88E 3862309N (WGS84/NAD83)
Rockingham quadrangle -TopoZonc Pro elevation display
Projection is UTM Zone 17 NAD83 Datum
M=-7.681
G=0.665
- --- - - - - - - - - - - - --l!l!!I i=:t
aJ
~ __ ....,,."'!!""'!e! __ _
,I l===...,;;;L.,;B..,G;;,.,;;B..,;N...,;;;D~--1
MW-3
MW-05
UIIS--4 @ MW-OBA
UIIS-! @ @ MW-08
Tn,n,:h/lna ~ 11 ~~~~ 6
'-MW-02A
-3-::::-~~~~
@
MW-01 ~
~
"" IIIIH
Galla,y
@ @MW-02
UMS-2 @ MW-07
l~-00
UII @
'-'
® Monitor Well Location 0 ,~~==~==~======::;==~====~~~
IRMINGER CONSULTING, INC.
I'\) -IIJ,t SEI -01-:20-2005 0004-001 Clrkd /Jp SEI ,_ 000-400!
MACON DOCKERY SITE CROUP UPPER 1llA CON SOURCE AREA 2
-------------------
Air tl.ltHIH
® MW-15A
0
llp,,.r Dochry
Tr«lfmMlf Spl9m
a ♦
! W N LEGEND 1
:I! ® Monitor Well Location Not To Seals l~~==~=~====~=~=====~~d
IRMINGER CONSULTING, INC.
0004-001 -lip SD -Ol-20-2005
Cllttlllp SE ,_,_ 0004001
M'ACON DOCKERY SITE GROUP UPPER DOCKERY 3
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IIW-21
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,_ 0 Monitor Well Location ;~~==~~=======r~~~, IRMJNGER CONSULTING, INC. MACON DOCKERY SITE LOWER DOCKERY 4
_,,..SEI -Dl-211-1999 GROUP 0004-00 _, ljr SEI ,_ Fll.ENAIIE
UM-8
UM-5
® MW-21
"" ! .-=....,,e":'===-:""":"--"'I
k P----=L==B .. G .. B;;,,,;;,N._D...__==-1
MW-23 ®
Lagoon ff
MW-12 ®
IJ
£Lagoon 10
®:w;J -•
LM-5
-1• ~ \( ~-•
,------,LM-3
-2
'Iii ® Monitor Well Location
J~~=~~~==:;;;:=====~~=r===========,====J
® MW-22
ffiMINGER CONSULTING, INC.
(11 -/ly: SEI -01-20-2005 0004-001 CMd /ly: SEI ,_,,,,, OCJ0.400I
MACON DOCKERY SITE GROUP UPPER/LOWER MACON 5
liilil liiiiii liiiiil - - - - - - - - - - - - - - - -
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TABLES
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TABLE I
GROUNDWATER PERFORMANCE STANDARDS
CONTAMINANT REMEDIATION
LEVEL
(ug/1)
Tetrachloroethene 1
Trichloroethene 2.8
1, 1-Dichloroethene 7
1,2-Dichloroethene 70
Vinyl chloride 1
Benzene 1
1, 1, 1-Trichloroethane 200
Manganese 50
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APPENDIX A
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CHARACTERISTICS AND SITE CONDITIONS
Parameter Site Conditions Measurement
Procedure/
Comment
Environmental Settine
Air Temperature Average July Average= 80° F Rockingham Weather
Janu~rv Avera2:e = 40° F Undernround
Range of Average August Morning Average = Rockingham Weather
Humidity 90% Underground
April Afternoon Average =
48%
Range of Average Monthly July average= 6 inches Rockingham Weather
Rainfall (inches) April average = 3 inches Underground
Soil Tvves
Soil Classification. Cecil and Iredell Soils of the USDA
Piedmont Province and
Norfolk, Orangeburg, and
Greenville soils of the Coastal
Plain Province
Geology Saprolite consisting of silts and
clays overlying a granitic
bedrock separated by a thin
transition zone.
Denth to groundwater 20 to 35 feet below <>rade
Operating Parameters
Parameter Site Conditions Measurement
Procedure/Comment
Lower Dockery Flow Rate 8-10 Totalizing F]ow Meter
(onm)
Upper Dockery Flow Rate 6-10 Totalizing Flow Meter
fonm)
Macon Source Area Flow 4-8 Totalizing Flow Meter
Rate (onm)
Lower Macon Flow Rate 8-12 Totalizing Flow Meter
(<mm)
Upper Macon Flow Rate 14-20 Totalizing Flow Meter
(onm)
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Lower Dockery Airstripper
Sump Pressure
Upper Dockery Airstripper
Sumo Pressure
Macon Source Airstripper
Sump Pressure
Upper and Lower Macon
Airstriooer Sumo Pressure
Lower Dockery
Recirculation Pump
Pressure
Lower Macon
Recirculation Pump
Pressure
Upper Macon
Recirculation Pump
Pressure
Differential pressure across
all bag filters
Lower Dockery Blower
Air Flow Rate
Upper Dockery Blower Air
Flow Rate
Macon Source Blower Air
Flow Rate
Upper and Lower Macon
Blower Air Flow Rate
12 inches water gauge Magnehelic mounted on
airstriooer
14 inches water gauge Magnehelic mounted on
airstriooer
10 inches water gauge Magnehelic mounted on
airstriooer
9 inches water gauge Magnehelic mounted on
airstrioper
120 psi Pressure gauge on pump
100 psi Pressure gauge on pump
120 psi Pressure gauge on pump
<4 psi Differential pressure gauge
across bag filter
120 CFM Velocity by Pitot tube and
Magnehelic multiplied by
duct cross section.
90CFM Velocity by Pitot tube and
Magnehelic multiplied by
duct cross section.
I 10 CFM Velocity by Pitot tube and
Magnehelic multiplied by
duct cross section.
190 CFM Velocity by Pitot tube and
Magnehelic multiplied by
duct cross section.