NCD122263825_20000714_JFD Electronics - Channel Master_FRBCERCLA RD_Method of Construction Plan-OCR

I
I
I
I
I
I -~
1 .cf: Method of Const~ction Plan
1 (J) for JFD Electronics/Channel
1 J! Master Site
I I Co~
·~ Prepared for:
ARCADIS Geraghty & Miller, Inc.
2301 Rex woods Drive
Suite 200 I rn;~ \j~ Raleigh, North Carolina 27607 @ Site: I
I
I
I
I
I
I
.• ~ Soil/Sludge Remedial Action: Excavation and On-Site Remediation
JFD Electronics/Channel Master Site
Prepared by:
Earth Tech, Inc.
7870 Villa Park Drive
Suite 400
Richmond, Virginia 23228
July 14, 2000
Earth Tech Project No. 41105
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
Table of Contents
1.0 INTRODUCTION ............................................................................................................................. I
1.1 Scope of Work ............................................................................................................................... I
2.0 GENERAL PROVISIONS ................................................................................................................ I
3.0 WORK SEQUENCE .... , .................................................................................................................... 2
3.1 Erosion and Sediment Controls ..................................................................................................... 2
3.2 Contractor Staging Area ................................................................................................................ 3
3.3 Clearing and Grubbing ................................................................................................................... 3
3 .4 Excavation ..................................................................................................................................... 3
3.5 Hauling and Stockpiling ................................................................................................................ 4
3.6 Backfilling ..................................................................................................................................... 4
3.6.1 Structural Fill ............................................................................................................................. 4
3.6.2 Vegetative Soil ........................................................................................................................... 5
3.7 Grading .......................................................................................................................................... 5
4.0 CONCLUSION ................................................................................................................................. 5
ARCADIS I JFD Work Procedures I C:UFD ELECTRISUBMITTALS\02200\WORKPROCEDURESJFDFINAL.DOC I July 17. 2000 i
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
1.0 INTRODUCTION
This Method of Construction Plan has been prepared by Earth Tech, Inc. for ARCADIS Geraghty &
Miller, Inc. (ARCADIS). This document provides Earth Tech's site-specific construction approach for the
JFD Electronics/Channel Master Site located in Granville County, Oxford, North Carolina. This Plan has
been prepared pursuant to Specification Section 02200 contained in the May 2000 Final Contract
Documents and the United States Environmental Protection Agency's (EPA's) Record of Decision (ROD)
dated September, 1992, and ROD Amendment dated May 1999.
I.I Scope of Work
The original scope of work from the Final Design Report (FDR) includes but is not limited to the following:
I.
2.
3.
4.
5.
6.
7.
8.
9.
JO.
11.
Excavating soils and sludges from designated areas, and hauling, loading and/or stockpiling for on-
site treatment or off-site treatment and disposal;
Excavation of on-site soils for use as backfill;
Excavation and stockpiling of unimpacted soils from the area near well CMMW 15 for use as
structural fill;
Construction of the earthen berms, retaining walls and diversion ditches;
Construction of temporary access roads;
Consolidation of treated soils in designated areas;
Installation of Contractor staging areas;
Cover system foundation preparation and site grading;
Furnishing, hauling, testing, placing and compacting structural fill as required in excavation areas;
Furnishing, hauling, testing, and placing vegetative soils; and
Permanent seeding in all disturbed areas.
Sampling efforts made by ARCADIS on May 24 and 25 show that the volume of metals-impacted soil is
significantly less than estimated in the FDR. Therefore, the remedy is being amended by an Explanation of
Significant Difference from the EPA. The amendment will allow the metals-impacted soil to be treated and
disposed of off site instead of on-site stabilization and backfilling on site. This will eliminate the need to on
site treat the metals-impacted soils that contain metals concentrations above remediation levels, eliminate
the cover system for the treated soil that was to be backfilled, and eliminate the need for any retaining wall
structures.
Another change from the original scope of work is the stockpiling of cyanide-impacted soil/sludge to be
loaded and transported off site. Per discussions at the Pre-Construction Conference on June 12, 2000,
instead of "live" loading this material into transportation containers (e.g., roll-off boxes, trucks, rail cars),
the material can be stockpiled. The stockpile will be approximately one day's worth of excavation or 200
CY.
2.0 GENERAL PROVISIONS
Earth Tech will furnish all materials, labor, tools, equipment and transportation necessary to perform the
work as shown in the Specifications and Drawings. The work will be done in accordance with all
Contract documents.
ARCA DJS I JFD Work Procedures I C.-VFD ELECTR\SUBMIITALS\02200\WORKPROCEDURESJFDFJNAL.DOC I July 17. 2000 I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
No soils shall be removed from site by Earth Tech unless directed by ARCADIS. No off-site fill or on-
site fill material shall be placed as backfill unless it has been previously accepted, and/or approved by
ARCADIS. No materials shall be backfilled when either the material or the surface on which it is to be
placed is frozen. No backfilling or excavation shall take place during precipitation unless approved by
ARCADIS. No backfilling or excavation shall take place after rain events unless conditions are
acceptable and approved by ARCADIS. Earth Tech will dewater as necessary to meet the performance
standards as set in the Specifications. Necessary equipment including but not limited to a trash pump
will be used for dewatering.
General soil materials will be placed in such a manner to facilitate drainage at all times. Ponding of
surface-water run-off will not be allowed.
Off-site structures, utilities, roadways, streams, and other facilities will be protected from hazards of the
earthwork activities and deliveries for the site.
Earth Tech will use properly sized equipment to perform all work. All equipment will be
decontaminated before leaving the site and before it contacts clean material after handling contaminated
material.
3.0 WORK SEQUENCE
The following sections will show in general order the sequence of work and methods of construction.
3.1 Erosion and Sediment Controls
Earth Tech will start implementing erosion and sediment controls concurrently with setting up the
contractor staging areas. Earth Tech will use an excavator to build diversion berms along the west side
of the site from the northwest comer of the BANDAG metal building to the treatment tanks. The exact
location will be determined in the field so that the particulars of the existing grade can be addressed. The
berm will be made of on-site soils to a minimum 2 feet high with a one-to-one slope on the sides and a 2
percent on the top. The berm will be seeded per Specification Section 02936, Temporary Seeding
Requirements.
Silt fence will be placed per Specifications and Drawings. A walk-behind trencher will be used to
embed the fabric and wire a minimum of 8 inches in the ground. Steel post will be place at a maximum
of 10 feet apart to support the fabric and wire. Additional silt fence may be placed where prudent. Silt
fence will be inspected regularly and after rain events to ensure that it is working properly and to see if
repairs or adjustments are required.
Riprap will be placed by an excavator as needed to form check dams. Sediment trap(s) may be made by
an excavator as necessary to manage stormwater. Riprap will be used at the outlet of the sediment
trap(s) to help filter and control sediments.
Streams will be protected and/or diverted as necessary. This will done in a manner to limit the amount of
sediment put into the stream by using riprap, silt fence and/or other measures.
ARCADIS I JFD Work Procedures I C:VFD ELECTR\SUBM11TALS\02200\WORKPROCEDURESJFDFINAL.DOC I July 17. 2000 2
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
Clearing, grubbing and excavation activities will not commence until erosion and control measures are in
place.
3.2 Contractor Staging Area
Earth Tech will improve and install a temporary access road from the road through the contractor staging
area to the excavation areas. The road will consist of geotextile and crushed stone, NCDOT type ABC.
The road will help facilitate transportation for site deliveries, loading and transportation for off-site
disposal, and transportation for stockpiling. There will be an entrance path into the contractor staging
area and an exit path that routes through the decontamination pad. The decontamination pad will be
placed on a base of ABC stone at a location that will provide efficient flow of traffic and allow access to
the two northernmost bays of the BANDAG building as requested by the OWNER. The
decontamination pad will be constructed per drawings with 6" of asphalt, 8" curbs and a 3' diameter 3'
deep sump. A poly tank will be placed to hold clean water and another tank will be used to hold decon
water from the sump. A pressure washer and hand tools will be used to clean trucks and other equipment
leaving the site. Stockpiles will be placed in the staging area per the Stockpiling Plan. Also, other
materials and equipment may be stored in the staging area as necessary.
3.3 Clearing and Grubbing
Earth Tech will use a chain saw and other hand tools to remove shrubs, trees and other large vegetative
growth from areas that are to be excavated or used for access. This material will be disposed of off site
along with stumps and large roots. An excavator will remove the top 6" of soil. The soil will be placed
in a stockpile for further disposition as directed by ARCADIS. Stumps, large roots, rocks and other
foreign matter will be removed and disposed of properly.
3.4 Excavation
The excavation will be done by an excavator in areas and to depths as directed by ARCADIS. The
excavation will proceed generally from west to east, working towards the contractor staging area to limit
cross contamination. The excavator will load metals-impacted soil and cyanide-impacted soil/sludge
directly into a dump truck for placement in the load-out stockpile. Suspect soils, soil around the sludge
drying beds and other soil that may be below the remediation levels for the constituents of concern
(COCs), will be excavated and placed so that it can be placed into a dump truck by a loader or shuttled
with a loader to haul this material to the designated stockpiles. The excavator bucket will be "dry"
decontaminated between excavating contaminated material and suspect material. The "dry"
decontamination will involve using scaping tools and brushes. The suspect materials will be placed
behind the excavator on ground that is to be excavated later to avoid cross contamination. No excavated
suspect soils will be left outside the designated stockpiles during rain events or after work hours.
Excavated refuse and debris will be disposed of at the direction of ARCADIS.
Earth Tech will provide proper trenching and excavation techniques to protect nearby structures, prevent
sidewall collapses, and to have safe site conditions. Any excavations over 4 feet will be considered a
confined space and permit. procedures will be required. If necessary, sheeting and shoring or other
methods will be implemented.
Earth Tech will limit the amount of surface run-off that will enter the excavation area. However, if there
is standing water in the excavation, dewatering will be done. Backfilling will be done as soon as
ARCADIS I JFD Work Procedures I C,VFD ELECTR\SUBMIITALS\02200\WORKPROCEDURESJFDFINALDOC I July 17. 2000 3
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
practical once the area of the excavation is confirmed "clean" by ARCADIS. During rain events and the
end of each day's work, the open face of the excavation will be covered with 6-mil poly sheeting and an
earthen dam placed against it to limit any water contact with soil to be excavated. Water in the
excavation will be pumped out in such a manner as to limit any sediment being discharged. If water
comes in contact with contaminated soil it will be pumped directly into a container for testing. Based on
the testing, this water will be used for dust control or disposed of as directed by ARCADIS.
Dust control will be done using a water truck or hoses directly from a fire hydrant. Dust monitors
(Minirams) will constantly monitor fugitive dust. If the monitors show dust levels that require action
levels as shown in the Site Health & Safety Plan, then measures will be taken as required including but 'I\
not limited to engineering controls.
Caution tape and/or safety fence with warning signs will be placed around open excavation areas at the
end of each day.
Earth Tech will excavate on-site materials for structural backfill using an excavator. The material will be
transported to areas to be backfilled using a dump truck, loader, or bulldozer depending on the location
of excavation relative to the area where it will be used. The areas to be excavated will be determined by
ARCADIS. Once an area excavated for fill is finished, it will be graded to promote positive site drainage
and seeded per Specifications.
3.5 Hauling and Stockpiling
The transporting of excavated materials on site will be done using a dump truck and a rubber tire loader.
Haul routes will be placed to the greatest extent possible over areas to be excavated in order to limit the
potential for cross-contaminating "clean" areas. Every effort will be made to avoid spillage and dust
emissions from equipment transporting contaminated and/or suspect soils.
Every vehicle used to transport contaminated soil off site will be washed at the decontamination pad
before leaving the site. If contaminated material is deposited in the roadway or other area outside the
exclusion zone, it will be promptly removed and placed in the transport vehicle or designated stockpile.
Stockpiling will be done according to the submitted and approved Stockpiling Plan.
3.6 Backfilling
Earth Tech will provide suitable off-site material for structural fill and vegetative soil. The materials
will pass all requirements in the Specifications Section 02200. Limited on-site structural fill will be
excavated as directed by ARCADIS. Prior to backfilling, the excavation areas will be free of stones,
limbs, or other debris. Fill material will not be placed over a lift that has not been approved by
ARCADIS. Earth Tech will make adjustments and repairs as necessary to perform work to the quality
standards set in the Contract Documents including the CQA Plan.
3.6.1 Structural Fill
Structural fill will be used to backfill excavation areas, fill low-lying areas, construct berms and
construct ditches. Structural fill will be placed in a maximum 12 inches compacted lifts. An appropriate
size compactor (greater than IO tons) will be used to compact the lifts to achieve the required 90 percent
ARCADJS I JFD Wo,k Pwcedum I CVFD ELECTR\SUBM!rTALS\02200\ WORKPROCEDURESJFDFINAL.DOC I July 17, 2000 4
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
of maximum dry density as determined by ASTM D-1557. The moisture content will be between
percent below and 3 percent ab9ve the optimum moisture content as determined by ASTM D-1557.
Water will be added if moisture is needed and the soil will be scarified and air-dried if the moisture
content is too high. Testing will be done at a rate of three per lift or as directed by ARCADIS. Any
values outside the parameters stated above will be handled per Specification Section 3.04 D. Earth Tech
will test the in-place density and moisture of the structural fill with ASTM D-2922 and ASTM D-3017
respectively. Every 25th test will be verified with ASTM D-1556 and ASTM D-2216, respectively.
Backfill will begin as soon as practically possible in areas that are approved by ARCADIS. This will
help limit water ponding in the excavation areas and expedite the project schedule.
3.6.2 Vegetative Soil
Vegetative soil will be used over disturbed areas and areas filled with structural fill. Soil mixing, if
needed, will be done prior to placing the soil. Vegetation and other foreign material will be removed
from the areas to receive vegetative soil. The surface of the ground to receive vegetative soil will have
smooth grades and slopes so as to not interfere with the placement of the vegetative soil. The areas to
receive vegetative soil will be scarified at least 3 inches using the tracks of heavy equipment or other
suitable means to ensure bonding with the subsoil. Wetting or drying of the subgrade will be done as
necessary to assist in gaining beneficial results. Finally, the vegetative soil shall be placed in a minimum
12" loose lift. Vegetative soil will not be placed when the subgrade is frozen in other such condition that
would be detrimental to proper grading and planting.
3.7 Grading
Rough grading will be performed to establish a base for fill materials so that it can be adequately placed.
Uneven areas and low places will be graded to ensure proper contours and site drainage. Uniform finish
grading will transition excavated and disturbed areas into existing undisturbed areas to eliminate
ponding, erosion and washouts. Due to the change in scope of the project, exact finish grades and
contours will be determined in the field and approved by ARCADIS. Earth Tech and ARCADIS will
work together to design the best contours and grades for site performance and maintenance.
Nevertheless, the grades will be within 0.2 tenths of a foot below to 0.5 tenths of a foot above for the
grades determined in the field. Earth Tech will provide field control to determine layer thickness and
proper contours.
4.0 CONCLUSION
The proposed methods of construction outlined in this Plan are general procedures that Earth Tech will
follow in our execution of the work. Adjustments and adaptations invariably will be required as exact
field conditions dictate. A North Carolina licensed surveyor will establish site control and certify that all
soil material has been placed to proper lines, grades and elevations as determined in the field. The final
lines, grades, and elevation have to be determined in the field due to the change in the project scope of
work. Nevertheless, Earth Tech will follow the intent of the Contract Documents and work as directed
by ARCAD!S to implement the remedy.
ARCA DJS/ JFD Work Procedures IC:VFD ELECTR\SUBMJITALS\02200\WORKPROCEDURESJFDFINAL.DOC I July 17, 2000 5