HomeMy WebLinkAboutTerracon - Supp Agmnt to Cont. No. 1015 - 5.17.2021 Irerracon
April 15, 2021
City of Waterloo
715 Mulberry Street
Waterloo, Iowa 50703
Attn: Mr. Matt Schindel
P: (319) 291-4312
E: Matt.SchindelQWaterloo-la.org
Re: Proposal for Over Excavation Activities
City ROW
300 Jefferson Street, Waterloo, Iowa
Registration No. 20200033 LUST No. 9LTS91
Terracon Project No. 13207110
Dear Mr. Schindel:
Terracon Consultants, Inc. (Terracon)appreciates the opportunity to submit this proposal to assist
with over excavation activities at the above referenced site. Terracon has conducted thousands
of environmental service projects across the country including the State of Iowa. In addition,
Terracon has extensive experience performing geotechnical and construction testing services.
For more detailed information on all of Terracon's services please visit our web site at
www.terracon.com. An outline of the project, Terracon's scope of services, including schedule
and compensation are provided in the following sections
1.0 PROJECT INFORMATION
The Iowa Department of Natural Resources (IDNR) has required a bedrock assessment of the
site due to the shallow bedrock and elevated soil concentrations reported during the 2020 UST
Closure Report. To comply with IDNR guidance, Terracon completed a Soil Delineation
Assessment of the source area in March 2021. The findings of the Soil Delineation Assessment
indicated soil impacts are generally localized to the area of B-1/SS-1. In correspondence dated
April 2, 2021, the IDNR accepted Terracon's Soil Delineation Report and recommendation to
complete a targeted over excavation of the soil source prior to completing the Tier 2 Report.
As stated above, the proposed excavation will be focused on B-1/SS-1. Terracon anticipates the
excavation with likely extend no more than 10 to 15 feet from the source area and will likely extend
to a maximum depth of 8-feet below existing grade (bedrock surface). Based on the Soil
Delineation Assessment boring logs, Terracon anticipates the upper 5-feet of soils may be able
to be stockpiled on-site for use as backfill pending field observations. The volume of the proposed
Terracon Consultants Inc., 3105 Capital Way,Suite 5 Cedar Falls,IA 50613
P 319 277 4016 F 319 277 4320 terracon.com
Over Excavation Proposal Irerracon
City ROW Waterloo, Iowa
April 15, 2021 Terracon Project No. 13207110
excavation (depicted on Exhibit 1, attached) is estimated to be up to 65 cubic yards (CY), with up
to 35 CY to potentially remain on-site for use as backfill. The actual volumes will be dependent
on filed screening readings, final excavation boundaries, and Certified Groundwater Professional
(CGP) discretion.
Terracon has assumed that the City of Waterloo (the City) will provide equipment and personnel
necessary to perform the excavation activities and hauling of soil for disposal. Terracon also
assumes the City will provide traffic control and utility locates necessary to complete the
excavation activities. The City will also be responsible for removal and replacement of surface
paving and landscaping as well as the light pole located within the proposed excavation area.
Terracon's responsibilities will generally be confined to excavation oversight, field screening and
soil sampling, and reporting.
In preparation of this proposal, Terracon has contacted the Black Hawk County Landfill and
confirmed the landfill is willing to accept the contaminated soils without further characterization.
2.0 SCOPE OF SERVICES
Terracon has a 100% commitment to the safety of all its employees. As such, and in accordance
with our Incident and Injury Free®safety culture, Terracon will update our safety plan for use by
our personnel during field services. Prior to commencement of on-site activities, Terracon will hold
a meeting to review health and safety needs for this specific project. At this time, we anticipate
performing fieldwork in a United States Environmental Protection Agency (USEPA) Level D work
uniform consisting of hard hats, safety glasses, protective gloves, and steel-toed boots. It may
become necessary to upgrade this level of protection, at additional cost, during sampling activities
in the event that petroleum or chemical constituents are encountered in soils or groundwater that
present an increased risk for personal exposure.
The following scope of services presents Terracon's approach to completing the proposed over
excavation activities.
2.1 Over Excavation
The site-specific Health and Safety Plan will be updated prior to starting field work
and will be used by Terracon personnel.
The City will perform the excavation services as outlined. The City will request
municipal utility locations through Iowa One-Call for the excavation activities. The
City will also be responsible for the location of private utilities.
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Over Excavation Proposal Irerracon
City ROW Waterloo, Iowa
April 15, 2021 Terracon Project No. 13207110
The proposed excavation is an approximately 10 to 15-foot square area centered
on boring B-1 and tank closure sample location SS-1. It is anticipated the
excavation will extend to 8-feet below existing grade to the soil/bedrock interface.
Terracon anticipates the upper 5-feet of soils maybe able to be stockpiled on-site
for use as backfill. The volume of the proposed excavation is estimated to be up
to approximately 65 cubic yards (CY), with an estimated 35 CY to potentially
remain on-site for use as back fill. For the sake of this proposal, Terracon has
assumed one-day on-site to oversee excavation activities.
Terracon will field screen the soil during the excavation in accordance with the
requirements of Iowa Administrative Code (IAC) Chapter 135.12(11)c. Soil
samples will be screen for volatile organic vapors utilizing a photoionization
detector (PID) throughout the excavation activities. Field screening results will be
used to guide the excavation and determine the final extents along the with visual
and olfactory observations. Soil results collected during the Soil Delineation
Assessment will also be utilized for determine the final extents. Soil that is deemed
non-impacted by the CGP based on field screening readings will be stockpiled on-
site for later reuse as backfill.
When field screening indicates that sufficient soil removal has taken place as
determined by the CGP, final soil samples will be collected for laboratory analysis
per IAC Chapter 135.12(11)c. Soil samples will be collected for field screening
every 100 square-feet from the base and sidewalls of the excavation and soil
samples will be collected for laboratory analysis every 400 square-feet from the
base and sidewalls of the excavation at the location of highest PID reading. Based
on the anticipated size of the excavation, it is estimated up to 8 samples will be
collected for field screening and up to 4 samples will be submitted for laboratory
analysis. The final extents of the excavation will determine the actual screening
and laboratory sample numbers.
The excavation will generally extend to the proposed boundaries. If field screening
indicates impacts remain, the final boundaries may be extended further to remove
the impacted soil per the discretion of the CGP. In addition, the final boundaries
may not extend to the proposed boundaries if field screening readings indicate that
excavation can be stopped. The excavation depth will not extend beyond
approximately 8-feet in depth due to the presence of bedrock.
The excavation will be backfilled with mechanically compacted imported fill sand
to approximately 5-feet followed by replacement of the mechanically compacted
stockpiled soils. Compaction and associated testing, if necessary, will be
completed by the City
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Over Excavation Proposal Irerracon
City ROW Waterloo, Iowa
April 15, 2021 Terracon Project No. 13207110
The soil samples will be submitted to a certified lab under standard chain of
custody protocols for analysis of benzene, toluene, ethylbenzene, and xylenes
(BTEX) according to Iowa Method OA-1 and total extractable hydrocarbons (TEH)
according to Iowa Method OA-2. The IDNR has indicated that analysis of methyl
tert-butyl ether (MTBE) is not required in soils.
Terracon will prepare and submit an Excavation Report following completion of
excavation activities. The report will detail the results of the excavation activities
and include appropriate mapping, laboratory reports, photographic log, etc.
Following submittal of the Excavation Report and approval of the IDNR, Terracon
will proceed with completion of the Tier 2 Report scope.
2.2 Schedule
Services will be initiated upon receipt of the written notice to proceed and on a date mutually
agreeable between the City and Terracon. In order to comply with the proposed schedule, the
following items are required to be provided by the client at the time of notification to proceed in
order to meet the client's required project completion date. Please include the following requested
items along with the notification to proceed:
Right of entry to conduct the field services.
Notification of restrictions or special requirements (such as safety) regarding accessing
the site.
A signed Supplement to Agreement for Services (Agreement) evidencing acceptance of
this scope of services.
2.3 Scope and Report Limitations
The fees in Table 1 assume a single mobilization to the site and field work will be completed in
one day. Terracon has assumed the City will make necessary arrangements to complete
excavation activities including removal and repair/replacement of surface paving and
landscaping, utility locates, furnishing of excavation equipment and dump trucks, traffic control,
and importing and compaction of backfill material. Terracon has also assumed that excavated
material that is deemed unsuitable for reuse will be transported to the Blackhawk County Landfill
by the City. Landfill disposal fees will be the responsibility of the City. Terracon has confirmed
with the landfill that they are willing to accept excavated material as is and further characterization
is not required.
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Over Excavation Proposal Irerracon
City ROW Waterloo, Iowa
April 15, 2021 Terracon Project No. 13207110
The findings and conclusions presented in the final report will be based on the site's current utilization
and the information collected as discussed in this proposal. Please note that we do not warrant
database or third-party information or regulatory agency information used in the compilation of
reports.
This evaluation will make use of Iowa-specific risk-based corrective action (RBCA) protocols to
evaluate the nature of adverse environmental impact associated with the identified chemical
release under 1996 changes to Iowa Administrative Code 4558, Chapter 135. The evaluation
does not constitute a complete risk assessment consistent with the definitions and protocols of
CERCLA. The client should recognize that no guarantee can be made that the RBCA evaluation
will result in either a no action or reduced remedial recommendation.
The limitations herein must be considered when the user of this report formulates opinions as to
risks associated with the site. No warranties, express or implied, are intended or made.
3.0 COMPENSATION
Fees for services specific to this site are $5,325 and are detailed in the attached Table 1. Interim
invoices will be submitted regularly and are due upon receipt. Invoices will reflect the units
performed in accordance with the above discussion and expressed in Table 1. If, as a result of
these services, additional work is required outside the scope of this proposal, you will be
contacted, and upon request, proposed costs for additional work will be provided. Client
authorization will be obtained prior to commencement of additional work outside the scope of this
proposal.
4.0 AUTHORIZATION
This proposal may be accepted by executing the attached Supplement to Agreement for Services
and returning one copy to Terracon. Services will be initiated upon receipt of the written notice to
proceed.
The terms, conditions and limitations stated in the Agreement, and sections of this proposal
incorporated therein, shall constitute the exclusive terms and conditions and services to be
performed for this project. This proposal is valid only if authorized within 90 days from the
proposal date.
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Over Excavation Proposal Irerracon
City ROW Waterloo, Iowa
April 15, 2021 Terracon Project No. 13207110
We appreciate the opportunity to provide this proposal and look forward to working with the City
of Waterloo on this project. If you have questions or comments regarding this proposal, please
contact either of the undersigned.
Sincerely,
Terracon Consultants, Inc.
Daniel M. Green, CGP 4enior
e M. Nelson, REM, CGP
Project Geologist Scientist
Attachments: Exhibit 1
Table 1
Supplement to Agreement for Services
Copies: Addressee (email)
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Estimated extent of
proposed excavation
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DIAGRAM IS FOR GENERAL LOCATION ONLY,AND IS AERIAL PHOTOGRAPHY PROVIDED
NOT INTENDED FOR CONSTRUCTION PURPOSES BY MICROSOFT BING MAPS
Project Manager: Project 13207110
DC 13EXCAVATION DIAGRAM Exhibit Irerracon
Drawn by: Scale:
DMG ASSHOWN
Checked by: Jefferson Street ROW
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F�F� 3105 Capital Way,Ste s 300 Jefferson Street
Approved by: Date:March 2021 Cedar Falls,IA 50613.7030 Waterloo, IA
DMG
Table 1: Services and Fees
Terracon Project Number: 13207110
Site Name: City ROW
Address: 300 Jefferson Street
City,State: Waterloo, Iowa
LUST Number: 9LTS91
Registration Number: 202000033
Date: 4/15/2021 Merracon
Cost per
Task Unit Unit Type No.of Units Total
Engineering Services
Environmental Department Manager(project coordination,client communications)" $ 135 /hour 4 $ 540
Certified Groundwater Professional(scope development, project management)" $ 115 /hour 8 $ 920
Over Excavation Report $ 1,500 1 lump sum 1 1 1 $ 1,500
Subtotal $ 3,460
Field Services
Field personnel mobilization(Up to 50 miles) $ 315 1/mobilization 1 $ 315
Daily equipment charges(IP/water probe, PID,survey,etc.) $ 200 1 /day 1 1 $ 200
Field Geologist/Engineer/Scientist" $ 85 1 /hour 1 10 1 $ 850
Subtotal $ 1,365
Sample preparation and laboratory analysis:
Soil: OA-1 (BTEX)and OA-2(TEH) $ 100 1 /sample 1 5 1 $ 500
Subtotal $ 500
Total $ 5,325
Irerracon-
Reference
Number: 13217110
SUPPLEMENT TO AGREEMENT FOR SERVICES
CHANGE TO
SCOPE OF SERVICES AND FEES
This SUPPLEMENT to AGREEMENT FOR SERVICES to the original Agreement for Services(original Agreement dated 02/01/2021,Agreement
reference number P13207110)is between City of Waterloo IA("Client")and Terracon Consultants, Inc.("Consultant")for additional or changed Services to
be provided by Consultant for Client on the Project,as described in the Agreement for Services.This Supplement is incorporated into and part of the
Agreement for Services.
1. Scope of Services. The scope of the additional or changed Services are described in the Scope of Services section of the Consultant's
Supplemental Proposal, unless Services are otherwise described below or in Exhibit B to this Supplement (which section or exhibit are incorporated
into the Supplement).
See attached Terracon Proposal dated April 15,2021
2. Compensation. Client shall pay compensation for the additional or changed Services performed at the fees stated in the Supplemental Proposal
unless fees are otherwise stated below or in Exhibit C to this Supplement(which section or exhibit are incorporated into the Supplement).
See attached Terracon Proposal dated April 15,2021
All terms and conditions of the Agreement for Services shall continue in full force and effect. This Supplement is accepted and Consultant is
authorized to proceed.
Consultant: Terracon Consultants, Inc. Client: City of Waterloo IA
By: 1 Date: 4/15/2021 By: Qve i-k i H4 .r4 Date: 5/17/2021
Name/Title: Dave C.Cleary, REM /Environmental Name/Title: Mayor Quentin Hart/City of Waterloo
Department Manager
Address: 3105 Capital Way,Ste 5 Address: 715 Mulberry St
Cedar Falls, IA 50613-7030 Waterloo, IA 50703
Phone: (319) 277-4016 Fax: (319) 277-4320 Phone: (319) 291-4312 Fax: (319) 291-4262
Email: Dave.Cleary@terracon.com Email: Quentin.Hart@Waterloo-ia.org
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