HomeMy WebLinkAboutCORRESPONDENCE - PURCHASE ORDER - 9190954April 30, 2019
Ms. Bonnie Pierce, Ph.D.
Senior Specialist, Scientist
Environmental Regulatory Affairs
City of Fort Collins
bpierce@fcgov.com
970-416-4255
Subject: Proposal to Characterize Contaminants of Concern at Larimer County Landfill
Boundary and Off-Site and Assessment of Corrective Measures for the City of
Fort Collins, Colorado
Dear Ms. Pierce:
AECOM appreciates the opportunity to provide the City of Fort Collins with our proposal to
characterize the contaminants of concern at the Larimer County Landfill boundary and off-site and to
provide an Assessment of Corrective Measures. Our proposal has been prepared in response to the
request for bid issued by the City of Fort Collins on April 11, 2019.
AECOM is currently working on several long-term projects with other clients covering similar scopes of
work providing hydrogeologic input and management of the groundwater monitoring programs and
data evaluation in support of the requirements for the State of Colorado Solid Waste Regulations. The
scope presented in the following proposal and the project team selected for this work draws from our
experience on similar projects.
AECOM has an established working relationship with the City and have been successfully supporting
the City for the past four years through environmental assessment and air quality projects. We can
provide local support for this project through our Fort Collins office. Based on our local and regional
staff capabilities we are qualified to support each of the technical areas identified in the Scope of
Work.
We look forward to working with you and appreciate this opportunity to provide environmental services
to the City of Fort Collins. Please contact Vasanta Kalluri at (303) 228-3058 with any questions.
Yours sincerely,
AECOM Technical Services, Inc.
Vasanta Kalluri
Environmental Engineer/ Project Manager
Margaret Zebley, P.E.
Remediation Department Manager
Environment Business Unit
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Proposal for Environmental
Characterization and
Assessment of Corrective
Measures for the Larimer
County Landfill,
City of Fort Collins,
Colorado
April 30, 2019
City of Fort Collins Proposal i
This document includes proprietary data that shall not be duplicated, used or disclosed outside Simon for any purpose other than to evaluate this
document. This restriction does not limit Simon’s right to use information contained in this document if it is obtained from another source without
restriction.
Table of Contents
Project Background ............................................................................................................................... 1
Project Understanding ........................................................................................................................... 1
AECOM’s Relevant Experience ............................................................................................................. 2
Project Example No. 1 – Platte River Power Authority, Rawhide Facility............................................. 2
Project Example No. 2 – XCEL Energy, Various Power Stations in Colorado ..................................... 2
Project Example No. 3 – Colorado Springs Utilities, Clear Spring Ranch ............................................ 3
Project Example No. 4 – Garfield County Landfill, Garfield County, Colorado ..................................... 3
Project Team ........................................................................................................................................ 3
Technical Approach .............................................................................................................................. 5
Task 1.0 – Hydrogeologic Evaluation and Characterization of Contaminants of Concern at Landfill
Boundary and Off-Site ....................................................................................................................... 6
Task 2.0 – Assessment of Corrective Measures (ACM) ...................................................................... 7
Schedule............................................................................................................................................... 8
Project Budget ...................................................................................................................................... 8
Additional Assumptions ......................................................................................................................... 9
Limitations ............................................................................................................................................ 9
References ........................................................................................................................................... 9
City of Fort Collins Proposal 1
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Project Background
This project background and the scope of work presented in this proposal are based on the documents
provided to AECOM with the request for bid issued by the City of Fort Collins on April 11, 2019.
Larimer County has been operating the Larimer County Landfill (Landfill) since 1995 to monitor impacts
in surface water and groundwater related to disposal activities at the facility. Monitoring at the Landfill
has been completed in accordance with the United States Environmental Protection Agency (USEPA)
and Colorado Department of Public Health and the Environment (CDPHE) regulations including the
Federal Criteria for Municipal Solid Waste Landfills (40 Code of Federal Regulations [CFR] 258) and the
State Regulations Pertaining to Solid Waste Sites and Facilities (6 Code of Colorado Regulations [CCR]
1007-2).
The Landfill is a municipal solid waste (MSW) landfill that has been in operation since 1963 located
southwest of Fort Collins, Colorado. The Landfill has a footprint of 180 acres and is situated in the north
half of a 650 acre site. The southern half of the site serves as a borrow area for cover soil. The Landfill
does not have a bottom liner or leachate collection system and finished areas are covered with a
compacted-clay cap. Approximately forty percent of the landfill area is now covered with the remaining
area to be closed in phases as filling progresses.
Project Understanding
Our understanding of the project objective is to characterize contaminants of concern at both the landfill
boundary and offsite; and to complete an Assessment of Corrective Measures (ACM) to address
impacts to groundwater. Since 1965, the approved corrective action process, agreed between CDPHE
and Larimer County for has been monitored natural attenuation (MNA). However, due to the complex
hydrogeologic and geologic conditions, in a letter dated September 15, 2016, CDPHE requested a re-
evaluation of the site hydrogeologic assessment for identifying possible data gaps and to improve the
understanding of the effectiveness of the current groundwater monitoring network and potential data
gaps. Larimer County’s contractor (Trihydro Corporation [Trihydro]) submitted a Groundwater Monitoring
Network Evaluation and Site Investigation Work Plan in response to CDPHE’s request which was
approved on July 17, 2017. Trihydro completed site assessment activities in accordance with the Work
Plan. Conclusions related to the CDPHE September 15, 2016 comments included:
· The vertical and horizontal extent of vinyl chloride was delineated.
· The vertical and horizontal chlorinated volatile organic compounds (CVOCs) plume was
delineated in the Northern Aquifer indicating monitored natural attenuation (MNA) is likely
occurring.
· The 1,4-dioxane plum extends slightly further than the CVOC plume and has not been fully
delineated in the Northern Aquifer. The 1,4-dioxane plume in the Southern Aquifer appears to be
discharging into Smith Creek as it was detected in a surface water sample collected. Further
delineation of 1,4-dioxane is needed.
· Regional agricultural practice likely has contributed to elevated calcium, magnesium, sodium, and
sulfate concentrations. It is unclear how much landfill leachate or agricultural practices are
contributing to the calcium and magnesium concentrations.
· Alternative source demonstrations for sulfate and nitrate are on-going and will be further evaluated
by Trihydro following additional sampling.
Based on these conclusions, on April 11, 2019, the City of Fort Collins requested a proposal to
characterize the contaminants of concern at the Larimer County Landfill boundary and off-site on City
property and to provide an Assessment of Corrective Measures. AECOM proposes conducting the
scope of work through the following tasks:
City of Fort Collins Proposal 2
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· Task 1.0 – Evaluate available monitoring data from 1984 to present from the North and South
Aquifers with focus on the landfill boundary and offsite contamination that potentially impacts the
City property and prepare a Hydrogeologic Evaluation Report. The Report will include determining
the nature and extent of contamination, developing iso-concentration plots to show contaminant
distribution, and evaluating contaminant fate and transport to develop a preliminary site
conceptual model.
· Task 2.0 – Complete an Assessment of Corrective Measurements (ACM) analyzing the
effectiveness of at least three potential corrective measures for meeting the requirements and
objectives of the remedy as described under 40 CFR 258.57 and to evaluate if interim measures
are required prior to remedy selection to minimize environmental contamination, control or
mitigate off site migration, if necessary, promote effective remediation, and prevent the public’s
exposure to contaminants of concern.
We will work collaboratively with the City of Fort Collins in performing our hydrogeologic evaluation and
subsequent reporting. On completion of Task 1.0, we will prepare an ACM with the City of Fort Collins’
input to address offsite groundwater contamination. This ACM will be completed in accordance with the
applicable Federal and State regulations.
AECOM’s Relevant Experience
AECOM has considerable and ongoing experience with projects similar to those described in the City of
Fort Collins’ scope of work. Below we have provided brief project summaries of four ongoing projects
located within the State of Colorado that are aligned with components requested by the City of Fort
Collins.
Project Example No. 1 – Platte River Power Authority, Rawhide Facility
AECOM is supporting Platte River Power Authority (PRPA) in adherence to the State of Colorado
and Federal regulations including the State of Colorado Solid Waste Section 6 and Section 9,
Appendix B regulations and in the parallel work for the responses to the USEPA Coal Combustion
Residuals regulations. The regulated units include the ash landfill, ash ponds, and phosphorous
removal system ponds. We are providing ongoing expertise and support in the completion of
hydrogeologic assessments, developing compliant groundwater monitoring networks, performing
groundwater monitoring, and completing statistical evaluations. These differing technical streams
are conducted to maintain compliance with requirements of the applicable regulatory programs, and
to develop strategy and paths forward for understanding of site characteristics and to address
identified issues. For example, evaluation of geologic, hydrologic, and facility management practices
has been used to develop alternate source demonstrations to determine whether specific chemicals
present in the groundwater may be sourced from underlying Pierre Shale bedrock or due to
operational practices, or both. Our work is being completed collaboratively with PRPA with the intent
of developing, performing, and evaluating compliant monitoring programs, and, as necessary,
developing the appropriate assessment monitoring and corrective measures when statistically
significant increases (SSI’s) are identified. Our work has included participation in multiple meetings
and discussions with CDPHE to resolve potential issues, and with PRPA in the development of a
longer-term strategy for management of regulated units.
Project Example No. 2 – XCEL Energy, Various Power Stations in Colorado
AECOM manages the groundwater assessment program for XCEL Energy at seven power stations
under the State of Colorado, Solid Waste Section 6 and Section 9 regulations. The units include
existing and closed landfills and various impoundments. This is a 5-year program, and our role is to
conduct the semi-annual or annual groundwater sampling and analytical programs, prepare reports
in accordance with the schedule required by CDPHE, and to complete ongoing analysis of the
analytical data including understanding potential influences to SSIs from hydrogeologic conditions
not related to power station operations. We are also conducting and documenting semi-annual
City of Fort Collins Proposal 3
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landfill inspections at one of the facilities. The project objective is to maintain compliance for XCEL
with the established groundwater monitoring programs that have been approved by CDPHE for
each facility.
Project Example No. 3 – Colorado Springs Utilities, Clear Spring Ranch
AECOM performed a detailed comparison of the State of Colorado and Coal Combustion Residuals
regulations to develop a long-term strategy to manage the regulated units under the USEPA Coal
Combustion Residuals regulations. Specifically, for the Landfill regulated through the State of
Colorado and Coal Combustion Residual regulations we have performed a hydrogeologic
assessment of the area based on data from an extensive monitoring well network. From this
hydrogeologic assessment, we have developed a site-specific groundwater monitoring program to
meet the Coal Combustion Residual regulations requirements. Similar to the hydrogeologic regime
at Larimer County Landfill, this site has a complex physical, geologic and hydrogeologic regime,
with micro influences such that the groundwater characteristics can be subtly different even in
adjacent groundwater monitoring wells.
Project Example No. 4 – Garfield County Landfill, Garfield County, Colorado
In collaboration with our teaming partner, NWCC Consultants, we have provided ongoing support to
Garfield County Landfill on compliance, environmental, operational, and strategic planning for eight
years. Our ongoing support includes completing an evaluation of soil, groundwater and soil gas data
to better understand not only landfill gas, but also the presence of naturally occurring gases since
the Landfill is located within an actively producing natural gas field. Our understanding of the
hydrogeologic regime allowed us to develop and implement an efficient landfill gas monitoring
system.
Our work has included preparation of a Strategic Solid Waste Management Plan that has been used
to guide identification of strategic opportunities, marketing, operational, and management decisions
for the Landfill. This work has helped to create a financially strong and efficient model for running
the Landfill. One of the strategic opportunities AEOM identified included an innovative treatment
system for petroleum contaminated soils that would help reduce costs as treated soil can be used
as the daily soil cover, which otherwise would have to be purchased. AECOM designed and
implemented this innovative treatment system. We led meetings with the Air Pollution Control
Division (APCD) of CDPHE to work through permitting requirements as this process did not fit into
the typical processes that fall under APCD’s jurisdiction. This high profile project has received
significant local attention and below is a link to a local TV station broadcast featuring the Garfield
County Landfill:
http://www.westernslopenow.com/news/local-news/landfill-gets-new-eco-friendly-system
Additionally, we have prepared numerous air permits for the Garfield County Landfill, including the
Title V air permit. Our involvement included leading negotiations with CDPHE and developing and
an assessment and monitoring program.
Additionally, AECOM’s Colorado team has prepared ACM documents for United States Air Force bases,
Army Corps of Engineers, oil companies, and various States and municipalities across the United
States. The regulatory programs under which these ACMs have been prepared are similarly varied,
from CERCLA programs to State-regulated programs.
Project Team
Given the complexity of the project scope and the interlocking technical areas between the two principal
tasks, we chose a small technical team of experienced senior technical staff to provide project
leadership. They will be supported by mid-level and junior staff, as appropriate. Our project team has
City of Fort Collins Proposal 4
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been built with the personnel supporting the projects summarized in the previous section or other similar
projects. Therefore, we are not only providing our active experience, but also an institutional
understanding of how CDPHE views compliance and response to the applicable Solid Waste
regulations. Our organization chart identifying the key project personnel is shown below. We are
confident that the AECOM team assembled for this project has the necessary expertise to efficiently
fulfill the project objectives and be fully supportive of City of Fort Collins.
We will utilize personnel from both our Fort Collins and Greenwood Village offices to meet the project
schedule and technical requirements. With the project manager and other project staff located in Fort
Collins, AECOM will provide expedited and cost-efficient
services for in-person collaboration meetings that this project
could require.
Below are brief biographies for the project team, highlighting the
key attributes and experience each person brings that are
specific to the needs for this project. We would be pleased to
provide resumes for our project team personnel if requested by
the City of Fort Collins. Our task lead personnel will manage
each task, and to help control project costs we will utilize more
junior personnel wherever appropriate.
Ms. Vasanta Kalluri, PE, Project Manager
Vasanta Kalluri based in our Fort Collins office will serve as the project manager. She has almost 20
years of experience managing and providing technical support on environmental investigation and
remediation projects. She is a professional engineer (Wisconsin, Minnesota, and Colorado PE in
progress) and has worked on similar solid waste landfill evaluation projects in Wisconsin and Ohio. Ms.
Kalluri has experience with data evaluation, statistical trend analysis, fate and transport analysis,
assessment of corrective measures, remediation design and implementation. She will work with the
technical leads for this project to deliver quality products, on time and within budget. Ms. Kalluri will
participate in project meetings with the City of Fort Collins and other stake holders and will be the
primary contact for the City of Fort Collins’ project manager.
Along with the project team listed
below, Ms. Margaret Zebley will
continue her role as the overall
Program Manager and an alternate
line of communication for the City
of Fort Collins, as presented in our
8631 General Environmental
Services Proposal (January 2018).
City of Fort Collins Proposal 5
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Mr. Geoffrey Webb, Principal
Geoff Webb will serve as Principal-in-Charge, acting as a senior resource throughout the project. Geoff
brings 40 years of diverse professional experience including work with various utility companies on
environmental and remediation projects and is the project manager of our illustrated projects for the
Platte River Power Authority, Colorado Springs Utilities, and Garfield County. He has managed
numerous multidisciplinary projects, including many that involved working within regulatory requirements
of RCRA, CERCLA, and CDPHE. Currently, he is part of the AECOM National Practice initiative for our
Coal Combustion Residual projects, and on projects within Colorado, he is involved in developing
project strategies for sites where both the Coal Combustion Residual rules and CDPHE Solid Waste
regulations are applicable.
Ms. Katherine Nicholas, PG, Hydrogeological Evaluation Lead
Task 1 will be led by Katherine Nicholas, PG (WY), a qualified groundwater scientist as defined in 6
CCR 1007-2, Section 1. Ms. Nicholas is a Senior Geologist with 12 years of experience working on
groundwater-related projects. Ms. Nicholas currently serves as project manager for the Colorado
Springs Utilities projects and works collaboratively with Colorado Springs Utilities and CDPHE to
develop a path forward to determine hydrogeologic conditions at an alum sludge pond in Colorado
Springs. Ms. Nicholas has also worked with municipalities including Campbell County and Sheridan
County on similar projects under the regulation by the Wyoming Department of Environmental Quality
(WDEQ). Katherine worked collaboratively with Campbell County and WDEQ to develop hydrogeologic
evaluations and providing an evaluation of data and hydrogeologic conditions for Campbell County
Landfills No. 1 and No. 2 in Gillette, Wyoming. Ms. Nicholas has previously served as project manager,
task manager, or field lead for large multi-faceted field sampling programs.
Ms. Naseem Hasan, PE, Assessment of Corrective Measures Lead
Task 2 will be led by Naseem Hasan. Ms. Hasan is a licensed Professional Engineer (CO) and chemical
engineer with over 30 years of experience in environmental engineering. Ms. Hasan has extensive
experience developing ACMs for CVOC and 1,4 dioxane in Colorado and other states and is a member
of the ITRC 1,4-dioxane team. Her expertise is soil and groundwater remediation including corrective
measure/feasibility studies, treatability studies, remedy assessment, cost estimation and site closure.
Ms. Hasan has decades of experience in evaluating treatment technologies and formulating corrective
measure alternatives to support remedy selection for RCRA, CERCLA and other sites. As part of
comparative analysis of corrective measure assessment, Ms. Hasan analyzes potential impacts of
corrective measure alternatives, considering cross-media impacts and sustainability, implementation
timeframe, cost-effectiveness and other related factors. She has developed remedial strategies
combining source control, containment or active treatment. She is currently leading the corrective
measure assessment of groundwater contamination at the Platte River Power Authority site in Colorado.
Ms. Hasan is knowledgeable of federal and state regulatory requirements pertaining to corrective action
requirements for landfills.
Technical Approach
The focus of our technical approach is to evaluate the existing hydrogeological and analytical data to
develop a preliminary site conceptual model and prepare an ACM that will assist the City of Fort Collins
in determining the path forward. AECOM will use its experience in and knowledge of applicable Federal
and State of Colorado Solid Waste Regulations to perform these evaluations in the following two
phases:
· Task 1.0 – Hydrogeologic Evaluation and Characterization of COCs
· Task 2.0 – Assessment of Corrective Measures
Based on our preliminary evaluation of the documentation provided by the City of Fort Collins, the
following significant hydrogeologic features have been identified:
City of Fort Collins Proposal 6
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· Smith Creek, which originally flowed through the middle of the landfill and was diverted into Fossil
Creek. A portion of Smith Creek was then filled with MSW and a slurry wall was installed to divert
subsurface water flow.
· The former location of Fossil Creek, which was interfering with landfill operations and thus
diverted into a channel. The former Fossil Creek was then filled with MSW.
· The bedrock divide and subsurface lithology beneath the landfill, including hydrogeologic
conditions and groundwater chemistry.
Evaluation of these hydrogeological features will be key in developing a site conceptual model and
identifying data gaps.
Task 1.0 – Hydrogeologic Evaluation and Characterization of Contaminants of
Concern at Landfill Boundary and Off-Site
The hydrogeologic and geochemical conditions at Larimer County Landfill are complex as the western
and upgradient portion of the site is in a different geologic formation and the site is separated by a
west-east trending bedrock divide of competent shale. The eastern two-thirds of the site is underlain
by the Pierre Shale formation, whereas the Niobrara formation results in geologic outcrops along the
west. The bedrock divide separates the shallow groundwater into two aquifers herein referred to as the
North Aquifer and South Aquifer.
In the Trihydro Site Characterization Report (2018) completed on behalf of Larimer County Landfill,
Trihydro indicated that the 1,4-dioxane plume has not been fully delineated in the Northern Aquifer
and the 1,4-dioxane plume in the Southern Aquifer appears to be discharging in Smith Creek as of
April 2018 (Trihydro, 2018). Trihydro evaluated alternate sources of sulfate, magnesium, sodium, and
cadmium and indicated that regional agricultural practices likely contributed to some of the calcium,
magnesium, sodium, and sulfate concentrations. However, they further indicated that leachate
generally reduces and immobilizes sulfate, but liberates calcium and magnesium so it is unclear how
much landfill leachate or agricultural practices are contributing to the calcium and magnesium
concentrations (Trihydro 2018). Triyhydro (2018) also indicated a Corrective Measures Assessment
and Alternative Source Demonstration Studies are ongoing for sulfate and nitrate.
AECOM will review available data and relevant documentation to make an initial assessment of
hydrogeologic conditions and groundwater chemistry in accordance with applicable Federal and State
regulations, including State of Colorado Solid Waste Section 6 and Section 9, Appendix B regulations.
The scope of work under Task 1.0 will include:
· Gathering and compilation of available, relevant data collected since 1984 to prepare a data
summary. AECOM will compile data provided by the City of Fort Collins into summary tables, as
appropriate. Although excel spreadsheets or
database exports are preferred, AECOM can compile
data from PDF versions of data tables. If data are
provided by the City of Fort Collins in an electronic
format, AECOM will upload the information into a
database. Otherwise, AECOM will compile summary
tables, as appropriate.
· Evaluation of available site groundwater data and
historic geologic and groundwater monitoring reports
to understand the conditions in the North and South
areas of the Landfill. Data will be evaluated relative to
appropriate regulatory limits. We will also evaluate
data quality and will identify significant data gaps.
· Evaluation of existing well construction and soil boring
log details, as available, to further understand the
varying geologic and hydrogeologic conditions
The contaminant fate and transport
analysis presented in this proposal is a
2-dimensional analysis. However, if
warranted, AECOM has the capability
to perform complex 2- dimensional
and 3-dimensional contaminant
transport modeling and can provide a
separate cost estimate upon request.
Additionally, AECOM can perform a
City of Fort Collins Proposal 7
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present at the site. This information will be included in the preparation of lithological cross sections
with potentiometric surface and COCs – CVOCs and 1,4-dioxane data. Water table data,
potentiometric data, and hydraulic conductivity information (as available) will also be evaluated to
understand flow pathways and interaction with surface water.
· Evaluation of potential other data, including publicly available literature sources (e.g., USGS)
concerning the geology and hydrogeology of the area, well records available from the Colorado
Division of Water Resources, records of monitoring wells installed at the facility, geotechnical
reports prepared, as applicable, in support of facility construction, and landfill design and
construction records and documentation, as available.
· Preparation of iso-concentration plots to illustrate the distribution of COCs. These plots will be
used to evaluate the nature and extent of COCs. Additionally, aquifer geochemistry will be
evaluated to understand its influence on contaminant transformation and migration. Based on this
information, AECOM will perform a 2-dimensional fate and transport analysis of the COCs in
groundwater.
· Statistical trend analysis of the analytical data with emphasis on the significance of changes in
water quality over time in offsite monitoring wells and surface water.
· Developing a preliminary site conceptual model based on the above-mentioned evaluations and
identifying key data gaps associated with understanding contaminant sources and pathway.
· Preparation of a Hydrogeologic Evaluation Report summarizing the results of the existing data
evaluation, data gap analysis, fate and transport evaluation, and a preliminary site conceptual
model with supporting figures and tables.
AECOM will provide an electronic draft copy of the report for review and comment by the City of Fort
Collins. We will incorporate review comments and submit a final version of the report in a PDF format for
the City of Fort Collins’ records and submittal to CDPHE. Our costs (Table 1) include one meeting with
City personnel to discuss the results of completion of Task 1.0 and to discuss the draft Report findings
prior to finalizing.
Task 2.0 – Assessment of Corrective Measures (ACM)
In conjunction with the activities described above, AECOM will complete an ACM. This assessment
will include data review and professional evaluation of effectiveness of at least three corrective
measures to meet the requirements and objectives of the remedy as described under 40 CRF 258.57.
The development and evaluation of the corrective measures will also follow state guidance as
specified in the Corrective Action Guidance document (CDPHE Hazardous Materials and Waste
management Division, May 2002). The assessment will be
documented in an ACM report that will include
recommendations for improvements, changes, or additional
corrective measures required to address contamination
migrating offsite.
The ACM report will include analysis of the effectiveness of
at least three potential corrective measures to meet the
requirements and objectives of the remedy as described
under 40 CFR 258.57 through addressing the following topics:
· The performance, reliability, ease of implementation, and potential impacts of appropriate potential
remedies including safety impacts, cross-media impacts, source and boundary control to prevent
further releases, and control of exposure to residual contamination.
· Time expected for the corrective measure to be effective.
· Cost of remedy implementation and maintenance.
AECOM has the expertise to
support the City of Fort Collins’
Sustainability Goals by including
green remediation and sustainability
in our ACM alternatives evaluation
criteria, if requested.
City of Fort Collins Proposal 8
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· State or local permits or other institutional requirements that may affect implementation of the
remedy.
The ACM will include an evaluation to determine if interim measures are required for regulatory
compliance prior to remedy selection to minimize environmental contamination, promote effective
remediation, and prevent the public’s exposure to COCs. Interim measures should be consistent with
the remedy objectives and consider the following factors:
· Time required to implement the final remedy
· Actual or potential exposures of nearby populations, environmental receptors, and visitors to the
impacted City Natural Area
· Weather conditions that may cause hazardous constituents to migrate or be released
We will prepare the Assessment of Corrective Measures Report (ACM Report) presenting the analysis
and recommendations for remedy selection that considers both short-term and long-term remedy
effectiveness and protectiveness for potential human and environmental receptor exposure. AECOM will
provide an electronic draft copy of the report for review and comment by the City of Fort Collins. We will
incorporate review comments and submit a final version of the report in a PDF format for the City of Fort
Collins’ records and submittal to CDPHE. Our costs (Table 1) include one meeting with the City of Fort
Collins to discuss the draft Assessment of Corrective Measures report.
Schedule
AECOM is able to commence work upon receipt of written approval of this proposal by the City of Fort
Collins. The schedule for completion of Tasks 1.0 and 2.0 will be dictated by the State-issued
Consent Decree. However, for the City of Fort Collins’ planning purposes, we are providing the
following preliminary schedule:
· Notice-to-proceed by the City of Fort Collins (May 20, 2019)
· Initiate Task 1.0 as the first stage and prepare a draft Hydrogeologic Evaluation Report (May 20 –
July 19, 2019)
· City of Fort Collins review and approval of the Hydrogeologic Evaluation Report (July 19, 2019 –
August 2, 2019)
· Initiate the ACM Report following agreement and approval of the Hydrogeologic Evaluation Report
by the City of Fort Collins (August 2 – September 27, 2019)
· City of Fort Collins review and approval of the ACM Report (September 27 – October 11, 2019)
We estimate that the total project duration will be five months.
Project Budget
Our estimate of cost to complete the work described in the above proposal is $35,000. Work will be
performed on a Time and Material basis under the Professional Services Agreement, Work Order
between AECOM Technical Services, Inc. and the City of Fort Collins, Colorado effective March 29,
2018 and extended on February 28,2019 through February 27, 2020.
The following Table 1 summarizes the estimated task costs for this proposal.
City of Fort Collins Proposal 9
Use or disclosure of data contained on this sheet is subject to the restriction on the first page of this document.
Table 1 – City of Fort Collins, Characterization of Contaminants of Concern at Larimer County
Landfill Boundary and Off-Site and Assessment of Corrective Measures
Task Description Labor Other Direct
Costs Subtotal
Task 1 Hydrogeologic Evaluation and
Characterization of COCs at
Landfill Boundary and Off-Site
$18,124 $0 $18,124
Task 2 Preparation of ACM Report $16,876 $0 $16,876
Total $35,000
Additional Assumptions
In addition to the assumptions included in the task descriptions, AECOM considered the following to
develop our cost estimate:
· We have included two project meetings to be held between the City of Fort Collins, CDPHE, and
AECOM. The scheduling and scope of these meetings will be to discuss the findings from the
draft hydrogeologic evaluation report and the draft ACM report.
· We have not included responding to CDPHE or Larimer County comments to these reports in our
cost estimate.
Limitations
The proposed scope of work proposed herein will be limited to a review of readily available and relevant
information and information provided by the client, its agent, and regulatory agencies. Services
performed by AECOM will be conducted in a manner consistent with the level of care and skill ordinarily
exercised by members of the same profession currently practicing in the same locality under similar
conditions. AECOM will not independently verify information provided by others. No expressed or
implied representation or warranty is included or intended in our reports, except that our services were
performed, within the limits prescribed by our client, with the customary thoroughness and competence
of our profession. Therefore, AECOM will assume no liability for any loss resulting from errors or
omissions arising from the use of inaccurate/incomplete information or misrepresentations made by
others.
References
Trihydro. 2018. Site Assessment and Characterization report, Larimer County Landfill, 5887 South Taft
Hill Road, Fort Collins, Colorado. July 13, 2018.
site-specific human health and/or
ecological risk assessment to develop
site-specific exposure criteria. We can
provide a separate scope and cost
estimate if environmental risk
assessment is appropriate for this
project.