HomeMy WebLinkAbout2024-766-E-Solid Waste-Draper Aden Associates-Orange County Regional Landfills Closed MSW Landfill Leachate PFAS Study – Phase 1
Task Order Request
TO: Mr. Robert Williams REVISED
Orange County Solid Waste
FROM: David Garrett, PG, PE
Senior Project Manager
DATE: December 6, 2024
SUBJECT: Orange County Regional Landfills
Closed MSW Landfill Leachate PFAS Study – Phase 1
Leachate Sampling and Analysis
Proposal for Survey & Engineering Services
TRC Proposal No. TBD
Estimated Fee = $28,550
2024 PN: 635043.9990
At your request, Draper Aden Associates/TRC Engineers, Inc. (TRC), is pleased to offer this proposal for
a Leachate PFAS Study at the closed MSWLF unit (South landfill), located at the Orange County Regional
Landfill Facility (Facility) on Eubanks Road in Chapel Hill, NC. This proposal outlines our understanding
of the project scope, tasks we will complete, assumptions underlying our proposal, and proposed fees.
PROJECT UNDERSTANDING: TRC understands the project will consist of sampling leachate at the
South landfill unit, for the purpose of complying with North Carolina Department of Environmental
Quality (NCDEQ) Solid Waste regulations. The regulations require sampling and reporting of per- and
poly-fluoroalkyl substances (PFAS) in leachate, surface water discharges and groundwater at all
permitted landfills. The Orange County Solid Waste Management Department (OCSWD) has requested
TRC to perform the leachate sampling and make recommendations on treatment options based on
the results. This proposal describes services to meet this request in three tasks.
Based on reviewed construction plans (ca. 2005), there are two leachate pumping stations at the South
landfill unit, one shared by Phases 1 and 2 (PS #1) and another shared by Phases 3 and 4 (PS #2). The
plans also show that PS #2 connects to PS #1 by a force main. Recent aerial photography shows a
landfill gas (LFG) plant near PS #1; condensate from the LFG plant drains into PS #1. The liquids are
pumped from PS #1 to a Publicly Owned Treatment Works (POTW) for wastewater treatment. Phases
1 and 2 contain the older waste placed in the South landfill, while Phases 3 and 4 contain younger
waste. Published research indicates that wastes of different ages can exhibit different PFAS compounds
and concentrations, hence treatment options may differ.
Docusign Envelope ID: 911DA9D6-C358-4231-B7E3-0443B926487C
Mr. Robert Williams
December 6, 2024 – Closed MSW Landfill Leachate PFAS Study – Phase 1
Page 2 of 5
The wet well for PS #1 was “dry” for both 2023 and the Spring 2024 sampling events, but leachate was
present in PS #1 during the Fall 2024 sampling event, conducted in mid-November. TRC had initially
prepared a contingency plan to find alternative access points for sampling the leachate, but it appears
the leachate may be sampled in a conventional manner from one or both sumps. TRC recommends
we examine the Landfill Gas (LFG) production records, in pursuit of a better understanding of the causes
for the leachate sump going dry. TRC also recommends performing a visual inspection of the landfill
cover to detect potential maintenance needs.
SCOPE OF SERVICES
Task 1 - Site Visit and Records Review: TRC engineers and a sampling technician will visit the landfill
with Facility staff to confirm that we can sample leachate at one or both pump stations and inspect the
landfill cover for regulatory compliance, e.g., healthy vegetation, no erosion or obvious settling. We
will request records for the leachate system and LFG production. TRC will prepare a list of field and
laboratory analytes to detect whether PFAS compounds are present in the leachate, and if so, what
chemical compounds and other characteristics are present that would affect treatability.
Task 2 - PFAS Sampling Event: TRC’s experienced staff will conduct the leachate sampling and test key
field parameters using specialized PFAS sampling protocols at one or both pump stations. TRC will
deliver the samples to subcontractor Pace Analytical in Raleigh, NC (Pace), which will analyze the
samples under strict chain-of-custody protocols. Pace will analyze the samples for PFAS using EPA
Method 1633f with other constituents specified by NCDEQ and basic water chemistry.
Task 3 - Reporting and Project Management: TRC will provide the Facility with a draft summary report
for the sampling event. TRC will treat the data as confidential and review our findings with Facility
management, prior to issuing any final reports. The report will describe in brief whether PFAS are
present in the South Landfill leachate; if so, what specific PFAS compounds are present, and what other
constituents are present that might affect treatability. This report will not be a full treatability study,
whereas more data may be required. Please keep in mind the POTW will be facing similar concerns
over the discharge of PFAS, and it makes sense for these entities to cooperate – this itself will drive
some of the treatment effort needed by the landfill. This study will be left for a future Phase 2.
Our report will provide an opinion on which of the many available technologies OCSWD may wish to
evaluate further, pursuant to a full treatability study or a “proof of concept” field demonstration. We
will provide Orange County with an opinion on order-of-magnitude treatment costs, based on what is
known at the time. The content of this report can be better defined once the sampling data is in hand.
TRC will make a brief statement concerning landfill cover maintenance issues, based on our
observations. After reviewing the findings with OCSWD, TRC will finalize the report for your records
and prepare the sampling data only for submittal to NCDEQ – only what is required. Other findings
and preliminary recommendations are not required to be submitted.
Docusign Envelope ID: 911DA9D6-C358-4231-B7E3-0443B926487C
Mr. Robert Williams
December 6, 2024 – Closed MSW Landfill Leachate PFAS Study – Phase 1
Page 3 of 5
SCHEDULE: The following schedule is contingent on when TRC receives the authorization, weather
conditions, and end-of-year scheduling concerns. TRC plans to initiate the site visit and records review
within two weeks of receiving authorization from OCSWD. TRC anticipates completion of this phase of
work within three weeks of commencement. TRC anticipates the fieldwork will start within one to two
weeks of completing our records review, likely during the first quarter of 2025.
TRC expects to complete the field inspection and leachate sampling in one working day, assuming at
least one of the pump stations exhibits leachate on the day of sampling. The sampling could be delayed
if both pump stations are dry. TRC anticipates the laboratory analyses to take 4 to 6 weeks after the
sampling date. TRC will prepare the draft report within four weeks of receipt of the laboratory reports
and finalize the report within one week of receipt of Orange County comments.
FEES: TRC will invoice Orange County monthly on a time and materials basis, with the following
recommended not-to-exceed costs. Due to uncertainties in where, and how many, leachate samples
are possible (1 or 2), and the level of difficulty in obtaining the samples (depending on location), TRC
has prepared the budget such that most sampling scenarios will be covered. TRC may adjust the
invoice(s) accordingly. The following represent anticipated costs for three tasks within Phase 1.
1. Site Visit and Records Review ......................................................................... $6,850
2. Leachate Sampling and Analysis ..................................................................... $7,700
3. Reporting and Project Management ............................................................ $14,000
Note: the budget includes allowances for reimbursable costs (mileage, printing).
DELIVERABLES: The project deliverables will consist of 1) a draft report describing the sampling event
data, field observations, and preliminary recommendations for leachate treatment options and
recommended landfill cover maintenance, to be reviewed with OCSWD; 2) a final report addressed to
OCSWD including their review comments, and 3) a sampling report prepared in accordance with
NCDEQ electronic data delivery (EDD) protocols and a PDF format. The report to NCDEQ will include
customary figures and data tables, a brief narrative summarizing the sampling event, plus the field and
laboratory data sheets but no other observations or recommendations.
EXCLUSIONS: TRC does not anticipate any intrusive investigation of the LFG wells, nor will these
services include recommendations for the LFG system.
TERMS AND CONDITIONS: TRC will provide the proposed services in accordance with the terms and
conditions within the existing service agreement between Draper Aden Associates (now TRC) and
Orange County Solid Waste Management.
Docusign Envelope ID: 911DA9D6-C358-4231-B7E3-0443B926487C
Mr. Robert Williams
December 6, 2024 – Closed MSW Landfill Leachate PFAS Study – Phase 1
Page 4 of 5
CLOSING: TRC appreciates the opportunity to work with Orange County on this important project and
we look forward to providing our services. Please tell us if you have questions or need more information
about our proposal.
Sincerely,
G. David Garrett, PG, PE
Senior Project Manager
cc: Bruce Woody (OCSWM)
Cheryl Young (OCSWM)
Deborah Coakley (TRC)
Wendy Karably, TRC
Tyrus Clayton, PE (TRC)
Docusign Envelope ID: 911DA9D6-C358-4231-B7E3-0443B926487C
Mr. Robert Williams
December 6, 2024 – Closed MSW Landfill Leachate PFAS Study – Phase 1
Page 5 of 5
Orange County Solid Waste
Closed MSW Landfill Leachate PFAS Study – Phase 1
Draper Aden Associates Proposal No. 635043.9990
AUTHORIZATION TO PROCEED
_____________________________________________ ________________
Orange County Solid Waste Management Date
THIS INSTRUMENT HAS BEEN PRE-AUDITED IN THE MANNER REQUIRED BY THE LOCAL
GOVERNMENT BUDGET AND FISCAL CONTROL ACT:
____________________________________________ ________________
Office of the Chief Financial Officer Date
THIS SCOPE OF WORK IS SUBMITTED PURSUANT TO THE TERMS OF THE AGREEMENT DATED
FEBRUARY 22, 2017
BETWEEN DRAPER ADEN ASSOCIATES AND ORANGE COUNTY.
____________________________________________ _______________
C. Tyrus Clayton, Jr., PE Date
Budget Code: 50351020-805000
Docusign Envelope ID: 911DA9D6-C358-4231-B7E3-0443B926487C
12/13/2024
12/13/2024
12/16/2024