HomeMy WebLinkAbout10-07-19 City Commission Packet Materials - C9. TO with Tetra Tech for Groundwater and Methane Monitoring at Bozeman Landfill
Commission Memorandum
REPORT TO: Honorable Mayor and City Commission
FROM: Shawn Kohtz, City Engineer
SUBJECT: Task Order – Fiscal Year 2020 Groundwater and Perimeter Methane Monitoring, Assessment of System Performance and
Effectiveness
AGENDA ITEM TYPE: Consent MEETING DATE: October 7, 2019
RECOMMENDATION: Authorize the City Manager to execute the attached Task Order for
fiscal year 2020 Groundwater and Perimeter Methane Monitoring, Assessment of System Performance and Effectiveness at the Story Mill Landfill.
BACKGROUND: The purpose of this task order is to continue semi-annual groundwater
monitoring and monthly perimeter methane monitoring through June 2020 and to evaluate
performance of the remediation systems and their effect on adjacent groundwater quality. This task order modifies the period of services to match the City’s fiscal year rather than previous calendar year task orders and will have an effective date of July 1, 2019 through June 30, 2020.
The purpose of the semi-annual groundwater monitoring and monthly perimeter methane
monitoring activities is to maintain regulatory compliance. The purpose of the evaluation of the
remediation systems is to document performance and effectiveness of the Air Sparging and Soil Vapor Extraction systems. This task order will be implemented under the professional services agreement referenced here: http://weblink.bozeman.net/WebLink8/0/doc/63070/Electronic.aspx.
UNRESOLVED ISSUES: None.
FISCAL EFFECTS: The cost of this work will be $94,017.00. This work will be paid for with solid waste funds.
ALTERNATIVES: As suggested by the City Commission.
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Attachments: Task Order – 2019-2020 - Groundwater and Perimeter Methane
Monitoring, Assessment of System Performance and Effectiveness
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Tetra Tech
851 Bridger Drive, Suite 6; Bozeman, MT 59715
Tel 406.582.8780 Fax 406.582.8790 tetratech.com
TASK ORDER
2019 - 2020 GROUNDWATER AND PERIMETER METHANE MONITORING
ASSESSMENT OF SYSTEM PERFORMANCE AND EFFECTIVENESS
BOZEMAN LANDFILL February 28, 2019
CLIENT: CONSULTANT: The City of Bozeman Tetra Tech, Inc. P.O. Box 1230 851 Bridger Drive, Ste 6
Bozeman, Montana 59711-1230 Bozeman, MT 59718 Attention: Mr. Shawn Kohtz, PE Attention: Mr. Kirk A. Miller
INTRODUCTION
The purpose of this task order is the following:
■ Conduct semi-annual compliance groundwater monitoring and monthly perimeter
methane monitoring at the Bozeman Landfill between July 1, 2019 and June 30, 2020, per DEQ Solid Waste requirements.
■ Conduct detailed evaluations of the performance of the remediation systems and their effect upon groundwater remediation per DEQ’s June 6, 2014 letter requiring the City of
Bozeman to conduct a Corrective Measures Assessment and implement remedial
measures.
The purpose of the semi-annual groundwater monitoring and monthly perimeter methane
monitoring activities is to maintain regulatory compliance associated with the original closure of the Class II landfill. The monitoring would be conducted as in previous monitoring events.
The purpose of the evaluation of the remediation system would be to document performance and effectiveness and progress towards meeting groundwater and soil gas remediation goals.
The remediation system is comprised of the expanded landfill gas (LFG) collection system, the soil vapor extraction (SVE) system, and the air injection (AI) system. All of these systems would be evaluated.
Groundwater monitoring wells were installed, and a groundwater monitoring program was implemented beginning in 1981. Monitoring results have shown that groundwater quality has
been impacted primarily by VOCs originating from the Bozeman Landfill’s unlined waste cell. Ten additional monitoring wells were installed during 2014 and increased the total number of
monitoring stations to 33. Monitoring results indicate a southwesterly to westerly groundwater
flow. Tetrachloroethene has exceeded regulatory standards in groundwater, on City of Bozeman park property adjacent to the landfill property. Based upon recommendations from the Initial
Remediation System Evaluation report (March 9, 2018), we recommend two additional
groundwater monitoring events be conducted for the next year or two so that quarterly data is
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Task Order – 2019 to 2020 Groundwater and Methane Monitoring and Assessment Bozeman Landfill, Bozeman, Montana
February 28, 2019
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available for water quality trending analysis. Hence, September 2019 and March 2020 groundwater monitoring events are proposed to supplement the December 2019 and June 2020 monitoring events that conducted for compliance with DEQ’s landfill closure requirements.
SCOPE OF SERVICES
This task order includes the following work activities:
• Task 100 - Perimeter Methane Monitoring
• Task 200 - Additional Groundwater Monitoring Events
• Task 300 - December 2019 Compliance Groundwater Monitoring
• Task 400 - June 2020 Compliance Groundwater Monitoring
• Task 500 - Project Management, Statistical Analysis, and Reporting
The scope of work for these tasks are outlined below.
Task 100 Perimeter Methane Monitoring Task 1 includes 12 months (from July 2019 to June 2020) of methane monitoring activities.
Monitoring is conducted on a monthly basis in eight gas monitoring wells (designated BLG- wells). Gas collected in these wells will be monitored for methane, carbon dioxide and oxygen (with
remaining balance as nitrogen) in percent by volume using City of Bozeman’s landfill gas (LFG)
analyzer. Monitoring results will be entered into a database and forwarded to City of Bozeman and DEQ - Solid Waste Bureau following each monitoring event.
Task 200 Additional Groundwater Monitoring Events - September 2019 and March 2020
Two additional groundwater monitoring events are included in this task order to provide for
quarterly data for the year. This data will contribute to the continued assessment of the performance of the remediation system. Groundwater monitoring will be conducted in wells LF-2,
LF-3, MW-12, MW-17, MW-18, and MW-20.
The wells will be purged prior to sampling, have field parameters measured (including
temperature, pH, specific conductivity, dissolved oxygen, and oxidation reduction potential), and
have samples collected for volatile organic compounds (VOCs in accordance with Method 8260 low level). Two quality assurance/quality control (QA/QC) samples will be collected and prepared
during this monitoring event. These will be 1) a duplicate sample collected at a monitoring site and submitted for VOCs in accordance with Method 8260 and 2) a trip blank prepared by Pace Analytical Laboratories, shipped with the sample bottles, traveling with sample bottles in the field,
and returned to the laboratory for analysis of VOCs. Task 300 December 2019 Compliance Groundwater Monitoring
The first groundwater monitoring event contained in this task order will be conducted in December 2019 as part of the routine groundwater monitoring at the Bozeman Landfill. Tetra Tech will
perform groundwater monitoring in accordance with Tetra Tech’s Groundwater Monitoring
Sampling Analysis Plan. Groundwater monitoring will be conducted in existing groundwater
monitoring wells or stations. The scope of the monitoring event will be similar to the typical June
monitoring events but will have additional analyses for metals, cations, and nitrogen. A monitoring, sampling, and analysis matrix for the December 2019 monitoring event is presented in Table 2.
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Task Order – 2019 to 2020 Groundwater and Methane Monitoring and Assessment Bozeman Landfill, Bozeman, Montana
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Field parameter monitoring and collection of water samples will be conducted in 24 monitoring sites/wells as specified in Table 2. Water levels will be measured in all monitoring wells at the site.
Wells will be purged prior to sampling. Field parameters including temperature, pH, and specific conductivity. Field parameters will generally be measured during and at the conclusion of purging
the monitoring wells. The field parameters: dissolved oxygen and oxidation reduction potential will
be measured if winter weather conditions are at or above freezing.
Water samples will be collected and shipped to Pace Analytical Laboratories (in Billings, Montana)
for analysis of constituents shown in Table 2. The scope of analysis includes many of the constituents listed in Appendix I, 40 CFR Part 258 (July 1, 2008) in ARM 17.50.1306. Table 2
also reflects DEQ approved changes to the monitoring schedule of specified monitoring wells. Five quality assurance/quality control (QA/QC) samples will be collected and prepared during the
December 2019 assessment monitoring event. These will be 1) three duplicate samples collected at selected monitoring sites and submitted for analysis of all constituents included in Table 2; 2) two trip blanks prepared by Pace Analytical Laboratories, shipped with the sample bottles,
traveling with sample bottles in the field, and returned to the laboratory for analysis of VOCs; and 3) one decontamination blank collected from decontaminated, non-dedicated sampling equipment.
Task 400 June 2020 Compliance Groundwater Monitoring
A groundwater monitoring event will be conducted in June 2020 as part of the routine groundwater monitoring at the Bozeman Landfill. Tetra Tech will perform groundwater monitoring in
accordance with Tetra Tech’s Groundwater Monitoring Sampling Analysis Plan. Groundwater
monitoring will be conducted in existing groundwater monitoring wells or stations. A monitoring, sampling, and analysis matrix for the June 2020 monitoring event is presented in Table 1.
Field parameter monitoring and collection of water samples will be conducted in 26 monitoring sites/wells as specified in Table 1. Water levels will be measured in all monitoring wells at the site.
Wells will be purged prior to sampling. Field parameters including temperature, pH, specific
conductivity, dissolved oxygen, and oxidation reduction potential will be measured at all monitoring wells/stations where water samples will be collected. Field parameters will generally be
measured during and at the conclusion of purging the monitoring wells.
Water samples will be collected and shipped to Pace Analytical Laboratories (in Billings, Montana)
for analysis of constituents shown in Table 1. The scope of analysis includes many of the constituents listed in Appendix I, 40 CFR Part 258 (July 1, 2008) in ARM 17.50.1306. Table 1 also reflects DEQ approved changes to the monitoring schedule of specified monitoring wells.
Five quality assurance/quality control (QA/QC) samples will be collected and prepared during the June 2018 assessment monitoring event. These will be 1) three duplicate samples collected at
selected monitoring sites and submitted for analysis of all constituents included in Table 1; 2) two trip blanks prepared by Pace Analytical Laboratories, shipped with the sample bottles, traveling
with sample bottles in the field, and returned to the laboratory for analysis of VOCs; and 3) one
decontamination blank collected from decontaminated, non-dedicated sampling equipment.
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The purchase of one dedicated pump is included in this monitoring event, in the event of failure of a dedicated pump. Currently, pumps are used in wells LF-3, MW-4, MW-5, MW-6, MW-6B, and MW-8C.
Task 500 Project Management, Statistical Analysis, and Reporting
Project management will include progress reporting, scheduling of personnel, preparation/calibration of monitoring equipment/meters, supplies procurement, and other related
activities; communication with City of Bozeman and DEQ; data management; administration/
invoicing; and task order preparation for 2020 monitoring activities. Following the completion of each groundwater monitoring event and receipt of laboratory results, DEQ will also be notified,
in a letter report, as to which monitoring stations have regulatory exceedances of VOCs, metals, and/or inorganic constituents.
Groundwater monitoring data will be entered into the project database and two reports will be prepared for the June 2019 and December 2019 groundwater monitoring events. Note that the data for the June 2019 report will be collected under the existing Task Order for the 2018/2019
period. The June 2020 data collected under this Task Order will be compiled into a report under a subsequent Task Order for the 2020/2021 period. This is necessary due to the start of the new fiscal year being just weeks after the June groundwater monitoring event is conducted,
which does not provide adequate time for the report to be completed before the end of the fiscal year covered by this Task Order. A statistical analysis of analytical constituents exceeding the groundwater protection or regulatory standards will be conducted in each of these groundwater
monitoring events. The statistical analysis has been and will continue to be conducted in accordance with DEQ requirements (ARM 17.50.1305 (7-11)).
In addition, a third remediation evaluation report will be prepared evaluating 2019 system data. The third remediation evaluation report will assess the expanded landfill gas (LFG) collection
system, the soil vapor extraction (SVE) system, and the air injection (AI) system. The March and
September 2018 groundwater monitoring results will be included along with interpretations of the data, conclusions, and recommendations for further investigation and/or monitoring. This
report will be submitted to the City of Bozeman in early 2020 and then to DEQ, following City of
Bozeman approval.
PERIOD OF PERFORMANCE
Assuming approval of this Task Order prior to the start of the 2020 fiscal year, Tetra Tech’s
anticipated schedule to complete the above described activities will be the following: Deliverable Completion Date
Methane Perimeter Monitoring July 1, 2019 to June 30, 2020
September Groundwater Monitoring September 30, 2019
December Groundwater Monitoring December 31, 2019
March Groundwater Monitoring March 31, 2020
June Groundwater Monitoring June 30, 2020
June 2019 Groundwater Monitoring Report September 30, 2019
December 2019 Groundwater Monitoring Report March 31, 2020
2019 Remediation System Evaluation Report March 31, 2020
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Task Order – 2019 to 2020 Groundwater and Methane Monitoring and Assessment Bozeman Landfill, Bozeman, Montana
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COSTS Estimated costs to complete the foregoing scope of services are in shown below:
Task Description Estimated Cost
Task 100 Perimeter Methane Monitoring $5,842
Task 200 Quarterly Monitoring Events - March and September 2019’ $9,145
Task 300 December 2019 Groundwater Monitoring $21,485
Task 400 June 2020 Groundwater Monitoring $17,485
Task 500 Project Management, Statistical Analysis, and Reporting $40,420
Total $94,017
Our costs will be on a time and materials basis. A detailed cost estimate can be provided upon
request.
SPECIAL CONDITIONS: Execution of this Task Order constitutes acceptance of all terms and
conditions contained in Tetra Tech’s Professional Services Agreement with the City of Bozeman, dated April 15, 2014.
CLIENT: CONSULTANT: City of Bozeman Tetra Tech
By: By:
Printed Name: Printed Name: Kirk A. Miller
Its: Its: Senior Project Manager
Date: Date: September 25, 2019
NOTICE OF CONFIDENTIALITY This Task Order (including attachments) contains information confidential to Tetra
Tech, Inc., its subsidiaries, and subcontractors. It is intended only for City of Bozeman to consider Tetra Tech
providing professional services at the Bozeman Landfill. Any other use is prohibited, without the prior written consent
of Tetra Tech.
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