Biosolids Management Study

Biosolids Management StudyDecember 20, 2019
Prepared for: Town of Norman Wells 3 Mackenzie Drive Norman Wells, NU X0E 0V0 Prepared by: Stantec 4910 – 53 Street, PO Box 1777 Yellowknife, NT X1A 2P4 Tel: (867) 920-2882 Fax: (867) 920-4319
Project Number: 144902502
Revision Description Author Quality Check Independent Review 01 First Draft LL/TC 19/12 GP 20/19 AF 20/12
BIOSOLIDS MANAGEMENT STUDY
This document entitled Biosolids Management Study was prepared by Stantec Architecture Ltd. (“Stantec”) for the account of Town of Norman Wells (the “Client”). Any reliance on this document by any third party is strictly prohibited. The material in it reflects Stantec’s professional judgment in light of the scope, schedule and other limitations stated in the document and in the contract between Stantec and the Client. The opinions in the document are based on conditions and information existing at the time the document was published and do not take into account any subsequent changes. In preparing the document, Stantec did not verify information supplied to it by others. Any use which a third party makes of this document is the responsibility of such third party. Such third party agrees that Stantec shall not be responsible for costs or damages of any kind, if any, suffered by it or any other third party as a result of decisions made or actions taken based on this document.
Prepared by (signature)
Lalith Liyanage, P.Eng
Prepared by (signature)
Theresa Chow, E.I.T
Reviewed by (signature)
Glenn Prosko, P.Eng
Approved by (signature)
Arlen Foster, P.Eng
Table of Contents
1.0 INTRODUCTION .......................................................................................................... 1.1 1.1 BACKGROUND ............................................................................................................ 1.1 1.2 PROJECT SCOPE ....................................................................................................... 1.3 1.3 BIOSOLIDS QUANTITIES ............................................................................................ 1.3
1.3.1 Survey Methodology and Equipment ........................................................... 1.3 1.3.2 Results ........................................................................................................ 1.5
1.4 BIOSOLIDS QUALITY .................................................................................................. 1.6 1.4.1 Sludge Sampling ......................................................................................... 1.6
2.0 BIOSOLIDS PROCESSING AND UTILIZATION OPTIONS ......................................... 2.1 2.1 SLUDGE VS BIOSOLIDS ............................................................................................. 2.1 2.2 CLIMATE ...................................................................................................................... 2.1 2.3 GEOLOGY AND TERRAIN .......................................................................................... 2.2 2.4 HUMAN RESOURCES ................................................................................................. 2.2 2.5 BIOSOLIDS PROCESSING VS BIOSOLIDS UTILIZATION ......................................... 2.3 2.6 BIOSOLIDS PROCESSING OPTIONS ......................................................................... 2.3
2.6.1 Geotubes .................................................................................................... 2.4 2.6.2 Freeze/Thaw Dewatering ............................................................................ 2.1 2.6.3 Mechanical Dewatering with Rental Equipment ........................................... 2.1 2.6.4 Dewatering Recommendation ..................................................................... 2.1
3.0 REGULATORY ASPECTS ........................................................................................... 3.1 3.1 BIOSOLIDS CLASSIFICATION .................................................................................... 3.2
3.1.1 Class A Biosolids ........................................................................................ 3.3 3.1.2 Class B Biosolids ........................................................................................ 3.3
3.2 STAKEHOLDER DIALOGUE ....................................................................................... 3.4
4.0 AVAILABLE OPTIONS FOR FINAL UTILIZATION ..................................................... 4.1 4.1 INTRODUCTION .......................................................................................................... 4.1 4.2 LAND APPLICATION AND SOIL AMENDMENT ALTERNATIVES ............................... 4.1
4.2.1 Agricultural Land Application ....................................................................... 4.2 4.2.2 Land Application to Non-Agricultural Land................................................... 4.4 4.2.3 Biomass Production (Willow Coppice) ......................................................... 4.6 4.2.4 Composting ................................................................................................. 4.7 4.2.5 Soil Product Production ............................................................................... 4.8 4.2.6 Lime Stabilization (Alkaline Stabilization) .................................................... 4.9 4.2.7 Use as Landfill Cover .................................................................................. 4.9 4.2.8 Lagoon Storage......................................................................................... 4.10
5.0 TECHNOLOGY SCREENING – FINAL UTILIZATION OPTIONS ................................ 5.1 5.1 SCREENING CRITERIA............................................................................................... 5.1 5.2 DESCRIPTION OF SCREENED OPTIONS.................................................................. 5.2
6.0 SCREENED OPTIONS ................................................................................................ 6.1
Introduction
iii
6.1 RECOMMENDED CONCEPT ...................................................................................... 6.1 6.2 PROPOSED OPERATING AREA ................................................................................. 6.1 6.3 PROPOSED FACILITIES ............................................................................................. 6.1 6.4 RECOMMENDED SCOPE OF WORK ......................................................................... 6.1 6.5 BUDGET COST ESTIMATE ......................................................................................... 6.2 6.6 OPERATIONAL CONSIDERATIONS ........................................................................... 6.2
6.6.1 Final Utilization ............................................................................................ 6.2
LIST OF TABLES Table 1.1: Construction Details of the Lagoon System ............................................................. 1.3 Table 1.2: Lagoon sludge survey results (Hydrasurvey, 2019) ................................................. 1.5 Table 1.3: Cell #1 and Cell #2 Sludge Characterization Data ................................................... 1.8 Table 2.1: Climate for Norman Wells, NT (Government of Canada 2018) ................................ 2.2 Table 2.2: Potential Geotube Options for Norman Wells .......................................................... 2.6 Table 3.1: Class A and Class B Biosolids Metal Concentrations .............................................. 3.4 Table 4.1: Comparison of Chemical Fertilizer and Biosolids ..................................................... 4.2 Table 4.2: The Advantages and Disadvantages of Land Application of Biosolids ..................... 4.3 Table 4.3: Advantages and Disadvantages of Non-Agricultural Land Application of
Biosolids .................................................................................................................... 4.5 Table 4.4: Advantages and Disadvantages of Composting ...................................................... 4.8 Table 4.5: Summary of Land Application and Soil Amendment Options ................................ 4.10 Table 5.1: Preliminary Screening Criteria for Final Utilization Options ...................................... 5.1 Table 5.2:Technology Screening Summary – Final Utilization Options ..................................... 5.2
LIST OF FIGURES Figure 1.1: Town of Norman Wells Sewage Lagoon ................................................................ 1.1 Figure 1.2: Town of Norman Wells Wastewater Flow Sequence .............................................. 1.2 Figure 1.3: Inflatable boat used to conduct sludge surveys in Norman Wells
(Hydrasurvey, 2019) .................................................................................................. 1.4 Figure 1.4: GNSS base station setup (Hydrasurvey, 2019) ...................................................... 1.4 Figure 1.5: Sludge and liner measurement using sludge gun, GNSS and metered survey
rod (Hydrasurvey, 2019) ............................................................................................ 1.5 Figure 1.6: Sludge sample collection diagram .......................................................................... 1.6 Figure 1.7: Cell #1 and Cell #2 Sample Collection Locations ................................................... 1.7 Figure 2.1: Biosolids Processing and Utilization Options .......................................................... 2.3 Figure 2.2: City of Iqaluit Lagoon Sludge Management: Geotubes Being Filled ....................... 2.7 Figure 2.3: City of Iqaluit Lagoon Sludge Management: Sludge Pumping ................................ 2.8 Figure 2.4: City of Iqaluit Lagoon Sludge Management: Filtrate Collection ............................... 2.8 Figure 4.1: Liquid Biosolids being Applied to Agricultural Land ................................................ 4.3 Figure 4.2: Dewatered Biosolids being Applied to Agricultural Land ......................................... 4.4 Figure 4.3: Before-and After Picture of Reclamation at Sechelt Gravel Mine (Van Ham) .......... 4.6 Figure 4.4: 3-month old Willow (left) and Harvesting of Willow (right) ....................................... 4.7
1.0 INTRODUCTION
In August 2019, Town of Norman Wells engaged Stantec to develop a plan to estimate the sludge accumulated at the lagoon facility, characterize the sludge and develop a plan to manage the biosolids generated from the lagoon facility. This report describes the sludge survey results, characterization findings, biosolids management options evaluated, evaluation methodology and the recommendations for the biosolids management plan for the Town.
1.1 BACKGROUND
The community of Norman Wells (65° 17' N and 126° 50' W) is located in the Sahtu region of the Northwest Territories (NT) on the east bank of the Mackenzie River (Figure 1.1). It is approximately 685 km northwest of Yellowknife, NT.
Figure 1.1: Town of Norman Wells Sewage Lagoon
The wastewater treatment system in Norman Wells consists of a conveyance system for wastewater/sewage collection and an engineered Sewage Lagoon at Seepage Lake for wastewater treatment (Figure 1.2). The wastewater conveyance system includes an above-grade utilidor (with piping) and below-grade piping, sewage haul trucks, a sewage lift station, and a sewage forcemain. The Sewage Lagoon at Seepage Lake is located approximately 1 km north of the town centre. Initially, Seepage Lake
nl u:\144902502\07_sludge_survey\05-04_design_reports\norman_wells_sewage_sludge_managment_plan_rev04_20dec19.docx 1.2
was a natural wetland that was converted to an engineered Sewage Lagoon in 1987. The Sewage Lagoon at Seepage Lake is a bermed lake lagoon with two primary cells and a retention cell (Stantec 2018).
The Sewage Lagoon at Seepage Lake consists of two primary lagoon cells (110 m long by 45 m wide, 0.5 ha/cell) and a retention cell (1,086 m long by 285 m wide, approximately 28 ha) (Figure 1.2). The primary lagoon cells and berms have clay composite liners. Trucked sewage is discharged to the primary lagoon cells via a chute from a truck turnaround pad. The sewage forcemain ends at the two primary cells and flow from the sewage forcemain is controlled with a valve for each of the primary cells. An emergency overflow structure connects the two primary cells together, and two emergency overflow structures connect them to the retention cell (Figure 1.2).
Figure 1.2: Town of Norman Wells Wastewater Flow Sequence
The Sewage Lagoon operates as a closed system and was designed to be discharged (decanted) annually into an adjacent natural wetland to the east through a control valve/decant structure where the Surveillance Network Program (SNP) station S07L3-002-1 is located (Water Licence Part D, Item 6) (Figure 1.2). Decanting has generally not occurred annually but every few years. The last decanting operation occurred in 2016 (Town of Norman Wells 2017), seven years after the previous decanting
operation in 2009. The flow sequence of wastewater through the wastewater conveyance system is presented on Figure 1.2.
Construction details of the Lagoon system is given in the Table 1.1.
Table 1.1: Construction Details of the Lagoon System
Structure Primary Cell 1 Primary Cell 2 Retention Cell Liquid operating depth (m) 1.7 1.7 N/A
Active volume (m3) 12,870 12,870 784,000
Hydraulic retention time (days) 6 6 365
Freeboard depth (m) 1 1 1
Berm height 2.6 2.6 2.8
Berm top width 3 3 51
Interior berm slope 2:1 2:1 2:11
Exterior berm slope 2:1 2:1 2:11
1.2 PROJECT SCOPE
Project scope include:
1. Coordinate an on-site sludge survey to estimate the accumulated sludge quantities. The sludge survey to be based on on-site sludge depth measurement from a number of locations.
2. Conduct a sampling program to collect samples from the accumulated sludge and preserve, transport and analyzed from a third-party laboratory. At least two composite samples should be collected covering both lagoon cells, where the sludge to be disposed from.
3. Analyze the sludge management options and recommendations. Analysis to include dewatering options and biosolids disposal options.
1.3 BIOSOLIDS QUANTITIES
1.3.1 Survey Methodology and Equipment
A sludge survey was completed for both Cell #1 and Cell #2 by Hydrasurvey in July 2019. To complete the survey, an infrared sludge interface detector (sludge gun) and RTK GNSS position were used to first map out the sludge blanket. The liners of the Cells #1 and #2 were then measured using a metered survey rod, along with GNSS positioning, at the same locations as the sludge gun. Figure 1.3 shows a commercial grade inflatable inshore survey vessel that was used to access the lagoon cells. Figure 1.4 shows the dual frequency multi-constellation (DFMC) RTK based and rover GNSS system used to for mapping the sludge blanket and the data collection. Figure 1.5 shows an infrared sludge interface detector, along with an Ekman grab sampler and metered survey rod for sludge measurement.
Figure 1.3: Inflatable boat used to conduct sludge surveys in Norman Wells (Hydrasurvey, 2019)
Figure 1.4: GNSS base station setup (Hydrasurvey, 2019)
Figure 1.5: Sludge and liner measurement using sludge gun, GNSS and metered survey rod (Hydrasurvey, 2019)
The gridded interpolations of the liner depths/elevations as well as the infrared sludge detector data are summarized in Section 1.3.2 The top of the sludge surface and lagoon liner surface were used to determine the sludge and water volumes.
1.3.2 Results
Based on the survey data collected by Hydrasurvey, the estimated total sludge volume that would need to be removed from both Cells #1 and #2 was calculated using software that compared the measured and interpolated sludge depths with the depths of the lagoon liner obtained from engineered drawings and/or field. The estimated sludge volumes and mass to be removed from each cell are summarized in Table 1.2.
Table 1.2: Lagoon sludge survey results (Hydrasurvey, 2019)
Cell Number of Samples Analyzed
per Cell
be Removed (BDT)*
1.4 BIOSOLIDS QUALITY
1.4.1 Sludge Sampling
1.4.1.1 Sampling Methodology
In order to analyze the sludge characteristics from Cell #1 and Cell #2, one composite sludge sample per cell was collected for lab analysis. This section summarizes the methodology used for collecting the sludge samples. Sludge samples were collected from three to four different locations at each cell to provide a good representation of the sludge characteristics from each cell, below the water line in the lagoon, as shown in Figure 1.6.
Figure 1.6: Sludge sample collection diagram
Sampling Equipment
The sampling equipment used for sludge collection consisted of the following:
• 6 Ziploc bags; • 6 sample jars from ALS Laboratories Ltd. complete with the cooler; • 2 standard sized buckets. • 1 long pole (extendable up to 10 m). • 2 measuring cup scoopers (2-cup capacity); • Duct tape and scissors.
Sampling Steps:
The samples from Cell #1 and #2 were collected separately; however, the procedure was identical and was based on the steps as follows:
• A sludge collection device was prepared by duct taping one of the measuring cup scoopers to an extendable pole. This allowed for the collection of the sludge from the lagoon cells without the use of an inflatable boat.
• At each cell, specimens were collected from three to four different locations (depending on accessibility) and then placed into one of the two buckets. The intent was to collect several specimens from each cell to produce a representative composite sample.
• Once the specimens from the different locations within the cell were collected, the second measuring cup scooper was used to thoroughly mix the water and sludge mixture in the bucket. This produces
one composite sample for analysis. The mixture was then allowed to settle for 15 to 20 minutes to provide a fine layer of separation between the liquid phase (water) and the solids phase (soil).
• Following the settling of sludge within the mixture bucket, the water was decanted from the bucket by pouring it out into the second, empty bucket.
• Once the water was fully decanted from the sludge and water mixture, the sludge was placed evenly into the Ziploc bags and sample bottles to be shipped in the cooler to the lab for analysis.
Locations for Sample Collection at Each Cell
Figure 1.7 presents the different locations from which samples were collected at each cell, as denoted by the stars.
Figure 1.7: Cell #1 and Cell #2 Sample Collection Locations
1.4.1.2 Sampling Results
Following collection of the sludge samples from Cell #1 and Cell #2, a lab analysis was performed, and the results are summarized in Table 1.3.
Table 1.3: Cell #1 and Cell #2 Sludge Characterization Data
Parameter Units Samples
Total Kjeldahl Nitrogen % 1.41 1.29
Metals (Soil)
Parameter Units Samples Silver (Ag) mg/kg 0.97 1.59
Sodium (Na) mg/kg 328 521
Strontium (Sr) mg/kg 89.3 99.5
Sulfur (S) mg/kg 18400 18900
Thallium (Tl) mg/kg 1.21 1.33
Tin (Sn) mg/kg 9.0 8.4
Titanium (Ti) mg/kg 17.0 19.5
Tungsten (W) mg/kg <0.50 <0.50
Uranium (U) mg/kg 5.95 6.17
Vanadium (V) mg/kg 38.4 47.1
Zinc (Zn) mg/kg 483 532
Zirconium (Zr) mg/kg 3.8 3.9
A discussion of the above quality is presented in Section 5.1.
2.0 BIOSOLIDS PROCESSING AND UTILIZATION OPTIONS
2.1 SLUDGE VS BIOSOLIDS
The definitions of municipal biosolids, municipal sludge and treated septage vary across Canada. However, Canadian Council of Ministers of the Environment (CCME) defines municipal sludge and municipal biosolids as follows:
• Municipal sludge: a mixture of water and non-stabilized solids separated from various types of wastewater as a result of natural or artificial processes.
• Municipal biosolids: organic-based products which may be solid, semi-solid or liquid and which are produced from the treatment of municipal sludge. Municipal biosolids are municipal sludge which has been treated to meet to jurisdictional standards, requirements or guidelines including the reduction of pathogens and vector attraction.
Since there are no specific jurisdictional criteria for biosolids in the territory, CCME and US EPA biosolids criteria was used where applicable for the purpose of this report.
In addition to the financial capabilities of any given Town, the application of appropriate technology for biosolids processing and or utilization depends on the geology, terrain, climate and availability of the human resources to operate and maintain such facilities. Norman Wells conditions related to biosolids management are described herein.
2.2 CLIMATE Norman Wells has a subarctic climate with summer lasting for about three months. Although winter temperatures are usually below freezing, every month of the year has seen temperatures above 0°C (32 °F). Rainfall averages 171.7 mm (6.76 in) and snowfall 161.5 cm (63.58 in). On average, there are 92.9 days, October to April, when the wind chill is below -30, which indicates that frostbite may occur within 10 – 30 minutes. There is an average of 35.9 days, November to April, when the wind chill is below -40, which indicates that frostbite may occur within 5 – 10 minutes.
Based on the 1981 to 2010 Canadian Climate Normals, the average annual precipitation in Norman Wells is 294.4 millimetres (mm), including 171.7 mm as rain and 161.5 centimetres (cm) as snow (Government of Canada 2018). As outlined in Table 2.1, the average daily temperature for January is -26.1°C (the coldest month) and July is 17.1°C (the warmest month; Government of Canada 2018).
Biosolids Processing and Utilization Options
Table 2.1: Climate for Norman Wells, NT (Government of Canada 2018)
Month Average Daily Temperature (°C) Precipitation (mm) January -26.1 15.6
February -24.0 14.9
March -18.4 10.7
April -5.1 11.1
May 6.4 19.0
June 15.0 42.7
July 17.1 41.8
August 13.8 41.8
September 6.6 33.1
October -4.7 26.7
November -18.7 18.7
December -23.4 18.2
2.3 GEOLOGY AND TERRAIN Norman Wells area varies from low-lying forested plain to alpine mountainous terrain along the Norman Range, with bedrock exposures concentrated along the mountain ridges, and stream or lake outcrops. The geological interpretation in poorly exposed portions of the Mackenzie Plain has been enhanced by examination of public-domain seismic-reflection lines, archived with the National Energy Board. Cordilleran deformation from the southwest has triggered uplift of Cambrian and younger strata along reverse or thrust faults in the Franklin Mountains. The variation in trend of significant faults is believed to be due to the reactivation of older normal faults. To the southwest of the Norman Range, the Mackenzie Plain is dominated by folded Devonian and Cretaceous siliciclastic strata that have largely been planned off by glacial activity. The presence of the Saline River Formation, an evaporitic unit, in the hanging wall of larger faults suggests its involvement as a local detachment surface. An unconformity at the base of Upper Cretaceous strata cuts more deeply into underlying Lower Cretaceous and Devonian strata to the northeast, a reflection of uplift along the Keele Arch before deposition of the Slater River Formation.
Norman Wells terrain include river valley flat terrains leading to foothills and up to the mountain range.
2.4 HUMAN RESOURCES A total of 315 people identified as Indigenous, and of these, 195 were First Nations, 80 were Métis, 15 were Inuit and 20 gave multiple Indigenous responses. The main languages in the town are North Slavey and English. Of the population, 78.1% is 15 and older, with the median age being 32.8, slightly less than the NWT averages of 79.3% and 34.0.
2.5 BIOSOLIDS PROCESSING VS BIOSOLIDS UTILIZATION Biosolids processing can be categorized into two groups:
1. Technologies that reduce quantity, and 2. Technologies that improve quality
On the other hand, biosolids utilization include final disposal or utilization. Generally, more biosolids processing will result in more options being available for final utilization/disposal. The most common biosolids processing categories include:
1. Thickening (removing of water, end result varies but generally > 6% solids) 2. Dewatering (removing of water, end result varies but generally > 15% solids) 3. Drying (removing of water, end result varies but generally >60% solids), and 4. Digestion (stabilization).
An example schematic indicating the increased number of options resulting from further processing of biosolids is shown in the Figure 2.1.
Figure 2.1: Biosolids Processing and Utilization Options
2.6 BIOSOLIDS PROCESSING OPTIONS Biosolids can be dewatered utilizing dewatering technologies that are available in Norman Wells. Geotubes has also been a technology that is being used in the north to dewater sludges. Geotubes are particularly attractive to the Norman Wells as this is not a continuous operation. Biosolids stabilization or drying is not applicable as these technologies are suitable for where long term continuous sludge processing is required. As a result, dewatering utilizing:
• Rental equipment (such as centrifuge)
Cho, Theresa
Cho, Theresa
• Geotubes, and • Freeze/thaw will be evaluated.
It should be noted that some utilization options such as marginal land application, dewatering prior to application may not be necessary.…

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