The report summarizes groundwater, surface water, and leachate monitoring data collected between April 2009 and March 2010 at the Hartland landfill and surrounding area. Key findings include: (1) Groundwater flow patterns were consistent with previous years, with some northward and southeastward flow captured by purge wells. (2) Groundwater quality showed contained leachate impacts. (3) Elevated parameters near the Hartland North Pad indicated ongoing impacts from historical composting and current aggregate stockpiling. Water quality is closely monitored.
1. Prepared by:
AECOM
3292 Production Way, Floor 4 604 444 6400 tel
Burnaby, BC, Canada V5A 4R4 604 294 8597 fax
www.aecom.com
Project Number:
60158830
Date:
December 2010
Environment
Capital Regional District
Hartland Landfill Groundwater, Surface
Water and Leachate Monitoring Program
Annual Final Report (April 2009 to March
2010)
2. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt Sb.Docx
Statement of Qualifications and Limitations
The attached Report (the “Report”) has been prepared by AECOM Canada Ltd. (“Consultant”) for the benefit of the
client (“Client”) in accordance with the agreement between Consultant and Client, including the scope of work
detailed therein (the “Agreement”).
The information, data, recommendations and conclusions contained in the Report (collectively, the “Information”):
is subject to the scope, schedule, and other constraints and limitations in the Agreement and the
qualifications contained in the Report (the “Limitations”)
represents Consultant’s professional judgement in light of the Limitations and industry standards for the
preparation of similar reports
may be based on information provided to Consultant which has not been independently verified
has not been updated since the date of issuance of the Report and its accuracy is limited to the time
period and circumstances in which it was collected, processed, made or issued
must be read as a whole and sections thereof should not be read out of such context
was prepared for the specific purposes described in the Report and the Agreement
in the case of subsurface, environmental or geotechnical conditions, may be based on limited testing and
on the assumption that such conditions are uniform and not variable either geographically or over time
Consultant shall be entitled to rely upon the accuracy and completeness of information that was provided to it and has
no obligation to update such information. Consultant accepts no responsibility for any events or circumstances that may
have occurred since the date on which the Report was prepared and, in the case of subsurface, environmental or
geotechnical conditions, is not responsible for any variability in such conditions, geographically or over time.
Consultant agrees that the Report represents its professional judgement as described above and that the
Information has been prepared for the specific purpose and use described in the Report and the Agreement, but
Consultant makes no other representations, or any guarantees or warranties whatsoever, whether express or
implied, with respect to the Report, the Information or any part thereof.
The Report is to be treated as confidential and may not be used or relied upon by third parties, except:
as agreed in writing by Consultant and Client
as required by law
for use by governmental reviewing agencies
Consultant accepts no responsibility, and denies any liability whatsoever, to parties other than Client who may
obtain access to the Report or the Information for any injury, loss or damage suffered by such parties arising from
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borne by the party making such use.
This Statement of Qualifications and Limitations is attached to and forms part of the Report and any use of the
Report is subject to the terms hereof.
3. AECOM
3292 Production Way, Floor 4 604 444 6400 tel
Burnaby, BC, Canada V5A 4R4 604 294 8597 fax
www.aecom.com
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt B.Docx
December 21, 2010
Capital Regional District
Environmental Sustainability
625 Fisgard St.
P.O. Box 1000
Victoria, BC V8W 2S6
Attention: Ms. Mary Anne Fillipone, M.Sc., P.Geo.
Program Manager, GeoEnvironmental Programs
Project No: 60158830
Regarding: Hartland Landfill Groundwater, Surface Water and Leachate Monitoring
Program Annual Final Report (April 2009 to March 2010)
Dear Ms. Fillipone,
We are pleased to present our final report on the 2009/10 Hartland landfill groundwater, surface water
and leachate monitoring program. The report presents our interpretation of the impact of the Hartland
landfill on surface and groundwater resources based on monitoring data collected in 2009 and the
early part of 2010. Our main findings are outlined in an executive summary at the front of the report.
Thank you once again for the opportunity to provide this report. If you have any questions please
contact Ryan Mills in our Burnaby office at 604-444-6498.
Yours very truly,
AECOM Canada Ltd.
Robert C. Dickin, M.Sc., P.Geo.
Technical Director – Hydrogeology
Rob.Dickin@aecom.com
RM:gc
4. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt B.Docx
Distribution List
# of Hard Copies PDF Required Association / Company Name
8 1 Capital Regional District
2 1 AECOM
AECOM Signatures
Report Prepared By:
Ryan D. Mills, M.Sc.
Hydrogeologist
Stephen Dickin, B.Sc.
Hydrogeology and Geosciences Assistant
May Quach, M.Sc.
Aquatic Ecologist
Report Reviewed By:
Robert C. Dickin, M.Sc., P.Geo.
Technical Director and Senior
Hydrogeologist
5. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt Sb.Docx i
Executive Summary
Groundwater and surface water quality in the vicinity of Hartland landfill has been monitored since 1983. Annual
monitoring reports have been issued since 1988. This report presents interpretation of the groundwater and surface
water quality, as well as the leachate containment and collection systems, based on monitoring data collected
between April 2009 and March 2010. As in previous years, the data set covering this period is referred to as the
2009/10 data throughout this report. The 2009/10 monitoring data are presented and compared to previous
monitoring results to identify important trends and evaluate compliance with water quality criteria.
Based on our review of historical data and interpretation of groundwater, surface water and leachate quality data
collected between April 2009 and March 2010, the annual monitoring program provides an effective assessment of
landfill performance and compliance related to groundwater, surface water and leachate flow and quality. The
following conclusions are drawn based on our interpretation of the 2009/10 data:
Quality Assurance and Quality Control
Relative percent differences (RPD’s) and relative standard deviations (RSD’s) calculated for groundwater,
surface water and leachate analyses in 2009/10 indicate that the data is acceptably precise for the purposes of
this report. Standard operating procedures (SOP) for groundwater, surface water and leachate quality sampling
should be developed to ensure that data integrity is maintained. The development of an SOP for groundwater
level collection should also be considered. CRD is currently in the process of reviewing SOP’s and updating
them as necessary.
Groundwater Flow
Groundwater flow in 2009/10 generally followed previously established patterns. Regional groundwater flows
from Mount Work northeast to the north-south trending valley that underlies the northern portions of the Phase 1
and Phase 2 landfill. The majority of groundwater flow is northward. Most of the northward groundwater flow in
the bedrock below the landfill is captured by the Phase 2 basin leachate collection system, springs discharging
to the lower lagoon and the Phase 1 north purge well system (wells 52-4-0-P7 and 80-1-0-P8).
There is a small amount of southeastward groundwater flow from the south end of the Phase 1 landfill toward
Killarney Lake. Southeastward groundwater flow below the landfill is constrained by a clay berm and a bedrock
grout curtain installed at the south end of the landfill and by pumping of the south purge wells (P1, P2, P3 and
P4). Higher pumping elevations in P1 as a result of changes in the hydraulic behaviour of the well resulted in
reduced leachate capture between 2006 and 2009, and again from December 2009 through 2010. An additional
purge well (P10) has been installed adjacent to P1 and is anticipated to augment leachate collection in this area
of the landfill once it is operational.
Groundwater monitors east of Phase 1 (locations 76 and 18) confirm flow from east to west toward the landfill,
preventing off-site migration to the east.
Groundwater elevations north of the Phase 2 landfill remained within seasonal ranges. Inward hydraulic
gradients toward the Phase 2 basin were maintained throughout 2009/10. The effectiveness of the hydraulic
trap needs to be assessed as Phase 2 refuse extends further north and additional lifts are constructed.
Additional leachate containment measures may need to be implemented at the north end of the Phase 2 landfill
to mitigate the potential for off-site leachate migration. In future phases of development, leachate levels within
Phase 2 need to be monitored on a regular basis.
Pressure transducers installed in wells 40-1-1, 52-4-0-P7 and 80-1-0-P8 help delineate the size of the drawdown
cone surrounding the purge wells and will provide long-term monitoring of purge well performance at the north
end of Phase 1.
6. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt Sb.Docx ii
Leachate mounding continues to be present in Phase 1 of the landfill. Strong downward gradients are present
within the refuse. Similar leachate mounding conditions occur in the Phase 2 landfill as indicated by groundwater
elevations at locations 82 and 83. Both wells at location 84 were damaged and were replaced with permanently
installed pressure transducers in October 2010. Together with information collected from wells at locations 82
and 83, this should provide adequate monitoring of leachate levels in Phase 2 in its current configuration.
Groundwater Quality
The groundwater quality results for 2009/10 were similar to those measured in 2008/09 and landfill leachate-
impacted groundwater is contained within the landfill property. At the north end of the landfill, leachate-affected
groundwater extends just north of the unlined lower leachate lagoon and the lined upper leachate lagoon. South of
the landfill, leachate-affected groundwater extends approximately 200 m south. Leachate impacts are confined to the
landfill footprint on the east side of Phase 1 and are inferred to extend to the west side of the Phase 2 landfill.
Groundwater affected by historical composting and yard waste processing and current aggregate stockpiling
activities at the Hartland North Pad is inferred to extend just beyond the footprint of the Hartland North pad and
extend slightly north of Willis Point Road. Land use north of Willis Point Road consists of Mt. Work Regional Park
and the Dominion Government Property rifle range.
Our review of the 2009/10 groundwater quality data revealed the following:
North of the Landfill
Operation of the north purge well system (wells 80-1-0-P8 and 52-4-0-P7) continues to mitigate leachate impacts
north of the landfill, as indicated by relatively stable or slowly decreasing concentrations of leachate indicator
parameters at locations 20, 21 and 40. The operation of purge well 80-1-0-P8 since 2008 and rehabilitation of
well 52-4-0-P7 in 2008 has reinforced leachate containment and conveyance measures north of Phase 1. These
wells should continue to be operated in conjunction with one another and water quality should continue to be
closely monitored for leachate impacts at locations 20 and 21. Water quality northwest of the lower leachate
lagoon (well 40-1-1) remained impacted by leachate during 2009/10 and should continue to be closely
monitored. Recent improvements to the north purge well system combined with regular well and pump
maintenance is anticipated to further improve water quality in this area.
Well 36-3-1 and 37-3-1 continue to exhibit elevated concentrations of leachate indicator parameters in 2009/10.
The slightly impaired water quality at these locations is likely related to the Phase 2 leachate storage test
conducted in September 2008 and ongoing waste deposition in the area upgradient of locations 36 and 37.
Shallow groundwater quality should continue to be closely monitored at these locations to verify the
effectiveness of leachate containment. Cement used during well construction continues to impact well water
quality in wells 36-2-1 and 37-2-1, as it has since these wells were installed.
Significantly elevated conductivity, ammonia, chloride, nitrite, iron and manganese concentrations were
observed at location 38 in February 2008, indicating possible leachate impacts at this location. Follow-up
sampling during 2008, 2009 and the early part of 2010 indicates that all parameters have returned to
concentrations near background levels and that leachate is not impacting groundwater quality at this location.
The historically elevated concentrations are likely related to the remains of dead amphibians found in well 38.
In the shallow well located at the base of the Toutle valley (27-1-2), sulphate continues to be present at
concentrations above historical (background) concentrations throughout the year. This is likely related to
ongoing quarrying, aggregate stockpiling and road building activities in this area. The deep well at this location
(27-1-1) shows no signs of impacts from aggregate production or stockpiling.
Water quality along Willis Point Road north of the landfill at locations 29, 30 and potentially 31 continues to be
impacted by road salt application on Willis Point Road. Concentrations of conductivity and chloride show
7. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt Sb.Docx iii
seasonal fluctuations and exhibit highest concentrations in winter months, while ammonia concentrations remain
relatively low.
Water quality at location 78, located on the bedrock ridge north of Phase 2, continued to report slightly elevated
concentrations of conductivity, nitrate, sulphate and manganese in 2009/10. Additional well development efforts
were focused on this well in 2008 and water quality at this location appears to be slowly improving. The
presence of mineralized bedrock near the well may be the cause of some elevated parameters, but elevated
concentrations of conductivity, nitrate and sulphate could also be related to aggregate stockpiling within the
Phase 2 basin.
Hartland North Pad
Groundwater quality downgradient of the Hartland North Pad continues to be affected by historical composting
and aggregate stockpiling activities with elevated concentrations of conductivity, ammonia, nitrate, sulphate and
chloride at locations 41, 42, 43, 55 and 56. Elevated concentrations of conductivity, sulphate and nitrate at
locations 41, 43, 55, and potentially 56 indicate continued increasing groundwater impacts associated with the
aggregate storage and stockpiling on the Hartland North pad. Water quality exceeded British Columbia Water
Quality Guidelines for: conductivity on all sampling dates in wells at locations 41, for manganese at locations 41
and 42; and for iron at location 42. Conductivity concentrations at locations 43 and 55 were also above
guidelines on all sampling dates. A statistical trend analysis for data collected between 2005 and 2010 indicated
an increasing trend in sulphate concentrations at locations 41, 55 and 56, increasing conductivity at location 55
and decreasing chloride concentrations at location 42. Overall, this indicates slowly declining impacts from
historical composting activities and increased impacts from aggregate stockpiling on the Hartland north pad.
Water quality in the vicinity of the Hartland North Pad should continue to be monitored closely for any impacts
associated with the storage of large quantities of aggregate.
South of the Landfill
Water quality south of the landfill continued to exhibit elevated concentrations of some leachate indicator
parameters (conductivity, chloride and ammonia) in 2009/10, as it has for nearly two decades. Groundwater
quality appears to be relatively stable or gradually improving at locations 4, 19, 71, 72 and 73. Improvements in
water quality are largely the result of leachate collection and containment measures put in place in 2001 and
prior.
Water quality at locations 3 and 85, 60 and 7 degraded in 2009/10. Following a large precipitation event in
2006/07, the behaviour of the most productive south purge well (P1) changed, resulting in higher water levels
and inadequate drawdown and leachate collection south of the landfill between 2007 and 2009, and migration of
leachate southward from Phase 1 toward wells 60 and 7. In 2009, a higher capacity 1.26 L/s (20 gpm)
submersible pump was installed to increase drawdown in P1. While the submersible pump was effective in
drawing down water levels, it required more maintenance than the lower capacity bladder pumps in the adjacent
purge wells. In 2010, an additional purge well (P10) was added to increase pumping capacity and augment the
south leachate collection system. Over the past five years, there have been statistically significant increasing
trends in leachate indicator parameters in wells 60-3-1 (conductivity and chloride), 60-2-1 (chloride) and 4-2-1
(chloride). Some groundwater quality parameters have decreased slightly in wells 60-2-1 (ammonia and
sulphate), 71-1-1 (conductivity and sulphate), 72-2-1 (chloride and sulphate), 73-1-1 (conductivity), 73-2-1
(ammonia and sulphate) and 4-4-1 (chloride). An increasing trend in sulphate concentrations was also observed
in well 72-3-1. Overall, this suggests slightly greater impacts due to leachate migrating south from Phase 1, and
slowly declining impacts related to aggregate placement during construction of the bin facility in 2009 or road salt
application on Hartland Avenue.
8. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt Sb.Docx iv
East of the Landfill
Leachate impacts are confined to the landfill footprint on the east side of Phase 1. Measured groundwater
elevations have consistently indicated flow from the bedrock ridge along the east side of the site towards the
landfill at locations 18 and 76.
Domestic Well Water Quality
As part of the CRD’s groundwater quality monitoring program, eleven domestic drinking water wells within 2
kilometres of the landfill were sampled in 2009/10. The water quality monitoring program showed:
One domestic well (53) was above the drinking water criterion for total iron (0.3 mg/L), with a concentration of
0.339 mg/L. The iron concentrations in domestic well 53 have been reported as elevated for many years;
One well (61) was above the drinking water criterion for total lead in one field replicate collected during July
2009. Subsequent samples exhibited concentrations of lead that were well below drinking water guidelines
(0.00088 mg/L), indicating that elevated lead concentrations may be a result of stagnant water that was not
completely purged from household plumbing or the well prior to sampling;
Overall, the groundwater quality in the domestic wells sampled in 2009/10 was similar to previous years and
landfill leachate did not impact the eleven domestic wells sampled by the CRD in 2009/10.
Surface Water Quality
The surface water quality data collected in 2009/10 revealed that:
North of the Landfill
Surface water quality at boundary compliance stations along the northern property boundary north of Phase 1
and Phase 2 generally met water quality criteria in 2009/10, with the following exceptions:
Total iron concentrations exceeded guidelines at Sw-N-16 (March 2010) and was above water quality
guidelines at Sw-N-47 (November 2009), Sw-N-53 and Sw-N-18 (November 2009);
Total suspended solids exceeded guidelines at Sw-N-53 (November 2009); and
Sulphate concentrations exceeded guidelines at Sw-N-05 (November 2009).
At station Sw-N-07, located in Durrance Creek downstream of the confluence with Heal Creek and upstream of
the confluence with Tod Creek, water quality criteria were met in 2009/10. No detectable leachate impacts to
Tod Creek have been observed for many years.
Hartland North Pad
Surface water quality at boundary compliance stations north of the Hartland North pad generally met water
quality criteria on all dates sampled in 2009/10, with the exception of the following:
Sulphate concentrations exceeded guidelines at Sw-N-41s1 (six out of six sampling dates) and were
elevated at Sw-N-41s3 (one out of four sampling dates).
Elevated sulphate concentrations appear to be related to quarrying and stockpiling of aggregate north of the
Phase 2 landfill. Statistically significant increasing trends in conductivity (Sw-N-41s1) and sulphate (Sw-N-41s1
and Sw-N-42s1) are present in data collected between 2005 and 2010, suggesting that the impacts of aggregate
stockpiling on the Hartland North pad have continued to worsen since stockpiling began in 2006. Elevated
sulphate concentrations were present at Sw-N-42s1 throughout 2009/10, where impacts of both historical
composting and aggregate stockpiling are evident. CRD is currently investigating options to manage site runoff
to reduce sulphate peaks. Data collected from sampling locations downstream of Sw-N-41-S1 showed an
9. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt Sb.Docx v
improvement in water quality with distance from the Hartland North Pad. Water quality in Durrance Lake is not
affected by the Hartland North Pad or the landfill.
South of the Landfill
Surface water quality at boundary compliance stations south of the landfill generally met water quality criteria on
all dates sampled in 2009/10, with the exception of the following:
Total iron concentrations exceeded guidelines at Sw-S-03 (two out of six sampling dates) and Sw-S-04
(one out of six sampling dates); and
Total suspended solids exceeded guidelines at Sw-S-03 (November 2009) and Sw-S-04 (November
2009 and January 2010). This is likely a short term issue related to runoff and erosion of the clay cover
material installed on the southeast portion of Phase 1 prior to establishment of vegetation. Vegetation
has since been established by CRD.
Surface water quality immediately south and southeast of the landfill (Sw-S-03 and Sw-S-04) continued to
improve during 2009/10. Concentrations were similar to previous years and minimal effects were seen further
downstream to the south of the landfill.
Water quality in Killarney Lake (Sw-S-10) in 2009/10 met water quality guidelines and showed no measurable
impacts from leachate.
Leachate
The leachate flow and quality data collected in 2009/10 indicates that:
Leachate discharges remained in compliance with Regional Source Control Program (RSCP) permit
requirements during 2009/10. Two samples reported values above the permit criterion: oil and grease
concentrations marginally exceeded the 15 mg/L guideline with a value of 16 mg/L in October 2009 and total
polycyclic aromatic hydrocarbons marginally exceeded the 50 μg/L guideline with a concentration of 56 μg/L in
February 2010. This is the first time either of these constituents have been reported at a value above the permit
criteria. A second sample collected late in October 2010 reported and oil and grease value that was less than
the permit criteria and within the range of historical values at this station. The concentrations of most leachate
constituents at the Hartland valve chamber in 2009/10 were generally within the range of historical values.
Average leachate flow in 2009/10 was 13.62 L/s, with a maximum monthly flow of 75,489 m3
(28.18 L/s) for
January 2010. This is significantly lower than the flows observed during 2006/07, but similar to flows observed in
2007/08 and 2008/09 and the long-term (1997 to 2010) average of 12.21 L/s).
The concentrations of leachate constituents measured in 2009/10 were similar to previous measurements.
Lower precipitation in 2009/10 appears to have resulted in leachate with similar strength compared to 2008/09,
but stronger than 2006/07 and 2007/08.
A total of 16 trace organic compounds out of the 103 analyzed were detected in 50% or more of the samples
during 2009/10, similar to previous years. Reported concentrations in leachate were generally very low for a
municipal waste landfill. The types of compounds that were detected were typical of leachate from other landfills
AECOM is familiar with. Concentrations of all trace organic parameters were in compliance with the RSCP
permit criteria.
10. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt Sb.Docx vi
Recommendations
Based on the findings of this report the following recommendations are proposed:
Leachate Collection System
The north and south purge wells should continue to operate, as these wells help control the movement of
leachate impacted groundwater. The operation of both purge wells (52-4-0-P7 and 80-1-0-P8) located at the
north end of the landfill is anticipated to continue to improve leachate containment north of Phase 1. The
following guidelines should be followed:
a) Pumping levels in wells 52-4-0-P7 and 80-1-0-P8 should continue to be maintained at 113.5 m ASL.
Pumping levels in P1, P10 and the remainder of the south purge wells (P2, P3 and P4) should be
maintained at an elevation below 140 m ASL to maximize leachate collection.
b) Leachate purge wells should be operated on a continuous basis except for periods when the leachate
conveyance and storage facilities are at capacity. Regular maintenance and replacement of pumps and
wells as a result of ongoing biofouling and encrustation is very important.
c) Pumping levels and the extent of the drawdown cones surrounding the purge wells should be validated twice
annually to confirm the proper functioning of the wells.
d) Water levels in the south purge wells and water quality south of Phase 1 (location 85, 60 and 7) should be
closely monitored to confirm that the drawdown cone around P1 has been restored following the installation
of an additional purge well (P10) to provide additional pumping capacity.
e) A standard operating procedure should be developed for verification of drawdown and the extent of the
drawdown cone surrounding both the north and south purge well systems during both wet and dry months.
Runoff from Aggregate Stockpiles
Groundwater and surface water quality downgradient of the northwest sedimentation pond and the Hartland
North Pad should continue to be monitored closely for impacts related to aggregate production and stockpiling.
A long-term strategy for managing runoff from aggregate stockpiles should be given serious consideration. This
may include minimizing the volume of aggregate stored on the Hartland North pad and installing tarps to
minimize infiltration and recharge below aggregate stockpiles.
Groundwater Flow North of Phase 2
Further investigation is recommended to define the groundwater flow system north of the western unfilled portion of
the Phase 2 landfill during 2011. Defining seasonal water table fluctuations and groundwater flow paths in this area
is important for assessing the potential for northward leachate migration from this area as the landfill footprint and
height of refuse increases to the northwest. Specific recommendations include:
a) Installation of pressure transducers connected to the SCADA system at monitoring well locations 78 and 79
to provide continuous daily records of water level variation north of Phase 2, to better define the
groundwater divergence and to verify leachate containment as landfilling progresses in Phase 2. A pressure
transducer has already been installed in well 79-1-1, but data is currently downloaded to a laptop as no
SCADA infrastructure is available at this location at this time.
b) Two new nested monitoring wells should be installed at locations upgradient and downgradient of location
79 as access permits to better define the groundwater flow pathways north of the landfill. Water levels
should be recorded at least six times annually and samples collected quarterly from each of the wells;
c) Newly installed pressure transducers at location 86 should be connected to the SCADA system to record
leachate levels within Phase 2 at least once per day; and
11. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt Sb.Docx vii
d) The leachate management design for the area north of Phase 2 should be reviewed and assessed from a
hydrogeological perspective. The existing three-dimensional groundwater model could be used to validate
the hydrogeological conditions surrounding the landfill. The model would enable the evaluation of
groundwater flow and potential contaminant migration pathways under various landfill design scenarios to
support long-term leachate containment planning.
Monitoring Program
Monitoring of groundwater, surface water and leachate quality and flow should continue and include the following:
Groundwater quality changes observed in well 40-1-1 located between the upper and lower lagoons should
continue to be closely monitored to ensure that the extent of the drawdown cone associated with the purge wells
is sufficient to capture leachate-impacted groundwater near location 40;
Groundwater quality at locations 36 and 37 should be closely monitored to ensure that the effects of the leachate
storage tests conducted in 2007 and 2008 continue to diminish. Even short term exceedences of the hydraulic
trap could have multi-year implications on nearby groundwater quality. Continued monitoring will help to
understand the sensitivity of groundwater quality in wells 36 and 37 to water levels within Phase 2.
Additional well development employing inertial pumps and surge blocks should be conducted at locations 76, 78,
79 and 85 to improve hydraulic connection to the aquifer and reduce suspended sediment in samples. This has
been shown to improve the quality of samples collected at other wells on site.
The sampling frequency at surface water station Sw-N-45 should be increased from four to six times annually.
Based on water levels recorded in 2009/10, monitor 74-1-1 appears to be blocked or damaged. Because the
deep bedrock groundwater flow system underlying Phase 1 has remained relatively stable for a long time and is
well understood, well 74-1-1 does not need to be replaced at this time. It should be removed from the monitoring
program.
For water quality exceedences reported in domestic wells CRD staff should continue to report results to the well
owner.
The results of the annual monitoring program should continue to be reviewed and interpreted by a qualified
professional experienced in assessing the impacts of landfill leachate at large municipal landfills similar to
Hartland.
Quality Assurance and Quality Control
Standard operating procedures (SOP’s) should be reviewed or developed for sampling groundwater, surface
water and leachate to ensure consistency between measurements and sampling events and maintain data
integrity. An SOP for domestic well sampling should also be developed to help reduce the potential for sampling
bias and interferences associated with lead solder, copper pipe and galvanized plumbing.
Quality assurance laboratory analyses and laboratory precision should be evaluated quarterly, and any
discrepancies should be resolved with the laboratory and sampling personnel within a month of receiving the
laboratory results. The appropriate notation should be added to the data files that explain the reason for the low
precision and the steps taken, if any, to improve the sampling or laboratory procedures.
Construction Management
Appropriate erosion control measures should be put in place to minimize total suspended solids in runoff from
construction areas for all projects involving excavation or soil relocation.
12. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt Sb.Docx
Table of Contents
Statement of Qualifications and Limitations
Letter of Transmittal
Distribution List
Executive Summary
page
1. Introduction.....................................................................................................................................1
2. Site Description...............................................................................................................................4
2.1 Physiography....................................................................................................................................... 4
2.2 Geology ............................................................................................................................................... 4
2.3 Climate................................................................................................................................................. 4
3. Methodology....................................................................................................................................5
3.1 Field Techniques ................................................................................................................................. 5
3.2 Sample Analysis and Quality Assurance............................................................................................. 6
3.2.1 Relative Percent Difference – Groundwater and Surface Water............................................ 6
3.2.2 Relative Standard Deviation and Relative Percent Difference - Leachate........................... 10
3.3 Summary ........................................................................................................................................... 10
4. Groundwater Flow ........................................................................................................................15
4.1 Data ................................................................................................................................................... 15
4.2 Regional Groundwater Flow in the Bedrock...................................................................................... 15
4.3 Groundwater and Leachate Flow – Phase 1 ..................................................................................... 19
4.4 Groundwater and Leachate Flow – Phase 2 ..................................................................................... 28
4.5 Summary ........................................................................................................................................... 29
5. Groundwater Quality in Monitoring Wells Near the Landfill.....................................................31
5.1 Data ................................................................................................................................................... 31
5.2 Average Electrical Conductivity......................................................................................................... 34
5.3 Monitors North of the Phase 1 Landfill .............................................................................................. 38
5.4 Monitors West and North of the Phase 2 Landfill and Near the Hartland North Pad ........................ 42
5.4.1 Background Wells................................................................................................................. 42
5.4.2 Wells North of Phase 2 Landfill ............................................................................................ 43
5.4.3 Hartland North Pad............................................................................................................... 46
5.5 Monitors South of the Phase 1 Landfill.............................................................................................. 48
5.6 Monitors East of the Phase 1 Landfill................................................................................................ 53
5.7 Summary ........................................................................................................................................... 55
6. Groundwater Quality in Domestic Wells.....................................................................................57
6.1 Data ................................................................................................................................................... 57
6.2 Domestic Well Quality........................................................................................................................ 57
6.3 Summary ........................................................................................................................................... 59
7. Surface Water Flow and Quality Near the Landfill.....................................................................61
7.1 Data ................................................................................................................................................... 61
7.2 Surface Water Flow and Quality North of the Landfill ....................................................................... 66
7.2.1 Surface Water Quality North of Phase 1 and Phase 2......................................................... 66
13. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
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7.2.2 Surface Water Quality Near the Hartland North Pad............................................................ 69
7.3 Surface Water Flow and Quality South of the Landfill....................................................................... 73
7.4 Summary ........................................................................................................................................... 76
8. Leachate ........................................................................................................................................77
8.1 Data ................................................................................................................................................... 77
8.2 Leachate Generation and Discharge................................................................................................. 77
8.3 Leachate Quality................................................................................................................................ 77
8.3.1 Routine Monthly Leachate Analyses and Sewer Use Bylaw Comparison ........................... 78
8.3.2 Quarterly Trace Organic Analysis at Hartland Valve Chamber............................................ 81
8.4 Summary ........................................................................................................................................... 82
9. Conclusions ..................................................................................................................................83
9.1 Quality Assurance and Quality Control.............................................................................................. 83
9.2 Groundwater Flow ............................................................................................................................. 83
9.3 Groundwater Quality.......................................................................................................................... 84
9.4 Domestic Well Water Quality............................................................................................................. 86
9.5 Surface Water Quality........................................................................................................................ 86
9.6 Leachate ............................................................................................................................................ 87
10. Recommendations........................................................................................................................88
11. Disclaimer......................................................................................................................................90
12. Qualifications of the Authors.......................................................................................................91
13. References.....................................................................................................................................92
List of Figures
Figure 1-1. Site Location Map....................................................................................................................................... 2
Figure 4-1. Bedrock Groundwater Elevations and Flow Directions in Plan................................................................ 16
Figure 4-2. Groundwater Flow in Cross Section A-A’................................................................................................. 17
Figure 4-3. Groundwater Flow in Cross Section B-B’................................................................................................. 18
Figure 4-4. Groundwater Elevations East of Phase 1 ................................................................................................ 20
Figure 4-5. Leachate and Groundwater Elevations Within Phase 1 .......................................................................... 22
Figure 4-6. Groundwater Elevations Surrounding the North Purge Wells.................................................................. 24
Figure 4-7. Groundwater Elevations in South Purge Wells........................................................................................ 26
Figure 4-8. Water Elevations Within the Leachate Conveyance System and Surrounding the Phase 2 Basin......... 27
Figure 5-1. Electrical Conductivity in Plan.................................................................................................................. 35
Figure 5-2. Electrical Conductivity in Cross Section A-A’........................................................................................... 36
Figure 5-3. Electrical Conductivity in Cross Section B-B’........................................................................................... 37
Figure 5-4. Groundwater Quality North of Phase 1 .................................................................................................... 39
Figure 5-5. Groundwater Quality North of Willis Point Road...................................................................................... 41
Figure 5-6. Groundwater Quality North of Phase 2 .................................................................................................... 44
Figure 5-7. Groundwater Quality North of Hartland North Pad .................................................................................. 47
Figure 5-8. Groundwater Quality South of Landfill ..................................................................................................... 49
Figure 5-9. Groundwater Quality Southeast of Landfill .............................................................................................. 50
14. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
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Figure 5-10. Groundwater Quality East of Landfill........................................................................................................ 54
Figure 6-1. Domestic Well Locations.......................................................................................................................... 58
Figure 7-1. Surface Water Bodies and Sampling ....................................................................................................... 62
Figure 7-2. Surface Water Quality North of Phase 1.................................................................................................. 68
Figure 7-3. Surface Water Quality North of Phase 2.................................................................................................. 70
Figure 7-4. Surface Water Quality Downstream of the Hartland North Pad............................................................... 72
Figure 7-5. Surface Water Quality South of Landfill................................................................................................... 75
Figure 8-1. Hartland Valve Chamber Leachate Chemistry (Conductivity, Ammonia and Chloride)........................... 79
Figure 8-2. Hartland Valve Chamber Leachate Chemistry (Sulphide, BOD and COD) ............................................. 80
List of Tables
Table 3-1. Ground Water Chemistry QA/QC – Relative Percent Difference............................................................... 8
Table 3-2. Surface Water Quality QA/QC – Relative Percent Difference ................................................................... 9
Table 3-3. Hartland Valve Chamber Leachate Chemistry QA/QC – Relative Standard Deviation........................... 11
Table 3-4. Hartland Valve Chamber Leachate Chemistry QA/QC – Relative Percent Difference............................ 13
Table 5-1. Groundwater Quality Exceedences.......................................................................................................... 32
Table 7-1. Hartland - Surface Water Quality – Exceedences – 2009 / 2010 ............................................................ 63
Appendices
A. Water Level Data
1. Monitoring Well Co-ordinates
2. Monitoring Well Details
3. Water Level Data
4. Surface Water Station Co-ordinates
B. Landfill Chemistry Data
1. Quarterly Landfill Groundwater Chemistry– 2009/10
Annual Landfill Groundwater Chemistry – 2009/10
2. Domestic Well Chemistry – 2009/10
3. Quarterly Surface Water Chemistry – North and South – 2009/10
Annual Surface Water Chemistry – North and South – 2009/10
4. Monthly Leachate Chemistry – Hartland Valve Chamber – 2009/10
5. Quarterly Leachate Chemistry – Trace Organics– 2009/10
6. Monthly Leachate Chemistry– Phase 2 Cleanout – 2009/10
7. Monthly Leachate Chemistry– North Purge Well – 2009/10
8. Monthly Leachate Chemistry– Controlled Waste Ditch – 2009/10
9. Monthly Leachate Chemistry– Markham Valve Chamber – 2009/10
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(April 2009 to March 2010)
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C. Hartland Climate Data
1. Daily Rainfall Data Collected from the Hartland Weather Station – 1997 to 2010
2. Monthly Rainfall Data Collected from the Hartland Weather Station – 1997 to 2010
D. Leachate Flow Data
E. Hartland Landfill Site Plan
F. Hartland Landfill Leachate Pipeline Plan
G. Results of Statistical Analysis 2009/10
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(April 2009 to March 2010)
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1. Introduction
Hartland landfill is located at the end of Hartland Avenue approximately 14 km north of Victoria (Figure 1-1). Filling
with waste commenced at the site in the 1950s. The site was owned and operated by a private company until 1975
when the property was purchased by the Capital Regional District (CRD). The landfill is currently owned and
operated by the CRD and is the primary solid waste disposal site for the 13 member municipalities of the Capital
Region.
The CRD initiated a ground and surface water monitoring program for the landfill in 1983. Gartner Lee Limited (GLL)
was retained in February 1987 to interpret the monitoring data and provide hydrogeological input into the design and
operation of the landfill. A comprehensive report titled "Hartland Landfill, 1986-1987 Hydrogeological Monitoring
Report" (GLL, 1987) was issued, based on an initial review of monitoring data and the results of a drilling and
hydrogeological testing program carried out during 1987. Annual monitoring reports have been prepared and issued
by Gartner Lee and AECOM since 1988. A summary of data collected between 1983 and 1995 is provided in the
“1995 Hartland Landfill Monitoring Report”. Since that time, annual reports have presented data summaries for the
reporting year and evaluated historic data trends at key locations. The present Hartland Monitoring Program is part
of an "Operating Plan" for the site that is required and approved by the BC Ministry of Environment.
The Hartland landfill site is divided into two distinct areas referred to as Phase 1 and Phase 2. Initially, waste was
deposited in Phase 1, which reached its capacity in 1996. Capping of Phase 1 was completed during the summer of
1997 and Phase 2 is currently receiving waste. Filling of Phase 2 Cell 1 was completed in 2004. During the summer
of 2004, the west face of Phase 2 Cell 1 was capped with a geomembrane to reduce passive gas venting and
provide an internal leachate collection system for future development of Phase 2 Cell 2. This area is referred to as
the West Face closure. Leachate and surface runoff from the active landfill areas are directed to two leachate
lagoons at the north end of the landfill. The water from these lagoons is then transported by a pipeline to the
Northwest Trunk sewer system and ultimately, the Macaulay Point deep ocean outfall. Leachate discharge to sewer
is authorized by a permit issued by the CRD Regional Source Control Program and is subject to the CRD Sewer Use
Bylaw.
Diversion of clean surface water runoff is important to minimize potential inflow to the leachate collection system and
to maintain natural baseflow in existing creeks. Clean surface water runoff from the eastern slopes of Mt. Work is
intercepted in lined diversion ditches located west of Phase 2 and directed off-site. Precipitation falling on the
capped area of Phase 1 is directed to a lined sedimentation pond at the north toe of Phase 1 and then discharged
into a wetland that eventually connects to Heal Creek at the north end of the landfill. The surface water sampling
program routinely tests water quality at property boundary stations.
17.
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Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
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The CRD ceased operation of a yard waste site at the Hartland North Pad on January 31, 2006 that was formerly
used to store, grind and sell yard waste material. All ground yard waste was removed from the Hartland North Pad
by March 15, 2006. Since July 2006, the Hartland North Pad has been used for aggregate stockpiling. Surface water
from this site generally flows to the northwest into Durrance Lake, which connects with Heal Creek via Durrance
Creek. Another drainage flows southeast parallel to Willis Point Road, connecting directly to Heal Creek. Surface
and groundwater monitoring has been conducted in the vicinity of the yard waste composting site (Hartland North
Pad) since 1994.
This 2009/10 monitoring report presents our interpretation of water quality results and groundwater flow conditions
to:
assess the potential impact of landfill leachate and operational activities on groundwater and surface water
quality;
evaluate the effectiveness of the leachate containment and collection systems; and
determine if leachate flow and leachate quality are changing over time.
Portions of the text contained in this document were extracted from previous reports.
19. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
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2. Site Description
2.1 Physiography
Hartland landfill is located in the Tod Creek watershed, in the bedrock highlands of the Gowland Range northwest of
Victoria. The terrain is moderately rugged with relief of up to 446 m in the area. Undeveloped CRD property (about
320 hectares in total) lies to the west and south of the landfill site. Mount Work Regional Park lies to the west and
the Department of National Defence rifle range to the north. Private residential properties exist to the east and
southeast of the landfill.
The landfill is situated in a north-south trending bedrock saddle. Mount Work lies to the west of the landfill and a bedrock
ridge lies to the east. The crest of the landfill forms a drainage divide between the Heal Creek drainage basin to the north
and the Killarney Creek drainage basin to the south.
2.2 Geology
The bedrock geology in the area surrounding the landfill mainly comprises Wark Diorite Gneiss with Colquitz Gneiss
outcropping in the northern and eastern margins of the landfill site. The Wark Diorite Gneiss is dark green to black in
colour. It is competent, except locally in shear zones, where it has been chloritized and weathered into soft, sand size
grains and clay. Discontinuities, including joints, shear zones and altered veins have been observed on the bedrock
outcrops.
A thin veneer of glacial till composed of silty, gravelly sand, with interspersed cobbles and boulders mantles the bedrock in
areas of gentle slopes and in valley bottoms. Fluvial deposits consisting of well sorted sands and gravels are also present
in localized bedrock depressions and channels.
2.3 Climate
The climate of this area is classified as "cool Mediterranean". Long-term (1971-2000) average climatic data is available for
the Victoria International Airport Climatological Station located approximately 9 km from the landfill. Average annual
temperature is 9.7ºC and mean monthly values range from a low of 3.8ºC in January to a high of 16.4ºC in July. Mean
annual precipitation is 883.3 mm.
Water balance calculations presented previously (GLL, March 1991a) indicated an annual water surplus of 723 mm based
on long term historical data (1951 to 1980). The surplus occurs primarily in the cool, wet winter months (November,
December and January) with water deficit conditions occurring in the warm, dry summer months (May, June and July).
In 1994, the CRD established a climate station (Victoria Hartland CS) at the landfill office. Both manual and automatic
readings of precipitation are recorded and the data is provided to Environment Canada on a daily basis. The 2009/10 daily
precipitation measurements are provided in Appendix C.
The precipitation measured at Hartland Landfill for April 2009 to March 2010 was 1,157.3 mm, which is greater than the
30 year average of 883.3 mm/yr reported for Victoria International Airport. A study completed by Golder (January 2010)
found that the precipitation data collected at the Victoria International Airport did not accurately reflect precipitation at
Hartland landfill, and underestimated it by approximately 25%. In addition, CRD recognized that there were problems with
the equipment and location of the original weather station. While annual fluctuation may account for some of the
difference, the majority of the difference is likely the result of a malfunctioning precipitation gauge. The Hartland climate
station was replaced in 2009/10 with new equipment at a location on top of Phase 1.The station is now regularly
maintained to ensure accurate data collection. The new weather station records temperature, precipitation, wind direction,
wind speed, barometric pressure and relative humidity directly to CRD’s SCADA system.
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Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
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3. Methodology
3.1 Field Techniques
Sampling locations are shown on Figure 5-1. Boreholes and monitors are identified using a standard system
adopted by the CRD consisting of three numbers (e.g., 02-02-01). The first number refers to the site, the second to
the borehole at that site (there may be more than one) and the third number refers to the monitor in that borehole
(there may be two or three at different depths in older installations). If the third number is a zero it indicates an open
borehole where no PVC monitoring well has been installed. Several leachate purge wells have been installed at
Hartland. Each purge well is designated with a “P” in front of the purge well number (e.g., P1).
Monitor construction details including location coordinates and elevations are summarized in Appendix A.1.
Appendix A.1 also lists the status of all the groundwater monitors at the site together with comments describing any
problems associated with each monitor, as described by CRD staff. Monitors are categorized as active (fully
functioning) or inactive (non-functioning or destroyed). In 2009/10 there were 118 active groundwater monitors at
58 locations in the vicinity of Hartland landfill. There were also 14 landfill gas wells that were regularly used to
measure leachate levels in Phase 1 during 2009/10.
The methods used to develop and sample each monitor are indicated in Appendix A.2. A variety of techniques are
used depending on the depth of the monitor, the water level elevation in the monitor and the permeability of the
surrounding geologic formation. Where possible, check valve pumps are used to avoid aerating the groundwater,
which can potentially affect water chemistry. A number of dedicated submersible pumps have been installed by CRD
in the deeper monitors and open boreholes at the landfill to facilitate more efficient sampling. The use of these
pumps has resulted in improved data quality. CRD is in the process of reviewing its groundwater and surface water
sampling protocols as part of ongoing quality assurance and quality control measures, and updating them as
required.
The monitoring program at Hartland landfill commenced in 1983. In 2009/10, the program consisted of the following:
groundwater level measurements four times per year; and five times per year in selected wells;
continuous water level monitoring with pressure transducers at north end of Phase 2;
continuous water level monitoring with pressure transducers at the north and south purge well systems;
quarterly monitoring of wells near the property boundary and key locations to assess the effectiveness of
leachate containment;
semi-annual monitoring of stations with relatively stable long-term historical data;
annual sampling for 11 residential wells within a 2 km radius of the landfill;
four times per year sampling of non-boundary surface water stations;
six times per year sampling of all surface water stations at property boundary points Sw-S-4, Sw-N-5, Sw-N-16,
Sw-N-41-S-1, Sw-N-42-S-1 and other key locations Sw-S-3, Sw-S-12 and Sw-N-18;
quarterly testing of the leachate discharge for trace organic compounds; and
monthly testing of the leachate for conventional parameters and metals at the point of discharge and selected
locations within the leachate collection system.
As in previous years, CRD staff carried out surface water, groundwater and leachate sampling and groundwater
level measurements. Further information on the monitoring program field procedures is contained in the CRD
Monitoring Procedure Manual.
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Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
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3.2 Sample Analysis and Quality Assurance
In 2009/10, routine surface water, groundwater and domestic well water laboratory analyses were performed by
Maxxam Analytics in Vancouver. Leachate chemistry samples were analyzed by Cantest Laboratories and Maxxam
Analytics. Maxxam Analytics also analyzed leachate samples for trace organic compounds.
A quality assurance program to assess the validity of the chemical analysis results was implemented in 1990. This
has involved the submission of randomly selected field replicate samples and "reference" Victoria municipal water
samples to the laboratory for analysis. In addition, 15 surface water and 27 groundwater samples were submitted in
duplicate between April 2009 and March 2010. One landfill leachate collection system sample (Hartland Valve
Chamber) was submitted in triplicate during this same period for analysis of conventionals, organics, metals,
polycyclic aromatic hydrocarbons (PAH), phthalate esters, ketones, aromatics, phenols, ethers, nitrosamines,
alkanes, alkenes and other select organic parameters. One sample from each station in the leachate collection
system was also submitted in duplicate during the year for analysis of conventional parameters, organics and
metals. In this report, each set of replicates was taken from the same source and/or site, and under the same
conditions. In all cases, the field replicates were submitted ‘blind’ to the laboratory. At the Hartland Valve Chamber
point of compliance, Hartland Environmental Programs coordinates with the Marine Monitoring Program to evaluate
QA/QC on a quarterly basis. At this point, the coordinated QA/QC data is evaluated by CRD internally.
The submission of duplicate or triplicate samples provides an estimate of the total uncertainty associated with the
data. Total uncertainty is the variability (precision plus bias) associated with the sample collection and sample
analyses. An allowable upper limit on total uncertainty (or data quality objective) of 25% has been established by the
Ministry of Environment (MOE) as a ‘rule of thumb’ criteria for analytical precision on aqueous samples. Data
exceeding the 25% criteria should be viewed with caution.
3.2.1 Relative Percent Difference – Groundwater and Surface Water
The CRD has used a number of different statistical methods for checking the precision and accuracy of its
monitoring program. In 2005/06, the CRD started using the relative percent difference (RPD) method, as
recommended by MOE, which uses duplicate analyses to determine precision of the analytical results. This method
expresses percent of difference between two values as the ratio of their absolute difference to the average value of
the sample and the duplicate, expressed as a percent. CRD has historically used relative standard deviation (RSD)
to assess the precision and accuracy of leachate analyses. The RSD, which requires triplicate samples, is calculated
as the standard deviation of the analyses divided by the average of the results and is usually expressed as a
percent. To be consistent with the groundwater and surface water programs, CRD started assessing precision and
accuracy of leachate results using the RPD method on a quarterly basis starting in the summer of 2009.
The relative expression of precision is influenced by how close the analytical value is to the method detection limit
(MDL). The MDL is the level above which there is a high probability (e.g., >95%) that a substance can be detected.
However, there is a range of analytical concentrations just above the MDL where the precision is known to be poor.
This range is generally taken to be three times the MDL and is called the “limit of quantification”. Consequently, the
use of RPD should be limited to values that are over the limit of quantification. RPDs for parameter concentrations
between the MDL and the limit of quantification are often above 25% due to the lack of precision at those
concentrations.
22. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
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Tables 3-1 and 3-2 present the calculated RPDs for replicate groundwater and surface water samples collected near
the landfill. In all three tables, RPDs and RSDs were highlighted if they were above 25% and it was noted if the
parameter concentrations were below the limit of quantification.
Table 3-1 indicates the following for groundwater samples collected at the landfill in 2009/10:
RPDs for pH and nitrite did not exceed the maximum acceptable relative percent difference of 25%. However,
RPDs for conductivity, iron, manganese, ammonia, nitrate, sulphate and chloride exceeded 25% for 14 out of
243 analyses when concentrations were above the limit of quantification.
Overall, field replicates showed fair to good precision, with the exception of one sample from well 16-1-1
(chloride), one sample from well 19-2-1 (iron), one sample from 25-1-1 (iron), one sample in well 36-3-1 (iron,
and ammonia), one sample collected from well 39-2-1 (nitrate), one sample collected from well 51-1-1
(manganese), one sample collected from well 54-2-1 (iron), one sample collected from well 56-1-1 (manganese),
one sample collected from well 62-2-1 (manganese), one sample from well 71-1-1 (iron) and one sample
collected from well 71-2-1 (conductivity, iron, ammonia, nitrate and sulphate). These samples had RPDs ranging
from 26.4% to 162.5%. Other RPDs for the 2009/10 monitoring year were within the acceptable range, or had
concentrations below the limit of quantification. Sampling results from wells 36-3-1 (October 2009) and 71-2-1
(February 2010) revealed RPDs of greater than 25% for multiple parameters and should be interpreted with
caution. Based on the results of this analysis, the groundwater quality data appears to be acceptably precise.
QA/QC data should be reviewed immediately after receipt of the data from the laboratory such that corrective
actions can be made in the event of a systemic problem.
Table 3-2 indicates the following for surface water samples collected at the landfill in 2009/10:
RPDs for temperature, alkalinity, conductivity, nitrate, nitrite, pH, sulphate and total suspended solids did not
exceed the maximum acceptable relative percent difference of 25% for samples with concentrations greater than
the limit of quantification. RPDs for total iron, dissolved iron, total manganese, dissolved manganese, dissolved
organic carbon, ammonia, chloride and dissolved ortho-phosphate exceeded 25% for 13 out of 240 analyses
when concentrations were above the limit of quantification.
Overall, field replicates showed fair to good precision, with the exception of one sample from Sw-N-05 (dissolved
iron, dissolved manganese, dissolved organic carbon, chloride and dissolved ortho-phosphate), one sample
collected from Sw-N-08 (chloride and dissolved ortho-phosphate), one sample collected from Sw-N-09
(ammonia), one sample collected from Sw-N-15 (dissolved iron and dissolved ortho-phosphate), one sample
collected from Sw-N-41s6 (dissolved manganese and dissolved ortho-phosphate), one sample collected from
Sw-N-42s1 (dissolved ortho-phosphate), one sample collected from Sw-N-43 (total and dissolved iron), one
sample from Sw-N-CSs2 (dissolved iron and total manganese), one sample from Sw-S-03 (total suspended
solids), one sample from Sw-S-27 (ammonia) and one sample collected from Sw-S-52 (total manganese and
dissolved organic carbon). These duplicates exhibited RPDs ranging from 27.5% to 143.7% for each parameter.
Other RPDs for these samples were either within the acceptable range, or were calculated for parameters with
concentrations below the limit of quantification. With the exception of the samples discussed above, calculated
RPDs are considered to be acceptably precise for the purposes of this report. All sampling protocols should be
strictly adhered to in order to ensure the quality of the data is maintained.
23. Table 3-1. Ground Water Chemistry QA/QC - Relative Percent Difference
Maximum Acceptable Relative Percent Differenc 25% 25% 25% 25% 25% 25% 25% 25% 25%
Method Detection Limit (MDL) 1. 0.001 0.0001 0.005 0.005 0.02 0.5 0.5 0.1
Limit of Quantitation (3 x MDL) 3. 0.003 0.0002 0.015 0.015 0.06 1.5 1.5 0.3
Conductivity -
electrical
Iron Manganese
Nitrogen -
ammonia
Nitrogen - nitrite Nitrogen - nitrate Sulphate Chloride pH
Station Replicate Date Sampled Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Dissolved Comments
µS/cm mg/L mg/L mgN/L mgN/L mgN/L mg/L mg/L pH
Gw-04-3-1 RPD 2009 Nov 25 0.7% na na na na 0.0% 8.0% 2.9% 1.3%
FR1 2009 Nov 25 534. < 0.005 < 0.001 < 0.005 < 0.005 0.04 39. 35. 7.8
FR2 2009 Nov 25 538. < 0.005 < 0.001 < 0.005 < 0.005 0.04 36. 34. 7.9 ---
Gw-16-1-1 RPD 2010 Feb 19 0.0% na na na na 4.4% 3.4% 36.6% a 1.3%
FR1 2010 Feb 19 311. < 0.005 < 0.001 0.021 < 0.005 0.22 29. 4.2 7.6
FR2 2010 Feb 19 311. < 0.005 < 0.001 < 0.005 < 0.005 0.23 30. 2.9 7.7 ---
Gw-17-1-3 RPD 2010 Feb 23 0.0% 7.7% 8.0% na na 0.0% 2.2% 15.1% 1.4%
FR1 2010 Feb 23 414. 0.025 0.012 < 0.005 < 0.005 0.47 46. 6.4 7.2
Very brown purge water at 5L, then light brown/grey. No
odour.Filtered clear and did not clog.
FR2 2010 Feb 23 414. 0.027 0.013 < 0.005 < 0.005 0.47 45. 5.5 7.3 ---
Gw-18-2-2 RPD 2009 Jul 16 2.7% na 0.0% na na 0.0% 0.0% 4.7% 1.3%
FR1 2009 Jul 16 370. < 0.005 0.001 < 0.005 < 0.005 0.12 17. 4.2 7.9
FR2 2009 Jul 16 360. < 0.005 0.001 < 0.005 < 0.005 0.12 17. 4.4 7.8 ---
Gw-19-2-1 RPD 2009 Sep 28 0.2% 84.4% a 24.7% na na na 7.2% 0.0% 2.7%
FR1 2009 Sep 28 510. 0.032 0.263 < 0.005 < 0.005 < 0.02 80. 10. 7.3
FR2 2009 Sep 28 509. 0.013 0.337 < 0.005 < 0.005 < 0.02 86. 10. 7.5 ---
Gw-20-1-1 RPD 2010 Feb 24 0.0% 8.7% 0.0% na na na 15.4% 2.0% 1.2%
FR1 2010 Feb 24 186. 0.024 0.004 < 0.005 < 0.005 < 0.02 14. 5. 8.1
FR2 2010 Feb 24 186. 0.022 0.004 0.012 < 0.005 < 0.02 12. 4.9 8.2 ---
Gw-21-1-2 RPD 2009 Jul 21 0.0% 0.0% 1.2% 2.9% na na 0.0% 0.0% 1.3%
FR1 2009 Jul 21 600. 1.58 2.46 7.1 < 0.005 < 0.02 23. 45. 7.6
FR2 2009 Jul 21 600. 1.58 2.43 6.9 < 0.005 < 0.02 23. 45. 7.5 ---
Gw-25-1-1 RPD 2010 Feb 26 0.6% 41.4% a 11.0% na na 13.3% 3.3% 1.6% 0.0%
FR1 2010 Feb 26 472. 0.14 0.096 < 0.005 < 0.005 0.07 59. 6.5 8.1
FR2 2010 Feb 26 475. 0.092 0.086 < 0.005 < 0.005 0.08 61. 6.4 8.1 ---
Gw-29-1-2 RPD 2009 Jul 29 4.3% 24.2% 15.9% na na na 5.0% 6.2% 0.0%
FR1 2009 Jul 29 470. 0.297 0.034 < 0.005 < 0.005 < 0.02 39. 50. 7.7
FR2 2009 Jul 29 450. 0.233 0.029 < 0.005 < 0.005 < 0.02 41. 47. 7.7 ---
Gw-31-1-1 RPD 2009 Dec 04 1.3% na 8.7% na na 0.0% 0.0% 1.5% 2.6%
FR1 2009 Dec 04 318. < 0.005 0.011 < 0.005 < 0.005 0.13 11. 6.8 7.7
FR2 2009 Dec 04 322. < 0.005 0.012 < 0.005 < 0.005 0.13 11. 6.9 7.9 ---
Gw-36-3-1 RPD 2009 Oct 06 2.3% 58.3% a 5.3% 51.4% a 66.7% b 0.0% 0.0% 3.3% 2.6%
FR1 2009 Oct 06 1340. 0.017 0.0116 0.013 0.005 1.46 130. 31. 7.6
FR2 2009 Oct 06 1310. 0.031 0.011 0.022 0.01 1.46 130. 30. 7.8 ---
Gw-37-3-1 RPD 2009 Dec 01 19.7% 2.4% 3.0% 0.5% na na 5.3% 1.2% 0.0%
FR1 2009 Dec 01 614. 1.63 0.426 0.815 < 0.005 < 0.02 58. 8.1 7.6
FR2 2009 Dec 01 504. 1.67 0.439 0.819 < 0.005 < 0.02 55. 8.2 7.6 ---
Gw-39-2-1 RPD 2009 Jul 22 0.0% 0.0% 3.4% 5.5% na 28.6% a 0.0% 7.1% 3.8%
FR1 2009 Jul 22 330. 0.006 0.03 0.113 < 0.005 0.03 21. 4.1 8.1
FR2 2009 Jul 22 330. 0.006 0.029 0.107 < 0.005 0.04 21. 4.4 7.8 ---
Gw-40-1-1 RPD 2009 Dec 01 0.0% 0.0% 0.7% 1.3% 1.4% 2.2% 0.0% 2.2% 0.0%
FR1 2009 Dec 01 1040. 0.01 1.36 7.01 0.285 4.7 85. 47. 7.8
FR2 2009 Dec 01 1040. 0.01 1.37 6.92 0.289 4.6 85. 46. 7.8 ---
Gw-42-1-1 RPD 2010 Mar 02 0.0% 8.8% 0.7% 5.1% na na 0.0% 0.0% 2.6%
FR1 2010 Mar 02 506. 0.691 0.134 0.06 < 0.005 < 0.02 35. 19. 7.5
FR2 2010 Mar 02 506. 0.633 0.133 0.057 < 0.005 < 0.02 35. 19. 7.7 ---
Gw-51-1-1 RPD 2009 Sep 30 3.1% na 85.7% a na na 19.6% 3.6% 8.7% 5.1%
FR1 2009 Sep 30 356. < 0.005 0.004 < 0.005 < 0.005 0.28 28. 12. 7.6
FR2 2009 Sep 30 345. 0.006 0.01 < 0.005 < 0.005 0.23 27. 11. 8. ---
Gw-54-2-1 RPD 2009 Sep 24 0.0% 40.0% a 3.5% na na na 0.0% 1.2% 0.0%
FR1 2009 Sep 24 524. 0.012 0.0262 < 0.005 < 0.005 < 0.02 28. 8.7 8.
FR2 2009 Sep 24 524. 0.008 0.0253 < 0.005 < 0.005 < 0.02 28. 8.6 8. ---
Gw-56-1-1 RPD 2009 Oct 09 0.9% 4.7% 72.0% a na na na 3.8% 8.7% 2.5%
FR1 2009 Oct 09 452. 0.022 0.017 0.006 0.005 < 0.02 53. 12. 7.8
FR2 2009 Oct 09 456. 0.021 0.008 < 0.005 < 0.005 < 0.02 51. 11. 8. ---
Gw-58-1-0 RPD 2009 Jul 31 0.0% 24.6% 1.2% 9.1% 2.7% 17.8% 1.2% 4.8% 0.0% Yellow, amber colour and slightly foamy
FR1 2009 Jul 31 5300. 0.83 6.53 49.3 0.144 9.8 85. 820. 7.2 Yellow, amber colour and slightly foamy
FR2 2009 Jul 31 5300. 0.648 6.45 54. 0.148 8.2 84. 860. 7.2 ---
Gw-62-2-1 RPD 2009 Oct 09 0.0% 15.4% 26.4% a 14.3% na 0.0% 0.0% 0.0% 3.8%
Footvalve & tube clogged with clay (light brown like
bentonite). Replaced footvalve &removed 6cm of tubing.
Water very slightly light grey-brown. Sample filtered with
no problem.
FR1 2009 Oct 09 300. 0.014 0.0951 0.013 < 0.005 0.08 12. 4.9 8.1
FR2 2009 Oct 09 300. 0.012 0.124 0.015 < 0.005 0.08 12. 4.9 7.8 ---
Gw-63-2-1 RPD 2010 Feb 25 0.9% na na 9.5% na na 7.4% 2.0% 6.1%
FR1 2010 Feb 25 331. < 0.005 < 0.001 0.01 < 0.005 < 0.02 13. 4.9 7.9
FR2 2010 Feb 25 328. < 0.005 < 0.001 0.011 < 0.005 < 0.02 14. 5. 8.4 ---
Gw-71-1-1 RPD 2010 Feb 16 0.0% 78.3% a 4.1% na na na 1.5% 1.3% 0.0%
FR1 2010 Feb 16 478. 0.016 0.024 < 0.005 < 0.005 < 0.02 66. 7.7 8.
FR2 2010 Feb 16 478. 0.007 0.025 0.01 < 0.005 < 0.02 65. 7.8 8. ---
Gw-71-2-1 RPD 2010 Feb 16 40.8% a 103.4% a na 122.0% b na 162.5% b 84.9% a 9.5% 3.9%
FR1 2010 Feb 16 463 0.022 0.024 0.008 < 0.005 0.03 24 9.9 7.9
FR2 2010 Feb 16 306 0.007 < 0.001 0.033 < 0.005 0.29 9.7 9 7.6
Gw-73-1-1 RPD 2009 Jul 28 2.0% 0.0% 6.7% na na na 0.0% 0.0% 0.0%
FR1 2009 Jul 28 510 0.004 0.0108 < 0.005 < 0.005 < 0.02 48 25 8 ---
FR2 2009 Jul 28 500 0.004 0.0101 0.008 < 0.005 0.03 48 25 8 Slightly turbid. Filtered clear.
Gw-76-3-1 RPD 2009 Sep 28 1.2% 7.2% 4.3% na na na 3.8% 0.0% 1.2%
FR1 2009 Sep 28 425 0.04 0.045 < 0.005 < 0.005 < 0.02 51 2.8 8 ---
FR2 2009 Sep 28 430 0.043 0.047 < 0.005 < 0.005 < 0.02 53 2.8 8.1
Gw-77-2-1 RPD 2009 Dec 08 0.2% 0.0% 3.1% na na na 0.0% 7.4% 0.0%
FR1 2009 Dec 08 402 0.011 0.033 < 0.005 < 0.005 < 0.02 29 5.2 8 ---
FR2 2009 Dec 08 403 0.011 0.032 0.018 < 0.005 < 0.02 29 5.6 8 Turbid, muddy brown-yellow colour Filtered clear
Gw-85-1-1 RPD 2009 Sep 22 3.0% 0.0% 0.0% 6.8% na 0.0% 9.1% 0.0% 1.3% Turbid, muddy brown-yellow colour Filtered clear
FR1 2009 Sep 22 990 0.005 1.43 3.2 < 0.005 4.7 69 170 7.7 ---
FR2 2009 Sep 22 1020 0.005 1.43 2.99 < 0.005 4.7 63 170 7.8 ---
Notes:
na - Not applicable, some replicates less than the detection limit.
a - Coefficient of variation greater than 25% and all replicates greater than the limit of quantitation.
b - Coefficient of variation greater than 25% with some replicates less than the limit of quantitation.
60158830_TBL-3-1b_2010-08-31_Groundwater - QC Replicates.xls:Replicates (2) Page 1 of 1
25. AECOM Capital Regional District Hartland Landfill Groundwater, Surface Water and
Leachate Monitoring Program Annual Final Report
(April 2009 to March 2010)
60158830_FN_RPT_2010 Dec 21 2010_Annual Rpt Sb.Docx 10
3.2.2 Relative Standard Deviation and Relative Percent Difference - Leachate
The relative standard deviation is a statistical measure of the precision of a data set. CRD used relative standard
deviation (RSD) to assess the precision of triplicate leachate analyses and the reliability of laboratory analyses until
April 2009. RSD is widely used in analytical chemistry to describe the precision of an assay. Table 3-3 presents
RSDs for triplicate samples collected from the Hartland flow detection valve chamber in April 2008. Starting in April
2009, RPDs have been used to assess the repeatability of analyses as described in Section 3.2.1 and shown in
Table 3-4.
Calculated RSD’s for five out of 174 parameters including fecal coliform, cadmium, chromium VI, acenapthene and
fluorine exceeded the maximum acceptable relative standard deviation of 25%, with RSDs of 96%, 29%, 35%, 43%
and 60%, respectively, where concentrations in all three replicates were above the limit of quantitation.
As shown in Table 3-4, calculated RPD’s for a total of 15 out of 273 analyses exceeded 25% for BOD, fecal coliform,
nitrite, total sulphide, naphthalene, phenanthrene, 2-methylnapthalene, fluoranthene, total high molecular weight
PAH’s, total uranium and total zinc concentrations on one out of three sampling dates when all concentrations were
above the limit of quantitation. Total PAH’s and total low molecular weight PAH’s exceeded RPD objectives on two
of three sampling dates. Overall, the RPD’s indicate that leachate quality data is acceptable for the current purposes.
PAH concentrations should be interpreted with caution on the June and November 2009 sampling dates. Efforts to
improve the repeatability of leachate analyses should be implemented in the future. This may involve the
development of a leachate sampling standard operating protocol and accompanying data quality objectives.
Leachate analyses that exceed RPD objectives should be reviewed with the laboratory immediately following receipt
of the analyses.
The remainder of parameters showed fair to good precision, with RSDs and RPDs generally below 25% for analytes
that were detected in all three samples. Given that landfill leachate is a complex analytical matrix, leachate analyses
are considered to be acceptably precise for the purposes of the monitoring program.
3.3 Summary
In summary, the 2009/10 quality assurance (QA) analysis indicates the water sampling and laboratory analysis have
produced reliable results. The QA sample analyses included 43 replicate groundwater and surface water samples
and the calculation of RPDs for 9 to 16 parameters per sample site, for a total of 483 RPDs. Of the 483 RPDs, there
were 27 RPDs that exceeded the 25% value where parameter concentrations were above the limit of quantification.
By comparison, 31 out of 451 RPD’s exceeded 25% in 2008/09 and only 11 of 451 RPDs exceeded the 25% limit in
2007/08. This indicates that although the analytical results are acceptable for this monitoring report, close attention
should be given to the groundwater and surface water sampling protocol to ensure high quality analytical data.
When parameter concentrations were above the limit of quantification, leachate RSDs were below the 25% limit for
all but five out of 190 parameters analyzed as part of the triplicate leachate analysis. Leachate RPD’s for 15 out of
273 analyses exceeded the 25% objective, where parameter concentrations were above the limit of quantitation in
2009/10. Therefore the laboratory analytical results for leachate are considered acceptable for the purposes of this
monitoring report.
Quality assurance laboratory analyses and laboratory precision should be evaluated monthly, and any discrepancies
should be resolved with the laboratory and sampling personnel within a month of receiving the laboratory results.
The appropriate notation should be added to the data files that explain the reason for the low precision and the steps
taken, if any, to improve the sampling or laboratory procedures.