2006 - 2007
CALIFORNIA CLIMATE
ACTION REGISTRY
GREENHOUSE GAS
INVENTORIES
VERIFICATION REPORT
Final (revised)
5528-B Hempstead Way
Springfield, VA 22151
703-813-6700 telephone
703-813-6729 facsimile
3622 Lyckan Parkway
Suite 2002
Durham, NC 27707
919-493-3144 telephone
919-493-3182 facsimile
Prepared for the:
San Lorenzo Valley Water District
13060 Highway 9
Boulder Creek, CA 95006-9119
Prepared by:
Stephen M. Roe
Juan Maldonado
Holly C. Lindquist
James H. Wilson
E.H. Pechan & Associates, Inc.
December 15, 2008
PECHAN
December 2008
CONTENTS
Page
ACRONYMS AND ABBREVIATIONS ........................................................................................ 1
VERIFICATION ACTIVITIES FOR THE 2006 & 2007 REPORTING YEARS ......................... 2
SCOPE OF THE VERIFICATION PROCESS ....................................................................... 2
STANDARD USED TO CALCULATE EMISSIONS ........................................................... 2
SCOPE OF VERIFICATION ACTIVITIES ........................................................................... 2
1. List of Identified Emission Sources and Organizational Boundaries....................... 3
1.1. Identified Sources ............................................................................................. 3
1.2. Organizational Boundaries ............................................................................... 4
2. Sampling Techniques and Risk Assessment Methods ............................................. 4
3. Comparison of SLVWD and Pechan Emission Estimates ....................................... 6
3.1. Indirect Emissions ............................................................................................ 6
3.2. Direct Emissions – Stationary Combustion ...................................................... 6
3.3. Direct Emissions – Fugitive Emissions ............................................................ 7
3.4 Direct Emissions – Mobile Source Combustion............................................. 10
3.5 Process Direct Emissions................................................................................ 11
3.6 Fugitive Direct Emissions .............................................................................. 11
3.7 De Minimis Sources ....................................................................................... 12
3.8 Material Misstatements................................................................................... 12
3.9 Immaterial Misstatements............................................................................... 12
3.10 General Evaluation of Compliance................................................................. 12
3.11 Verification Conclusion .................................................................................. 13
REFERENCES ............................................................................................................................ 14
TABLES
Table 1.
Table 2.
Table 3.
Table 4.
Table 5.
Table 6.
Final
Site Visits Conducted as Part of the CY 2006-2007 GHG Verification………….......…3
SLVWD’s CARROT Facilities for 2006 – 2007………………………..………………4
Assessment of Reporting Risk…………………………………………………..………5
Comparison of SLVWD’s 2006 Emission Estimates and Pechan’s Estimates…………8
Comparison of SLVWD’s 2007 Emission Estimates and Pechan’s Estimates ……...…9
Differences between SLVWD and Pechan Mobile Source Activity Data……………..11
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Greenhouse Gas Inventories Verification Report
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December 2008
ACRONYMS AND ABBREVIATIONS
BTU
CARROT
CH4
CO2
CO2e
CY
EF
GHG
GRP
HFC
IPCC
kWh
LGO
MMBTU
N2O
PFC
PG&E
Registry
SF6
SLVWD
t
WW
WWTP
Final
British Thermal Unit
Climate Action Registry Reporting On-line Tool
methane
carbon dioxide
carbon dioxide equivalents
calendar year
emission factor
greenhouse gas
The Registry’s General Reporting Protocol
hydrofluorocarbon
Intergovernmental Panel on Climate Change
kilowatt-hour
The Registry’s Local Government Operations Protocol
million British Thermal Units
nitrous oxide
perfluorocarbon
Pacific Gas & Electric
The California Climate Action Registry
sulfur hexafluoride
San Lorenzo Valley Water District
metric tons
wastewater
wastewater treatment plant
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VERIFICATION ACTIVITIES FOR THE 2006 & 2007
REPORTING YEARS
SCOPE OF THE VERIFICATION PROCESS
The San Lorenzo Valley Water District (SLVWD) contracted with E.H. Pechan & Associates,
Inc. (Pechan) to verify its greenhouse gas (GHG) emissions reported to the California Climate
Action Registry (the Registry) for the years 2006 and 2007. Calendar year 2006 was selected as
the base year for reporting to the Registry. These are the first years of GHG reporting by
SLVWD to the Registry, and include accounting for all six gases: carbon dioxide (CO2);
methane (CH4); nitrous oxide (N2O); hydrofluorocarbons (HFCs); perfluorocarbons (PFCs); and
sulfur hexafluoride (SF6). All of SLVWD’s GHG sources are located in California and emission
estimates have been submitted into the Registry’s Climate Action Registry Reporting On-line
Tool (CARROT). SLVWD selected reporting boundaries as management control - operation
criteria.
The San Lorenzo Valley Water District (SLVWD) is an independent special district supplying
water to approximately 18,000 people on the Central Coast. SLVWD utilizes both surface water
and ground water sources. SLVWD also owns and operates a wastewater treatment facility,
serving about 50 houses.
STANDARD USED TO CALCULATE EMISSIONS
For its combustion, process and electricity consumption GHG sources, SLVWD estimated its
emissions based on the methods outlined in the Registry’s General Reporting Protocol (GRP)
(CCAR, 2008a).
SCOPE OF VERIFICATION ACTIVITIES
The scope of this verification of calendar year (CY) 2006 and 2007 emissions covers all sources
of all six GHGs recognized by the Registry. The coverage includes all GHG sources over which
SLVWD maintains operational control. Verification activities for CY 2006-2007 included the
following:




Review of SLVWD’s CARROT submittal and comparison of the identified emission
sources to those expected by Pechan to emit GHGs;
Site visits to several SLVWD facilities to assess the coverage of GHG sources and gather
information underlying the 2006-2007 reporting (see Table 1 below);
Comparison of the underlying activity data used by SLVWD to other sources of data
[including Pacific Gas & Electric (PG&E); other internal SLVWD data sources]; and
Comparison of SLVWD-estimated GHG emission estimates to those developed by
Pechan.
The site visits were selected and conducted on the basis of their emissions potential in terms of
contribution to SLVWD’s total entity-level emissions. SLVWD’s CARROT reporting
aggregated GHG sources into 4 facilities:
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



December 2008
ADMIN - includes office space at 13060 Highway 9 in Boulder Creek and associated
vehicle;
OPS/DISTRIBUTION - includes a building at 13057 Highway 9 in Boulder Creek,
pumping stations, water storage, and associated vehicles and nonroad equipment;
OPS/SUPPLY & TREATMENT - includes well pumps, booster pumps, potable water
treatment facility, and the associated vehicles and nonroad equipment; and
WASTEWATER – covers the Bear Creek wastewater treatment plant (WWTP) and
associated wastewater (WW) lift pump.
As shown in Table 1, Pechan’s site visits covered at least one GHG source in each of the
reported “CARROT facilities” described in Section 1 below. However, each of the
individual assets operated by SLVWD that consume energy or otherwise emit GHGs were
not visited.
Table 1. Site Visits Conducted as Part of the CY 2006-2007 GHG Verification
Site
Administrative Building
(13060 Highway 9)
Operations Building
Bear Creek WWTP
Lyon Water Treatment Plant
Olympia Wells #2 and #3
GHG Emission Sources
Electricity consumption, gasoline vehicle,
vehicle refrigerants
Electricity consumption, propane combustion
(generator), onroad and nonroad diesel and
gasoline combustion, vehicle refrigerants
Electricity consumption, process N2O
Electricity consumption, diesel combustion
(generator)
Electricity consumption
In addition to the sources identified and initially reported by SLVWD, Pechan also identified the
following GHG sources: natural gas combustion in three buildings; vehicle air conditioners; and
nitrous oxide emissions at the Bear Creek WWTP. These sources are addressed under Section 3
below. Pechan verified that stationary air conditioning systems were using R-22 refrigerant, not
newer hydrofluorocarbon (HFC) refrigerants that would need to be reported to CARROT.
Pechan verified with SLVWD that no electrical equipment were owned (e.g. switchgear, circuit
breakers) that could contain components using SF6 as an insulator. Pechan verified with
SLVWD that no fire suppression systems using GHGs, such as PFCs, were in use.1
1.
List of Identified Emission Sources and Organizational Boundaries
1.1. Identified Sources
Table 2 provides a summary of indirect and direct sources identified by SLVWD as reported to
the Registry’s on-line reporting tool, CARROT, for the 2006 and 2007 reporting years.
Hereafter, we refer to these as “CARROT facilities” to distinguish them from either: actual sites
or buildings that SLVWD owns or operates; or individual sources of GHGs (e.g., a natural gas
1
Personal communication between Rick Rogers, SLVWD, Director of Operations, and S. Roe, Pechan.
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furnace, emergency generator). Reporting risk assessment methods and sampling techniques for
each of the CARROT facilities are described in Section 2.
Table 2. SLVWD’s CARROT Facilities for 2006 - 2007
Source
Type
Indirect
Direct
CARROT Facility
2006 tCO2e
2006
% of Total
2007 tCO2e
7.24
87.67
237.14
7.23
3.90
99.39
26.85
1.02
470.4
1.5%
18.6%
50.4%
1.5%
0.8%
21.1%
5.7%
0.2%
100.0%
7.70
96.30
321.78
5.72
3.51
110.92
23.53
0.94
570.4
Admin
OPS/Distribution
OPS/Supply & Treatment
Wastewater
Admin
OPS/Distribution
OPS/Supply & Treatment
Wastewater
Total
2007
% of Total
1.3%
16.9%
56.4%
1.0%
0.6%
19.4%
4.1%
0.2%
100.0%
SLVWD also generates solar electrical power to offset some of its electrical consumption.
Excess power is sold back to PG&E. Any additional power put back on the electrical grid is not
captured within SLVWD’s reporting, since it should be captured within PG&E’s delivered
electricity metric (which SLVWD uses to estimate its indirect emissions).
1.2. Organizational Boundaries
SLVWD based its organizational boundaries on management control using the operational
criteria outlined in the GRP (CCAR, 2008a). SLVWD demonstrated that it has operational
control over each of the sources identified in its CARROT reporting (e.g. third-party contractors
are not used to operate any of its facilities).
2.
Sampling Techniques and Risk Assessment Methods
As shown in Table 2, the primary contributors to 2006 and 2007 GHG emissions were indirect
emissions from electricity consumption and direct emissions from combustion of fuels. Based
on the reported 2006 emissions data, Pechan performed an assessment of reporting risk (i.e. risk
of reporting a material misstatement of emissions at the entity-level). Table 3 provides a
summary of this assessment. The data include the reported CY2006 GHG emissions for each
CARROT facility and source, and their contribution to the SLVWD 2006 total.
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Table 3. Assessment of Reporting Risk
NOTE: emissions of N2O and CH4 in this table listed without emission estimates are not necessarily zero; these were listed in the CARROT report as 0.00 metric tons, however the results
could have just rounded to 0.00 before application of the global warming potential. In any case, these sources would not have contributed significantly to the entity total. Emissions above
only include those identified in the initial SLVWD CARROT reporting. Additional sources identified by Pechan are not included.
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The reported emissions data are followed by a factor (potential deviation) that represents
Pechan’s assessment of the overall uncertainty in the emissions estimate based on both the
emission estimation method (e.g. emission factor) and the activity data (e.g. kilowatt-hours of
electricity). These estimates of uncertainty are based on Pechan’s professional judgment of the
quality in both the emission factor/other emission estimation method used and the activity data
used to estimate emissions.
The results indicate that for both the reported and projected emission estimates, indirect
emissions for electricity consumption (particularly for groundwater wells and booster pumps)
and vehicle fleet emissions are the primary contributors to entity-level emissions. Hence, Pechan
focused attention on these sources during this CY2006-2007 verification.
3.
Comparison of SLVWD and Pechan Emission Estimates
A comparison of the SLVWD’s 2006 and 2007 GHG emission estimates to those developed by
Pechan is provided in Tables 4 and 5 below. From Table 4, the difference of total emissions
excluding de minimis sources at the entity-level for CY2006 is -13.7 tCO2e or -2.8 percent.
Much of this difference stems from a different approach in estimating liquid petroleum gas
(LPG) consumption by generators and immaterial discrepancies found in fuel usage activity data.
In Table 5 covering CY2007, the difference was less than 1 tCO2e and less than 1 percent. In the
subsections that follow, details of the assessment of each source (CARROT facility) are
provided.
3.1. Indirect Emissions
Indirect emissions are limited to those associated with electricity consumption. Electricity
consumption was reported under all four CARROT facilities (Admin, OPS/Distribution,
OPS/Supply and Treatment, and Wastewater).
Pechan obtained 2006 and 2007 billing data by meter from the electricity provider PG&E
(Roderos, 2008). For 2006, Pechan’s estimate for the total indirect emissions associated with
electricity consumption was 339 metric tons, the same as SLVWD’s estimate. For 2007,
Pechan’s estimate for the total indirect emissions associated with electricity consumption was
432 metric tons, the same as SLVWD’s estimate.
3.2. Direct Emissions – Stationary Combustion
Direct stationary emissions in Tables 4 and 5 represent department aggregate amounts of diesel,
gasoline, liquid petroleum gas, and natural gas fuel combustion. A description of each fuel type
follows below.
Diesel Combustion
Stationary diesel combustion was associated with the operation of generators. For 2006 and
2007, SLVWD did not have a direct means of measuring the volume of diesel dispensed to each
generator. In order to estimate activity data for this source, Pechan adopted the SLVWD method
of estimating diesel consumption from MBRAPCD reports for generators GT-670, GT-740, GE00290. Pechan recommends direct measurements of fuel dispensed to generators since values on
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MBRAPCD reports do not represent calendar year (January to December) consumption.
Additional diesel combustion was identified in GASFY2 as “can” diesel and was attributed to
generator GE-00971. Pechan agrees with the choice of emission factors selected from the GRP
(CCAR, 2008a) by SLVWD.
3.3. Direct Emissions – Fugitive Emissions
Because fugitive emissions from refrigerant losses are typically negligible when compared with
total entity emissions, the GRP prescribes the use of a screening method that helps determine
whether fugitive emissions are insignificant or warrant a more comprehensive review.
The screening method assumes a refrigerant charge of 1 kg of HFC-134a for large vehicles and
0.5 kg of the same compound for small vehicles. The refrigerant loss rate for both vehicle types
is assumed to be 35%. In 2006, SLVWD operated 19 vehicles, of which 17 were estimated by
Pechan to be equipped with air conditioning units. Of these 17 vehicles, 2 were small and 15
were large in size. In 2007, SLVWD operated 21 vehicles, of which 18 were estimated to be
equipped with air conditioning units. Of these 17 vehicles, 2 were small and 16 were large in
size.
The screening determined that direct fugitive emissions from vehicle air conditioning units were
not significant, and therefore, could be categorized as de minimis emissions.
Gasoline Combustion
GASFY identifies gasoline used for fueling stationary equipment (e.g. chain saws, air
compressors) as “can” gasoline. No issues were found in SLVWD’s choice of emission factors
from the GRP (CCAR, 2008a).
Liquid Petroleum Gas (LPG) Combustion
Stationary LPG combustion was associated with the operation of generators. According to the
GRP (CCAR, 2008a), the preferred method to determine annual consumption of fuels involves
having fuel inventory data for the beginning and the end of the year in addition to individual
purchases within the year (Equation III.8a). Unfortunately, SLVWD had no inventory
information. In lieu of beginning and end inventory values, SLVWD assumed these values to be
equivalent to the closest LPG purchase transactions to January 1st, and December 31st of each
reporting year. For that reason, and in order to avoid double-counting, Pechan opted to include
only those transactions within a reporting year. To reduce uncertainty associated with these
sources, Pechan recommends maintaining beginning and end of year inventory records. This
difference in approach accounted for the difference in direct stationary emissions totals in Tables
4 and 5.
2
GASFY is a fuel consumption summary spreadsheet maintained by SLVWD’s accounting department.
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Table 4. Comparison of SLVWD’s 2006 Emission Estimates
and Pechan’s Estimates
2006 CO2e Emissions (metric tons)
SLVWD
Estimate
Indirect Emissions
Admin (electricity)
7.2
OPS/Distribution (electricity)
87.7
OPS/Supply & Treatment (electricity)
237.1
Wastewater (electricity)
7.2
Indirect Subtotal
339.2
Stationary Direct Emissions
Admin (natural gas)
1.0
OPS/Distribution
6.7
OPS/Supply & Treatment
4.6
Wastewater (Generator)
0.7
Mobile Direct Emissions
Admin
2.9
OPS/Distribution
93.1
OPS/Supply & Treatment
22.2
Process Direct Emissions
Wastewater (Bear Creek Septic System)
0.3
Fugitive Direct Emissions
Vehicle Fleet – Fugitive A/C Refrigerants
0.0
Direct Subtotal
131.5
de minimis emissions
Booster pumps OPS/Dist
0.3
Building ADMIN
0.0
Groundwater wells, buildings SUP/TR
0.7
Vehicle Fleet ADMIN
0.0
Generator – Admin
0.3
Generator OPS/Dist
0.0
Generators – Supply & Treatment
0.0
de minimis Subtotal
1.3
Totals
472.0
Source (CARROT Facility ID)
Pechan
Estimate
Difference
7.2
87.7
237.1
7.2
339.2
0
0
0
0
0
1.0
6.1
4.6
0.8
0
0.6
0
-0.1
2.4
101.7
21.0
0.5
-8.6
1.2
0.3
0
7.3
145.2
-7.3
-13.7
0.3
0.0
0.7
0.1
0.6
0.0
0.0
1.7
486.1
0
0
0
-0.1
-0.3
0
0
-0.4
-14.1
Totals (excluding de minimis sources)
470.7
484.4
Difference Between SLVWD and Pechan Estimates =
-13.7
-2.8%
NOTE: Totals may not add exactly due to rounding. Some totals and subtotal differ from CARROT report due to
adjusted emission categorization.
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Table 5. Comparison of SLVWD’s 2007 Emission Estimates
and Pechan’s Estimates
2007 CO2e Emissions (metric tons)
SLVWD
Estimate
Indirect Emissions
Admin (electricity)
7.7
OPS/Distribution (electricity)
96.3
OPS/Supply & Treatment (electricity)
321.8
Wastewater (electricity)
5.7
Indirect Subtotal
431.5
Stationary Direct Emissions
Admin (natural gas)
2.3
OPS/Distribution
4.3
OPS/Supply & Treatment
3.0
Wastewater (Generator)
0.6
Mobile Direct Emissions
Admin
1.2
OPS/Distribution
106.6
OPS/Supply & Treatment
20.5
Process Direct Emissions
Wastewater (Bear Creek Septic System)
0.3
Fugitive Direct Emissions
0.0
Vehicle Fleet – Fugitive A/C Refrigerants
Direct Subtotal
138.8
de minimis emissions
Booster pumps, buildings – OPS/Dist
0.3
Building - ADMIN
0.0
Groundwater wells, buildings - supply
0.9
Wastewater treatment plant
0.0
Vehicle Fleet-ADMIN
0.0
Vehicle Fleet-SUP/TRTMT
0.0
Generator – Admin
0.3
Generators – OPS/Distribution
1.8
Generators – Supply & Treatment
0.0
Generator – WSTWTRa
1.8
de minimis Subtotal
5.1
Totals
574.2
Source (CARROT Facility ID)
Pechan
Estimate
Difference
7.7
96.3
321.8
5.9
431.7
0.0
0.0
0.0
-0.2
-0.2
2.3
4.3
4.5
0.8
0.0
0.0
-1.5
-0.2
1.1
98.3
18.6
0.1
8.3
1.9
0.3
0.0
7.7
137.9
-7.7
0.9
0.3
0.0
0.9
0.0
0.1
0.0
0.0
0.7
0.0
0.0
2.0
570.5
0.0
0.0
0.0
0.0
-0.1
0.0
0.3
1.1
0.0
1.8
3.1
3.8
569.6
0.7
Difference Between SLVWD and Pechan Estimates =
0.1%
Totals (excluding de minimis sources)
570.3
NOTE: Totals may not add exactly due to rounding. Some totals and subtotals differ from CARROT report due to
adjusted emission categorization.
a
These are just the CH4 and N2O emissions for the wastewater treatment plant generators. Pechan identified an error in
the calculation of these leading to a Pechan estimate of less than 0.1 tCO2e for CH4 and N2O.
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December 2008
Natural Gas Combustion
Pechan estimated these emissions to be 5.9 metric tons in 2006 and 6.6 metric tons in 2007 based
on billing data provided by PG&E (Roderos, 2008). These totals matched SLVWD’s emissions
estimates. Additionally, SLVWD split this total by account number to reflect natural gas
combustion emissions by department (administration and operations/distribution).
3.4
Direct Emissions – Mobile Source Combustion
Direct mobile emissions in Tables 4 and 5 represent department aggregate amounts of diesel,
gasoline, and liquid petroleum gas fuel combustion. A description of each fuel type follows
below.
Gasoline & Diesel Combustion
The District has accounts with three local gas stations. According to SLVWD, when a driver
buys fuel, he uses the District’s account number to charge the fuel (one of the stations issues the
District a Quikstop credit card for each driver; the other two stations, Ben Lomond Gas and
Boulder Creek American Gas, have District charge accounts that the drivers use). When gas is
charged to the District, these gas stations will pump gas only into District vehicles. When the
drivers get the charge receipts, the receipts are stamped with a red District stamp, where the
driver writes his name, employee number and truck number. The drivers turn in their receipts
every day. The Accounting Department records the fuel used by each truck and then forwards
the receipts to Accounts Payable.
Pechan conducted a verification of the activity data associated with gasoline and diesel purchase
transactions. Due to the large number of transactions consisting of individual fuel purchases per
day and per vehicle, Pechan sampled 20% of all transactions according to the guidelines of
General Verification Protocol, Section 3.4 (CCAR, 2008b). Complete sets of 2006 and 2007
records for vehicles U155, U311, U339, and D650 were selected because they had the largest
fuel consumption values and were representative of both gasoline and diesel fueled vehicles.
Pechan’s analysis of the activity data is shown in Table 6.
All fuel consumption was adjusted to reflect the findings shown in Table 6. Consequently,
carbon dioxide emissions were reduced by 4.8% in 2006 and increased by 10.1% in 2007, since
estimates were based on fuel consumption.
Methane and nitrous oxide emission were calculated based on mileage in accordance to the GRP,
Chapter 7.2 (CCAR, 2008a). Pechan corroborated mileage activity data and methods and agreed
with SLVWD emissions estimates. Upon aggregating methane and nitrous oxide with carbon
dioxide emissions into single department mobile combustion sources, uncertainty associated with
carbon dioxide emissions was reduced. Hence, the overall CO2e estimates by Pechan shown in
Tables 4 and 5 are not as large as the 4.8% and 10.1% for carbon dioxide described in Table 6.
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Table 6. Differences between SLVWD and Pechan Mobile Source Activity Data
U155
U311
U339
D650
All
2006 Difference
2.7%
-1.1%
-0.5%
-6.0%
-4.8%
2007 Difference
4.7%
1.0%
4.4%
0.0%
10.1%
Finally, a few data transfer errors were observed when comparing GASFY and SLVWD
emission calculation spreadsheets. Data transfer reporting errors also contributed to the
difference in emission estimates between Pechan and SLVWD.
Liquid Petroleum Gas (LPG) Combustion
The operation of vehicle “740 Toyota forklift” accounted for all mobile combustion resulting
from LPG combustion. Pechan found no issues in the selection of methods or results associated
with this source.
3.5
Process Direct Emissions
Bear Creek Septic System
The only process emissions for SLVWD are nitrous oxide emissions associated with the Bear
Creek Septic System, which serves about 50 households. This system has a
nitrification/denitrification system, and thus would be expected to emit some N2O during
removal of nitrates from the wastewater. While methods for estimating N2O from the specific
type of system used by SLVWD are not available, the method for centralized wastewater
treatment systems with nitrification/denitrification systems was used in order to generate an
estimate to gauge the importance of this source. The method (Equation 10.7) comes from the
Registry’s Local Government Operations Protocol (Registry, 2008c).
Pechan concurs with the use of the Registry’s Local Government Operations (LGO) Protocol
(Registry, 2008c) to estimate nitrous oxide emissions. The LGO’s Equation 10.7 best
approximates the conditions at SCVWD. The emission factor for Equation 10.7 is 7
grams/person-year. Hence, an annual CO2e estimate, assuming an average of 3 people per
household is: 50 HH x 3 people/HH x 7 gN2O/person x 1 t/106 gN2O x 310 (GWP) = 0.33
tCO2e/yr.
3.6
Fugitive Direct Emissions
Fugitive Vehicle Refrigerant Emissions
The screening method for mobile refrigerant fugitives in the GRP was used to show that HFC
emissions are at de minimis levels. This is shown in Tables 4 and 5. In both years, emissions
from vehicle refrigerant fugitives are expected to be less than 2% of entity-level emissions.
Stationary Refrigeration and Air Conditioning
Pechan identified no air conditioning or refrigeration systems that are using HFCs.
Fire Suppression Systems
As noted under Section 1.1 above, no fire suppression systems were identified that use HFCs or
PFCs.
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3.7
December 2008
De Minimis Sources
Pechan’s estimates for de minimis sources agree with SLVWD’s estimates, except for the
following:
 2006 & 2007 Vehicle fleet ADMIN methane and nitrous oxide emissions differ due to
fuel activity issues described in Section 3.4.
 2006 Generator-ADMIN as well as 2007 Generator emissions for the administration,
operations, and wastewater departments differ due to a difference in approach
quantifying LPG usage as described in Section 3.2; and
 2007 emissions reported as de minimis for N2O and CH4 (wastewater treatment
generators); Pechan identified an error in the spreadsheet calculation which results in
emission estimates of less than 0.1 tCO2e.
3.8
Material Misstatements
Pechan identified no material misstatements in SLVWD’s CARROT reporting for 2006 or for
2007.
3.9
Immaterial Misstatements
Pechan identified the following immaterial misstatements in SLVWD’s CARROT reporting for
2006 and 2007:




SLVWD did not include emissions of HFCs from vehicle air conditioners. Pechan’s
screening estimates indicate that these would be emitted at levels considered to be de
minimis; however, future reporting by SLVWD should include the identification of this
source as a de minimis source;
Pechan’s direct stationary combustion emissions estimates slightly differ from SLVWD’s
estimates due to a difference in approach in the quantification of LPG activity data as
described in Section 3.2; and
Pechan’s direct mobile combustion estimates differ from SLVWD’s estimates due to
discrepancies observed in fuel activity data as described in section 3.3; and
Note the issue under Section 3.7 above regarding the wastewater treatment plant
generator N2O and CH4 emissions. Once corrected, Pechan suggests that these be
reported along with CO2 not as de minimis in the future to avoid confusion by reviewers.
3.10 General Evaluation of Compliance
Based on our review of SLVWD’s 2006 and 2007 CARROT reporting, we conclude that it is in
compliance with the Registry’s General Reporting Protocol version 3.0. Pechan also has the
following additional recommendations to enhance SLVWD’s GHG management program:
1. Pechan recommends that SLVWD develop an Inventory Management Plan that
documents the selection of organizational boundaries; identifies emission sources;
emission estimation procedures; and data collection and management;
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2. Pechan recommends the use of direct measurement to estimate diesel consumption in
generators; and
3. Pechan recommends maintaining beginning and end of year inventory records in addition
to fuel purchases for LPG consumption in generators.
3.11 Verification Conclusion
Pechan will verify that SLVWD has had its annual GHG emissions report covering the periods
January 1, 2006 to December 31, 2006 and January 1, 2007 to December 31, 2007 verified
according to the California Climate Action Registry’s GRP Verification Protocol version 3.0.
Pechan identified no material misstatements in SLVWD’s CY2006 and CY2007 GHG reporting
to the Registry. Pechan did not identify any other reporting issues that would cause noncompliance with GRP version 3.0.
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REFERENCES
CCAR, 2005. Appendix to the General Reporting Protocol: Power/Utility Reporting Protocol,
Reporting Entity-Wide Greenhouse Gas Emissions Produced by Electric Power Generators and
Electric Utilities, Version 1.0, April 2005.
CCAR, 2008a. General Reporting Protocol, Version 3.0, California Climate Action Registry,
April 2008.
CCAR, 2008b. General Verification Protocol, Version 3.0, California Climate Action Registry,
August 2008.
CCAR, 2008c. Local Government Operations Protocol, Version 1.0, California Climate Action
Registry, September 2008.
Roderos, 2008. Evelyn Roderos, Pacific Gas & Electric, personal communication with H.
Lindquist, Pechan, November 2008.
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