Questions about Canada’s seventh report to the Joint Convention ~ letter to IAEA from CCRCA

From: Concerned Citizens of Renfrew County and Area

To: Rafael Mariano Grossi

Director General

International Atomic Energy Agency

Date: May 31, 2021

We thank the IAEA for organizing the September 2019 Integrated Regulatory Review Service (IRRS) Mission to Canada.Recommendation R1 in the report of this Mission is that ““The Government should enhance the existing policy and establish the associated strategy to give effect to the principles stated in the Canadian Radioactive Waste Management Policy Framework.”  

This is a still work in progress, as illustrated by Canada’s Seventh National Report to the Joint Convention on the Safety of Spent Fuel Management and on the Safety of Radioactive Waste Management.  As appropriate, we would be grateful if you could forward this note to participants in the 7th review meeting of the Joint Convention.

Article 32 of the Joint Convention says:

2. This report shall also include…  (iv) an inventory of radioactive waste that is subject to this Convention that: (a) is being held in storage at radioactive waste management and nuclear fuel cycle facilities; (b) has been disposed of; or (c) has resulted from past practices. This inventory shall contain a description of the material and other appropriate information available, such as volume or mass, activity and specific radionuclides;

Canada’s 7th report says that data are “not available” (N/A) for activity and specific radionuclides in the Government of Canada’s waste at the Chalk River Laboratories (CRL).  This is where most federal radioactive waste is stored and is Canada’s only facility for commercial radioactive waste storage. CRL is managed by “Canadian Nuclear Laboratories”, a private company owned by a consortium of multinational engineering firms under a 2015 contract with Atomic Energy of Canada Limited (AECL).

Canada’s 7th report omits considerable data shown in Table B-2 (appended below) of AECL’s 2014 Comprehensive Preliminary Decommissioning Plan, as well as additional data listed as “available” but not shown in Table B-2.  

Table B-2 provides activity values of 1040 TBq beta/gamma, 2.1 TBq alpha, 1070 TBq tritium, and ~ 75 TBq unspecified for a portion of the Chalk River wastes.  Data gaps in Table B-2 include CRL’s  oldest Waste Management Area, WMA A, and one of its newest, WMA H, where the Shielded Modular Above-Ground Storage (SMAGS) facilities are found.  Despite the data gaps in Table B-2, the activity and radionuclide data found therein should be included in Table D.8 of Canada’s 7th report.  

Table B-2 also lists additional activity data as being “AVAILABLE” for certain CRL waste areas, including the WMA B circular concrete bunkers, rectangular concrete bunkers, and tile holes; the WMA C extension unlined trenches; the potentially contaminated equipment, materials and drummed liquids in WMA D; and the reprocessing wastes in the Thorium Pit from operation of the 233U extraction facility.  

These data should also be reported pursuant to Article 32 of the Joint Convention.

There are major differences between the waste volume data for CRL in Canada’s 7th report and in Table B-2.  Table B-2 shows a total volume of all waste types of 235,165 m3, with an additional 380,000 m3 of contaminated soils and slags.  These are far higher values than those in Table D.8 of Canada’s 7th report.  It gives a total of only 154,858 m3 of all waste types, and only 156,276 m3 of contaminated soils, at CRL. 

Canada’s 7th report also shows major unexplained changes in the inventory of federal radioactive waste relative to Canada’s 6th national report, The absence of adequate explanations for these changes calls into question the 7th report’s credibility.

Comparing data from Table D.8 (p. 48) in Canada’s 7th report to data in the 6th report (Table D.3, p. 27) for CRL, the reported volume of intermediate-level waste (ILW) decreased by 95% – from 19,648 to 1,050 m3.  

A footnote to Table D.8 says:

“Prior estimates were based on a conservative assumption that all waste stored within a structure that could contain ILW would be categorized as ILW until better characterization data became available. Between 2016 and 2019, retrieval and processing operations were conducted on selected legacy wastes in storage, and records were verified to extrapolate the current volumes.” 

Canadian Nuclear Laboratories (CNL), the operator of CRL, is not listed as a contributor to Canada’s 7th report.  Canada’s 7th report should identify the body that did the “better characterization” of ILW, provide details on how it was done, and specify quantities of ILW that were reclassified as low-level waste (LLW).   More generally, clarification is needed as to how the Government of Canada’s ILW and LLW are differentiated. 

The disappearance of 18,598 m3 of ILW at CRL can only be partly accounted for by a 12,873 m3 increase in LLW (comparing Table D.8 in Canada’s 7th report to Table D.3 in the 6th report).  

This apparent reclassification of federal ILW as LLW has implications for a proposed landfill at CRL, listed in section 3.0 of the 7th report as a “current priority”:

a near surface disposal facility (NSDF) for the disposal of up to 1,000,000 m3 of low-level radioactive waste (LLW) at CRL. Pending regulatory approval, the proposed disposal facility will be constructed, and the forecasted date of operations is 2024. 

Although this proposed “NSDF” facility is termed a “near surface disposal facility” in the 7th report, the final Environmental Impact Statement (EIS) for this facility says (p. 1-5) that it “would resemble a conventional landfill for municipal or industrial refuse, with measures to cover the waste.”

According to SSR-5, Disposal of Radioactive Waste, such a landfill facility would be suitable only for disposal of very low level radioactive waste (VLLW) – waste with low concentrations or quantities of radioactive content.  Plans to put LLW – and possibly ILW reclassified as LLW – in such an above-ground, landfill-type mound are a matter of concern.  Again, clarity is needed on how Canada’s wastes are classified.

Note that Canada’s 7th report does not provide data for wastes considered to be VLLW.

The final EIS indicates that CNL intends to put 134,000 m3 of packaged wastes in this proposed disposal facility (Table 3.3.1-1, p. 3-24). The final EIS (p. 3-23) and the NSDF Project Waste Acceptance Criteria (pages 12 and 24) identify as packages intermodal containers (e.g., 20-foot ISO containers), steel waste boxes (e.g., B-25 boxes), drums (e.g., 205-L drums), shielded waste packages, and disused sources.

These packages could contain a variety of long-lived and high-activity radionuclides, possibly not well characterized, and very likely unsuitable for landfill disposal.  

An NSDF Project Reference Inventory Report notes that there are data gaps “compared to what would be required for disposal assessment” of packaged wastes to be put in the facility.  This report describes assumptions, methods, use of scaling factors, qualitative assessments, etc. used to estimate activities of specific radionuclides in the packaged wastes at CRL.  These estimates do not appear in Canada’s 7th report.

Another major change in Canada’s 7th report relative to the 6th report is the 59% decrease in the reported volume of LLW in the form of “Contaminated soils” at Chalk River – from 382,842 m3 in 2017 (Table D.3) to 156,276 m3 in 2020 (Table D.8).  

No explanation is given for this decrease of 226,566 m3 in the reported volume of contaminated soils. The description in Canada’s 7th report of the sources of these contaminated soils — “Luggers, 205 L-steel drums, B-25 containers in SMAGS, sand trenches and above-ground stockpiles” — is identical to that found in the 6th report.

Canada’s reduced inventory of contaminated soils also has implications for wastes to be put in the proposed landfill.  The April 2017 draft EIS for this facility gave a volume figure of 370,000 m3 for “Soil and Soil‐like Waste” (p. 3-8) – similar to the figures of 380,000 m3 of contaminated soils and slags in WMA F found in Table B-2, and 382,842 m3 in the 6th report.  The final EIS has no figure for contaminated soils to be put into the facility – only a combined figure of 866,000 m3 for all types of non-packaged wastes.  

An explanation for the change in contaminated soil volume at CRL between Canada’s 6th and 7th reports is needed. 

Table D.12 and section 8.1 of Canada’s 7th report indicate that CNL was actively decommissioning various facilities (e.g., the waste water evaporator building, NRX delay tanks, NRX fuel bay,  NRX ancillary buildings, plutonium recovery laboratory, plutonium tower) at Chalk River during the April 1, 2017, to March 31, 2020 reporting period.  However, whereas the 6th report had separate tables for wastes from “normal operations” (Table D.3) and wastes from “decommissioning activities” (Table D.5), the latter table was omitted from Canada’s 7th report. 

An explanation is needed as to why a table describing wastes arising from decommissioning activities has been removed from Canada’s 7th report.

Table D.8 (p.49) in Canada’s 7th report has a row labeled “Decommissioning waste” for CRL.  The dates given for this row are January 1, 2005 to December 31, 2016.  This would seem to indicate that data for decommissioning waste for Chalk River in the 7th report were not updated from the 6th report, which shows the same time period.  

However, the two reports have greatly different volumes – 332 m3 ILW and 16,894 m3 LLW in the 7th report; compared to 125 m3 ILW and 2,876 m3 LLW in the 6th report. 

This inconsistency should be addressed.

Of particular concern is the absence of data on activity and specific radionuclides for the Government of Canada’s decommissioning wastes.  GSR Part 6, Decommissioning of Facilities, states that 

During the preparation and updating of the final decommissioning plan, the extent and type of radioactive material at the facility (e.g. activated and contaminated structures and components) shall be determined by means of a detailed characterization survey and on the basis of records collected during the operational period. (p. 16)

Absence of data on activity and specific radionuclides for federal decommissioning wastes in Canada’s 7th report indicates that final decommissioning plans and detailed characterization surveys may not have been done prior to conduct of decommissioning activities.  This would be problematic given that 

With the implementation of the government-owned contractor-operated (GoCo) model at AECL sites, CNL continues to significantly accelerate decommissioning and remediation activities. (Canada’s 7th report, p. 2)

The data shown in Table D.8 in Canada’s 7th report for the Government of Canada’s Whiteshell Laboratories, currently undergoing accelerated decommissioning, differ substantially from those found in the 6th report.

The category of “Research reactor waste and decommissioned reactor waste” for the Whiteshell Laboratories, included in the 6th report, is missing from the 7th report.  Both LLW and ILW at Whiteshell are now labelled as “Decommissioning waste (January 1, 2005, to December 31, 2016).”  

As with the CRL decommissioning waste, this December 31, 2016 date may be an error.  A correction or further explanation is needed.  

Table D.5 in Canada’s 6th report gave volume and activity data for decommissioning wastes at Whiteshell (22 m3 and 148 TBq ILW, 1598 m3 and 6 TBq LLW); Table D.3 in the 6th report gave volume and activity data (863 m3 and 2,794 TBq ILW, 19,700 m3 and 325 TBq LLW) for Whiteshell operations wastes. 

Canada’s 7th report (Table D.8, p. 51) does not provide separate values for Whiteshell decommissioning and operations wastes – both are combined as “Decommissioning waste”.   Activity data for these wastes are now listed as “Not Available”.  

An explanation as to why data on the activity of the Whiteshell wastes were removed from Canada’s 7th report is needed.  As with the CRL decommissioning wastes, lack of activity data for the Whiteshell decommissioning wastes raises concerns that final decommissioning plans and characterization surveys may not have been done before decommissioning activities were carried out.

With regard to the volume of Whiteshell wastes, Table D.8 (p. 51) in Canada’s 7th report provides a figure of 240 m3 of ILW.  This represents only 27% of the 885 m3 of Whiteshell ILW in the 6th report (adding together the separately reported volumes of decommissioning and operations waste).  The 6th report had a footnote stating that “Volumes for ILW/LLW are based on method of storage and do not necessarily represent the actual breakdown of waste into ILW and LLW”.

Canada’s 6th report listed a total of 21,298 m3 of LLW at Whiteshell, including 19,700 m3 of “operations” LLW (in “above-ground concrete bunkers and trenches”) and 1,598 m3 of “decommissioning” LLW (in “above-ground concrete bunkers”).  In Canada’s 7th report, this total volume decreased by 21% to a value of 16,861 m3 of LLW in “above-ground concrete bunkers”.  

Canada’s 7th report gives no explanation for these considerable decreases in the ILW and LLW inventories at Whiteshell.  One possibility is that decommissioning wastes have already been shipped to Chalk River, even though Canada’s 7th report implies that this would not be done until approval was granted for the proposed CRL landfill:

“For the wastes that are currently on-site, CNL is planning to transport certain LLW and other suitable wastes from Whiteshell to CRL for disposal in the proposed NSDF” (p. 297).

The 7th report should explain the 73% decrease in ILW volume and the 21% decrease in LLW volume at the Whiteshell Laboratories. 

Accurate accounting of volumes and activities for the Whiteshell decommissioning wastes is of particular importance, given that the contract between AECL and the consortium of multinational engineering firms includes a special “target cost” agreement that provides bonuses for decommissioning Whiteshell as quickly as possible.  

With regard to Canada’s method of waste classification, the 6th report says:

A definitive numerical boundary between the various categories of radioactive waste – primarily between LLW and ILW – cannot be provided because activity limitations differ between individual radionuclides and radionuclide groups, and will be dependent on short- and long-term safety-management considerations. For example, a contact dose rate of two millisieverts per hour (mSv/h) has been used in some cases to distinguish between LLW and ILW.

A much different waste classification is found in the 7th report:

LLW contains material with radionuclide content above established clearance levels and exemption quantities, but generally has limited amounts of long-lived activity. For orientation purposes only, a limit of 400 Bq/g on average (and up to 4,000 Bq/g for individual waste packages) for long-lived alpha emitting radionuclides can be considered in the classification process. For long-lived beta and/or gamma emitting radionuclides, such as carbon-14, chlorine-36, nickel-63, zirconium-93, niobium-94, technetium-99 and iodine-129, the allowable average activity concentrations can be considerably higher (up to tens of kBq/g) and can be specific to the site and disposal facility. LLW requires isolation and containment for up to a few hundred years.

A similar classification of LLW is found in the NSDF Project Waste Acceptance Criteria (p. 36).  Both resemble the description of LLW in IAEA General Safety Guide GSG-1, Classification of Radioactive Waste. However, neither the new LLW classification in Canada’s 7th report, nor CNL’s LLW classification for its “NSDF”, would appear to identify wastes suitable for disposal in a landfill-type facility.  

As noted earlier, landfill-type facilities are suitable for disposal only Very Low Level Waste (VLLW) – typically, soil and rubble with low levels of radioactivity and very limited concentrations of longer lived radionuclides.  Past activities at CRL related to extraction of isotopes from irradiated fuels and targets (e.g., the plutonium recovery facility, the plutonium tower, the waste water evaporator, the nitrate plant, the thorium pit, the molybdenum-99 processing facility), have left a legacy of long-lived wastes that almost certainly will require management as ILW.

After AECL contracted a consortium of multinational engineering firms to operate the Government of Canada’s nuclear sites in 2015, Canada’s Parliament greatly increased annual appropriations to AECL for decommissioning and waste management. With this increased funding for accelerated decommissioning, and plans for three new disposal facilities for the Government of Canada’s wastes (the CRL landfill, and entombment of the NPD and WR-1 reactors), clear, transparent,  accurate and up-to-date data on federal radioactive wastes should be a high priority for Canada.

Although Canada’s 7th report claims (p. 189) that “Since the Sixth Review Meeting, significant progress has been made in developing and implementing long-term solutions for L&ILW at AECL sites which will address more than half of Canada’s inventory of these waste types,” this claim is not supported by evidence.  Although the Annex of the report describes CRL waste management areas A, B, C, D, E, F, G, H, and J; the Liquid dispersal area; Acid, chemical and solvent pits; Waste tank farm; Ammonium nitrate decomposition plant; and Thorium nitrate pit; it does not indicate that “long-term solutions” have been developed for radioactive wastes in any of these areas.

In summary, Canada’s 7th report could be revised to 

  • include all available data on activity and specific radionuclides for the Government of Canada’s radioactive wastes stored at CRL and Whiteshell;
  • explain the changes  in data for ILW, LLW, and contaminated soils at CRL  and Whiteshell in the 7th report relative to the 6th report, including information on the “better characterization” of ILW;
  • explain why data for wastes arising from decommissioning activities at Chalk River and Whiteshell are shown as not having been updated since 2017;
  • clarify whether final decommissioning plans and detailed characterization surveys were completed prior to conduct of accelerated decommissioning activities at CRL and Whiteshell;
  • explain why the separate table of wastes arising from decommissioning activities found in the 6th report was removed from the 7th report; 
  • clarify that the proposed “NSDF” at CRL would resemble a municipal landfill; and
  • provide evidence that long-term solutions have been developed for remediation of the CRL waste management  areas.

Addressing these issues would add rigour and credibility to Canada’s 7th report. 

We hope this note can stimulate discussions during the Seventh Review Meeting

Thank you for your attention to this matter.

Best regards,

Ole Hendrickson, Ph.D. (ole@nrtco.net)

Researcher, Concerned Citizens of Renfrew County and Area

cc:  cnsc.info.ccsn@canada.ca

Table B-2 Summary of Waste Management Areas at CRL and Estimates of Waste Volumes and Radioactivity Content 

Source: Chalk River Laboratories Comprehensive Preliminary Decommissioning Plan, CPDP-508300-PDP-001, Revision 2, March 2014 

AreaPeriod of OperationDescriptionWaste Volume (m3)
Major Activity (1)Notes
Designation

SolidLiquidTypeTBq
Waste Management Area A
Liquid Wastes
Various drummed and bottled liquids emptied into below-grade concrete structures.n.a.33N/AN/ALimited records for drummed and bottled liquids buried prior to 1956
Solid Wastes1946-1955Liquid wastes discharged into trenches in 1953 (4,500 m3), 1954 September (7.2 m3) and 1955 February (50 m3) resulting in contaminated soil. Solid wastes emplaced in unlined trenches and a variety of “special burials”, such as the NRX calandria.21,200Misc. liquids
Mixed FPN/ALimited records for solid wastes buried prior to 1955. Source of a groundwater plume.
Liquid Dispersal Area
Reactor Pit #11953-1998Liquid waste discharged to natural depression between 1953 and 1956 resulting in contaminated soil. Lightly contaminated equipment and suspect soils later used to fill depression.7,100n.a.β/γ α
100 0.1
Estimated disposal of 74 TBq 90Sr plus 100 g (Pu equivalent) of alpha-emitters. Source of a groundwater plume.
Laundry Pit1956-1957Aqueous waste from Decontamination Centre and Laundry discharged to engineered pit resulting in contaminated soil. 4,000n.a.β/γ α0.06 0.0003Small inventory compared with other LDA pits. 
Chemical Pit1956-1995Liquid aqueous waste from site labs and chemical operations discharged to a gravel-filled pit resulting in contaminated soil.17,700n.a.β/γ α  Tritium230 0.4 70Source of a groundwater 90Sr plume. Groundwater from Chemical Pit plume is subject of pump and treat program.
Reactor Pit #21956-2000Lightly contaminated water from Rod Storage Bays, and NRX & NRU operations resulting in contaminated soil.28,200n.a.β/γ α Tritium500 0.5 1,000Source of a groundwater plume.
Waste Management Area B
Sand Trenches1953-1963Solid wastes in unlined trenches covered with sand: Intermediate Level Radioactive Waste (ILW) emplaced prior to 1956 August, only Low Level Waste (LLW) emplaced after 1956 September.~9,000Misc. bottled liquidsMixed LLW and ILW
~75Use discontinued in favour of engineered structures. Limited inventory data. Source of two separate groundwater plumes.
Asphalt-lined trenches
1955-1959Intermediate-level solid wastes, i.e., wastes having external fields >100 mR/h at 30 cm, that were emplaced in asphalt-lined and –capped trenches1,600Misc. bottled liquidsILWN/AEstimated to contain 0.6 TBq of 239Pu.
Rectangular Concrete bunkers1959-1979Low level solid wastes in rectangular concrete bunkers. (Below grade but above the water table)8,500ResidualLLWA
Special burials1955-1973Various materials including the NRU and the second NRX calandrias.914*220*

Estimates are available for individual burials.
Circular concrete bunkers1979 – presentLow level solid wastes. (Below grade but above the water table)
6,850ResidualLLWA

Tile Holes – Nuclear Reactor Fuels1956 – presentReactor fuel high-level wastes in vertical, below-grade facilities.
120n.a.Used FuelAEstimates available for fissile material quantities. Fuel-bearing structures are the subject of a remediation program. Certain HEU fuels are candidates for return to U.S.
Tile Holes – 99Mo wastes1970 -presentHigh-level wastes from 99Mo production200n.a.ILWN/AEstimates available for fissile material quantities.
Tile Holes – other wastes1956 -presentA variety of high level wastes including reactor components.950n.a.ILWN/ACell wastes, reactor components, Rod Bay wastes.
Waste Management Area C
C Extension1993-2006Low level solid waste (external fields <100 mR/h at 30 cm) in unlined trenches. Higher proportion of drummed waste than Area C.9,000ResidualLLWACharacterization data available for some radionuclide inventories. Source of groundwater plume.
Sand Trenches1963-2006Low-level solid waste (external fields <100 mR/h at 30 cm) in unlined trenches. Total area is approx. 4.5 ha; impermeable cover installed on entire area in 2013. Waste is half from CRL and half from across Canada including NPD.100,000Drummed & bottled liquids
LLWN/ALimited characterization data for inventories. Source of a groundwater plume.
AreaPeriod of OperationDescriptionWaste Volume (m3)
Major Activity (1)Notes
Designation

SolidLiquidTypeTBq
Waste Management Area D1976 – presentFenced gravel compound used for aboveground storage of potentially contaminated equipment, materials and drummed liquids. Not a burial site. A Mixed Waste Facility used for temporary storage, sampling and bulking is also in WMA D.760 (LLW)
LLWASmall numbers of transient drums may be stored at any particular time. The drummed liquids (lightly contaminated aqueous wastes and waste oils) are stored in marine containers.
Acid, Chemical and Solvent Pits1982-1987Small fenced compound containing three small pits, which as the names imply were used for different non-active liquid wastes and very small quantities of solid wastes.Acid: minorAcid: 11.2 Chem.: 2.7 Sol.:  5.3


Acid: Hydrochloric, Sulphuric, Nitric, Chromic acids, potassium carbonate powder, citric powder and acid batteries. Chemical: Scintillation fluids, Alconox and other cleaning agents, ammonia, alkylating agents, others. Solvent: Mixed solvents, oils, scintillation solutions, ammonia, varsol, acetone, others.
Waste Management Area E1977-1984Used for disposition of lightly contaminated & suspect bulk materials (building debris and soils) from the CRL Controlled Area.N/An.a.Suspect slightly contaminatedN/AThe volume of suspect contaminated materials is believed to be a small fraction of the total volume of materials stored here.
Tank Farm1961-1968Tank Farm with intermediate to high-level wastes in tanks in concrete vaults with leak-detection systems  Intermediate – T-40F (secondary concrete containment), T-40E (empty), T-40D (concrete pad) High level – T-283A, B, C, D (all with secondary concrete containment)n.a.68β/γ α
150Monitoring & surveillance confirms containment of these wastes and the facility includes emergency transfer lines.
Waste Management Area F1976-1979Contaminated soils and slags from Port Hope, Albion Hills, Mono Mills and Ottawa stored above the water table in sand valley. Unsuccessful clay cover.~380,000zeroRadium0.5Approx. 515 GBq Total 226Ra,  4 – 13 Mg Arsenic,  80 Mg U.
Waste Management Area G1989-presentNPD spent fuel dry storage facility – aboveground concrete canisters.
4,921 (bundles)
zeroIrrad. UAComplete inventory data available. Monitoring & surveillance confirms containment within structures.
Waste Management Area H (MAGS and SMAGS)2001-presentPrefabricated metal and concrete storage buildings with capability of storing 865 m3and approximately 4,000 m3 each, respectively, of compacted LLW in B-1000 compactor boxes, 45-gallon drums (204 liters), wooden crates, boxes and B-25 containers. Bulk materials and NRX stack pieces are also stored in WMA H.9,000n.aMixed FPN/AAll waste will be removed by Operations prior to turnover to Decommissioning. Some residual contamination may be present as a result of operational activities.
WMA J Bulk Material Landfill (BML)2010–presentEngineered landfill used for the storage of sewage sludge for the CRL sewage treatment plant1,600n.a.Mixed FP
~10-4
Leachate is transferred to the sewage treatment plant.
Nitrate Plant1953-1954Discharges of mixed fission products in salt solutions to limed pit following a process accident. Decontaminating solutions also released. Contaminated rubble from Building 233 demolition.
3,400n.a.β/γ60Estimated 60 TBq of β/γ activity (35% 90Sr) in liquid releases – small α inventories. Plant demolished and buried on-site, no data for solid waste inventories.
.Thorium Pit1955-1960Reprocessing wastes from operation of the 233U extraction facility.
150n.a.Nat. Th, 233U and mixed FPAApproximate total of 45 m3 reprocessing solution discharged in separate dispersals to crib containing ammonium carbonate (~4,000 kg of nat. Th, 27 g 233U).
Above Ground Buildings and Structures in Waste Management Areas
Buildings and Structures in WMAs1953 – presentVarious buildings/gatehousesN/An.a.N/AN/A

(1) Activity at time of emplacement – not corrected for decay N/A = no quantitative data available n.a. = not applicable A = quantitative data available 

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