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Control of Emissions from Nonroad Large Spark Ignition Engines and Recreational Engines (Marine and Land-based); Extension of Comment Period


[Federal Register: May 1, 2002 (Volume 67, Number 84)]
[Proposed Rules]
[Page 21613-21617]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr01my02-23]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Parts 89, 90, 91, 94, 1048, 1051, 1065, and 1068
[AMS-FRL-7204-7]
RIN 2060-AI11
 
Control of Emissions from Nonroad Large Spark Ignition Engines 
and Recreational Engines (Marine and Land-based); Extension of Comment 
Period

AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule; reopening of comment period.

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SUMMARY: The Environmental Protection Agency published in the Federal 
Register of October 5, 2001, a notice of proposed rulemaking proposing 
new emission standards for large spark-ignition engines, recreational 
vehicles using spark-ignition engines, and recreational marine diesel 
engines. The Agency received a number of comments noting considerable 
information on strategies to reduce permeation emissions and suggesting 
that requirements controlling such emissions be proposed for land-based 
recreational vehicles. As a result, EPA is requesting comment on 
whether it should finalize an emission standard controlling permeation 
emissions from fuel tanks and hoses for land-based recreational 
vehicles. This document provides a detailed discussion regarding this 
issue and discusses what form a final standard regulating these 
permeation emissions would take. This document extends the period for 
written comments on that notice of proposed rulemaking to May 31, 2002. 
The extension only applies to comments on whether EPA should finalize 
emission standards regulating permeation emissions from land-based 
recreational vehicles, and, if so, the form such standards would take.

DATES: Comments: Send written comments on this notice by May 31, 2002.

ADDRESSES: You may send written comments in paper form to Margaret 
Borushko, U.S. EPA, National Vehicle and Fuels Emission Laboratory, 
2000 Traverwood, Ann Arbor, MI 48105. We must receive them by the date 
indicated under DATES above. You may also submit comments via e-mail to 
``NRANPRM@epa.gov.'' In your correspondence, refer to Docket   
A-2000-01.

FOR FURTHER INFORMATION CONTACT: Margaret Borushko, U.S. EPA, National 
Vehicle and Fuels Emission Laboratory, 2000 Traverwood, Ann Arbor, MI 
48105; Telephone (734) 214-4334; FAX: (734) 214-4816; E-mail: 
borushko.margaret@epa.gov. EPA hearings and comments hotline:   
734-214-4370.

SUPPLEMENTARY INFORMATION: On October 5, 2001, we published a Notice of 
Proposed Rulemaking (NPRM) for the Control of Emissions from Nonroad 
Large Spark Ignition Engines and Recreational Engines (Marine and Land-
Based) (66 FR 51098). The comment period for the NPRM was originally 
scheduled to end on December 17, 2001; however, the comment period was 
extended to January 18, 2002 as a result of several requests for 
additional time. During this comment period, we received many comments 
from a wide range of commenters covering a broad range of issues. One 
of the issues that was raised by several commenters \1\ was the 
information related to the control of evaporative emissions related to 
permeation from fuel tanks and fuel hoses, and the lack of any proposed 
emission standards regulating these emissions from land-based 
recreational vehicles.
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    \1\ See public docket A-2000-1 IV-D-186, items IV-D-198, and IV-
D-202.
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    We have conducted our initial review and assessment of the issues 
and data raised in these comments, and believe that they have merit and 
should be presented to the public for further consideration. Therefore, 
we are asking for comment on the possibility of finalizing standards 
regulating permeation emissions from land-based recreational vehicles. 
Our work on evaporative emissions from marine applications indicates 
that the permeation emissions from tanks and hoses are a large part of 
the total emissions from these applications. Additionally, commenters 
stated that work done by the California Air Resources Board (ARB) on 
permeation emissions from plastic fuel tanks and rubber fuel line hoses 
for various types of nonroad equipment as well as portable plastic fuel 
containers indicated that these permeation emissions are a concern. Our 
own investigation into the hydrocarbon emissions related to permeation 
of fuel tanks and fuel hoses with respect to marine applications 
supports the concerns raised by the commenters. Given this, we are 
assessing the possibility of regulating permeation emissions from other 
vehicle types, including, off-highway motorcycles (OHM), all-terrain 
vehicles (ATVs) (including utility work and specialty

[[Page 21614]]

vehicles), and snowmobiles that may use fuel tanks or hoses with less-
than-optimal control of permeation emissions.

I. Description of Regulatory Concept

    We are reopening the comment period for land-based recreational 
vehicles to request comment on whether we should finalize standards 
that would require low permeability fuel tanks and hoses on off-highway 
motorcycles, ATVs, and snowmobiles starting with the 2006 model year. 
The requirements would phase-in beginning for all three types of 
recreational vehicle at 50 percent in 2006 and 100 percent in 2007. 
This is the same start year as was proposed in the October 5, 2001 NPRM 
for exhaust emission control for these three types of recreational 
vehicle. We believe cost-effective technologies exist to significantly 
reduce permeation emissions. Because all of these vehicles use high 
density polyethylene (HDPE) tanks, manufacturers would in all 
likelihood have to employ one of the barrier technologies (e.g., a 
fluorination or sulfonation treatment) described below to meet the 
standards. The use of metal fuel tanks would also meet the standards, 
since metal tanks do not experience any permeation losses. Fuel tanks 
built with permeation resistant barrier layers would also be possible, 
but could likely be more expensive and employ production practices not 
used on HDPE tanks in these applications. We also request comment on 
promulgating standards that would also require the use of low 
permeability fuel hoses on all land-base recreational vehicles, 
starting with 50 percent implementation in the 2006 model year and 100 
percent in 2007.
    Even though snowmobiles do not usually experience year around use, 
as is the case with ATVs, off-highway motorcycles, etc., we are 
including snowmobiles in this request for comment because it is common 
practice among snowmobile owners to store their snowmobiles in the off-
season with fuel in the tank (typically half full to full tank). A fuel 
stabilizer is typically added to the fuel to prevent gum, varnish, and 
rust from occurring in the engine as a result of the fuel sitting in 
the fuel tank and fuel system for an extended period of time, but this 
does not reduce permeation. Thus, snowmobiles experience fuel 
permeation losses just like off-highway motorcycles and ATVs. We 
request comment on the fuel storage practices of snowmobile operators.
    EPA requests comments in several areas with regard to the way in 
which requirement might be implemented. First, we request comment on 
the form these standards would take (e.g., whether there should be 
absolute numerical limits on a gram per gallon basis or if the standard 
should be expressed as a grams per square meter per day of tank surface 
area). Given differences in wall thickness, tank geometry, material 
quality, and pigment, we also ask comment on whether an emission credit 
averaging, banking, and trading (ABT) scheme would be helpful and 
necessary for the fuel tank permeation requirements. If we do adopt ABT 
provisions, we would envision an ABT program similar in nature to that 
used for heavy-duty engines (see 40 CFR 86.004-15) but substituting 
fuel tank volume for transient conversion factor.
    Information indicates that permeation emissions can essentially be 
eliminated at minimal cost. We are interested in comments on provisions 
that would require near zero permeation levels, with a small factor to 
address issues such as measurement accuracy or repeatability. Available 
data indicate that 95 percent reductions are achievable. Achieving 
reductions at this level repeatedly would require tanks with consistent 
material quality, amount, and composition including pigments and any 
additive packages. This would enable process and efficiency 
optimization and consistency in the effectiveness of surface treatment 
processes. These reductions imply a tank permeability standard of 0.04 
grams per gallon per day at 30 deg.C or about 0.4 to 0.5 grams per 
square meter per day. We are also requesting comments on the estimates 
for emissions reductions and costs presented in this notice.
    Certification with these fuel tank requirements would require 
testing such as that described in 49 CFR 173 appendix B, California ARB 
test method 513, or equivalent, as laid out in the docket. Normally 
five tests would be required and the average value used. This test is 
based on a change in filled tank mass over a period of time. We would 
consider a temperature of 28 deg.C ± 28 deg.C to be an 
appropriate range for our testing requirement. Vehicle manufacturers or 
tank manufacturers could certify and either could contract with a party 
providing barrier treatment or another source to do the required 
testing.
    With regard to fuel hoses, the requirement would apply to any line 
normally containing liquid gasoline in storage or operation. These fuel 
hoses could be certified as being manufactured in compliance with 
certain accepted SAE specifications. These certification statements 
could be done on a family basis, or possibly a blanket statement could 
cover a manufacturer's entire product line. Similarly, near zero 
permeation emissions from hoses are feasible. Assuming a factor to 
address testing concerns, EPA expects that 95 percent reductions over 
uncontrolled emission levels for permeation are achievable for rubber 
hoses. For fuel hoses, we would consider a standard of 5 grams per 
square meter per day at 23 deg.C, as would be measured using the 
recommended test procedure in SAE J1527.
    We also request comment on implementing requirements such as those 
described above by allowing the manufacturer to submit a statement at 
the time of certification that the fuel tanks and hoses used on their 
products meet standards, specified materials, or construction 
requirements based on testing results. For example, a manufacturer 
using plastic fuel tanks could state that the family at issue is 
equipped with a fuel tank with a low permeability barrier treatment 
such as fluorination and provide EPA the supporting test information as 
described above for the worst case configuration in the family. Key 
parameters could include tank geometry, wall thickness, pigment, 
additive package, and amount of material in the tank. All tanks in the 
family would require the same level or type of treatment in production.
    We request comment on these and other options that would enable 
regulation and enforcement of low permeability requirements. Most 
notably we are interested in provisions that would allow the 
certificate holder assurance that the treated tanks and fuel hoses 
provided by suppliers/vendors consistently meet the performance 
specifications laid out in the certificate and provisions regarding 
liability.
    Information concerning potential draft regulations covering these 
implementation provisions as discussed above can be found in the public 
docket (A-2000-1).
    Another important element of the test requirements is fuel quality. 
Permeation testing generally involves a gasoline or hydrocarbon mixture 
and may involve alcohol as well. There are at least four possible test 
fuels for consideration. These include: (1) Neat gasoline such as 
current EPA certification fuel, (2) certification quality gasoline with 
a 10% ethanol blend as is prescribed for the Tier 2 automobile 
evaporative standards, (3) ASTM D471 test fuel C (50% iso-octane/50% 
toluene) and, (4) ASTM D471 test fuel I (test fuel C with 15% 
methanol). Permeation is greater with alcohol-blend fuels and since 
there

[[Page 21615]]

is a significant amount of ethanol and other alcohols used in gasohol 
and other summer and winter gasolines Tier 2 type evaporative test fuel 
is of special interest. We are requesting comments on the test fuel.

II. Technological Feasibility

    EPA believes there are available technologies that can reduce 
permeation emissions to near-zero levels. For example, fluorinated fuel 
tanks and low permeability hoses, which are already available for small 
additional costs, could reduce permeation of tanks and hoses by 95 
percent or more. The application of these technologies to land-based 
recreational vehicles appears to be relatively straightforward, with 
little cost and no adverse performance or aesthetic impacts. In 
addition, the control technology would generally pay for itself over 
time by conserving fuel that would otherwise evaporate.
    A recent regulation in California requires a change from untreated 
high-density polyethylene (HDPE) plastic to fluorinated or sulfonated 
HDPE portable gasoline cans. Fuel tanks used by land-based recreational 
vehicles are all made of HDPE. Comments from California ARB suggest 
that the same technology used for small portable HDPE gasoline fuel 
cans could be readily applied to the fuel tanks of recreational 
vehicles.
    As discussed above, there are two types of fuel tank barrier 
processes that can be employed to reduce or eliminate permeation in 
HDPE plastic tanks. The fluorination process causes a chemical reaction 
where exposed hydrogen atoms are replaced by larger fluorine atoms 
which form a barrier on the surface of the fuel tank. In this process, 
fuel tanks are stacked in a steel basket and placed in a sealed 
reactor. All of the air in the reactor is removed and replaced with 
fluorine gas. By pulling a vacuum in the reactor, the fluorine gas is 
forced into every crevice in the fuel tanks. As a result of this 
process, both the inside and outside surfaces of the fuel tank are 
treated. As an alternative, for tanks that are blow molded, the inside 
surface of the fuel tank can be exposed to fluorine during the blow 
molding process. In a similar barrier strategy, called sulfonation, 
sulfur trioxide is used to create the barrier by reacting with the 
exposed polyethylene to form sulfonic acid groups on the surface. 
Either of these processes can be used to reduce gasoline permeation by 
more than 95 percent.\2\
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    \2\ Kathios, D., Ziff, R., Petrulis, A., Bonczyk, J., 
``Permeation of Gasoline and Gasoline-alcohol Fuel Blends Through 
High-Density Polyethylene Fuel Tanks with Different Barrier 
Technologies,'' SAE Paper 920164, 1992, Air Docket A-2000-01, 
Document No. II-A-60.
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    The majority of fuel hoses used in recreational vehicles today are 
made of nitrile rubber which has a high rate of fuel permeation.\3\ 
However, low permeation hoses are available that could be used in these 
applications. Low permeability hoses produced today are generally 
constructed in one of two ways: using a low permeability material or a 
low permeability barrier layer. One hose design, already used in some 
marine applications, uses a thermoplastic layer between two rubber 
layers to control permeation. This thermoplastic barrier may either be 
nylon or ethyl vinyl alcohol. In automotive applications, other barrier 
materials are used such as fluoroelastomers and fluoroplastics which 
are two to three orders of magnitude less permeable than hoses 
currently on recreational vehicles.\4\ By replacing rubber hoses with 
low permeability hoses, permeation emissions through the fuel hoses can 
be reduced by more than 95 percent. An added benefit of low 
permeability lines is that some fluoropolymers can be made to conduct 
electricity and therefore can prevent the buildup of static charges.
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    \3\ Stahl, W., Stevens, R., ``Fuel-Alcohol Permeation Rates of 
Fluoroelastomers, Fluoroplastics, and other Fuel Resisitant 
Materials,'' SAE 920163, 1992.
    \4\ Denbow, R., Browning, L., Coleman, D., ``Report Submitted 
for WA 2-9, Evaluation of the Costs and Capabilities of Vehicle 
Evaporative Emission Control Technologies,'' ICF, ARCADIS Geraghty & 
Miller, March 22, 1999.
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III. Projected Impacts

A. Economic Impact

    Off-highway motorcycle fuel tanks range in capacity from 
approximately one gallon on some smaller youth models to about three 
gallons on some enduro motorcycles. For ATVs, fuel tanks range from one 
gallon for the smaller youth models to five gallons for the larger 
utility models. Finally, snowmobile fuel tanks range from 10 gallons to 
about 12 gallons. We estimate that fluorination of the fuel tanks would 
cost about $0.50 per gallon of capacity. Cost is related to fuel tank 
size because the cost of the treatment to any given level of 
effectiveness depends on how many fuel tanks can be fit into the 
fluorination chamber and the amount of polymer to be treated. It is 
estimated that shipping, handling, and overhead costs would be an 
additional $0.22 to $0.81 per fuel tank depending on tank volume. Table 
1 presents estimated costs of fuel tank permeation control using 
fluorination.
    EPA's examination of land-based recreational vehicles indicated 
that none of these vehicles are equipped with fuel hoses that 
significantly reduce or eliminate permeation. The incremental cost of a 
fuel line with low permeation properties for recreational vehicles is 
estimated to be about $1.00 per foot. For off-highway motorcycles, it 
is estimated that they use approximately one to two feet of fuel line 
on average. For ATVs, we estimate one foot of fuel line on average. 
Snowmobiles are a little more complex since they use multi-cylinder 
engines (either two or three cylinders). For two cylinder engines we 
estimate two to three feet of fuel line and for three cylinder engines 
we estimate three to four feet of fuel line. We are interested in 
collecting more information regarding fuel hoses currently used on 
land-based recreational vehicles, in particular regarding the typical 
length, the material, and the permeation properties. Table 1 also 
presents estimated costs of hose permeation control. Fuel savings due 
to reducing permeation, which are discussed later, are not included in 
this table. The costs in Table 1 include a 30 percent manufacturer 
markup from the vehicle manufacturer.

        Table 1.--Average Cost of Permeation Control per Vehicle
------------------------------------------------------------------------
                                               OHM    ATVs   Snowmobiles
------------------------------------------------------------------------
Average fuel tank capacity [gallons].......       3       4         11
Fluorination cost (includes shipping/         $2.19   $2.93      $5.43
 handling/overhead)........................
Average hose length [feet].................     1.5       1        3.5
Increased Hose Cost........................    1.95    1.30       4.55
Total Cost Increase........................    4.14    4.23       9.98
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B. Environmental Impact

    As was discussed earlier, EPA as well as California ARB, have 
conducted permeation testing with regard to permeation emissions from 
HDPE plastic tanks. Permeation rates varied from 0.2 to1.0 grams per 
gallon per day with an average value of 0.76 g/gal/day. This data was 
based on tests with an average temperature of about 29 deg.C. 
Temperature has a first-order effect on the rate of permeation. 
Roughly, permeation doubles with every 10 deg.C increase in 
temperature. For example, we estimate that at 23 deg.C, the average 
value for these fuel tanks would be about 0.50 g/gal/day. This test 
data can be found in the docket

[[Page 21616]]

    Fuel hoses on recreational vehicles generally have an inside 
diameter of about 6 mm (1/4 inch) and a permeation rate of 550 grams 
per square meter per day for uncontrolled hoses at 23 deg.C. We base 
this permeation rate on the SAE J30 requirement for R7 fuel hose.\5\ 
For 1 foot of fuel hose, this yields an emission rate of 5.0 g/day at 
23 deg.C.
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    \5\ SAE J30, ``Fuel and Oil Hoses,'' Surface Vehicle Standard, 
Society of Automotive Engineer Revised June 1998.
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    Table 2 presents national totals for permeation emissions from 
recreational vehicles. These permeation estimates are based on the 
emission rates discussed above and population and turnover estimates 
used in our draft NONROAD emissions model.\6\ The daily temperatures by 
region (6 regions are used) are based on a report which summarizes a 
survey of dispensed fuel and ambient temperatures in the United 
States.\7\
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    \6\ This information is also available in Chapter 6 of the 
Regulatory Support Document for the NPRM. For more detailed 
information on the draft NONROAD model, see our Web site at 
www.epa.gov/otaq/nonrdmdl.htm.
    \7\ API Publication No. 4278, ``Summary and Analysis of Data 
from Gasoline Temperature Survey Conducted at Service Stations by 
American Petroleum Institute,'' Prepared by Radian Corporation for 
American Petroleum Institute, November 11, 1976, Docket A-2000-01, 
Document II-A-16.

                           Table 2.--Potential Permeation Emission Control Reductions
                                                    [tons/yr]
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              Category                       Scenario             2005         2010         2020         2030
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Off-highway motorcycles.............  baseline..............        6,203        6,434        6,903        6,847
                                      control...............        6,203        3,258          188          651
                                      reduction.............            0          246          519          563
ATVs................................  baseline..............       24,891       33,136       38,856       36,777
                                      control...............       24,891       21,574        4,139        7,046
                                      reduction.............            0       11,562       34,716       29,731
Snowmobiles.........................  baseline..............       16,083       16,681       17,899       17,679
                                      control...............       16,083        8,462          517        2,320
                                      reduction.............            0        8,219       17,382       15,359
                                                             ---------------------------------------------------
    Total...........................  baseline..............       47,178       56,251       63,658       61,303
                                      control...............       41,178       33,294        4,845       10,018
                                      reduction.............            0       22,957       58,813       51,286
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C. Cost per Ton of Emissions Reduced

    The average lifetimes of typical recreational vehicles are 
estimated to be about 9 years for off-highway motorcycle and 
snowmobiles and 13 years for ATVs. Permeation control techniques can 
reduce emissions by about 95 percent for plastic fuel tanks and more 
than 99 percent for rubber hoses. Multiplying this efficiency and these 
emission rates by the life of the vehicles and discounting at 7 percent 
gives us lifetime per vehicle emission reductions. Using the cost 
estimates above, we have also determined cost per ton of hydrocarbons 
reduced. These estimates are presented Table 3.

                       Table 3.--Estimated Cost Per Ton of HC Reduced Without Fuel Savings
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                                                                                                      Discounted
                                                                                          Lifetime     cost per
                 Category                               Source             Cost  (NPV)   reductions    ton  ($/
                                                                                        (NPV, tons)      ton)
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Off-highway motorcycles...................  fuel tank....................        $2.19       0.0026         $828
                                            fuel hose....................        $1.95       0.0315          $62
                                                                          --------------------------
    Total.................................  .............................        $4.14       0.0342         $121
ATVs......................................  fuel tank....................        $2.93       0.0044         $664
                                            fuel hose....................        $1.30       0.0263          $49
                                                                          --------------------------
    Total.................................  .............................        $4.23       0.0307         $138
Snowmobiles...............................  fuel tank....................        $5.43       0.0079         $689
                                            fuel hose....................        $4.55       0.0598          $76
                                                                          --------------------------
    Total.................................  .............................        $9.98       0.0677         $147
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    Because these emissions are composed of otherwise useable fuel that 
is lost to the atmosphere, measures that reduce permeation emissions 
can result in potentially significant fuel savings. Table 4 presents 
our estimates of these fuel savings as well as adjusted cost per ton 
estimates which consider these fuel savings. The value of the fuel 
savings presented are based on a discount rate of 7 percent and an 
average nontax gasoline fuel price of $1.10 per gallon. As is shown 
below, the fuel savings are generally larger than the cost of using low 
permeation technology. To the consumer this is a net cost savings over 
the vehicle life of about $8 for off-highway motorcycles, $7 for ATVs, 
and $14 for snowmobiles. It is estimated that this technology would 
save about 20 million gallons of gasoline per year when fully 
implemented.

[[Page 21617]]

                        Table 4.--Estimated Cost Per Ton of HC Reduced With Fuel Savings
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                                                                                          Value of    Discounted
                                                                            Fuel saved      fuel       cost per
                 Category                               Source              (gallons)     savings      ton  ($/
                                                                                           (NPV)         ton)
----------------------------------------------------------------------------------------------------------------
Off-highway motorcycles...................  fuel tank....................          1.1        $0.96         $465
                                            fuel hose....................         13.4        11.45        (301)
                                                                          --------------------------
ATVs......................................  fuel tank....................          2.2         1.64          292
                                            fuel hose....................         12.9         9.79        (323)
                                                                          --------------------------
Snowmobiles...............................  fuel tank....................          3.4         2.82          326
                                            fuel hose....................         25.5        21.71        (287)
    Total.................................  .............................         28.8        24.57        (216)
----------------------------------------------------------------------------------------------------------------

    Dated: April 25, 2002.
Elizabeth Craig,
Acting Assistant Administrator for Air and Radiation.
[FR Doc. 02-10730 Filed 4-30-02; 8:45 am]
BILLING CODE 6560-50-P


 
 


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