                  UNITED STATES COURT OF APPEALS
                      FOR THE FIRST CIRCUIT
                                           

No. 93-2122

             LABOR RELATIONS DIVISION OF CONSTRUCTION
            INDUSTRIES OF MASSACHUSETTS, INC., ET AL.,

                      Plaintiffs-Appellees,

                                v.

        INTERNATIONAL BROTHERHOOD OF TEAMSTERS, CHAUFFERS,
         WAREHOUSEMEN AND HELPERS OF AMERICA, LOCAL #379,

                       Defendant-Appellant.

                                           

           APPEAL FROM THE UNITED STATES DISTRICT COURT

                FOR THE DISTRICT OF MASSACHUSETTS

           [Hon. A. David Mazzone, U.S. District Judge]
                                                      

                                           

                              Before

                      Breyer,* Chief Judge,
                                          
                  Coffin, Senior Circuit Judge,
                                              
                  and Torruella, Circuit Judge.
                                              

                                           

     Paul F. Kelly,  with whom Anne R. Sills and Segal, Roitman &amp;
                                                                 
Coleman were on brief for appellant.
       
     John D. O'Reilly  III, with  whom O'Reilly &amp;  Grosso was  on
                                                         
brief for appellees.
                                           

                          July 19, 1994
                                           

                    

*   Chief Judge Stephen Breyer heard oral argument in this matter
but did not  participate in the drafting  or the issuance  of the
panel's  opinion.   The remaining  two panelists  therefore issue
this opinion pursuant to 28 U.S.C.   46(d).

          TORRUELLA, Circuit  Judge.   The circumscribed  role of
                                   

federal  courts reviewing  arbitration awards  in labor  contract

disputes is now well established.  As the  Supreme Court found in

United  Paperworkers Int'l Union v. Misco, Inc., 484 U.S. 29, 36-
                                               

45 (1987), courts must resist the temptation  to substitute their

own  judgment about  the  most  reasonable  meaning  of  a  labor

contract for that  of the  arbitrator and avoid  the tendency  to

strike down even an arbitrator's erroneous interpretation of such

contracts.     Instead,   courts  must   confine  themselves   to

determining whether the arbitrator's construction of the contract

was in any way plausible.

          The issue in this case is whether any plausible reading

of a  collective bargaining  agreement  supports an  arbitrator's

ruling   in  a   dispute  over   fringe   benefit  contributions.

Plaintiffs-appellees, J.M.  Cashman, Inc. and R.  Zoppo Co., Inc.

(the  "plaintiffs"  or  "Cashman   and  Zoppo"),  challenged  the

arbitration   order,   which  favored   the  defendant-appellant,

International Brotherhood of Teamsters,  Chauffeurs, Warehousemen

and Helpers of American, Local 379 (the "Union"), in the district

court.   The  district court  vacated the  arbitration award  and

remanded  the dispute to the  arbitrator for a  new resolution of

the  case.   Because  we find  that  the district  court  stepped

outside  of  its  highly  circumscribed  role  of  assessing  the

plausibility of the arbitrator's interpretation  of the agreement

between   the   parties,   we   reverse   the  court's   holding.

Nevertheless,  we agree  with the  district  court that  the case

                               -2-

should  be remanded to the arbitrator for resolution of a related

issue of federal law.

                          I.  BACKGROUND

          This case arises  out of the  arbitration of a  dispute

between the Union and  a group of contractor-employers, including

plaintiffs  Cashman and  Zoppo, involved  in the  construction of

waste water  treatment facilities  in Boston Harbor  (the "Boston

Harbor Project").  On  March 2, 1992, the Union  filed grievances

against Cashman, Zoppo, and six other project employers, claiming

that truck drivers  on the  Boston Harbor Project  who owned  and

drove  their  own  trucks,  so  called "owner-operators,"  should

receive certain  fringe benefit contributions  that the employers

were  already paying  on behalf  of other  Boston  Harbor Project

employees.    The  grievances  asserted that  the  Boston  Harbor

Project  Labor Agreement  ("Project  Agreement"),  signed by  the

Union  and  the employers,  required  that the  same  "health and

welfare  contributions  and all  pension  contributions"  made on

behalf of  other employees  must also  be made on  behalf of  the

owner-operators.

          The employers  claimed that  they did  not have  to pay

fringe benefits on behalf of owner-operators because the contract

did not require it  and, more importantly, because the  Union and

many  of the employers had a long-standing practice of not paying

such  owner-operator  benefits  going  back at  least  twenty-six

years.  According to the employers, this practice was established

after the Union  and certain employer-contractors on a  number of

                               -3-

state  construction projects  (not  including  Cashman and  Zoppo

themselves)  agreed  that, to  the  extent  a nucleus  of  owner-

operator  truck  drivers  would  be  present  on  any  individual

construction project, the  employers would not be required to pay

fringe benefits  for the owner-operators.   The employers working

on  the  Boston Harbor  Project, who  were  required to  sign the

Project  Agreement in  order to  bid initially  on the  work, see
                                                                 

Building  &amp;  Constr.  Trades  Council v.  Associated  Builders  &amp;
                                                                 

Contractors,  Inc., 113 S. Ct.  1190 (1993), rev'g,  935 F.2d 345
                                                  

(1st  Cir. 1991)  (en banc), maintained  that they  expected this

established  practice  to  continue  as  in   previous  projects.

Cashman and Zoppo, however, had never entered into  a contractual

relationship  with the  Union before  the Boston  Harbor Project.

Consequently, no past practices  had been established between the

Union and the plaintiffs themselves.

          Pursuant to the Project Agreement, the dispute over the

fringe benefits was brought  before an arbitrator for resolution.

On January 20, 1993, the  arbitrator found in favor of  the Union

and  ordered the  plaintiffs  and  the  other employers  to  pay,

retroactively, post-grievance benefits  and to pay  future fringe

benefit  contributions on  behalf  of  the  owner-operator  truck

drivers.   In his accompanying opinion,  the arbitrator explained

that  certain provisions  of the  Massachusetts Teamsters'  Heavy

Construction   Agreement   ("Teamsters  Agreement"),   which  was

incorporated into the Project  Agreement, in conjunction with the

Project Agreement itself, explicitly obligated employers to  make

                               -4-

health  insurance  and pension  contributions  on  behalf of  the

owner-operators in question.

          At  issue in  this appeal  is the  arbitrator's finding

that  the past  practice of  not paying  the fringe  benefits for

owner-operators did not bind the parties in this case because the

Project Agreement "wiped the slate clean" of such past practices.

The arbitrator relied on  the following language in  the preamble

of the Project Agreement to support his finding:

            No  practice, understanding  or agreement
            between  a Contractor  and a  Union party
            which is not explicitly set forth in this
            Agreement shall  be binding on  any other
            party  unless endorsed in  writing by the
            Project Contractor.

By  interpreting this language as negating all past practices and

understandings  not  explicitly  set  forth  within  the  Project

Agreement,  the  arbitrator disregarded  the  voluminous evidence

presented  by  the  employers  of  the  established  practice  of

excluding  owner-operators from fringe benefit contributions.  As

a result,  the language  of the  Project Agreement granting  such

benefits was found to be controlling.

          Also at  issue on  appeal is  the  related question  of

whether   the  owner-operator   truck  drivers   are  independent

contractors or  employees.  If they  are independent contractors,

Section 302  of the Labor  Management Relations Act  ("LMRA"), 29

U.S.C.    186,  would prohibit fringe  benefit payments  on their

behalf.    The arbitrator  acknowledged  that  the employers  had

argued that fringe benefit payments for the owner-operators would

be illegal under  Section 302, but he  made no explicit  legal or

                               -5-

factual findings on the issue in his opinion.  While a  rejection

of  the employers'  contention was  implicit in  the arbitrator's

award favoring  the Union, nothing indicates  that the arbitrator

actually determined whether the owner-operators were employees or

independent contractors for purposes of the LMRA.

          Following  the entry of the arbitrator's award, Cashman

and Zoppo filed a complaint in the district court on February 19,

1993, requesting that  the court  vacate the award.   On  summary

judgment,  the  district  court  held  that  the  arbitrator  had

impermissibly exceeded his authority by misapplying the plain and

unambiguous language of the Project Agreement preamble concerning

past  practices, thereby  failing to  duly consider  the evidence

that the parties had a practice of not paying fringe benefits for

owner-operators.    The  district   court  found  that  the  past

practices provision  of the  preamble -- particularly  the words,

"no practice . . . shall be binding on any other party" (emphasis
                                                      

added)  --  clearly  and  unambiguously  meant  that  established

practices between parties A and  B are not meant to  bind outside

party C.  The court found that the phrase could not reasonably be

interpreted to  mean that  all established practices,  even those

between parties A  and B, are completely wiped out by the Project

Agreement.   Consequently, the  court held  that the Union  could

still  be  bound by  the past  practice  of not  requiring fringe

benefit contributions for  owner-operators.   The district  court

vacated  the  arbitrator's award  and  remanded the  case  to the

arbitrator to  determine the merits,  giving proper consideration

                               -6-

to the evidence of past practices.

          The court  also left  for the  arbitrator the  issue of

whether,  in light  of  the court's  holding that  past practices

could   be  considered,   the  owner-operators   are  independent

contractors,  thus rendering  the  payment of  benefits on  their

behalf illegal.

                          II.  ANALYSIS

          A.  Standard Of Review
                                

          It  is well  established that  federal court  review of

labor  arbitral  decisions, particularly  on matters  of contract

interpretation,   is   extremely   narrow  and   "extraordinarily

deferential."  Dorado Beach Hotel Corp. v. Uni n  de Trabajadores
                                                                 

de la Industria Gastron mica Local 610, 959 F.2d 2, 3-4 (1st Cir.
                                      

1992);  see,  e.g.,  Misco,  484 U.S.  at  36-45  (1987); Berklee
                                                                 

College  of Music v. Berklee  Chapter of Mass.  Fed. of Teachers,
                                                                 

Local 4412,  858 F.2d 31, 32  (1st Cir. 1988), cert.  denied, 493
                                                            

U.S. 810 (1989).   The  court may not  supplant the  arbitrator's

determination of the  merits of  a contract dispute,  even if  it

finds that determination  to be erroneous.   Rather, the  court's

task is limited to determining if the arbitrator's interpretation

of the contract is in any way plausible.   Misco, 484 U.S. at 36-
                                                

38;  United Steelworkers  of America  v. Enterprise  Wheel  &amp; Car
                                                                 

Corp.,  363 U.S. 593, 599  (1960) ("[S]o far  as the arbitrator's
     

decision concerns  construction of the contract,  the courts have

no business  overruling him  because their interpretation  of the

contract is  different from  his."); El Dorado  Technical Servs.,
                                                                 

                               -7-

Inc.  v. Uni n General de  Trabajadores de Puerto  Rico, 961 F.2d
                                                       

317, 319 (1st Cir.  1992) ("[A] court should uphold an award that

depends  on  an  arbitrator's  interpretation   of  a  collective

bargaining agreement if it  can find, within the four  corners of

the agreement,  any plausible basis  for that  interpretation.");

Dorado Beach, 959 F.2d at 4; Bacard  Corp. v. Congreso de Uniones
                                                                 

Industriales de Puerto Rico,  692 F.2d 210, 211 (1st  Cir. 1982).
                           

"[A]s long  as  the arbitrator  is  even arguably  construing  or

applying  the  contract  and  acting  within  the  scope  of  his

authority, that  a court is convinced he  committed serious error

does not suffice to  overturn his decision."  Misco, 484  U.S. at
                                                   

38.

          Only in  a few,  exceptional  circumstances are  courts

able  to vacate  an arbitration  award.   When an  arbitrator has

exceeded  his authority  by  ignoring the  clear and  unambiguous

mandates or plain language  of the contract or by  construing the

contract  in a way that cannot possibly be described as plausible

or  rational, a  court  can overturn  the arbitrator's  judgment.

Misco,  484  U.S. at  38 (an  arbitrator's  award "must  draw its
     

essence  from   the  contract  and  cannot   simply  reflect  the

arbitrator's own notions of  industrial justice"); Dorado  Beach,
                                                                

959  F.2d at 4;  Air Line  Pilots Ass'n Int'l v. Aviation Assocs.
                                                                 

Inc., 955 F.2d 90, 93  (1st Cir.), cert. denied, 112 S.  Ct. 3036
                                               

(1992); Strathmore Paper Co.  v. United Paperworkers Int'l Union,
                                                                

900 F.2d 423, 426 (1st Cir. 1990); Georgia-Pacific Corp. v. Local
                                                                 

27,  United Paperworkers Int'l Union, 864 F.2d 940, 944 (1st Cir.
                                    

                               -8-

1988).

          We reject plaintiffs' contention that our review of the

district court's  vacation of an  arbitration award, based  on an

alleged impermissible interpretation of a contract, is made under

the clearly erroneous standard.   In this case, all  deference is

due to  the arbitrator's interpretation  of the contract,  not to

the interpretation of  the district  court.   The district  court

ruled that the arbitrator  exceeded his authority as a  matter of

law by ignoring  plain and unambiguous language  in the contract.

We  review this finding de  novo and make  our own determination,

according  to  the  standards  described above,  of  whether  the

arbitrator's  application of  the contract  was plausible.   See,
                                                                

e.g.,  Upshur Coals Corp. v.  United Mine Workers,  Dist. 31, 933
                                                            

F.2d  225,  228 (4th  Cir. 1991);  Delta  Queen Steamboat  Co. v.
                                                              

District  2 Marine Engs. Beneficial Ass'n, 889 F.2d 599, 602 (5th
                                         

Cir.  1989), cert. denied, 498 U.S. 853 (1990); see also Berklee,
                                                                

858  F.2d  at  32-34   (vacating  district  court's  reversal  of

arbitrator's interpretation  of labor contract  without affording

deference to the district court's findings); Bacard , 692 F.2d at
                                                    

211-14 (implicitly  applying de novo review  in vacating district

court's   finding   that   arbitrator   erroneously   interpreted

collective bargaining agreement).

          B.  The Past Practices Clause
                                       

          With   this   circumscribed   standard  for   reviewing

arbitration awards in  mind, there  is little  question that  the

arbitrator's interpretation of the  Project Agreement -- at least

                               -9-

to the extent  that he found that the  past practices clause bars

consideration of the plaintiffs' evidence of prior fringe benefit
                               

arrangements  -- must  be upheld  as a  plausible reading  of the

contract.   This  result  is compelled  because the  arbitrator's

holding comports with the  district court's own interpretation of

the past practices clause  when properly applied to the  facts of

this case.  Thus,  even if the arbitrator exceeded  his authority

in finding that the  past practices clause wiped the  slate clean

of  all established practices between all parties, an issue we do

not decide, he certainly  did not exceed his authority  by wiping

the  slate clean  between the  Union and  the plaintiffs  in this

particular case.

          The  district court  apparently failed to  consider the

possibility that plaintiffs in this case are  "other parties" and

therefore not  privy to  the past  practice  of excluding  owner-

operators  from the payment of fringe benefits.  According to the

district  court,  the  plain   language  of  the  past  practices

provision  in the  preamble provides  merely that  past practices

established between parties A and B shall not be binding on party

C,  although  they  will  continue  to  be  binding  on  A and  B

themselves.   Applying  this interpretation  to the  present case

reveals that fringe benefit practices between the Union and other

employer-contractors (parties  "A" and "B" respectively)  are not

binding on the plaintiffs (both party "C's"), who did not have an

established  past practice with the Union and are thus "any other

parties"  under  the past  practices clause.    As a  result, the

                               -10-

contract  could be  read  to  require  the arbitrator  to  ignore

evidence of  past practices between  the Union and  other parties

when applying the provisions of the Project Agreement to disputes

between   the  Union  and  the   plaintiffs.    Because  such  an

interpretation is a plausible one,  we must reverse the  district

court's vacation  of the arbitration  ruling with respect  to the

arbitrator's construction of the Project Agreement.

          The plaintiffs  take issue with such  an application of

the past practices clause to the  facts of this case.  They argue

that because the  Union itself was privy  to the practice  of not

requiring fringe benefit payments for owner-operators,  the Union

can still be  held to that practice, regardless  of the fact that

plaintiffs  cannot  in  any way  be  bound  by  such a  practice.

Plaintiffs point to the language of the clause, which states that

"[n]o practice . . . between a Contractor and a Union party . . .

shall be  binding on any other  party," to argue that  the clause

itself concerns only the effects of past practices on new parties

to the project agreement but in  no way limits the effect of past

practices on the Union itself.

          The plaintiffs' interpretation is certainly reasonable,

but, for  our purposes, it  is also irrelevant.   Our task  is to

determine  whether  the  arbitrator  exceeded  his  authority  by

failing to apply the contract in a plausible manner, not to  seek

out the  most reasonable meaning  of the contract.   Interpreting

the  past practices  clause to  bar consideration  of plaintiffs'

evidence of past practice in this case is clearly plausible.  The

                               -11-

clause  can be  read to preclude  application of  all established

past practices to "any  other party," even if that practice is in

the  "other party's" favor.   Such  a reading  stems from  one of

several plausible  constructions of  the language in  the clause:

(1) no practice between parties A  and B shall be binding between

parties  A and  C;  (2) practices  not  binding  on party  C  are

likewise unavailable to C for use against parties A or B (i.e., C

is not  entitled to rely on  or benefit from a  practice which is

not  binding on  itself); and  (3) no  practice shall  be binding

unlessalreadyestablished betweenaUnion andaparticular contractor.

          In this case, the  arbitrator could plausibly find that

the practice  of excluding fringe  benefits for  owner-operators,

established  between  the Union  and  other  contractors, is  not

binding between the Union and the plaintiffs.  Alternatively, the

arbitrator  could find  that plaintiffs  cannot benefit  from the

past fringe benefit  practice because each  plaintiff is an  "any

other party"  and thus could not be bound by the practice were it

beneficial to the Union instead of to the employer.

          Plaintiffs  protest  that  we  cannot  now  employ such

reasoning to  retroactively  salvage an  otherwise  unsustainable

arbitration  award.   They  point out  that  even if  the Union's

interpretation  of the  past practices  clause is  plausible, the

arbitrator  did not  arrive at  that interpretation  himself, but

instead,  arrived at  an  interpretation that  ignored the  plain

language of the  contract.   The arbitrator found  that the  past

practices clause wiped  the slate clean of all  practices between

                               -12-

all  parties, not  just  practices between  parties  A and  C  as

discussed  above.    The  arbitration  award  cannot  be  upheld,

plaintiffs argue,  on  the  basis  of an  interpretation  of  the

contract  that the arbitrator did not even make, because, in this

case  at least,  the arbitrator  might have  come to  a different

conclusion  as  to  whether   past  practice  evidence  could  be

considered if  he adopted the district  court's interpretation of

the past practices clause at the time of his decision.

          We  see  no  problem with  upholding  the  arbitrator's

decision on  grounds or reasoning not employed  by the arbitrator

himself.  To begin with, an arbitrator  has no obligation to give

his  or her  reasons for  an  award.   Raytheon Co.  v. Automated
                                                                 

Business Sys., 882 F.2d 6, 8 (1st Cir. 1989).  Once an arbitrator
             

chooses to provide such reasons,  courts should upset the  award,

or remand  for clarification,  only when  "the  reasons that  are
                                                                 

given strongly imply that the arbitrator may have exceeded his or

her authority."   Randall v.  Lodge No. 1076,  648 F.2d  462, 468
                                            

(7th  Cir. 1981); see also Cannelton Indus. v. District 17, UNWA,
                                                                

951  F.2d  591,  594  (4th  Cir.  1991)  (remanding  portion   of

arbitration award because  it may have  been based on a  grant of

punitive, as opposed to compensatory, damages, in which  case the

award did not  draw its  essence from  the contract).   Absent  a

strong  implication  that  an  arbitrator  exceeded  his  or  her

authority,  the arbitrator is presumed  to have based  his or her

award on proper grounds.  Saturday Evening Post Co. v. Rumbleseat
                                                                 

Press,  Inc., 816  F.2d  1191, 1197  (7th  Cir. 1987);  see  also
                                                                 

                               -13-

Chicago  Newspaper  Publishers'  Ass'n v.  Chicago  WEB  Printing
                                                                 

Pressman's Union, 821 F.2d 390, 394-95 (7th Cir. 1987) ("'[i]t is
                

only when the arbitrator must  have based his award on some  body
                             

of thought,  or feeling, or  policy, or law  that is outside  the

contract  . .  . that  the award  can be  said not  to  'draw its

essence  from the  collective bargaining  agreement.''") (quoting

Ethyl Corp. v. United  Steelworkers, 768 F.2d 180, 185  (7th Cir.
                                   

1985)) (emphasis in original).

          In  this  case,   despite  the  arbitrator's  allegedly

erroneous reasoning, there is  nothing to indicate the arbitrator

exceeded his  authority by  not "arguably construing  or applying

the contract."   Misco, 484  U.S. at 38;  see General  Teamsters,
                                                                 

Auto Truck Drivers &amp;  Helpers, Local 162 v. Mitchell  Bros. Truck
                                                                 

Lines,  682 F.2d 763  (9th Cir.  1982) (upholding  arbitrator for
     

"doing  the right thing for the wrong reason").  The arbitrator's

interpretation of the  past practices clause  in the preamble  as

precluding  the  use of  past  practice  evidence in  determining

plaintiffs'   obligations  under  the   Project  Agreement  is  a

plausible  interpretation of  the contract and  as such,  must be
                                                              

upheld.    El  Dorado,  961  F.2d at  319.    The  fact  that the
                     

arbitrator's  "wipe-the-slate-clean"  construction  of  the  past

practices clause might indicate  that the arbitrator exceeded his

authority  if he had  applied that construction  to other parties

not  present in this litigation does not  mean that he might have

exceeded  his authority in this particular case.  Rather, we know

the  arbitrator   did  not  exceed  his   authority  because  his

                               -14-

application of the past practice clause to the plaintiffs' claims

drew  its  essence  from  the  collective  bargaining  agreement.

Therefore, we  need not speculate  how the arbitrator  might have

resolved  this  case  had  he  considered  the  district  court's

construction of the contract language at issue.

          C.  Section 302 of the LMRA
                                     

          Unlike  the  dispute  over the  Project  Agreement, the

issue  of whether fringe  benefit contributions on  behalf of the

owner-operators is illegal under federal law does not involve the

same  type  of  circumscribed  judicial  review  that  we  afford

arbitration decisions grounded in interpretations of  a contract.

Although the  arbitrator's factual findings  regarding the status

of the owner-operators under Section 302 of the LMRA, 29 U.S.C.  

186,  may deserve  a certain  amount of  deference, the  issue of

illegality is  ultimately one for  federal court review.   Misco,
                                                                

484 U.S. at 42-43.  Given that a determination under    302 could

have  criminal  consequences, the  plaintiffs deserve  a thorough

judicial review of an arbitrator's decision as to this issue.

          Neither party disputes that the plaintiffs' payment  of

fringe benefits on behalf of the owner-operators is illegal under

  302  if the owner-operators are  independent contractors rather

than employees.  The parties do disagree, however, on whether the

issue was properly decided by the arbitrator and, if not, how the

issue  should now  be resolved.   The  plaintiffs argue  that the

arbitrator did not properly decide the issue and  that we, or the

district  court,   should  find  that   the  owner-operators  are

                               -15-

independent contractors, effectively  nullifying the  arbitration

award.  The Union argues that the arbitrator correctly found that

the owner-operators were employees and that we should uphold this

finding.

          The  arbitrator  did,  at  the  very  least, implicitly

decide  the    302 issue  by granting  an award  in favor  of the

Union.    However,  we  are  not satisfied  that  the  arbitrator

conducted  the  appropriate  statutory analysis  for  making  the

required  factual determination  of the  owner-operator's status.

Distinguishing  between employees and independent contractors for

purposes  of the LMRA is governed by general principles of agency

law.  National Labor Relations Bd. v. Amber Delivery Serv., Inc.,
                                                                

651  F.2d 57,  60 (1st  Cir. 1981).   Courts  have spelled  out a

number of factors to be considered in making the determination of

a  party's status,  including various  indicia of  the employer's

"right  to control" certain aspects of that party's work.  Amber,
                                                                

651 F.2d at 61; Construction, Bldg. Material, etc., Local No. 221
                                                                 

v. National Labor Relations  Bd., 899 F.2d 1238, 1240  (D.C. Cir.
                                

1990); North Am. Van Lines, Inc.  v. N.L.R.B., 869 F.2d 596, 599-
                                             

600 (D.C. Cir.  1989); H. Prang  Trucking Co. v. Local  Union No.
                                                                 

469, 114 L.R.R.M. 3617 (D.N.J. 1983).  Although the intent of the
   

parties when they  entered into a contractual relationship may be

relevant  to determining an  employer's "right to  control" or to

other  aspects of  the agency  test, no  one factor  is decisive.

Todd  v. Benal Concrete  Constr. Co, 710 F.2d  581, 584 (9th Cir.
                                   

1983),  cert. denied, 465 U.S. 1022 (1984); Amber, 651 F.2d at 61
                                                 

                               -16-

(citing  N.L.R.B. v. United Ins.  Co, 390 U.S.  254, 258 (1968)).
                                    

Rather,  all of  the incidents  of the  relationship between  the

employer and the alleged  employee must be assessed.   Amber, 651
                                                            

F.2d at 61.

          Given  the arbitrator's  exclusive  focus on  the  past

practices issue  and on provisions  of the contract  dealing with

fringe  benefit contributions,  we have  serious doubts  that the

arbitrator actually conducted a proper   302 agency test analysis

in this case.  There is no  reason to believe, as the Union seems

to  suggest, that  the arbitrator's  decision regarding  the past

practices clause, which we uphold in this opinion, is dispositive

not only of the underlying contractual dispute, but of the    302

issue as well.  Past practices are only one facet of the complete

agency  test  under      302.    Consequently,  the  arbitrator's

discussion  of  the  Project Agreement  and  the  import  of past

practices concerning  the owner-operators, while relevant  to the

parties'  intended working relationship and thus to the status of

the owner-operators  in this  case, is  not itself  sufficient to

convince  us that  a  complete    302  agency test  analysis  was

undertaken.   We  cannot,  therefore, defer  to the  arbitrator's

implicit factual finding on the owner-operators' status to uphold

the arbitration award  until a  more complete    302 analysis  is

conducted.

          We are not prepared,  however, to conduct that analysis

ourselves without first giving  the arbitrator the opportunity to

reexamine  the factual  circumstances of  this case.   Plaintiffs

                               -17-

asserted  in  their action  before  the district  court  that the

arbitration award  is unenforceable  because it  violates federal

law.   The district court  declined to review  this claim because

the  court vacated  the arbitration  award on  the issue  of past

practices.  Because we now  reverse the district court's  ruling,

we are left with plaintiffs'   302 allegations, which have yet to

be properly adjudicated.   In  turn, we are  not disposed  toward

making  factual findings in the first instance, given the absence

of  explicit factual  findings  from the  district  court or  the

arbitrator, that  are required for a proper  determination of the

owner-operators'  status.    Although  a  largely  uncontradicted

record exists in  this case that would allow us  to resolve the  

302 issue if we  needed to, we consider ourselves too far removed

from the dispute to properly  weigh the various factors  involved

in this  fact-intensive determination.  In other words, we refuse

to uphold the arbitrator's finding because plaintiffs have raised

a claim meriting  federal judicial  review yet we,  as a  federal

appeals court, are  not in  a suitable position  to conduct  that

review.

          Unfortunately,  the  district  court  is  in  the  same

position that we are in with respect to determining the status of

owner-operators.   Consequently,  we decline  to remand  the case

directly to  the district  court for a  resolution of  the    302

issue.  The district court itself chose to remand the proceedings

instead of deciding the merits of the case and we think it is the

court's prerogative to  do so.   Although federal  courts have  a

                               -18-

duty to  scrutinize such  federal issues with  potential criminal

consequences,  the  arbitrator  can  play an  important  role  in

providing  first-hand factual  findings  for the  benefit of  the

reviewing  court.     Therefore,  we  remand  this  case  to  the

arbitrator for  a  separate determination  of the  status of  the

owner-operators under   302.

          The plaintiffs  do not dispute our  authority to remand

actions   to  the   arbitrator;   however,  they   claim  it   is

inappropriate to do so when the issue on remand is one of federal

law.   We disagree with their contention that it is inappropriate

for an arbitrator to apply federal statutes.  On the contrary, it

is well established that certain statutory claims may  be decided

through arbitration.    See  Gilmer  v.  Interstate/Johnson  Lane
                                                                 

Corp., 500  U.S.  20, 26  (1991);  Page v.  Moseley,  Hallgarten,
                                                                 

Estabrook &amp; Weeden, Inc., 806 F.2d  291, 295 (1st Cir. 1986).  We
                        

see no reason why the arbitrator cannot make the factual findings

necessary  to resolve the   302  issue in this case.  Determining

the   status  of  owner-operators   is  particularly  within  the

arbitrator's domain  since it involves  analyzing various aspects

of  the  working  relationship  between  the  parties.    Such  a

determination  involves consideration  of precisely  the  type of

issues  that  the parties  originally  agreed  to  refer  to  the

arbitrator under the arbitration clause of the Project Agreement.

We  do, nevertheless,  retain jurisdiction  so that  the district

court can review  the final determination  of the arbitrator,  if

requested to do so by one of the parties.

                               -19-

          On remand,  we expect  the arbitrator will  conduct the

appropriate  agency test  analysis as  described in  the relevant

caselaw.   See, e.g.,  Amber,  651 F.2d at 60-61;  Local No. 221,
                                                                

899 F.2d  at 1240;  North Am.  Van  Lines, 869  F.2d at  599-600;
                                         

Prang, 114 L.R.R.M. at 3617-19; see also  Restatement (Second) of
                                        

Agency    220 (1957).   We leave it  to the arbitrator  to decide

what effect, if  any, the  past practices clause  of the  Project

Agreement  and  the  evidence  of  past  practice  regarding  the

treatment  of owner-operators  has  on his  determination of  the

owner-operators' status  under    302.   Although  we upheld  the

arbitrator's   interpretation   of   the   contract   as  barring

consideration   of  past   practices  in   resolving  contractual

disputes,  we express no opinion on how the past practices clause

in  the contract and the  evidence of past  practices figure into

the various  factors enumerated  under the  agency  test used  to

ascertain a party's status under   302.

          Accordingly,  we reverse the  district court's judgment
                                                                 

vacating  the  arbitration award  and  remand  this case  to  the
                                                                 

district  court with  instructions  to  remand  the case  to  the
                                                                 

arbitrator for further proceedings consistent with this opinion.
                                                               

                               -20-
