                         RECOMMENDED FOR FULL-TEXT PUBLICATION
                              Pursuant to Sixth Circuit Rule 206
                                      File Name: 09a0152p.06

                 UNITED STATES COURT OF APPEALS
                                  FOR THE SIXTH CIRCUIT
                                    _________________


                                                X
                                                 -
 U.S. BANK NATIONAL ASSOCIATION,

                         Plaintiff-Appellant, --
 TRUSTEE,

                                                 -
                                                      No. 08-3083

                                                 ,
                                                  >
                                                 -
           v.

 U.S. ENVIRONMENTAL PROTECTION AGENCY, -
                        Defendant-Appellee. -
                                                 -
                                                N
                  Appeal from the United States District Court
                 for the Southern District of Ohio at Cincinnati.
               No. 07-00670—Sandra S. Beckwith, District Judge.
                                    Argued: March 12, 2009
                              Decided and Filed: April 20, 2009
                                                                                               *
      Before: MARTIN and GILMAN, Circuit Judges; ZOUHARY, District Judge.

                                      _________________

                                           COUNSEL
ARGUED: Pierre H. Bergeron, SQUIRE, SANDERS & DEMPSEY, L.L.P.,
Cincinnati, Ohio, for Appellant. Anna T. Katselas, UNITED STATES DEPARTMENT
OF JUSTICE, Washington, D.C., for Appellee. ON BRIEF: Pierre H. Bergeron,
Thomas D. Amrine, Scott A. Kane, SQUIRE, SANDERS & DEMPSEY, L.L.P.,
Cincinnati, Ohio, for Appellant. Anna T. Katselas, UNITED STATES DEPARTMENT
OF JUSTICE, Washington, D.C., for Appellee.




        *
           The Honorable Jack Zouhary, United States District Judge for the Northern District of Ohio,
sitting by designation.


                                                  1
No. 08-3083             U.S. Bank National Association v. U.S.                                     Page 2
                        Environmental Protection Agency


                                         _________________

                                               OPINION
                                         _________________

        BOYCE F. MARTIN, JR., Circuit Judge. Eagle-Picher Technologies, LLC1
(“EP Tech”), an electronics manufacturer, filed for Chapter 11 bankruptcy in 2005. The
United States, on behalf of the Environmental Protection Agency and the Department
of Interior, filed a claim in the bankruptcy proceeding against EP Tech under
“CERCLA”—the Comprehensive Environmental Response, Compensation and Liability
Act of 1980. Under CERCLA, the federal government may recover the cost of cleaning
up hazardous waste from the parties responsible for its release.

        Over the objections of U.S. Bank, the bankruptcy trustee, the bankruptcy court
found EP Tech liable for $357,246 of already-incurred costs and $8,735,434 in estimated
future costs for the clean-up of groundwater and soil contamination near a now-vacant
manufacturing plant in Socorro, New Mexico. U.S. Bank appealed to the district court,
which affirmed.

        U.S. Bank appeals to this Court, arguing: (i) EP Tech is not liable under
CERCLA for hazardous waste releases that occurred before EP Tech acquired an interest
in the Socorro plant in 1998; (ii) even if EP Tech is liable for the clean-up costs at the
plant, genuine issues of material fact precluded the bankruptcy court from concluding
that EP Tech was responsible for contamination detected at a well located a mile and a
half south of the plant; and (iii) the bankruptcy court improperly excluded evidence at
the hearing on estimating the future cost of cleaning up the hazardous substances. The
bankruptcy court’s decision was legally correct, and it did not abuse its discretion by
excluding evidence of future costs. We AFFIRM.




        1
            The record alternatively spells this “EaglePicher,” “Eagle-Picher,” and “Eagle Picher.” We will
use “EP.”
No. 08-3083          U.S. Bank National Association v. U.S.                                Page 3
                     Environmental Protection Agency


                                                I.

                    A. EP Tech and the Socorro manufacturing plant

        EP Tech was incorporated in 1998. That year it acquired one of EP Industries,
Inc.’s (“EP Inc.’s”) internal divisions2—the Technologies Division—via an Assignment
and Assumption Agreement. Per this 1998 Agreement, EP Tech acquired: “[a]ll real
property and all leasehold interests in real property used in connection with the
Business” along with “[a]ll written or oral contracts, agreements or other arrangements
relating to the Business.” Among these thirty-seven real property interests was a
leasehold interest in “Highway I-25, Exit 152 Socorro, NM 87801 (Vacant Plant).”

        As it turned out, the Socorro manufacturing plant had a checkered past when it
came to waste disposal. In 1963, EP Inc. began manufacturing water-activated batteries,
printed circuit boards, and cable connectors at the plant, located on about 170 acres due
north of Socorro. The manufacturing process involved trichlorethylene or “TCE”—a
cleaner that was discharged into floor drains connected to an onsite sewage lagoon.
TCE, according to the World Health Organization, is “probably carcinogenic to
humans,” and has been designated a hazardous substance for purposes of CERCLA
liability. 40 C.F.R. § 302.4.

        In 1976 the company stopped its manufacturing operation and deeded the
property surrounding the plant back to the city which, from 1977 to 1980, used a portion
of the property as a municipal landfill. But in 1979, the company leased part of the
property back from the city and started to manufacture lead-acid batteries at the Socorro
plant, a process that generated liquid and solid waste but, according to EP Tech, not TCE
waste. The lease ended in 2000, by which time the plant was no longer in use.




        2
          According to U.S. Bank, until 1969 this entity was known as “EaglePicher Company” but was
later renamed “EaglePicher Incorporated.” We refer to this entity as “EP Inc.”
No. 08-3083          U.S. Bank National Association v. U.S.                                Page 4
                     Environmental Protection Agency


                            B. Hazardous substances in the area

        In 1987 a well at the manufacturing plant, the Eagle Picher Municipal Well,
tested positive for TCE, and the nearby soil tested positive for lead. By 1990 TCE was
detected in the Olson Well,3 a municipal well located about a mile and a half south of
the Socorro plant. In response, the EPA and the New Mexico Environment Department
began investigating the contamination source. A 1989 investigation of the landfill
concluded that it was not the contamination source.

        Despite the TCE detected in both the Olson Well and at the plant, investigations
in the 1990s and early 2000s did not find a link between the TCE contamination at the
Olson Well and the plant’s waste disposal practices. Notably, in 1996, the New Mexico
Environment Department conducted an “Expanded Site Inspection” that involved
sampling well-water. Wells at the plant and the Olson Well tested positive for TCE, but
the residential wells in between the two did not. The investigators reasoned:

        Whether the release to the Olsen Well can be attributed to the Eagle
        Picher facility is questionable because the Olsen Well is located 1.5 miles
        from the Eagle Picher facility and because TCE was not detected in the
        residential wells (Gonzalez and Cotton) located between the Eagle Picher
        facility and the Olsen Well. Therefore, the release of TCE and DCE in
        the Olsen Well is not attributed to the sources on-site at this time. If
        more information regarding the sources associated with the release in the
        Olsen Well is available in the future, attribution of the release shall be
        reevaluated.
        But by the time the United States moved for partial summary judgment in late
2006, a third party, under contract with the U.S. Army Corps, had completed two years
of investigating contaminants around Socorro.              The study included drilling new
monitoring wells and taking surface water and sediment samples from 2004 through
2006. Unlike the earlier investigations, this more recent round of tests detected TCE in
several private residential wells between the Eagle Picher Municipal Well and the Olson
Well. It led to an April 2007 expanded site inspection and remedial investigation report

        3
           Sometimes spelled “Olsen Well.” For consistency, we adopt “Olson Well” throughout but do
not alter spelling changes in direct quotes.
No. 08-3083         U.S. Bank National Association v. U.S.                         Page 5
                    Environmental Protection Agency


concluding that TCE “in the Socorro area can be attributable to the former EaglePicher
facility . . . .” This report stated that “[e]xisting monitoring wells in the project area
indicate that the groundwater gradient is to the south . . . and that a groundwater plume
containing chlorinated organic contaminants extends from the former Eagle Pitcher [sic]
property to the Olsen well,” and “[t]he TCE and other chlorinated organic compound
contamination of groundwater in the Socorro area can be attributable to the former Eagle
Picher facility based on the historic use and disposal of TCE at the former Eagle Picher
facility, the absence of TCE up gradient of the facility, the hydrogeology of the Socorro
area, the lack of evidence for other TCE sources, and the characteristics of chlorinated
solvents.”

       In September 2007, the EPA issued a final rule placing the Socorro site on its
Superfund National Priorities List—the list of hazardous waste sites designated for
priority cleanup.    The report describes a large “plume” of TCE-contaminated
groundwater approximately two miles long and a quarter-mile wide that extends from
the manufacturing plant to an area including the Olson Well.

               C. EP Inc.’s 1991 bankruptcy and settlement agreement

       The bankruptcy at issue here is not the first for the EP businesses. And the
Socorro plant is not the only location where an EP entity released hazardous waste.
Thus, when EP Inc. filed for Chapter 11 bankruptcy in 1991, the United States filed a
claim for the EPA’s costs incurred and to be incurred “in the course of responding to
releases and threatened releases of hazardous substances into the environment from
certain sites. . . .” The United States and EP Inc. executed a settlement agreement in
1996—the “1996 Bankruptcy Settlement Agreement,”—which obligated EP Inc. and
“any successor or assign” to be accountable for environmental liabilities at twenty-four
sites (not including Socorro) and at “[a]dditional [s]ites.” The Socorro site qualifies as
an “additional site” because it was not listed as a “liquidated site” or a “debtor-owned
site” under the 1996 Bankruptcy Settlement Agreement. The Agreement also specified
that payment for environmental response costs at “additional sites” would be subject to
No. 08-3083        U.S. Bank National Association v. U.S.                          Page 6
                   Environmental Protection Agency


the distribution terms of the bankruptcy reorganization plan—which amounted to a
distribution rate of 37%, or $0.37 per $1.00 for general unsecured creditors.

                            D. EP Tech’s 2005 bankruptcy

       This appeal arises out of EP Tech’s 2005 Chapter 11 bankruptcy, filed
concurrently with that of its parent corporation, EP Holdings Inc.            Under the
reorganization plan, the debtors’ assets were transferred to the EP Custodial Trust with
U.S. Bank as trustee. The United States filed a claim on behalf of the EPA and the
Department of the Interior against EP Tech seeking to recover the costs for responding
to the contamination in the area around the Socorro manufacturing facility, including the
Olson Well. U.S. Bank objected on the ground that EP Tech did not assume liability for
hazardous waste releases that occurred before it was incorporated in 1998. In 2007, the
bankruptcy court granted the EPA’s motion for partial summary judgment as to EP
Tech’s liability for response costs, finding that EP Tech assumed, under the 1998
Agreement with EP Inc., all of EP Inc.’s environmental liabilities relating to the Socorro
facility. The bankruptcy court further rejected EP Tech’s argument that it was not liable
for the contamination at the Olson Well under CERCLA. The EPA established past
costs of $965,530.54, which, at a rate of 37% per the 1996 Bankruptcy Settlement
Agreement, amounts to $357,246.

       The bankruptcy court held an estimation hearing on EPA’s future response costs,
which it found amounted to $23.6 million, reduced to 37%, or $8,735,434. EP Tech
appealed this finding to the district court, which affirmed the bankruptcy court’s orders.
EP Tech now appeals.

                                           II.

       When reviewing a bankruptcy court order on appeal from a decision of a district
court, this Court “review[s] the bankruptcy court’s order directly and give[s] no
deference to the district court's decision.” In re Lee, 530 F.3d 458, 463 (6th Cir. 2008).
No. 08-3083        U.S. Bank National Association v. U.S.                            Page 7
                   Environmental Protection Agency


The bankruptcy court’s findings of fact are reviewed for clear error, and its conclusions
of law are reviewed de novo. Id.

                                           III.

           A. The bankruptcy court did not err in concluding that EP Tech
                assumed its predecessor’s environmental liabilities

       The parties’ threshold disagreement is whether the 1998 Agreement between EP
Inc. and EP Tech assigned to EP Tech the liability for all hazardous substance disposal
at the Socorro manufacturing facility or only liability arising after the Agreement’s
execution date—February 24, 1998. The bankruptcy court decided that EP Tech
expressly assumed all of EP Inc.’s environmental liabilities, including liability for
“additional sites” like Socorro under the 1996 Bankruptcy Settlement Agreement with
the EPA.       Successor liability under CERCLA is determined by common law
contract principles. Mickowski v. Visi-Trak Worldwide, 415 F.3d 501, 515 (6th Cir.
2005). Under Ohio law (which the parties agree governs the 1998 Agreement) a buyer
of corporate assets is not liable for the debts and obligations of the seller, Flaugher v.
Cone Auto. Mach. Co., 507 N.E.2d 331, 334 (Ohio 1987), unless it assumes such
liability “expressly or impliedly.” Id. at 334.

       Here, the language of the 1998 Agreement and Assignment undermines U.S.
Bank’s contention that EP Tech assumed liabilities arising only after the date of
execution. The second paragraph of the Agreement states:

       The Assignor has agreed, among other things, to assign to the Assignee
       all of the Assignor’s right, title and interest in the properties, assets
       (tangible or intangible) and rights (the “Contributed Property”) of the
       Assignor’s Technologies Division (the “Business”) which are more
       particularly set forth on Annex A hereto, and the Assignee has agreed
       that it will accept such assignment and will assume all of the liabilities
       and obligations of the Assignor with respect to the Business (collectively,
       the “Obligations”);
(emphasis added). The Agreement further describes EP Tech’s assumptions in the
second numbered paragraph:
No. 08-3083         U.S. Bank National Association v. U.S.                           Page 8
                    Environmental Protection Agency


       2. The Assignee accepts such assignment, and assumes and agrees to
       perform, pay, discharge and comply with all of the covenants, conditions,
       agreements, terms, obligations and restrictions to be performed or
       complied with on the part of the Assignor under or in connection with the
       Business or the Obligations arising from and after the date hereof,
       subject to the covenants, conditions, agreements, terms, obligations,
       restrictions and other provisions set forth in the Contributed Property and
       the Obligations.
(emphasis added).
       U.S. Bank focuses on the phrase, “Obligations arising from and after the date
hereof” to argue that EP Tech assumed only post-agreement liabilities. But this reading
ignores EP Tech’s express assumption of “all of the liabilities and obligations of the
Assignor”—defined collectively as “Obligations.” In the same sentence that EP Tech
agreed to assume “Obligations arising from and after the date hereof,” (“Obligations”
being a defined term) it also agreed “to perform, pay, discharge and comply with all the
covenants, conditions, agreements, terms, obligations and restrictions to be performed
or complied with on the part of the Assignor under or in connection with the
Business . . . .” (emphasis added). The two clauses are separated by the disjunctive,
“or,” meaning that the “after the date hereof” language is a separate source of liability
from liability for EP Inc.’s “obligations” and “agreements.” Indeed, liability under the
1996 Settlement Agreement is an “obligation” “in connection with the Business.”

       Although the Agreement is not a model of good draftsmanship, EP Tech
expressly and separately assumed “all” “obligations” and “agreements” “in connection
with the Business”—which includes the 1996 Bankruptcy Settlement Agreement. Thus,
the plain and unambiguous language of the 1998 Agreement supports the bankruptcy
court’s determination that the 1998 Agreement transferred liabilities “in connection with
the Business,” including those that existed when the Agreement was executed and those
“arising from and after” the execution. We conclude therefore that EP Tech assumed
CERCLA liability that EP Inc. incurred as an owner or operator of a site at the time of
the disposal of hazardous substances. See 42 U.S.C. § 9607(a)(2).
No. 08-3083           U.S. Bank National Association v. U.S.                                     Page 9
                      Environmental Protection Agency


                           B. Size of facility and divisibility of harm

         CERCLA establishes strict liability for “any person who at the time of disposal
of any hazardous substance owned or operated any facility at which such hazardous
substances were disposed of.” 42 U.S.C. § 9607(a)(2). EP Tech argues that even if it
assumed EP Inc.’s liability for hazardous substances disposal at the manufacturing plant,
it is not liable for response costs related to hazardous substances at the Olson Well. The
company maintains that the Olson Well is a “discrete site” from the manufacturing plant
and that a data gap in well-water samples between the plant and the Olson Well leaves
open the question of whether there is a single continuous subterranean plume extending
from the plant to the Olson Well. This argument requires us to consider whether the
contamination at the Olson Well is distinct from the contamination at the manufacturing
plant, or whether the contamination can be reasonably apportioned between EP Tech and
another party.

         Although CERCLA imposes “joint and several” liability on owners and operators
of facilities that release hazardous waste, United States v. Twp. of Brighton (“Brighton”),
153 F.3d 307, 317 (6th Cir. 1998), a party may attempt to limit its CERCLA liability by
raising a causation-based argument that the cleanup costs at a single CERCLA facility
should be divided between it and another responsible party. Id. at 313.4 The phrase
“divisible environmental harm” describes circumstances where CERCLA liability may
be apportioned among responsible parties if a potentially responsible party proves that:
“(a) there are distinct harms, or (b) there is a reasonable basis for determining the
contribution of each cause to a single harm.” Id. at 317-18. The ultimate burden of
proving divisibility is on the party invoking the doctrine. United States v. R.W. Meyer,
889 F.2d 1497, 1507 (6th Cir. 1988).




         4
           The harshness of strict and joint and several liability is mitigated by CERCLA’s provisions
allowing a party who has been sued under Section 107(a) to seek contribution from any other person liable
or potentially liable under CERCLA. Cooper Indus., Inc. v. Aviall Servs., Inc., 543 U.S. 157, 162 (2004)
(describing remedies available under Section 113(f) of CERCLA).
No. 08-3083         U.S. Bank National Association v. U.S.                           Page 10
                    Environmental Protection Agency


         Although other courts have described the divisibility determination as a “question
of law” subject to de novo review, e.g., In re Bell Petroleum Services, Inc., 3 F.3d 889,
902 (5th Cir. 1993), this Court has (curiously) described the inquiry as a “question of
causation,” Brighton, 153 F.3d. at 318, n.13, subject to reversal only if the determination
is “clearly erroneous,” even when reached at the summary judgment stage. R.W. Meyer,
889 F.2d at 1507. Notwithstanding Brighton and R.W. Meyer, we are mindful that here,
in reviewing a decision reached at the summary judgment stage, our task is to determine
whether genuine issues of material fact preclude a pre-trial ruling on the merits. See,
e.g., Tenn. Scrap Recyclers Ass’n v. Bredesen, 556 F.3d 442, 447 (6th Cir. 2009).

              1. Dr. Rees’s report was not properly before the bankruptcy
              court when it ruled on the partial summary judgment motion.

         U.S. Bank argues that the bankruptcy court prematurely decided that the
environmental harm near Socorro was not divisible. As a threshold matter, we must
determine the scope of the record before the bankruptcy court when it ruled on the
United States’s motion for partial summary judgment on liability. We do so because our
role is “to review the case presented . . . rather than a better case fashioned after . . . an
unfavorable order.” See Barner v. Pilkington N. Am., Inc., 399 F.3d 745, 749 (6th Cir.
2005).

         U.S. Bank argues that a report prepared by Dr. Todd H. Rees—filed six days
after the parties fully briefed the partial summary judgment motion, but six days before
the bankruptcy court ruled on the motion—was part of the record when the bankruptcy
court ruled and should have been considered in connection with the liability
determination. As the bankruptcy court explained, however, it did not consider the Rees
report “because it believed the motion to be fully briefed as of January 25, 2007, per the
agreed scheduling order.” Consistent with this schedule, U.S. Bank made no reference
to the Rees report in its brief responding to summary judgment, nor did it otherwise
notify the bankruptcy court that the report was relevant to its opposition to summary
judgment. The bankruptcy court therefore properly limited its consideration to the
record before it on the briefing deadline because it had no reason to know that U.S. Bank
No. 08-3083         U.S. Bank National Association v. U.S.                         Page 11
                    Environmental Protection Agency


intended to rely on its later-filed expert report, filed in connection with the future costs
estimation hearing, to support its opposition to summary judgment. We thus limit our
review of the bankruptcy court’s summary judgment ruling to the record as it stood on
January 25, 2007—which did not include Rees’s expert report.

        After the bankruptcy court ruled that the environmental harm around Socorro was
indivisible, U.S. Bank asked the bankruptcy court to reconsider in light of the Rees
report, which it characterized as “newly discovered evidence.” The bankruptcy court
declined this request, observing that, “[a] motion to consider newly discovered evidence,
even when liberally viewed under Bankruptcy Rule 3008, is not a stopgap for lack of due
diligence or for self-made circumstances.” We agree. “Reconsideration of a claim that
has been previously allowed or disallowed after objection is discretionary with the
court.” FED. R. BANKR. P. 3008 advisory committee’s note. The bankruptcy court did
not abuse its discretion by declining to reconsider its earlier divisibility ruling based on
Rees’s report.

      2. No genuine issue of material fact precluded the bankruptcy court from
             concluding that the environmental harm at the Olson Well
             was not “distinct” from harm at the manufacturing facility.

        U.S. Bank argues that the bankruptcy court should not have ruled on the question
of the divisibility of the environmental damage at the summary judgment stage because
U.S. Bank raised a genuine issue of material fact as to whether the harm at the Olson
Well was “distinct” from the harm at the manufacturing facility. Under CERCLA,
“distinct harms” are “separate injuries.” See Restatement (Second) of Torts § 433A
(1965); Brighton, 153 F.3d at 319 (“The proper standards for divisibility come from the
Restatement (Second) of Torts[.]”).        In Brighton, this Court catalogued several
“reasonable bases for dividing harm,” including “relative toxicity, migratory potential,
degree of migration, and synergistic capacities of the hazardous substances.” 153 F.3d
at 320 (citing United States v. Alcan Aluminum Corp., 990 F.2d 711, 722 (2d Cir. 1993)).
Other courts have recognized “distinct harms” where a site consists of distinct
No. 08-3083        U.S. Bank National Association v. U.S.                       Page 12
                   Environmental Protection Agency


subterranean “plumes” of groundwater contamination. E.g., United States v. Broderick
Inv. Co., 862 F. Supp. 2d 272, 277 (D. Colo. 1994).

       In support of its motion for summary judgment on the issue of liability, the EPA
submitted, among other exhibits, a map of the plume, a declaration from Bret Kendrick,
EPA’s Remedial Project Manager for the Socorro site, and reports from testing for
contamination conducted in 2006. Kendrick’s declaration stated that, after the earlier
inconclusive investigations into the source of TCE contamination at the Olson Well, the
EPA and New Mexico Environment Department:

       have investigated and sampled soil and groundwater at numerous
       locations in the intermediate area between the Eagle Picher Municipal
       Well and the Olson Well. The results of the investigation indicate that
       the TCE contamination originates at the former EaglePicher property and
       that the TCE contamination has migrated south to at least the Olson Well.
       Kendrick also stated that “no source area of TCE release has been identified
within the area of the plume other than at the EaglePicher property.” He interpreted the
available data to indicate that the TCE contamination migrated from the manufacturing
plant at least as far south as the Olson Well. In opposing summary judgment, U.S. Bank
stated that “it appears that there may be reasonable and rational chronological and
volumetric reasons for apportioning the contribution of causes for soil and groundwater
contamination by the primary contaminants of concern, TCE and lead, over periods of
time and between numerous operators.” But it did not timely offer evidence to support
its allegation that the contamination at the Olson Well was distinct from the
contamination at the manufacturing facility.

       U.S. Bank relied on one of the Brighton bases for divisibility, (“relative
toxicity”) to argue that disparities in TCE levels at the Olson Well and at the plant
undermined the EPA’s assertion that there was a continuous indivisible plume extending
from the plant to the Olson Well. But the evidence it offered was insufficient to create
a genuine issue of material fact because the evidence was limited to a quote from the
Socorro City Clerk, contained in the local newspaper that “Recent tests of Eagle Picher
Well showed no TCE.” Yet U.S. Bank made no effort to reconcile this unsupported
No. 08-3083         U.S. Bank National Association v. U.S.                          Page 13
                    Environmental Protection Agency


quote with the 2006 sampling data that the United States submitted to support its motion
for summary judgment. U.S. Bank also cited to the 1996 expanded site investigation that
concluded that the TCE groundwater at the Olson Well could not be connected to EP
Inc. “at [that] time.” But it ignored Kendrick’s declaration describing how more recent
groundwater sampling showed that contamination extended south from EP Tech’s
property. Without more, no reasonable fact-finder could have concluded that the
contamination at the Olson Well was “distinct” from the contamination at the plant.

      3. No genuine issue of material fact precluded the bankruptcy court from
          concluding that there was no “reasonable basis for determining
                 the contribution of each cause to a single harm.”

        The Brighton court also recognized that in some situations even a single harm
may be apportioned where there is a “reasonable basis for determining the contribution”
of multiple causes. 153 F.3d at 318. It acknowledged that “we cannot define for all time
what is a reasonable basis for divisibility and what is not,” id. at 319, but made clear that
“unlike comparative negligence, divisibility analysis is not an invitation to courts to
attempt to ‘split the difference.’” Id. Thus, courts should impose joint and several
liability “unless they have a reasonable basis for dividing causation.” Id.

        Here, besides the untimely Rees report, there was no evidence to suggest a
“reasonable basis” for apportioning liability between EP Tech and an unknown second
source. The allegation that a jewelry company may have used the manufacturing facility
in 1979 and may have released TCE was, standing alone, insufficient to demonstrate a
genuine issue of material fact as to whether there was a “reasonable basis” for
apportionment. And U.S. Bank’s contention that there is a basis for chronological
divisibility between it and its predecessor, EP Inc. also fails because, as discussed in
Section I above, EP Tech expressly assumed liability for EP Inc.’s obligations, including
its environmental liabilities. Thus, even if it could show that EP Inc.’s pre-1998
hazardous releases provide a reasonable basis for apportionment, EP Tech expressly
assumed liability for those obligations when it executed the 1998 Agreement.
No. 08-3083        U.S. Bank National Association v. U.S.                         Page 14
                   Environmental Protection Agency


       In sum, at the summary judgment stage, U.S. Bank failed to introduce evidence
sufficient to create a genuine issue of material fact as to whether the harm at the Olson
Well is “distinct” from that at the manufacturing facility or whether there is a
“reasonable basis” for apportioning liability between it and another party.           The
bankruptcy court therefore properly entered summary judgment in the United States’s
favor with respect to CERCLA liability.

 C. The bankruptcy court did not abuse its discretion by excluding certain evidence.

       Finally, U.S. Bank argues that at the estimation hearing on future clean-up costs
at the Socorro site, the bankruptcy court erred in blocking cross-examination of the
EPA’s expert about the source of contamination. U.S. Bank says the bankruptcy court
also erred by preventing U.S. Bank’s expert (Dr. Rees) from testifying about the
directional flow of groundwater and about the presence of contaminants at the Olson
Well that are not located at the manufacturing facility. We review a bankruptcy court’s
evidentiary admissions or exclusions for abuse of discretion. In re Barrett, 487 F.3d
353, 362 (6th Cir. 2007). In determining future costs, the bankruptcy court retained wide
discretion to admit or exclude evidence. Id. In a claim-estimation hearing, the
bankruptcy court’s task is to “arrive at a reasonable estimate of the probable value of the
claim”—not a mathematical certainty. In re Baldwin-United Corp., 55 BR. 885, 889
(Bankr. S.D. Ohio 1985).

       The difference between the parties’ future cost estimates stemmed from the
number of proposed extraction wells; the EPA’s expert proposed four, and U.S. Bank’s
expert opined that one would be sufficient. At the hearing, the bankruptcy court heard
testimony from both experts (Kendrick and Rees), as well as from the EPA’s rebuttal
witness, Dr. Allen Medine.

       As the bankruptcy court observed, there is considerable overlap between the
causation-based divisibility issue that it decided at the summary judgment stage and
evidence relevant to estimating the cost of cleaning up the area. Indeed, in its written
order the bankruptcy court acknowledged the “procedural peculiarity” resulting from the
No. 08-3083         U.S. Bank National Association v. U.S.                         Page 15
                    Environmental Protection Agency


fact that Rees’s expert report discussing “groundwater flow in great detail” was admitted
for the first time at the estimation hearing, after the issue of EP Tech’s liability for the
entire plume was already determined.

         Our review of the hearing transcript indicates, contrary to U.S. Bank’s
characterization, that the bankruptcy court was well-aware that, notwithstanding the
finality of the divisibility issue, U.S. Bank was allowed to challenge the estimate derived
from EPA’s proposed clean-up strategy. And the transcript shows that the court gave
both parties wide latitude. The court appreciated the overlap between the divisibility
issue and the estimation of future costs, allowing, over the EPA’s objections, several
questions that touched on divisibility because “they may have some relevance beyond
that.” It did not categorically bar questions about the scope of the contamination, and
instead probed each of the experts on how their proposed clean-up plans fit with the
available data. And even if Rees’s opinion as to where the groundwater flowed retained
independent relevance to the question of how best to clean up the site, the bankruptcy
court admitted his entire report, which contained his opinions on groundwater flow and
contaminants at the Olson Well.

         We thus conclude that the bankruptcy court did not abuse its discretion. Nor has
U.S. Bank demonstrated that the exclusion of relevant evidence resulted in substantial
injustice. See, e.g., United States v. Alpine Indus., Inc., 352 F.3d 1017, 1029 (6th Cir.
2003).

                                            IV.

         For the reasons explained above, we AFFIRM.
