II. Defenses and Exceptions to Liability
A. Statutory Defenses
Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA or “Superfund ”)
§107(a) liability is “notwithstanding any other provision or rule of law and subject only to the defenses set
forth in the statute.” Section 107(b) of CERCLA sets forth three armative defenses: act of God, act of
war, and act of third part y.1 Proving these defenses can be challenging. A defendant must show that the
release of the hazardous substa nce was caused solely by a n act of God, war, or third pa rty.2 Further, all of
these defenses are narrowly construed.3 A nd because CERCLA generally imposes strict liability, defenses
based on an absence of negligence or on the use of due care are unavailing,4 a lthough these considerations
may be relevant to the allocation of liability.5
e act of God defense6 has been invoked with little success. is lack of success is hardly surprising, as
CERCLA denes “act of God” as “an unanticipated grave natural disaster or other natural phenomenon of
an exceptional, inevitable, and irresistible character, the eects of which could not have been prevented or
avoided by the exercise of due care or foresight.”7 Accordingly, courts have rejected the act of God defense
in cases of w inter storms,8 unprecedented cold spells,9 hurrica nes,10 and heavy rains a nd oods.11 Defen-
dants invoking the act of God defense have fa red better when pairing it with other armative defenses.12
Similarly, the act of war defense13 typically has been met with little success.14 However, this defense became
newly relevant in the wake of the September 11, 2001, terrorist attacks by Al-Qaeda in New York City. In
Westfarm Assocs., LP v. W
ash. Suburban Sanitary Comm’n, 66 F.3d 669
, 677 (4th Cir. 1995) (noting CERCLA’
s “narrow defenses”); Gen.
Elec. Co. v
. AAMCO T
ransmissions, Inc., 962 F.2d 281
(2d Cir. 1992); N.Y
. State Elec. &
Gas Corp. v.
FirstEnergy Corp., 808 F. Supp.
4. See, e.g.
, United States v. Capital T
ax Corp., 545 F.3d 525
, 530 (7th Cir. 2008) (“CERCLA is strict liability statute.”); Canadyne-Ga. Corp.
v. NationsBank, NA, 183 F.3d 1269
, 1275 (11th Cir. 1999) (“CERCLA does not allocate liability based on fault or negligence; it is a strict
United States v
wp. of Brighton, 153 F.3d 307
, 318 (6th
Cir. 1998); Control Data Corp
. v. SCSC Corp., 53 F.3d 930
, 936 (8th Cir. 1995);
aler v. PRB Metal Prods., I
nc., 815 F. Supp. 99
(E.D.N.Y. 1993); Kramer
, 757 F
. Supp. at 422; United S
tates v. Conservation Chem. Co.,
7. Id. §9601(1).
8. United States v. Sterling Centrecorp, Inc., No. 2:08-CV-02556, 2011 WL 6130891, at *5–6 (E.D. Cal. Dec. 8, 2011) (partial collapse of log
dam during winter storm was not act of God because it was neither exceptional nor utterly unforeseeable).
United States v
. Barrier Indus.,
Inc., 991 F. Supp. 678
, 679–80 (S.D.N.Y.
cold spell” did not fall
within the act of
defense, but even if it did, there was no evidence that the hazardous release or threat of release was caused solely by the cold spell).
United States v. Alcan Aluminum Corp., 892 F. Supp. 648
, 658 (M.D. Pa. 1995) (hurricane did not fall within act of God defense because
it was not the sole cause of the hazardous release, the eects could have been mitigated by the exercise of due care, and hurricane was not the
sort of “exceptional” natural phenomenon to which the defense applied).
Inc., 809 F. Supp. 959
, 969 (M.D.
Ga. 1992) (ood was
not act of
God because it
occurred after cleanup was
in progress); United States v. Stringfellow, 661 F. Supp. 1053
, 1061 (C.D. Cal. 1987) (heavy but foreseeable rains are not contemplated by
the term “act of God”).
United States v
Inc., 951 F. Supp. 1518
1531 (D. Nev
. 1996) (rejecting defendant’
s act of
God defense standing alone but
that, in combination with allegations regarding the acts of a third party, evidence of act of God defense created material disputed issue of fact).
Section 107(b) specically permits armative defenses to be combined with one another. 42 U.S.C. §9607(b)
For example, the Ninth Circuit in United States v. Shell Oil Co., 294 F.3d 1045 (9th Cir. 2002), rejected the act of war defense invoked by oil
companies in a suit regarding the disposal of hazardous substances created by the production of aviation fuel during World War II. Although
the government exercised signicant control over the means of aviation fuel production during a time of war, the defense was to be construed
narrowly, and the government did not compel the companies to dispose of their waste in any particular manner. Id. at 1062.