UNITED STATES COURT OF APPEALS 

FOR THE TENTH CIRCUIT 

_________________________________ 

CHARLES BRYER, 

 Plaintiff - Appellant, 

v. 

CONOCOPHILLIPS, CO.; 

PHILLIPS 66, CO., 

 Defendants - Appellees. 

No. 17-6114 

(D.C. No. 5:15-CV-01218-HE) 

(W.D. Okla.) 

_________________________________ 

ORDER AND JUDGMENT*

_________________________________ 

Before BACHARACH, MURPHY, and McHUGH, Circuit Judges. 

_________________________________ 

This appeal involves an issue of timeliness. The plaintiff, Mr. 

Charles Bryer, lived near an oil refinery that emitted a chemical known as 

benzene. Years later, he was diagnosed with a form of leukemia known as 

Acute Myeloid Leukemia. 

Mr. Bryer sued the owner of the refinery, ConocoPhillips, for 

negligence, negligence per se, and strict liability. But he waited to sue 

until roughly nine years after his diagnosis. Because a two-year limitations 

 

*

 This order and judgment does not constitute binding precedent except 

under the doctrines of law of the case, res judicata, and collateral estoppel. 

But the order and judgment may be cited for its persuasive value under 

Fed. R. App. P. 32.1(a) and Tenth Cir. R. 32.1(A). 

FILED 

United States Court of Appeals 

Tenth Circuit 

February 21, 2018

Elisabeth A. Shumaker 

Clerk of Court
2 

period exists for these claims, the district court dismissed the suit based on 

timeliness. We affirm. 

I. Background 

Mr. Bryer grew up in Ponca City, Oklahoma, near ConocoPhillips’s 

refinery. For part of that time, Mr. Bryer also worked near the refinery. 

While living and working near the refinery, Mr. Bryer experienced 

symptoms—such as trouble breathing and a burning sensation in his eyes—

from emissions generated by the refinery. These symptoms led Mr. Bryer 

to move away from the refinery in 1975. 

Mr. Bryer was not alone, and many Ponca City citizens expressed 

concerns about the refinery. These concerns led a group of Ponca City 

residents to bring a class-action suit against ConocoPhillips, claiming that 

the refinery had emitted carcinogenic chemicals, including benzene. The 

suit focused on property damage, but the plaintiffs also alleged that the 

refinery’s emissions had caused or increased the risk of various diseases, 

including cancer. 

ConocoPhillips settled and paid members of the class in 1990. Mr. 

Bryer was one of the class members receiving a payment from the 

settlement. He knew at the time that the payment was to compensate for 

exposure to pollutants emitted by the refinery. 

Roughly sixteen years later (2006), a physician diagnosed Mr. Bryer 

with Acute Myeloid Leukemia, telling him that benzene exposure from his 
3 

residences and workplaces had “likely contributed to” his leukemia. 

Appellant’s App’x at 132. Mr. Bryer did not follow up with his doctors 

about the cause or source of his cancer. 

In 2015, Mr. Bryer met Ms. Samantha Hall, who had sued 

ConocoPhillips. Ms. Hall told Mr. Bryer that a connection existed between 

the refinery’s emissions and Acute Myeloid Leukemia. Later that year, Mr. 

Bryer sued ConocoPhillips, attributing his leukemia to the refinery’s 

emissions of benzene. 

II. Procedural History 

In district court, ConocoPhillips moved for summary judgment, 

arguing that the claim had accrued in 2006, which is when Mr. Bryer had 

been diagnosed with leukemia. Because a two-year period of limitations 

existed, ConocoPhillips argued that the suit was time-barred. Mr. Bryer 

argued that 

 his claim had not accrued until his meeting with Ms. Hall in 

2015 and 

 the doctrine of quasi-estoppel prevented ConocoPhillips from 

raising a timeliness defense. 

The district court granted summary judgment to ConocoPhillips, 

concluding that 

 the claim was untimely because Mr. Bryer should have known 

the underlying facts more than two years before he sued and 

 quasi-estoppel did not apply because ConocoPhillips had not 

advanced inconsistent positions. 
4 

Mr. Bryer appeals the grant of summary judgment. 

III. Standard of Review

We engage in de novo review, considering the evidence in the light 

most favorable to Mr. Bryer. Grynberg v. Total S.A., 538 F.3d 1336, 1346 

(10th Cir. 2008). We must uphold the grant of summary judgment if the 

evidence points only one way and is not susceptible to a reasonable 

inference that the suit is timely. Elm Ridge Expl. Co. v. Engle, 721 F.3d 

1199, 1216 (10th Cir. 2013). 

IV. Is the suit barred by the statute of limitations? 

As both parties acknowledge, we apply Oklahoma law on substantive 

aspects of our timeliness inquiry, including Oklahoma’s rules on tolling. 

Id. at 1210.1

 On procedural aspects of this inquiry, however, we apply 

federal law. Budinich v. Becton Dickinson & Co., 807 F.2d 155, 158 (10th 

Cir. 1986) (per curiam). 

The parties agree on the applicability of Oklahoma’s two-year period 

of limitations for all of Mr. Bryer’s claims. Okla. Stat. tit. 12, § 95(A)(3). 

The suit began in 2015. Therefore, the suit would ordinarily be considered 

timely only if the cause of action had accrued since 2013. Mr. Bryer argues 

 

1

 We strive to interpret Oklahoma law in the same manner that the 

Oklahoma Supreme Court would. Schrock v. Wyeth, Inc., 727 F.3d 1273, 

1280 (10th Cir. 2013). 
5 

that the cause of action accrued in 2015; ConocoPhillips argues that the 

cause of action accrued in 2006. 

A. The Discovery Rule 

The discovery rule tolls the statute of limitations until the plaintiff 

knows, or in the exercise of reasonable diligence should know, the facts 

underlying the cause of action. Watkins v. Cent. State Griffin Mem’l Hosp., 

377 P.3d 124, 132 (Okla. 2016). Under this standard, a plaintiff “is 

chargeable with knowledge of facts which he ought to have discovered in 

the exercise of reasonable diligence.” Daugherty v. Farmers Coop. Ass’n, 

689 P.2d 947, 951 (Okla. 1984). 

When the discovery rule applies, the statute of limitations is tolled 

until the plaintiff knows or should know of the injury and the cause of the 

injury. Woods v. Prestwick House, Inc., 247 P.3d 1183, 1189-90 (Okla. 

2011). Knowledge of the injury and its cause would often be sufficient. But 

here recognition of a cause of action would also require knowing the 

source of the benzene. We may assume, for the sake of argument, that 

uncertainty about the source of the emissions could toll the statute of 

limitations. Under this assumption, the discovery rule would have tolled 

the statute of limitations until Mr. Bryer knew or should have known of 

 his injury (that he had leukemia), 

 the cause of his injury (that the leukemia had been caused by 

benzene exposure), and 
6 

 the source of the benzene (that ConocoPhillips’s refinery had 

emitted the benzene causing the leukemia). 

 Both parties assume that the discovery rule applies. For the sake of 

argument, we too may draw the same assumption. 

B. Application of the Discovery Rule 

 As noted above, summary judgment to ConocoPhillips was 

appropriate if the undisputed evidence showed that Mr. Bryer should 

reasonably have known before 2013: (1) his injury, (2) the cause of the 

injury, and (3) the source of the benzene emissions. 

1. Injury

 It is undisputed that Mr. Bryer knew of his injury in 2006—nine 

years before he sued ConocoPhillips—when his doctors diagnosed him with 

leukemia. 

2. Cause

 It is also undisputed that Mr. Bryer knew the cause of his leukemia 

(benzene exposure) in 2006, when his doctor told him that exposure to 

benzene had “likely contributed to” his leukemia. Appellant’s App’x at 

132; see Schrock v. Wyeth, Inc., 727 F.3d 1273, 1280 (10th Cir. 2013) 

(stating that the plaintiff was aware of the cause of her symptoms when her 
7 

doctor told her that a certain chemical was “quite possib[ly]” responsible 

for her symptoms).2

3. Source

Mr. Bryer argues that he did not know the source of the benzene until 

2015, when he spoke with Ms. Hall. This argument creates two issues: 

1. When did Mr. Bryer know that the refinery emitted benzene? 

2. When did he know that the refinery’s benzene emissions were 

the likely cause of his leukemia? 

a. Knowledge of Benzene Emissions from the Refinery

Mr. Bryer should have known by 2006 that the refinery emitted 

benzene. Mr. Bryer argues in his reply brief that he could not have known 

that the Ponca City refinery’s emissions had included benzene. Mr. Bryer 

forfeited this argument by failing to raise it in his opening brief. Bronson 

v. Swensen, 500 F.3d 1099, 1104 (10th Cir. 2007).3

Mr. Bryer’s argument would fail even if we were to overlook the 

forfeiture. Mr. Bryer knew not only that the refinery had emitted a 

 

2

 Mr. Bryer contends that the limitations period does not begin to run 

until an expert expresses an opinion on causation. For the sake of 

argument, we assume that Mr. Bryer is right. But this assumption does not 

help him because an expert did express an opinion on causation in 2006 

when his physician attributed the leukemia to benzene exposure. 

3

 When an appellant omits an argument in the opening brief, we have 

sometimes referred to the omission as a forfeiture and sometimes as a 

waiver. Compare Bronson, 500 F.3d at 1104 (forfeiture), with Anderson v. 

U.S. Dep’t of Labor, 422 F.3d 1155, 1174 (10th Cir. 2005) (waiver). 
8 

significant volume of chemicals but also that these emissions had included 

benzene. For example, Mr. Bryer was aware that 

 other Ponca City residents had expressed concerns about the 

refinery’s emissions and their impact on health and the 

environment and 

 these concerns had led to a class-action complaint alleging 

harmful levels of benzene emissions from the refinery. 

Other sources of information were also available to Mr. Bryer before 2013. 

For example, multiple articles had noted the emission of benzene from the 

refinery. In addition, Mr. Bryer was a member of the class-action suit 

against ConocoPhillips, which alleged that the Ponca City refinery had 

emitted harmful levels of benzene that increased the class members’ risk of 

health problems. And the eventual settlement agreement acknowledged that 

all class members had been advised by their attorneys and a medical 

advisor that the ConocoPhillips refinery had caused, or may cause, cancer 

or an increased risk of cancer.4

 Though Mr. Bryer might not have read the 

settlement agreement, he knew when he received his settlement check that 

ConocoPhillips was settling because the refinery had polluted the air and 

groundwater. 

 Of course, these facts do not establish that the refinery’s benzene 

emissions were sufficiently concentrated to be harmful; indeed, that is the 

 

4

 Mr. Bryer asserts that he should not have been expected to remember 

the terms in a settlement agreement that he signed sixteen years earlier. 

But a reasonably diligent plaintiff could have obtained a settlement 

agreement that he or she had signed. 
9 

ultimate question on the merits. And Mr. Bryer’s knowledge of allegations

of high levels of benzene emissions did not provide him with certain 

knowledge of the refinery’s high emissions of benzene. But Mr. Bryer did 

not need “conclusive evidence.” Alexander v. Oklahoma, 382 F.3d 1206, 

1216 (10th Cir. 2004). Instead, he needed enough information to put him 

on notice that he had a cause of action against ConocoPhillips. Based on 

the available information, Mr. Bryer knew or should have known that the 

refinery’s emissions had included benzene. 

b. Knowledge of the Refinery as the Likely Source 

 For a cause of action, Mr. Bryer also needed to know that the 

refinery had been the likely source of the benzene. Maughan v. SW 

Servicing, Inc., 758 F.2d 1381, 1387 (10th Cir. 1985). Mr. Bryer should 

have been able to obtain this knowledge before 2013. 

 Mr. Bryer was diagnosed with leukemia in 2006 and told that the 

likely cause was benzene exposure from his residences and workplaces. In 

addition to this statement, Mr. Bryer had his own recollection of symptoms 

from the refinery’s emissions, knowledge that the refinery had emitted 

benzene, awareness of the public controversy surrounding the refinery’s 

emissions, and his own participation in a class-action suit alleging that 

ConocoPhillips’s benzene emissions had increased the risk of cancer. With 

such information, Mr. Bryer could reasonably have known before 2013 that 
10 

his leukemia had likely been caused by benzene emissions coming from 

ConocoPhillips’s refinery. 

 Mr. Bryer relies primarily on Maughan v. SW Servicing, Inc., 758 

F.2d 1381 (10th Cir. 1985). In Maughan, the court relaxed Utah’s 

discovery rule for cases involving suspected carcinogens because 

 such cases frequently involve “a mass of complex, 

controversial and rapidly changing scientific data” and 

 plaintiffs “may face enormous difficulties in determining when 

and where [they were] exposed to potential carcinogens.” 

758 F.2d at 1385-86. The court stated that when the suspected cause is a 

carcinogen, “the statute must be tolled until the plaintiff knows or should 

know of facts supporting the likelihood that one particular suspected 

carcinogen was the cause of his cancer, and has identified the likely source 

of his exposure to that carcinogen.” Id. at 1387 (emphasis added). Mr. 

Bryer does not dispute the first part of that test, for he acknowledges that 

benzene caused the leukemia. But he invokes the second part of the test, 

arguing that he could not have identified the refinery as the likely source 

of his exposure to benzene.5

 In Maughan, the court relied largely on scientific uncertainty about 

the cause of the cancer. There the plaintiffs attributed the cancer to 

 

5

 Mr. Bryer argues in his reply brief that the cancer might have 

originated from exposure to benzene at his other jobs. But Mr. Bryer 

forfeited this argument by waiting to raise it for the first time in his reply 

brief. See p. 7 & note 3, above. 
11 

radiation from the defendant’s uranium mill. But the doctors had told the 

plaintiffs that the cause of the cancer was “unknown,” and the link between 

low levels of radiation and cancer had not been scientifically established. 

Id. at 1386. 

 The Maughan court added that even if the link between radiation and 

cancer had been established, the plaintiffs lacked information tying their 

cancers to the defendant’s radiation: 

[T]he mere fact that there were public statements concerning 

the possible link between radiation and leukemia is not enough 

to establish, as a matter of law, that the plaintiffs should have 

known that emissions from the uranium processing plant in 

Monticello were the likely cause of the leukemia of their 

children and spouse. None of the articles cited by the 

defendants directly and unambiguously links the Monticello 

mill tailings with leukemia. Nor can it be said, as a matter of 

law, that the average layman would understand, after reading 

that fall-out from atomic bombs causes cancer, that the local 

uranium mill may have caused decedents’ leukemia. 

Id. at 1388. The court pointed to government studies, which had reassured 

the plaintiffs of (1) the absence of any connection between the mill and the 

cases of leukemia and (2) the existence of normal radiation levels at the 

mill. Id. at 1389. Mr. Bryer analogizes these reassurances to 

ConocoPhillips’s public statements about the absence of danger from the 

refinery’s emissions. 

 Based on Maughan, Mr. Bryer argues that even though the 

carcinogenic potential of benzene was well known, he lacked enough 
12 

information tying the refinery to his leukemia. Maughan’s language is 

broad, but there are two problems with Mr. Bryer’s argument: 

1. Unlike the plaintiffs in Maughan, Mr. Bryer had ample 

information identifying the refinery as a likely source of the 

benzene that caused his cancer. 

2. Mr. Bryer has not provided evidence of other plausible sources 

of exposure to sufficiently high concentrations of benzene. 

 First, there is far less scientific uncertainty here than in Maughan. In 

Maughan, the cause of the cancer was not known, so it was inherently 

difficult for the plaintiffs to attribute their cancer to the defendant’s mill. 

But Mr. Bryer was able to tie his injury to ConocoPhillips’s refinery. A 

physician told him not only that benzene had likely caused his cancer but 

also that the exposure had likely come from his residences and workplaces. 

This explanation pointed to the refinery because Mr. Bryer had lived and 

worked near the refinery when he experienced the symptoms from chemical 

emissions. And Mr. Bryer participated in a class-action suit against 

ConocoPhillips, which attributed cancer to benzene emissions from the 

Ponca City refinery. Together, the facts known and accessible to Mr. Bryer 

diminished the scientific uncertainty that the plaintiffs in Maughan had 

faced. See Grynberg v. Total S.A., 538 F.3d 1336, 1349-50 (10th Cir. 2008) 

(distinguishing Maughan because the plaintiff in Grynberg had not faced 

“similar scientific uncertainty or lack of expertise”). 
13 

 Second, Mr. Bryer has not supplied a plausible alternative to the 

refinery as the source of the benzene. For example, he does not give any 

details on whether his other jobs exposed him to benzene and, if so, how 

much. As a result, the refinery is the only plausible source based on the 

information in the summary-judgment record. See Plaza Speedway Inc. v. 

United States, 311 F.3d 1262, 1270-71 (10th Cir. 2002) (holding that the 

plaintiffs had sufficient information when they discovered contaminants in 

their well with “reason to suspect the source might have been the 

neighboring property” because they knew that various chemicals had been 

used on the neighboring property); accord Corcoran v. N.Y. Power Auth., 

202 F.3d 530, 543-44 (2d Cir. 1999) (holding that a claim accrued when 

the plaintiff knew that he “may have been exposed to radiation” at his 

workplace, that he had leukemia, and that a link existed between leukemia 

and radiation exposure). 

 In addition, Mr. Bryer does not identify any evidence of information 

learned since 2013 about the likelihood of the refinery as the source of his 

leukemia. Mr. Bryer states that in 2015, he overheard Ms. Samantha Hall 

note a connection between the refinery’s emissions and Acute Myeloid 

Leukemia. Mr. Bryer then contacted Ms. Hall to obtain additional 

information, leading him to file the complaint in this case. But Ms. Hall 

simply provided a contact with her law firm, alerting Mr. Bryer to the fact 

that others had also accused ConocoPhillips of causing their cancers. 
14 

 In essence, everything Mr. Bryer knows about his case now was 

accessible to him before 2013; there is nothing that Mr. Bryer alleges now 

that he could not have alleged before. Therefore, he could have brought his 

suit before 2013 and the suit is barred by the statute of limitations. See 

Samuel Roberts Noble Found. v. Vick, 840 P.2d 619, 625 (Okla. 1992) 

(“The operative date [for the discovery-rule inquiry] is that date on which 

plaintiff could have brought suit.”). 

* * * 

 In summary, Mr. Bryer knew or should have known before 2013 that 

 he had leukemia, 

 his leukemia had likely been caused by exposure to benzene, 

 his exposure to benzene likely came from his residences and 

workplaces, 

 he had lived and worked near the Ponca City refinery for much 

of his life, 

 he had experienced symptoms while living and working near 

the refinery, 

 the refinery had emitted benzene, and 

 ConocoPhillips had settled a lawsuit—in which Mr. Bryer was 

a class member and received a settlement payment—alleging 

that the refinery had emitted toxic levels of benzene that 

caused or increased the risk of cancer. 

Given these facts, Mr. Bryer was on notice before 2013 of the facts giving 

rise to his claim. Therefore, the 2015 suit is barred by Oklahoma’s twoyear statute of limitations. 
15 

V. Is ConocoPhillips’s statute-of-limitations defense barred by 

quasi-estoppel?

Mr. Bryer also argues that ConocoPhillips’s denial of culpability 

prevents assertion of the statute of limitations. We disagree. 

 Mr. Bryer invokes the doctrine of quasi-estoppel, which “appeals to 

the conscience of the court to prevent injustice by precluding a party from 

asserting a right inconsistent with a position previously taken by him.” 

Willard v. Ward, 875 P.2d 441, 443 (Okla. Civ. App. 1994). Mr. Bryer 

insists that ConocoPhillips is trying to assert a right (the statute-oflimitations defense) that is inconsistent with its previous position (its 

longstanding denial that the refinery caused cancer). According to Mr. 

Bryer, it is inconsistent for ConocoPhillips to deny that its refinery causes 

leukemia and then say that Mr. Bryer should have known years earlier that 

the refinery had caused his leukemia. 

 The Oklahoma Supreme Court recognizes three circumstances in 

which estoppel can be used to avoid a statute-of-limitations defense: 

1. The defendant has made “‘some assurance of settlement 

negotiations reasonably calculated to lull the plaintiff into a 

sense of security and delay action beyond the statutory 

period.’” 

2. The defendant has made “‘an express and repeated admission of 

liability in conjunction with promises of payment, settlement or 

performance.’” 

3. The defendant has engaged in “‘any false, fraudulent or 

misleading conduct or some affirmative act of concealment to 
16 

exclude suspicion and preclude inquiry, which induces one to 

refrain from timely bringing an action.’” 

Watkins v. Cent. State Griffin Mem’l Hosp., 377 P.3d 124, 131 & n.18 

(Okla. 2016) (quoting Jarvis v. City of Stillwater, 732 P.2d 470, 472-73 

(Okla. 1987)). 

Mr. Bryer cannot fit his facts into any of the three categories. To 

avoid this difficulty, Mr. Bryer urges another form of estoppel, quasiestoppel. But Oklahoma’s “[e]xceptions to statutes of limitations are 

strictly construed and are not enlarged on consideration of apparent 

hardship or inconvenience.” Calvert v. Swinford, 382 P.3d 1028, 1033 

(Okla. 2016). And the Oklahoma courts have never extended quasi-estoppel 

to a statute-of-limitations case. Therefore, we decline to recognize a new 

exception in Oklahoma to the statute of limitations. See Hogan v. Okla. 

Dep’t of Corr., 172 F.3d 878, at *2 (10th Cir. 1999) (unpublished) 

(“Absent affirmative indication that the State of Oklahoma recognizes 

equitable tolling in such a case, we decline to impute such a doctrine to the 

state.”). 

VI. Conclusion 

We conclude that 

 Mr. Bryer had sufficient information to bring his claim against 

ConocoPhillips more than two years before the filing of the 

complaint and 

 the doctrine of quasi-estoppel does not apply. 
17 

These conclusions render the complaint untimely, and we affirm the grant 

of summary judgment to ConocoPhillips. 

Entered for the Court 

Robert E. Bacharach 

Circuit Judge