                       United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
                                 ___________

                                 No. 96-3962
                                 ___________

United States of America,             *
                                      *
      Appellee,                       *   Appeals from the United States
                                      *   District Court for the District
      v.                              *   of South Dakota.
                                      *
Timothy J. Sinskey,                   *
                                      *
      Appellant.                      *


                                 ___________

                                 No. 96-3965
                                 ___________

United States of America,             *
                                      *
      Appellee,                       *
                                      *
      v.                              *
                                      *
Wayne Kumm,                           *
                                      *
      Appellant.                      *
                                    ___________

                              Submitted: May 20, 1997

                                   Filed: July 11, 1997
                                    ___________

Before RICHARD S. ARNOLD, Chief Judge, and BOWMAN and MORRIS
      SHEPPARD ARNOLD, Circuit Judges.
                           ___________

MORRIS SHEPPARD ARNOLD, Circuit Judge.

      The defendants appeal their convictions for criminal violations of the Clean
Water Act. We affirm the judgments of the trial court.1

                                               I.
       In the early 1990s, Timothy Sinskey and Wayne Kumm were, respectively, the
plant manager and plant engineer at John Morrell & Co. ("Morrell"), a large
meat-packing plant in Sioux Falls, South Dakota. The meat-packing process created
a large amount of wastewater, some of which Morrell piped to a municipal treatment
plant and the rest of which it treated at its own wastewater treatment plant ("WWTP").
After treating wastewater at the WWTP, Morrell would discharge it into the Big Sioux
River.

       One of the WWTP's functions was to reduce the amount of ammonia nitrogen
in the wastewater discharged into the river, and the Environmental Protection Agency
("EPA") required Morrell to limit that amount to levels specified in a permit issued
under the Clean Water Act ("CWA"), see 33 U.S.C. §§ 1251-1387. As well as


      1
       The Honorable Lawrence L. Piersol, United States District Judge for the District
of South Dakota.

                                          -2-
specifying the acceptable levels of ammonia nitrogen, the permit also required Morrell
to perform weekly a series of tests to monitor the amounts of ammonia nitrogen in the
discharged water and to file monthly with the EPA a set of reports concerning those
results.

       In the spring of 1991, Morrell doubled the number of hogs that it slaughtered and
processed at the Sioux Falls plant. The resulting increase in wastewater caused the
level of ammonia nitrate in the discharged water to be above that allowed by the CWA
permit. Ron Greenwood and Barry Milbauer, the manager and assistant manager,
respectively, of the WWTP, manipulated the testing process in two ways so that
Morrell would appear not to violate its permit. In the first technique, which the parties
frequently refer to as "flow manipulation" or the "flow game," Morrell would discharge
extremely low levels of water (and thus low levels of ammonia nitrogen) early in the
week, when Greenwood and Milbauer would perform the required tests. After the tests
had been performed, Morrell would discharge an exceedingly high level of water (and
high levels of ammonia nitrogen) later in the week. The tests would therefore not
accurately reflect the overall levels of ammonia nitrogen in the discharged water. In
addition to manipulating the flow, Greenwood and Milbauer also engaged in what the
parties call "selective sampling," that is, they performed more than the number of tests
required by the EPA but reported only the tests showing acceptable levels of ammonia
nitrogen. When manipulating the flow and selective sampling failed to yield the
required number of tests showing acceptable levels of ammonia nitrogen, the two
simply falsified the test results and the monthly EPA reports, which Sinskey then signed
and sent to the EPA. Morrell submitted false reports for every month but one from
August, 1991, to December, 1992.
       As a result of their participation in these activities, Sinskey and Kumm were
charged with a variety of CWA violations. After a three-week trial, a jury found
Sinskey guilty of eleven of the thirty counts with which he was charged, and Kumm
guilty of one of the seventeen counts with which he was charged. In particular, the jury


                                          -3-
found both Sinskey and Kumm guilty of knowingly rendering inaccurate a monitoring
method required to be maintained under the CWA, in violation of 33 U.S.C.
§ 1319(c)(4), and Sinskey guilty of knowingly discharging a pollutant into waters of the
United States in amounts exceeding CWA permit limitations, in violation of 33 U.S.C.
§ 1319(c)(2)(A); see also 33 U.S.C. § 1311(a). Each appeals his conviction.

                                              II.
        Sinskey first challenges the jury instructions that the trial court gave with respect
to 33 U.S.C. § 1319(c)(2)(A), which, among other things, punishes anyone who
"knowingly violates" § 1311 or a condition or limitation contained in a permit that
implements § 1311. That section of the CWA prohibits the discharge of pollutants
except in compliance with, among other provisions, § 1342, which establishes the
National Pollutant Discharge Elimination System ("NPDES"). The NPDES authorizes
the EPA to issue permits that allow the discharge of certain pollutants within specified
limitations and with specified reporting and monitoring conditions. As applied in this
case, § 1319(c)(2)(A) therefore prohibits the discharge of pollutants in amounts
exceeding the limitations specified in an NPDES permit.

       The trial court gave an instruction, which it incorporated into several substantive
charges, that in order for the jury to find Sinskey guilty of acting "knowingly," the proof
had to show that he was "aware of the nature of his acts, perform[ed] them
intentionally, and [did] not act or fail to act through ignorance, mistake, or accident."
The instructions also told the jury that the government was not required to prove that
Sinskey knew that his acts violated the CWA or permits issued under that act. Sinskey
contests these instructions as applied to 33 U.S.C. § 1319(c)(2)(A), arguing that
because the adverb "knowingly" immediately precedes the verb "violates," the
government must prove that he knew that his conduct violated either the CWA or the
NPDES permit. We disagree.




                                            -4-
        Although our court has not yet decided whether 33 U.S.C. § 1319(c)(2)(A)
requires the government to prove that a defendant knew that he or she was violating
either the CWA or the relevant NPDES permit when he or she acted, we are guided in
answering this question by the generally accepted construction of the word "knowingly"
in criminal statutes, by the CWA's legislative history, and by the decisions of the other
courts of appeals that have addressed this issue. In construing other statutes with
similar language and structure, that is, statutes in which one provision punishes the
"knowing violation" of another provision that defines the illegal conduct, we have
repeatedly held that the word "knowingly" modifies the acts constituting the underlying
conduct. See United States v. Farrell, 69 F.3d 891, 893 (8th Cir. 1995), cert. denied,
116 S. Ct. 1283 (1996), and United States v. Hern, 926 F.2d 764, 766-68 (8th Cir.
1991).

       In Farrell, 69 F.3d at 892-93, for example, we discussed 18 U.S.C. § 924(a)(2),
which penalizes anyone who "knowingly violates" § 922(o)(1), which in turn prohibits
the transfer or possession of a machine gun. In construing the word "knowingly," we
held that it applied only to the conduct proscribed in § 922(o)(1), that is, the act of
transferring or possessing a machine gun, and not to the illegal nature of those actions.
A conviction under § 924(a)(2) therefore did not require proof that the defendant knew
that his actions violated the law.
       We see no reason to depart from that commonly accepted construction in this
case, and we therefore believe that in 33 U.S.C. § 1319(c)(2)(A), the word "knowingly"
applies to the underlying conduct prohibited by the statute. Untangling the statutory
provisions discussed above in order to define precisely the relevant underlying conduct,
however, is not a little difficult. At first glance, the conduct in question might appear
to be violating a permit limitation, which would imply that § 1319(c)(2)(A) requires
proof that the defendant knew of the permit limitation and knew that he or she was
violating it. To violate a permit limitation, however, one must engage in the conduct
prohibited by that limitation. The permit is, in essence, another layer of regulation in


                                          -5-
the nature of a law, in this case, a law that applies only to Morrell. We therefore
believe that the underlying conduct of which Sinskey must have had knowledge is the
conduct that is prohibited by the permit, for example, that Morrell's discharges of
ammonia nitrates were higher than one part per million in the summer of 1992. Given
this interpretation of the statute, the government was not required to prove that Sinskey
knew that his acts violated either the CWA or the NPDES permit, but merely that he
was aware of the conduct that resulted in the permit's violation.

       This interpretation comports not only with our legal system's general recognition
that ignorance of the law is no excuse, see Cheek v. United States, 498 U.S. 192, 199
(1991), but also with Supreme Court interpretations of statutes containing similar
language and structure. In United States v. International Minerals & Chemical Corp.,
402 U.S. 558 (1971), for example, the Court analyzed a statute that punished anyone
who "knowingly violate[d]" certain regulations pertaining to the interstate shipment of
hazardous materials. In holding that a conviction under the statute at issue did not
require knowledge of the pertinent law, the Court reasoned that the statute's language
was merely a shorthand designation for punishing anyone who knowingly committed
the specific acts or omissions contemplated by the regulations at issue, and that the
statute therefore required knowledge of the material facts but not the relevant law. Id.
at 562-63. The Court also focused on the nature of the regulatory scheme at issue,
noting that where "dangerous or ... obnoxious waste materials" are involved, anyone
dealing with such materials "must be presumed" to be aware of the existence of the
regulations. Id. at 565. Requiring knowledge only of the underlying actions, and not
of the law, would therefore raise no substantial due process concerns. Id. at 564-65.
Such reasoning applies with equal force, we believe, to the CWA, which regulates the
discharge into the public's water of such "obnoxious waste materials" as the byproducts
of slaughtered animals.

       The act's legislative history, moreover, supports our view of the mens rea
required for conviction under 33 U.S.C. § 1319(c)(2)(A). In 1987, Congress amended

                                          -6-
the act, in part to increase deterrence by strengthening the criminal sanctions for its
violation. See, e.g., H.R. Conf. Rep. No. 99-1004 at 138 (1986) and S. Rep. No. 99-50
at 29-30 (1985). To that end, Congress changed the term "willfully" to "knowingly"
in that section of the act dealing with intentional violations. See 133 Cong. Rec. H131
(daily ed. Jan. 7, 1987) (statement of Rep. J. Howard), reprinted in 1987 U.S.C.C.A.N.
5, 28, and 33 U.S.C. § 1319, historical and statutory notes, 1987 amendment, at 197
(West supp. 1997). Although Congress did not explicitly discuss this change, it may
logically be viewed as an effort to reduce the mens rea necessary for a conviction, as
the word "willfully" generally connotes acting with the knowledge that one's conduct
violates the law, while the word "knowingly" normally means acting with an awareness
of one's actions. Compare Cheek, 498 U.S. at 201, with International Minerals, 402
U.S. at 562-63. See also Babbitt v. Sweet Home Chapter of Communities, 115 S. Ct.
2407, 2412 n.9 (1995) (discussing change in Endangered Species Act from "willfully"
to "knowingly"), and Hern, 926 F.2d at 767.

       Our confidence in this interpretation is increased by decisions of the only other
appellate courts to analyze the precise issue presented here. See United States v.
Hopkins, 53 F.3d 533, 541 (2d Cir. 1995), cert. denied, 116 S. Ct. 773 (1996), and
United States v. Weitzenhoff, 35 F.3d 1275, 1283-86 (9th Cir. 1993), cert. denied,
115 S. Ct. 939 (1995). Both cases held that 33 U.S.C. § 1319(c)(2)(A) does not
require proof that the defendant knew that his or her acts violated the CWA or the
NPDES permits at issue.
       Contrary to the defendants' assertions, moreover, United States v. Ahmad,
101 F.3d 386 (5th Cir. 1996), is inapposite. In Ahmad, 101 F.3d at 388, a convenience
store owner pumped out an underground gasoline storage tank into which some water
had leaked, discharging gasoline into city sewer systems and nearby creeks in violation
of 33 U.S.C. § 1319(c)(2)(A). At trial, the defendant asserted that he thought that he
was discharging water, and that the statute's requirement that he act knowingly required
that the government prove not only that he knew that he was discharging something,


                                          -7-
but also that he knew that he was discharging gasoline. Id. at 390. The Fifth Circuit
agreed, holding that a defendant does not violate the statute unless he or she acts
knowingly with regard to each element of an offense. Id. at 391. Ahmad, however,
involved a classic mistake-of-fact defense, and is not applicable to a mistake-of-law
defense such as that asserted by Sinskey and Kumm. Indeed, the Fifth Circuit noted
as much, distinguishing Hopkins, 53 F.3d at 533, and Weitzenhoff, 35 F.3d at 1275,
on the grounds that those decisions involved a mistake-of-law defense. See Ahmad,
101 F.3d at 390-91.

        Sinskey, joined by Kumm, also challenges the trial court's instructions with
respect to 33 U.S.C. § 1319(c)(4), arguing that the government should have been
required to prove that they knew that their acts were illegal. This argument has even
less force with respect to § 1319(c)(4) -- which penalizes a person who "knowingly
falsifies, tampers with, or renders inaccurate any monitoring device or method required
to be maintained" by the CWA -- than it does with respect to § 1319(c)(2)(A). In
§ 1319(c)(4), the adverb "knowingly" precedes and explicitly modifies the verbs that
describe the activities that violate the act.

      We have repeatedly held that, in other statutes with similar language, the word
"knowingly" refers only to knowledge of the relevant activities (in this case, the
defendants' knowledge that they were rendering the monitoring methods inaccurate by
aiding and abetting in the flow games and selective sampling). See, e.g., United
States v. Hopkins, 53 F.3d at 541; United States v. Enochs, 857 F.2d 491, 492-94 (8th
Cir. 1988), cert. denied, 490 U.S. 1022 (1989); and United States v. Udofot, 711 F.2d
831, 837 (8th Cir. 1983), cert. denied, 464 U.S. 896 (1983). Based on this well
established constructional convention, and the equally well known principle that a term
that appears in a statute more than once should ordinarily be construed the same way
each time, Ratzlaf v. United States, 510 U.S. 135, 143 (1994), we see no reason to read
a requirement that a defendant know of the illegal nature of his or her acts into 33
U.S.C. § 1319(c)(4). Contrary to the defendants' assertions, moreover, requiring the

                                          -8-
government to prove only that the defendant acted with awareness of his or her conduct
does not render § 1319(c)(4) a strict liability offense.

       Sinskey also contends that the trial court abused its discretion by admitting into
evidence Milbauer's "secret logs" -- that is, notes that Milbauer took in which he
recorded the actual levels of ammonia nitrogen being discharged -- because the logs
constituted expert scientific evidence that did not meet the threshold standards of
accuracy and reliability. See Fed. R. Evid. 702 and Daubert v. Merrell Dow Pharm.,
Inc., 509 U.S. 579, 594 (1993). Sinskey appears not to contest the fact that, in the
abstract, the means of testing ammonia nitrogen levels that Milbauer used, an ammonia
nitrate probe, was sufficiently accurate and reliable. Sinskey instead attacks the
manner in which Milbauer used the probe, arguing that certain deviations by Milbauer
from the standard protocol prescribed for using the probe rendered his results so
unreliable as to negate, in this case, the probe's generally accepted accuracy and
reliability. See, e.g., United States v. Johnson, 56 F.3d 947, 952-53 (8th Cir. 1995),
and United States v. Martinez, 3 F.3d 1191, 1198 (8th Cir. 1993), cert. denied,
510 U.S. 1062 (1994).

       After a careful review of the trial court's two-day hearing on this issue and the
relevant testimony at trial, we find no error. Although Sinskey identified several
practices of Milbauer that deviated from the standard protocol for use of the probe, the
government produced testimony tending to show that these deviations did not affect
the reliability of Milbauer's test results. Therefore, admitting the secret logs and
allowing the jury to consider these deviations when deciding what weight to give the
logs was, we believe, well within the trial court's discretion.
       We similarly find no error in the trial court's decision not to grant Sinskey's
motion seeking to limit severely the government's ability to cross-examine an
unindicted co-conspirator. Although a trial court must strike a balance between a
witness's fifth amendment privilege and the defendant's sixth amendment right to cross-


                                          -9-
examination, see, e.g., United States v. Rubin, 836 F.2d 1096, 1099-1100 (8th Cir.
1988), there is no indication in the present case that the trial court failed properly to
strike such a balance. Although the trial court refused to grant the requested motion,
it indicated that it would be willing to consider other restrictions on the cross-
examination's scope. After the defense suggested none, the trial court ruled that it
would allow the witness, after direct examination, to invoke his fifth amendment
privilege outside the presence of the jury. We believe that this ruling gave Sinskey
everything that he requested, and more. The trial court therefore did not err in
balancing the defendant's and the witness's rights in the manner that it chose.

                                            III.
       Kumm attacks his conviction for violating 33 U.S.C. § 1319(c)(4) on a number
of grounds, first among them the sufficiency of the government's evidence. Kumm
claims that the government's evidence established only that he failed to stop others from
rendering inaccurate Morrell's monitoring methods, not that he affirmatively
participated in the deceit either directly or by aiding and abetting those who did. As
Kumm correctly argues, to convict him of aiding and abetting the monitoring scheme,
the government must prove more than his mere association with, and knowledge of the
activities of, Greenwood, Milbauer, and Sinskey. United States v. Nunn, 940 F.2d
1128, 1131 (8th Cir. 1991). Instead, the government must show that Kumm associated
himself with the misleading monitoring scheme, participated in it "as something [he]
wished to bring about," and acted in such a way as to ensure its success. United States
v. Hernandez, 986 F.2d 234, 238 (8th Cir. 1993), quoting United States v. Posters 'N'
Things, Ltd., 969 F.2d 652, 661 (8th Cir. 1992), aff'd, 511 U.S. 513 (1994).
Encouraging the perpetrators of a crime in their efforts to effect that crime is therefore
aiding and abetting the commission of a crime. See Hernandez, 986 F.2d at 238, and
Nunn, 940 F.2d at 1131.

       After a careful review of the record in the light most favorable to the jury's
verdict, see United States v. Baker, 98 F.3d 330, 338 (8th Cir. 1996), cert. denied, 117

                                          -10-
S. Ct. 1456 (1997), we believe that the evidence against Kumm, although hardly
overwhelming, is not so weak that no reasonable juror could have convicted him. See
id. In particular, we believe that the evidence supports a verdict that he aided and
abetted the misleading monitoring scheme by encouraging Greenwood to render
Morrell's monitoring methods inaccurate and by discouraging him from complaining
about it to others at the WWTP.

       Kumm once reassured a worried Greenwood, for example, "not to worry about
[the violations] because if we did get caught, Morrell's had enough lawyers and
lobbyists that it wouldn't be a problem." Although Kumm knew of Greenwood's illegal
activities, moreover, he praised Greenwood on employee evaluations and even
recommended that Greenwood receive a raise. When Greenwood began complaining
about the violations and campaigning for physical improvements at the WWTP to
decrease future violations, Kumm silenced him. At a meeting of the plant's mechanical
department, for example, Kumm told Greenwood that "[n]ow is not the time or the
place to discuss those matters" when Greenwood raised the subject of the violations.
 Lastly, although Greenwood would "rant and rave" to Kumm several times a week
about the permit violations and about getting the WWTP fixed, Kumm responded only
by submitting to Morrell headquarters routine requests for future improvements that
were similar to previous requests that had already been denied. We believe that these
affirmative acts constitute sufficient evidence to support Kumm's conviction.

       Kumm challenges the jury instructions on several grounds. In addition to the
issue discussed above, Kumm asserts that the essence of the government's case was his
failure to report the violations and to intervene to stop their continuation, that he had
no such duties, and that the trial court therefore abused its discretion when it refused
to give an instruction to the jury that Kumm had no affirmative legal duty to report
violations of the CWA permits or to intervene to prevent them. Though such an
instruction would certainly have been appropriate, after a careful review of the record


                                          -11-
we see no abuse of discretion in the trial court's decision not to give the requested
instruction, for the following reasons.

       Contrary to Kumm's assertions, the government's case did not focus solely on
Kumm's role as a supervisor and his failure to report the violations or to intervene. We
note at the outset of this discussion that Kumm was neither charged with, nor convicted
of, a failure to report CWA permit violations. Instead, he was charged with, and
convicted of, "render[ing] inaccurate" the monitoring methods required under Morrell's
CWA permit. See 33 U.S.C. § 1319(c)(4). Kumm argues, however, that the testimony
of several witnesses and certain portions of the government's closing argument so
emphasized his supervisory status and his inaction, that they led the jury to convict him
for being an innocent bystander who merely failed to report the violations or to
intervene. After a careful review of the statements at issue, in their full context, we
disagree.

       As we indicated above, the government sufficiently proved that Kumm actively
encouraged the flow manipulation and selective sampling, thereby affirmatively
participating in the misleading monitoring scheme. Presenting evidence that Kumm
was a supervisor, that is, that he was in a position capable of giving rewards and
reassurances, was but a necessary part of showing how he was able to encourage
Greenwood. Likewise, testimony that Kumm neither reported nor interfered with the
permit violations was consistent with the government's claim that Kumm was
encouraging illegal activity. Contrary to Kumm's assertions, this evidence did not
merely tend to show that Kumm violated some supposed duty to report permit
violations; it tended instead to prove acts of concealment on Kumm's part that allowed
the selective sampling scheme effectively to camouflage Morrell's violations.

       Nor do we find reversible error in the prosecutor's closing argument. As Kumm
points out, the prosecutor did, at times, argue that Sinskey and Kumm had "a duty" or
"an obligation" to "protect the river" or "make sure that the plant operated in

                                          -12-
compliance with the law." In the context of the full closing argument, however, we
believe that these statements refer not to legal duties, but rather to the duties of his job.
And while the prosecutor did refer to what Kumm did not do, such as not reporting the
violations and not interfering with them, these references were always, as a rhetorical
device, juxtaposed against what Kumm did do. In context, we do not believe that
these statements suggested to the jury that it could convict Kumm solely for the failure
to report permit violations or the failure to intervene to stop them.

       We do, however, believe that the prosecutor misstated the law when he told the
jury, with respect to the violation of 33 U.S.C. § 1319(c)(4), that if "these two
gentlemen knew that the selective sampling and the flow game was going on, they are
guilty." We note, though, not only that this statement was not objected to either during
or after the argument in question, but also that we believe that the jury instructions
sufficiently cured whatever unfair prejudice this statement may have created. The trial
court told the jury that it had to "follow the law as stated in these instructions," that it
had to "follow my instructions on the law, even if you thought the law was different,"
and that "[i]t would be a violation of your sworn duty to base your verdict upon any
rules of law other than the ones given you in these instructions." The instructions
relevant to § 1319(c)(4) defined accurately the elements of a violation of it and the
elements of aiding and abetting, including the necessity that a defendant act knowingly.
The aiding and abetting instructions, moreover, correctly told the jury that a defendant's
mere presence at a crime scene or his mere association with the perpetrators of a
violation was insufficient to prove that the defendant aided and abetted the commission
of an offense.

                                         IV.
       For the foregoing reasons, we affirm the convictions in all respects.




                                            -13-
A true copy.

      Attest:

         CLERK, U.S. COURT OF APPEALS, EIGHTH CIRCUIT.




                          -14-
