In the present action, Mr. Richards filed a motion to modify his sentence pursuant to 18 U.S.C. § 3582(c)(2). In so doing, he relies upon amended commentary to the sentencing guidelines which excludes waste water from the definition of “mixture or substance” for purposes of weighing methamphetamine. The district court granted the motion and reduced Mr. Richards’ sentence from 188 months to 60 months. On appeal, the government concedes that the commentary changed the applicable guideline range but asserts that the commentary cannot alter the definition of “mixture or substance” for purposes of the statutory minimum sentence. The government thus contends that Mr. Richards’ sentence remains subject to a statutory mandatory minimum of 120 months. We affirm.
I.
In 1989, Mr. Richards pled guilty to possession with intent to manufacture methamphetamine, in violation of 21 U.S.C. § 841(a)(1). The statutory penalty provision and the relevant sentencing guideline provide two possible methods for measuring methamphetamine for sentencing purposes: the weight of the pure drug or the weight of the “mixture or substance” containing a detectable amount of the drug. See 21 U.S.C. § 841(b)(1);1 U.S.S.G. § 2D1.1.2 Mr. Richards possessed 28 grams of pure methamphetamine, which was combined with waste water to form a mixture weighing 32 kilograms. Ree., vol. IV at 14. Consequently, the court sentenced him to 188 months of imprisonment and five years of supervised release.3
*1533Mr. Richards challenged that sentence on three separate occasions. First, he filed a motion to vacate the sentence pursuant to 28 U.S.C. § 2255, which the district court denied. Then he filed a second motion under section 2255. The district court granted this motion, but we reversed on appeal, holding that the second petition constituted an abuse of the writ. United States v. Richards, 5 F.3d 1369 (10th Cir.1993). His latest avenue of attack is 18 U.S.C. § 3582(e)(2), which allows a district court to modify the prison term of a defendant “who has been sentenced to a term of imprisonment based on a sentencing range that has subsequently been lowered by the Sentencing Commission....”
In the current motion, Mr. Richards alleged and the district court agreed that the amended commentary to section 2D1.1 of the sentencing guidelines mandates that his sentence be reduced from 188 months to 60 months. The commentary now provides that “[m]ixture or substance does not include materials that must be separated from the controlled substance before the controlled substance can be used.” U.S.S.G. § 2D1.1, comment. n. 1. The amended commentary became effective on November 1, 1993, and the Sentencing Commission expressly made it retroactive. U.S.S.G. § 1B1.10(c). The commentary lists “waste water from an illicit laboratory” as an example of a substance that cannot comprise a “mixture or substance.” U.S.S.G. § 2D1.1, comment, n. 1.
The government concedes that this amended commentary is applicable to Mr. Richards. It does not contest his assertion that, under the guidelines, his sentence must be based on the amount of pure methamphetamine and that his sentencing level must therefore be reduced from a level 38 to an 18. The government asserts, however, that the Sentencing Commission’s decision to exclude waste water from “mixture or substance” does not alter the definition of that phrase in the statutory context. Claiming that we have construed section 841(b) to include waste water as part of a “mixture or substance,” the government maintains that Mr. Richards remains subject to a statutory mandatory minimum term of imprisonment of ten years, which- trumps the guideline sentence.
We review de novo the district court’s interpretation of statutory provisions and the sentencing guidelines. See United States v. Agbai, 930 F.2d 1447, 1448 (10th Cir.1991).
II.
The government bases its argument on the notion that amended commentary to the sentencing guidelines cannot change the established judicial interpretation of a statute. Although we agree with this assertion, it is irrelevant to our inquiry because we disagree that we have definitively construed the statute itself to include waste water in its definition of “mixture or substance.” The amended commentary may therefore instruct our interpretation of the statute.
The government asserts that the Sentencing Commission does not have authority to supersede our precedent interpreting “mixture or substance” for purposes of section 841(b). See United States v. Neal, 46 F.3d 1405, 1409 (7th Cir.1995) (en bane), cert. granted, — U.S. - -, 115 S.Ct. 2576, 132 L.Ed.2d 826 (1995) (“The Commission is without authority to override [Supreme Court precedent].”); United States v. Palacio, 4 F.3d 150, 154 (2d Cir.1993) (“[OJnee we have construed [a] statute, we will not reinterpret it in the absence of new guidance from Congress.”), cert. denied, — U.S. -, 114 S.Ct. 1194,127 L.Ed.2d 543 (1994). This argument rests on the assumption that we have precedent authoritatively construing section 841(b).
In Neal, the Seventh Circuit held that an amended sentencing guideline prescribing a presumptive per dose weight of LSD4 did *1534not alter the interpretation of section 841(b) established in Chapman v. United States, 500 U.S. 453, 111 S.Ct. 1919, 114 L.Ed.2d 524 (1991). Neal, 46 F.3d at 1408-09. Chapman construed section 841(b) to include the weight of blotter paper containing “hits” of pure LSD in the measurement of a “mixture or substance.” 500 U.S. at 461, 111 S.Ct. at 1925. Citing Chapman, the Sentencing Commission itself recognized that its new approach to measuring LSD for guideline purposes “does not override the applicability of ‘mixture or substance’ for the purpose of applying any mandatory minimum sentence.” U.S.S.G. § 2D1.1 backg’d; see also United States v. Boot, 25 F.3d 52, 55 (1st Cir.1994) (“[W]e conclude that Congress simply acquiesced in the restrictive reach of Amendment 488 duly noted by the Commission in application note 18.”).
Likewise, the Second Circuit in Palacio held that the sentencing guidelines’ amended definition of “cocaine base” did not alter its conflicting statutory interpretation of the same term established in United States v. Jackson, 968 F.2d 158 (2d Cir.), cert. denied, - U.S. -, 113 S.Ct. 664, 121 L.Ed.2d 589 (1992). See Palacio, 4 F.3d at 154-55. Recognizing that the amended commentary would be authoritative in determining base offense levels under the guidelines, the court noted that its own interpretation of the statute in Jackson was binding for purposes of determining the mandatory minimum where “our initial construction of [the] statute [was] solely the result of an independent judicial interpretation of a statutory term.” Id. at 154.
We agree that amended commentary to the sentencing guidelines cannot alter any prior, independent construction of section 841(b) we may have made. However, we have never specifically interpreted the statute apart from the guideline to require the inclusion of waste water in its definition of “mixture or substance.”
The government concedes that we have interpreted “mixture or substance” only in the context of section 2D1.1 of the sentencing guidelines. Aplt.Br. at 16; see United States v. Killion, 7 F.3d 927 (10th Cir.1993) (weight of waste by-products may be used to calculate base offense level under section 2D1.1), cert. denied, — U.S.-, 114 S.Ct. 1106, 127 L.Ed.2d 418 (1994); United States v. Dorrough, 927 F.2d 498, 502 (10th Cir.1991) (same); United States v. Callihan, 915 F.2d 1462 (10th Cir.1990) (same). It argues, however, that because “ ‘[m]ixture or substance’ as used in [section 2D1.1] has the same meaning as in 21 U.S.C. § 841,” U.S.S.G. § 2D1.1 comment, n. 1, we have implicitly settled the statutory issue as well. We are not persuaded.
In Callihan and Dorrough, we construed “mixture or substance” in section 2D1.1 of the guidelines without any reference or citation to the statute or its construction, merely relying on the Sentencing Commission’s admonition that “if any mixture or compound contains any detectable amount of a controlled substance, the entire amount of the mixture or compound shall be considered in measuring the quantity.” Callihan, 915 F.2d at 1463 (quoting U.S.S.G. § 2D1.1, table n. * (Oct. 1987)); see also Dorrough, 927 F.2d at 502 (relying on Callihan).
We later were faced with determining whether the United States Supreme Court decision, Chapman v. United States, 500 U.S. 453, 111 S.Ct. 1919, 114 L.Ed.2d 524 (1991), supersedes the Tenth Circuit’s earlier position that the weight óf waste products that are the by-product of a drug manufacturing process but that contain a detectable amount of a controlled substance may be used in calculating a defendant’s base offense level under § 2D1.1 of the guidelines. The district court, citing United States v. Dorrough, 927 F.2d 498, 502 (10th Cir.1991), and United States v. Callihan, 915 F.2d 1462, 1463 (10th Cir.1990), ruled that the weight of unusable waste by-products containing a detectable amount of P-2-P are to be included for sentencing purposes under the Guidelines. Killion, 788 F.Supp. at 1167. Killion, however, maintains that the district court erred in including the weight of waste byproducts in calculating his sentence because Dorrough and Callihan were decided prior to and were effectively overruled by Chapman.
Killion, 7 F.3d at 929. We held that the Supreme Court’s recent interpretation of section 841 in Chapman did not overrule Colli-*1535han and Dorrough. Id. at 934. Noting a split among the circuits, we acknowledged the majority of those courts had held that Chapman and its emphasis on the marketability of the blotter paper mandated that “sentencing calculations under § 2D1.1 may not be based on the weight of mixtures containing unusable, unmarketable materials.”5 Id. at 932 (citing United States v. Acosta, 963 F.2d 551 (2d Cir.1992); United States v. Rodriguez, 975 F.2d 999 (3d Cir.1992); United States v. Jennings, 945 F.2d 129 (6th Cir.1991); United States v. Johnson, 999 F.2d 1192 (7th Cir.1993); United States v. Robins, 967 F.2d 1387 (9th Cir.1992); United States v. Rolande-Gabriel, 938 F.2d 1231 (11th Cir.1991)). Recognizing, however, that we were “bound by the precedent of prior panels absent en banc reconsideration or a superceding contrary decision by the Supreme Court,” id. at 930, we joined the First and Fifth Circuits in “expressly declining to overrule precedent” to the contrary where Chapman “ ‘did not speak’ ” to the issue. Id. at 933 (quoting United States v. Walker, 960 F.2d 409, 412 (5th Cir.), cert. denied, — U.S. -, 113 S.Ct. 443, 121 L.Ed.2d 362 (1992)). We held that the narrow holding in Chapman regarding the weight of an LSD carrier medium did not affect our “clear precedent” construing section 2D1.1 to include waste by-products. Id. at 934. Rather than interpret the statute, Killion merely rejected the notion that the Supreme Court’s interpretation of the statute in a different context required us to change our prior construction of the guideline. Moreover, Killion expressly stated that “[i]t is the Guideline we are construing.” Id. at 935. We believe a fair reading of Killion is that it was construing section 2D1.1 as required by prior Tenth Circuit cases, not making a definitive judicial interpretation of 21 U.S.C. § 841(B). Thus, we have not independently and authoritatively construed the term “mixture or substance” for purposes of section 841; we merely followed the Sentencing Commission’s prior interpretation via its guideline.
Because we have not ourselves separately interpreted “mixture or substance” for statutory purposes, we are now faced with this task. “Our job in construing statutes is to effectuate the intent reflected in the language of the enactment and the legislative process....” State of Colorado v. Idarado Mining Co., 916 F.2d 1486, 1494 (10th Cir.1990). Although a combination of methamphetamine and waste water seems to fit within a dictionary definition of “mixture,” we are not required to “‘produce a result demonstrably at odds with the intentions of its drafters.’ ”6 United States v. Ron Pair Enter., Inc., 489 U.S. 235, 242, 109 S.Ct. 1026, 1031, 103 L.Ed.2d 290 (1989) (quoting Griffin v. Oceanic Contractors, Inc., 458 U.S. 564, 571, 102 S.Ct. 3245, 3250, 73 L.Ed.2d 973 (1982)); see also NLRB v. Lion Oil Co., 352 U.S. 282, 288, 77 S.Ct. 330, 333-34, 1 L.Ed.2d 331 (1957). The Court said in Lion Oil Co.:
If the above words are read in complete isolation from their context in the Act, such an interpretation is possible. However, “In expounding a statute, we must not be guided by a single sentence or member of a sentence, but look to the provisions of the whole law, and to its object and policy.” Moreover, in Mastro Plastics we cautioned against accepting a construction that “would produce incongruous results.”
Id. at 288, 77 S.Ct. at 334 (quoting Mastro Plastics Corp. v. NLRB, 350 U.S. 270, 285, 286, 76 S.Ct. 349, 359, 359-60, 100 L.Ed. 309 (1956) (citations omitted)).
We follow the approach of the Chapman Court, which looked for Congress’ intent in both section 841’s language and the legisla*1536tive history. Chapman, 500 U.S. at 460-61, 111 S.Ct. at 1924-25. The Court found that Congress “adopted a ‘market-oriented’ approach to punishing drug trafficking,” which punished according to the quantity distributed “rather than the amount of pure drug involved.” Id. at 461, 111 S.Ct. at 1925. Accordingly, Chapman found that “a carrier medium ... used to facilitate the distribution of the drug” was rationally included in the weight used to determine punishment. Id. at 466, 111 S.Ct. at 1928. Here, Chapman’s recognition of Congress’ “market-oriented” approach dictates that we not treat unusable drug mixtures as if they were usable.
Five circuits have distinguished between usable and unusable drug mixtures in interpreting “mixture” for purposes of section 841 and section 2D1.1. See United States v. Acosta, 963 F.2d 551, 554 (2d Cir.1992) (“[E]ven though the cocaine/creme liqueur may fall within the dictionary definition of ‘mixture,’ the legislative history convinces us that the weight of the creme liqueur must be excluded.”); United States v. Rodriguez, 975 F.2d 999, 1007 (3d Cir.1992) (“We find that the usable/unusable differentiation adopted by the Second, Sixth, Ninth, and Eleventh Circuits, rather than the First Circuit approach, best follows the reasoning in Chapman.”) -, United States v. Jennings, 945 F.2d 129, 136 (6th Cir.1991) (“[I]nterpreting the statute to require inclusion of the entire [mixture] for sentencing in this case would both produce an illogical result and be contrary to the legislative intent underlying the statute.”); United States v. Johnson, 999 F.2d 1192, 1196 (7th Cir.1993) (“To read the statute or Chapman as requiring inclusion of the weight of all mixtures, whether or not they are usable, ingestible, or marketable, leads to absurd and irrational results contrary to congressional intent.”); United States v. Rolande-Gabriel, 938 F.2d 1231, 1236 (11th Cir.1991) (“The Court in Chapman found that a plain meaning interpretation of “mixture” does not create an irrational result in the context of LSD and standard carrier mediums; however, in the present ease it would be irrational for the court to fail to distinguish between usable and unusable drug mixtures_”). See also United States v. Palacios-Molina, 7 F.3d 49, 53-54 (5th Cir.1993) (holding waste liquids in which cocaine was transported not a “mixture,” and distinguishing prior Fifth Circuit authority). But see United States v. Mahecha-Onofre, 936 F.2d 623, 625-26 (1st Cir.), cert. denied, 502 U.S. 1009, 112 S.Ct. 648, 116 L.Ed.2d 665 (1991); United States v. Sherrod, 964 F.2d 1501, 1509-10 (5th Cir.1992); United States v. Beltran-Felix, 934 F.2d 1075, 1076 (9th Cir.1991). This usable/unusable distinction has been applied by two circuits in the context of methamphetamine in waste water, see Jennings, 945 F.2d 129; United States v. Newsome, 998 F.2d 1571 (11th Cir.1993), and by two circuits in the context of cocaine waste water, see Johnson, 999 F.2d 1192; Palacios-Molina, 7 F.3d 49.
This interpretation of “mixture or substances” for statutory purposes also permits us to refer to the guideline definition and “adopt a congruent interpretation of the statutory term as an original matter.” Palacio, 4 F.3d at 154. Congress created the Sentencing Commission in 1984 and charged it with the task of “ ‘establishing] sentencing policies and practices for the Federal criminal justice system.’” Stinson v. United States, — U.S. -, -, 113 S.Ct. 1913, 1916, 123 L.Ed.2d 598 (1993) (quoting 28 U.S.C. 991(b)(1)). Commentary promulgated by the Commission is authoritative “unless it violates the Constitution or a federal statute, or is inconsistent with, or a plainly erroneous reading of, [the relevant] guideline.” Id. at 1915. Because of its sweeping authority and “significant discretion” in sentencing matters, Mistretta v. United States, 488 U.S. 361, 377, 109 S.Ct. 647, 657-58, 102 L.Ed.2d 714 (1989), we may draw on the Commission’s interpretations of federal sentencing standards when endeavoring to reach our own interpretation of a sentencing statute.
The Sentencing Commission specifically addressed the current issue in its amended commentary to section 2D1.1, clearly excluding the weight of waste water from the measurement of a “mixture or substance.” U.S.S.G. § 2D1.1 comment, n. 1. The commentary provides:
Mixture or substance does not include materials that must be separated from the controlled substance before the controlled substance can be used. Examples of such *1537materials include the fiberglass in a cocaine/fiberglass bonded suitcase, beeswax in a eoeaine/beeswax statue, and waste water from an illicit laboratory used to manufacture a controlled substance.
Id. The above examples mirror the facts of Killion and two First Circuit cases upon which it relies. Killion, 1 F.8d at 938 n. 10. In addition, the Sentencing Commission specifically stated its intent to resolve the inter-circuit conflict when it expressed its reasons to Congress for amending the commentary. See 58 Fed.Reg. 27148, *27155 (1993); Killion, 7 F.3d 927 (waste water); United States v. Lopez-Gil, 965 F.2d 1124 (1st Cir.) (cocaine/fiberglass bonded suitcase), cert. denied, — U.S. -, 113 S.Ct. 484, 121 L.Ed.2d 388 (1992); United States v. Restre-po-Contreras, 942 F.2d 96 (1st Cir.1991) (co-caine/beeswax statue), cert. denied, 502 U.S. 1066, 112 S.Ct. 955, 117 L.Ed.2d 123 (1992). In fact, Killion itself recognized the possibility that the amendment pending before the Commission would soon resolve the issue.7 7 F.3d at 931 n. 6 (citing 58 Fed.Reg. 27, 148 (1993) (to be codified at U.S.S.G.App. C, no. 484) (proposed May 6, 1993)).8
Adopting an interpretation opposite of the Sentencing Commission for purposes of applying the statutory mandatory minimum would lead to unnecessary conflict and confusion. We have recognized the importance of harmonizing the statutory penalty provisions and the sentencing guidelines. See United States v. Shewmaker, 936 F.2d 1124, 1128 (10th Cir.1991), cert. denied, 502 U.S. 1037, 112 S.Ct. 884, 116 L.Ed.2d 788 (1992); see also United States v. Shorthouse, 7 F.3d 149, 152 (9th Cir.1993) (“The statutory scheme of sentencing, including the [g]uide-lines, must be construed harmoniously as a whole.”), cert. denied, — U.S. -, 114 S.Ct. 1838, 128 L.Ed.2d 466 (1994). Furthermore, because the statutory mandatory minimum automatically becomes the guideline sentence when it is greater than the maximum of the applicable guideline range, see U.S.S.G. § 5Gl.l(b), allowing waste water to comprise a “mixture or substance” under the statute would effectively nullify the Commission’s policy choice.9 In light of this persuasive authority, we hold that section 841 does not include the weight of waste by-products in the measurement of a “mixture or substance.”
Citing United States v. Mueller, 27 F.3d 494 (10th Cir.1994), the government suggests that we must construe the mandatory minimum statute as it would have been construed at the time of sentencing, before the Sentencing Commission clarified the definition of “mixture or substance.” We interpret Mueller as foreclosing us from reducing a sentence below a mandatory minimum but *1538not mandating how the mandatory minimum statute will be interpreted. In Mueller, an LSD case, we were bound by Chapman’s interpretation of the mandatory minimum statute.10 Id. at 496. Here, we are free to interpret the statute as an issue of first impression. We are not required to interpret a statute in accordance with an outdated guideline and in conflict with the current, applicable guideline. We thus construe “mixture or substance” in section 841 to be consistent with the guideline commentary as • revised. In so doing, we join the majority of our sister circuits in adopting Congress’ market-oriented approach to drug sentencing as articulated in Chapman.
We AFFIRM the judgment of the district court.
.Section 841(b)(l)(A)(viii) provides a mandatory minimum of 10 years imprisonment for persons violating section 841(a) who possess "100 grams or more of methamphetamine ... or 1 kilogram or more of a mixture or substance containing a detectable amount of methamphetamine.”
Section 841(b)(l)(B)(viii) mandates a minimum sentence of five years for a person convicted under section 841(a) possessing "10 grams or more of methamphetamine ... or 100 grams or more of a mixture or substance containing a detectable amount of methamphetamine,”
. The Sentencing Guidelines determine sentencing levels based on the quantity of the drugs. In addition, they provide that "[i]n the case of a mixture or substance containing ... methamphetamine, use the offense level determined by the entire weight of the mixture or substance, or the offense level determined by the weight of the ... methamphetamine (actual), whichever is greater.” U.S.S.G. 2Dl.l(c).
. The court classified Mr. Richards at a level 38 under the Sentencing Guidelines because the total weight of the mixture containing the methamphetamine was 32 kilograms.
. On November 1, 1993, the following amendment to the Commentary of Sentencing Guidelines became effective: “Because the weights of LSD carrier media vary widely and typically far exceed the weight of the controlled substance itself, the Commission has determined that basing offense levels on the entire weight of the LSD and carrier medium would produce unwarranted disparity among offenses involving the same quantity of actual LSD (but different carrier weights), as well as sentences disproportionate to those other, more dangerous controlled substances, such as PCP. Consequently, in cases involving LSD contained in a carrier medium, the Commission has established a weight per dose of 0.4 milligram for purposes of determining the base offense level.” U.S.S.G., App. C, Amendment 488 (1994).
. The six circuits adopting this approach reasoned that "it is logical to include the weight of materials that are marketable or facilitate the marketability of the drug in question, and to exclude the weight of materials that do not.” United States v. Killion, 7 F.3d 927, 932 (10th Cir.1993). Those courts also based their interpretation on the fact that Congress, in enacting section 841, " ‘was concerned with mixtures that will eventually reach the streets — consumable mixtures.' ” Id. (quoting United States v. Rodriguez, 975 F.2d 999, 1006 (3d Cir.1992)).
. “Thus it is not enough for the judge just to use a dictionary. If he should do no more, he might come out with a result which every sensible man would recognize to be quite the opposite of what was really intended; which would contradict or leave unfulfilled its plain purpose.” Learned Hand, How Far Is a Judge Free in Rendering a Decision?, in The Spirit of Liberty 103, 106 (Irving Dilliard ed., 1952).
. We thus noted in Killion:
We do not address and leave open for consideration the possibility that the split among the circuits with respect to this question has been addressed by the United States Sentencing Commission. See 58 Fed.Reg. 27-148 (1993) (to be codified at U.S.S.G.App. C, no. 484 (proposed May 6, 1993)). In the event that the Commission chooses to give previously sentenced defendants the benefit of a new Guideline it is not our intention by this opinion to foreclose Killion from seeking appropriate relief.
7 F.3d at 931 n. 6.
. Indeed, when we rejected Mr. Richards’ second habeas petition as an abuse of the writ, we noted his argument that "a proposed amendment to the sentencing guidelines will retroactively apply to exclude the weight of the waste products in determining his sentence.” United States v. Richards, 5 F.3d 1369, 1372 n. 1. We then stated, "If the amendment does become effective and the Sentencing Commission does apply it retroactively, Richards may have a remedy under 18 U.S.C. § 3582(c)(2).” Id.
.In establishing the Sentencing Commission, Congress “sought reasonable uniformity in sentencing by narrowing the wide disparity in sentences imposed for similar criminal offenses committed by similar offenders.” U.S.S.G. Ch. 1, Part A.3 (policy statement).
In adopting the new commentary, the Commission attempted to implement this policy by eliminating highly disparate sentences for the same quantity of drugs. For example, prior to the new commentary, if the beeswax statue and the acrylic suitcase contained the same amount of cocaine but the suitcase weighed considerably more, the defendant with the suitcase would receive a much higher sentence. Under the new commentary, the defendants would be classified in the same sentencing range. If we adopt a conflicting interpretation of “mixture or substance,” the mandatory minimum would still impose a significantly higher sentence on the defendant with the suitcase. See also Chapman v. United States, 500 U.S. 453, 458 n. 2, 111 S.Ct. 1919, 1924 n. 2, 114 L.Ed.2d 524 (1991) (detailing disparate sentences imposed under Chapman).
. We have held that Chapman was deciding only the LSD issue. Killion, 7 F.3d at 934.