United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
                                   ___________

                                   No. 01-2899
                                   ___________

United States of America,               *
                                        *
                   Appellee,            * Appeal from the United States
                                        * District Court for the District
      v.                                * of Minnesota.
                                        *
Christopher Todd Casey,                 *     [UNPUBLISHED]
                                        *
                   Appellant.           *
                                   ___________

                             Submitted: February 12, 2002

                                 Filed: February 20, 2002
                                  ___________

Before McMILLIAN, FAGG, and RILEY, Circuit Judges.
                            ___________

PER CURIAM.

       Christopher Todd Casey, a clerk at Nutrition City, was convicted of selling a
controlled substance analogue, gamma-butyrolactone (GBL), in violation of 21
U.S.C. §§ 841(a)(1), 813, 802(32) (1994), and was attributed with the sale of 1,4-
butanediol under relevant conduct at sentencing. GBL is a central nervous system
depressant analogous to the controlled substance gamma-hydroxybutyric acid (GHB).
GHB is known for use as a date-rape drug. In the recent past, GBL was sold legally
in health stores under the trade names BLAST and Revivarant. Casey sold the
substances out of the store room, not the main floor, pocketed the proceeds, and did
not offer the buyer a receipt. At sentencing, Casey moved for a downward departure
under U.S. Sentencing Guidelines Manual § 5K2.0, arguing he did not know it was
illegal to sell GBL and 1,4-butanediol. In the alternative, Casey argued the quantity
was incorrectly calculated. The district court,* aware of its authority to depart,
declined to depart downward, adopted the presentence investigation report’s (PSR)
quantity calculation, and sentenced Casey to forty-six months imprisonment. Casey
now appeals his sentence.

       The law clearly holds that a district court’s decision not to depart downward
is unreviewable on appeal where the district court is aware of its authority not to
depart and does not do so. United States v. Riza, 

, 758 (8th Cir. 2001).
Because it is undisputed that the district court was aware of the ability to depart, and
exercised its discretion not to, we do not review Casey’s § 5K2.0 challenge. We
reject Casey’s second argument that district court incorrectly calculated drug quantity.
See United States v. Maggard, 

, 848 (8th Cir. 1998) (standard of review
is clear error). The drug quantity was correctly calculated as the Sentencing
Guidelines instruct, converting 0.5 grams of the liquid depressant to one unit.
U.S.S.G. § 2D1.1 n. (F). Besides, Casey’s argument is undermined by the labeling
instructions he provided in the appendix to his appellate brief. Casey argues one
ounce should equal one unit, rather than 0.5 grams equaling one unit, because one
ounce is the recommended dose of GBL. The labeling instructions, however, show
that quantities less than one ounce are also recommended doses; one ounce is the
recommended dose for sleep, one-half ounce is the recommended dose for daytime
use, and a “smaller serving” is the recommended dose for relaxation and mental
alertness.

      We affirm Casey’s sentence. See 8th Cir. R. 47B.



      *
       The Honorable Ann D. Montgomery, United States District Judge for the
District of Minnesota.

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A true copy.

      Attest:

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




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