Title  : Use of 51Cr by S-035
Type   : Antarctic EAM
NSF Org: OD / OPP
Date   : September 02, 1992
File   : opp93072



                                       DIVISION OF POLAR PROGRAMS
                                        OFFICE OF THE ENVIRONMENT
                                                     202/357-7766
MEMORANDUM

   Date:  September 2, 1992

   From:  Environmental Officer, DPP

Subject:  Environmental Action Memorandum (Approval / Use of
            51Cr by S-035)

     To:  Manager, Polar Biology and Medicine Program, DPP
          Associate Manager, Polar Biology and
            Medicine Program, DPP
          Manager, Science Projects, DPP
          Files (S.7.1 - Environment/Hazardous Waste)







Earlier this year, S-035 proposed the use of the gamma-emitting
radioisotope 51Cr during the 1992-1993 austral summer research
season.  The proposed research would take place at an isolated
offshore sea ice hole near McMurdo Station.  The Manager, Polar
Biology and Medicine Program, DPP, raised concerns about, and
sought advice on, the proposed use of this relatively energetic
gamma-emitter.  She requested further information from the
Principal Investigator on the proposed use to allow evaluation by
the Environmental Officer, DPP.  The Principal Investigator
provided a response on August 13, 1992.

The Environmental Officer reviewed the response and believes that
the Principal Investigator has described in an adequate manner:
1) the rationale for such use; 2) his consideration of alterna-
tives; 3) the potential impact of any release of 51Cr to the
environment; and 4) how wastes from the proposed study will be
handled by the U.S. Antarctic Program (note from Attachment that
seal carcasses would be disposed of at sea while all other
radioactive waste would be retrograded from Antarctica).

                             Finding

51Cr ia a relatively energetic gamma-emitter with a half-life of
27.8 days.  The total dose to be used would be ~1.25 mCi.
Accepted radioisotope technique recognizes that after approxi-
mately 10 half-lives (~278 days), virtually all of any 51Cr
released to the environment through carcass disposal would be
decayed.  The Environmental Officer believes that in light of the
potential value of the proposed research such release is
justifiable.  Also, he believes that such release can be expected
to have less than minor and less than transitory effects on the
environment.  The Environmental Officer authorizes the use of
51Cr as proposed by S-035.





                                 Sidney Draggan

Attachment
  Zapol Letter of August 13, 1992, to Penhale

cc:  Warren M. Zapol, S-035