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Fw: DCGL Values and ALARA
> A little lengthy, sorry Melissa :-)
>
> I developed a decommissioning plan by combining four references which
> support each other quite well.
>
> 1. NUREG 1505
> 2. NUREG 1507
> 3. MARSSIM
> 4. DG-4006
>
> ****NUREG 1506 (I did not use it but is out there. Still hunting for
> it!)
> And of course the good old DandD computer code.
>
> Site characterization, history of use, etc. is a very important part. It
> all comes down to that say "Know your radionuclides" Once this phase was
> completed I used DandD ( building occupancy scenario) to calculate the
> average DCGL [dpm/cm^2] per radionuclide that would give 25mrem (TEDE) to
an
> occupant in the first year.
>
> These NUREGs will also help you to take the now available DCGLs and
combine
> them into one general DCGL which is very convenient at the time of
> surveying. You will also find a good review on how to account for the
> equipment's effective surveying area and the MDC to include the operators
> technique (static or scanning).
>
> Once you classified the site (1,2, or 3), made the appropriate sample grid
> (if required) and got your readings go to DandD and plug it in. The
NUREGs
> also states that is best not to mess around with the model parameters (if
> you do you have to explain/justify your decision).
>
> If the model estimates less than 25mrem your done with that part. For the
> ALARA criteria, I think it is DG-4006 that says; "the ALARA criteria is
met
> by the action of lowering the contamination levels, not by reaching an
> specific target limit" (or something like that). When I conducted a
> decommissioning plan and met the 25mrem criteria, I just performed a good
> clean up, enough to lower the initial readings. Good planning proved to
be
> a key instrument. Oh, and forget about using wipes to prove the
> unrestricted release criteria as per 10CFR20.1402!
>
> I tried once to use Reg Guide 1.86 but lucky enough I found DG-4006 and
the
> rest is history. For example 1.86 sets the limit for I-125 at 20
dpm/cm^2.
> If you estimate the limit with DandD is a lot higher. I still think it is
> good for releasing equipment for unrestricted use.
>
> Nestor
> nestorruiz@earthlink.net
>
> ----- Original Message -----
> From: Nardi, A. Joseph <nardiaj@westinghouse.com>
> To: Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
> Sent: Friday, September 17, 1999 11:53 PM
> Subject: RE: DCGL Values and ALARA
>
>
> > If your Decommissioning Plan has been approved by the NRC and
incorporates
> > the approval to utilize the Reg Guide 1.86 values, then they become your
> > DCGL's. You do not have to mix in the new regs and the 25 mrem limit if
> > your approval does not require it.
> >
> >
> > A. Joseph Nardi
> > Supervisory Engineer
> > Environment, Health and Safety
> > Westinghouse Electric Company
> > Phone: (412) 374-4652
> > Email: nardiaj@westinghouse.com
> >
> > > ----------
> > > From: Johannes Strydom[SMTP:fritz.strydom@ors.gatech.edu]
> > > Reply To: radsafe@romulus.ehs.uiuc.edu
> > > Sent: Friday, September 17, 1999 3:01 PM
> > > To: Multiple recipients of list
> > > Subject: DCGL Values and ALARA
> > >
> > > This is a multi-part message in MIME format.
> > >
> > > ------=_NextPart_000_0001_01BF00FB.1C108820
> > > Content-Type: text/plain;
> > > charset="iso-8859-1"
> > > Content-Transfer-Encoding: 7bit
> > >
> > > Radsafers,
> > >
> > > As many of you may be aware, we are in the process of decommissioning
> our
> > > research reactor here at Georgia Tech. We are decommissioning to Reg
> > > Guide
> > > 1.86 levels (Not MARSIMM).
> > >
> > > We are trying to find a method by which we can determine in what areas
> our
> > > money would best be spent to perform further decontamination after
1.86
> > > levels have been met. The NRC put out a working Reg guide on ALARA
> > > Analysis
> > > that outlines a method to perform a determination on when further
> > > decontamination would be economically reasonable. In order to use
their
> > > equations, it is necessary to have DCGL values for both surface
> > > contamination and volumetric contamination.
> > >
> > > The DCGL is the average concentration of residual activity that would
> give
> > > a
> > > dose of 25 mrem/yr to the average member of the population in units of
> > > activity per unit area for buildings or activity per unit volume for
> > > soils.
> > >
> > > Does anyone know of a place where (or has someone calculated) I can
get
> > > generic DCGL (Derived Concentration Guideline) values for common
> > > radionuclides in such things as concrete, building surface
> contamination,
> > > soil, etc for a building that is decommissioned to free release. From
> > > what
> > > I have read, it seems that to get these numbers, an analysis using
> > > software
> > > such as Resrad needs to be done. We can certainly do this if
necessary,
> > > but
> > > I was wondering if there was a generic table somewhere?
> > >
> > > Thank you.
> > >
> > > ------------------------------------------------
> > > Johannes "Fritz" Strydom
> > > Health Physicist
> > > Georgia Institute of Technology
> > > (404) 894-3605
> > > (404) 894-9325 fax
> > > fritz.strydom@ors.gatech.edu <mailto:fritz.strydom@ors.gatech.edu>
> > >
> > >
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> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'>Radsafers,<o:p></o:p></span></font></span></p>
> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'><![if =
> > >
!supportEmptyParas]> <![endif]><o:p></o:p></span></font></span></p>
> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'>As many of you may be aware, we are in the process of =
> > > decommissioning
> > > our research reactor here at Georgia Tech.<span style=3D"mso-spacerun:
=
> > > yes">=A0
> > > </span>We are decommissioning to Reg Guide 1.86 levels (Not =
> > > MARSIMM).<o:p></o:p></span></font></span></p>
> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'><![if =
> > >
!supportEmptyParas]> <![endif]><o:p></o:p></span></font></span></p>
> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'>We are trying to find a method by which we can determine in
what
> =
> > > areas our
> > > money would best be spent to perform further decontamination after
1.86
> =
> > > levels
> > > have been met.<span style=3D"mso-spacerun: yes">=A0 </span>The NRC put
=
> > > out a
> > > working Reg guide on ALARA Analysis that outlines a method to perform
a
> > > determination on when further decontamination would be economically =
> > > reasonable.<span
> > > style=3D"mso-spacerun: yes">=A0 </span>In order to use their
equations,
> =
> > > it is
> > > necessary to have DCGL values for both surface contamination and =
> > > volumetric
> > > contamination.<o:p></o:p></span></font></span></p>
> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'><![if =
> > >
!supportEmptyParas]> <![endif]><o:p></o:p></span></font></span></p>
> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'>The DCGL is the average concentration of residual activity that
=
> > > would
> > > give a dose of 25 mrem/yr to the average member of the population in =
> > > units of
> > > activity per unit area for buildings or activity per unit volume for =
> > > soils.<o:p></o:p></span></font></span></p>
> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'><![if =
> > >
!supportEmptyParas]> <![endif]><o:p></o:p></span></font></span></p>
> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'>Does anyone know of a place where (or has someone calculated) I
=
> > > can get
> > > generic DCGL (Derived Concentration Guideline) values for common =
> > > radionuclides
> > > in such things as concrete, building surface contamination, soil, etc
=
> > > for a
> > > building that is decommissioned to free release.<span =
> > > style=3D"mso-spacerun:
> > > yes">=A0 </span>From what I have read, it seems that to get these =
> > > numbers, an
> > > analysis using software such as Resrad needs to be done.<span
> > > style=3D"mso-spacerun: yes">=A0 </span>We can certainly do this if =
> > > necessary, but I
> > > was wondering if there was a generic table =
> > > somewhere?<o:p></o:p></span></font></span></p>
> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'><![if =
> > >
!supportEmptyParas]> <![endif]><o:p></o:p></span></font></span></p>
> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'>Thank you.<o:p></o:p></span></font></span></p>
> > >
> > > <p class=3DMsoNormal><span class=3DEmailStyle15><font size=3D2 =
> > > color=3Dblack
> > > face=3DArial><span =
> > > style=3D'font-size:10.0pt;mso-bidi-font-size:12.0pt;font-family:
> > > Arial'><![if =
> > >
!supportEmptyParas]> <![endif]><o:p></o:p></span></font></span></p>
> > >
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> color=3Dblack><span=20
> > > style=3D'color:black'><span =
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> style=3D'color:black'>------------------------------------------------</s=
> > > pan></font><font
> > > color=3Dblack><span =
> > >
> style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font><=
> > > /p>
> > >
> > > <p class=3DMsoAutoSig><font size=3D3 color=3Dblack face=3D"Times New =
> > > Roman"><span
> > > style=3D'font-size:12.0pt;color:black'>Johannes "Fritz" =
> > > Strydom</span></font><font
> > > color=3Dblack><span =
> > >
> style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font><=
> > > /p>
> > >
> > > <p class=3DMsoAutoSig><font size=3D3 color=3Dblack face=3D"Times New =
> > > Roman"><span
> > > style=3D'font-size:12.0pt;color:black'>Health =
> > > Physicist</span></font><font
> > > color=3Dblack><span =
> > >
> style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font><=
> > > /p>
> > >
> > > <p class=3DMsoAutoSig><font size=3D3 color=3Dblack face=3D"Times New =
> > > Roman"><span
> > > style=3D'font-size:12.0pt;color:black'>Georgia Institute of =
> > > Technology</span></font><font
> > > color=3Dblack><span =
> > >
> style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font><=
> > > /p>
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> > > <p class=3DMsoAutoSig><font size=3D3 color=3Dblack face=3D"Times New =
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> > > style=3D'font-size:12.0pt;color:black'>(404)
894-3605</span></font><font
> > > color=3Dblack><span =
> > >
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> > > style=3D'font-size:12.0pt;color:black'><a
> > >
> href=3D"mailto:fritz.strydom@ors.gatech.edu";>fritz.strydom@ors.gatech.edu=
> > > </a></span></font><font
> > > color=3Dblack><span =
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> style=3D'color:black;mso-color-alt:windowtext'><o:p></o:p></span></font><=
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