Unitwl States          t    Office of Water
  Envronmental Protection        4303                    July 1995
  Agency

                                                10058

 Fact    Sheet                        oğl  ?
 Proposed  Test  Procedure  for  the  Analysis  of  Oil
 and  Grease  and  Total   Petroleum  Hydrocarbons

 BACKGROUND

      The  discharge of chlorofluorocarbons  (CFCs)  has
 been  shown to be a primary contributor to the depletion
 of  the  earth's  stratospheric  ozone  layer.   The United
 States,  as  a  party  to  the  Montreal   Protocol  on
 Substances that Deplete the  Ozone Layer and as required
 by  law under  the Clean Air  Act Amendments  of 1990
 (CAAA),  is  committed  to controlling  and  eventually
 phasing out  CFCs.

      Freon-113  is a  Class  I CFC that is required  for
 use in  several U.S.  Environmental  Protection Agency
 (EPA) wastewater  methods for  the determination of  oil
 and grease  and  total petroleum  hydrocarbons  (TPH).
 Both  analytes  are  included   in  various   regulatory
 compliance   monitoring  programs  and  are  therefore
 measured on  a regular basis.

      As part of  the  effort to eliminate  the  use  of
 CFCs, EPA  studied the  use  of  solvents alternative  to
 Freon-113 for determination of oil and grease and TPH.
 As a result of these studies, EPA has concluded that n-
 hexane is the most suitable replacement for Freon-113
 in  the  separatory funnel extraction  and gravimetric
 determination of oil and grease and TPH.  Therefore EPA
 Method 1664: N-Hexane  Extractable Material (HEM)  and
 Silica Gel Treated N-Hexane  Extractable Material (SGT-
 HEM) by Extraction and Gravimetry (Oil and Grease and
 Total Petroleum Hydrocarbons)  is  being  proposed  to
 replace   currently    approved   methods    for   the
 determination of oil and grease and to provide a method
 for TPH.   Current 40  CFR  136 approved  methods  that
would be replaced by  Method  1664 include  EPA  Method
 413.1 and  Standard  Method  5520B, both  of  which use
 Freon-113  as the extraction solvent.

On  May  10,  1995, an  exemption  for laboratory and
analytical essential  uses of CFCs was granted  through
the 1997 control periods (60 FR 24970).  This proposed
rule will  provide for  the eventual elimination  of the

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                                                 p. 2
 elimination of the use of Freon-113 consistent with the
 goals of the CAAA and the Montreal  Protocol.

      The proposal of  Method  1664  is pursuant  to the
 authority of sections 301, 304(h), and  501(a)  of the
 Clean Water Act (CWA) . Test methods are promulgated at
 40  CFR Part 136.

 METHOD 1664

      Method 1664, which uses n-hexane as the extraction
 solvent in  place of  Freon-113,  is  a  liquid/liquid
 extraction, gravimetric procedure applicable to aqueous
 matrices for the determination of n-hexane extractable
 material and silica gel  treated n-hexane  extractable
 material (oil and grease and  TPH, respectively).

      The most  significant  changes  in  Method  1664
 compared to other oil  and  grease and TPH methods  that
 use   separatory   funnel   extraction  and  gravimetric
 determination  are  1) the use of  n-hexane  as   the
 extraction  solvent,  2) the use of standards of known
 composition and purity,   specifically  hexadecane  and
 stearic acid, as the spiking materials for QC analyses,
 and  3)  the  introduction  of extensive quality  control
 (QC) .  Though not specifically incorporated into Method
 1664,   the   use  of   alternative  extraction   and
 concentration   techniques,   such   as   solid  phase
 extraction  (SPE),  are allowed under the performance-
 based   option  of  this  method,  provided  that   all
 performance  specifications in the Method are met.

 REQUIREMENTS OF THE  REGULATION

      This proposal amends the Guidelines Establishing
 Test  Procedures  for  the  Analysis  of Pollutants under
 section  304(h)   of the  Clean  Water  Act  to  replace
 currently approved gravimetric test procedures with EPA
 Method  1664 for  determination  of  the  conventional
 pollutant  "oil   and  grease"  and  a  non-conventional
 pollutant,  TPH.    This  rule  is  necessary to  meet
 compliance monitoring  requirements of the Clean Water
 Act and, though the May 10, 1995 final rule concerning
 the protection of  the stratospheric ozone (60 FR 24970)
 provides a global exemption for  laboratory  use of CFCs
 through  1997, serves to  comply  with the CFC phaseout
 objectives of the Clean Air Act Amendments of 1990.

     This proposal solicits comments on the replacement
 of Freon-113 with n-hexane, the  utility of Method 1664
 for monitoring, the QC acceptance criteria,  the MDL and
ML levels,  and the performance-based  option criteria
 for the use  of alternative extraction and concentration
techniques,  such as SPE.   The  proposed rule applies to

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                                                 p. 3
any permits and regulations requiring the determination
of oil and grease by 40 CFR 136 approved methods.

REGULATORY IMPACTS

     Use  of  the  proposed method  will  affect  any
permittee regulated for oil and grease.  Since oil and
grease  is  a  method defined parameter,  any  change in
method protocol,  such  as  the  use of another solvent,
has the  potential to affect  results.   Evaluation of
results  generated  from  Phase  II  of  EPA's  Freon
Replacement Study, however, indicates that any change
in  oil  and grease concentration that may result from
using   n-hexane  instead   of  Freon-113   would  be
overshadowed  by  the  variability that was observed in
the pre-existing  approved Freon methods that did not
impose the thorough QC requirements imposed by Method
1613.    Therefore,   EPA   does  not  believe  that the
proposed change  in solvent will subject permittees to
a greater  risk of noncompliance than already exists.

     An    assessment   of   the   regulatory   impact
demonstrates that this  proposed regulation would not be
considered  a  major regulation.   The Agency believes
that  the  transitional  costs  associated  with  this
proposal will be minimal because laboratory  testing is
a very  small  part of Freon-113  consumption  (less than
I percent)  and  the testing required by EPA is only  a
fraction of this  total.   Furthermore, the rule is not
likely to cause a major increase in costs or  prices for
individuals  or consumers,  although laboratories may
experience some increase in costs due to longer testing
procedures because  of  the increased number of sample
manipulations and the additional quality control in the
method.    The regulation  is  also  unlikely  to  cause
significant adverse effects on competition, investment,
innovation, or  international  trade.

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