United States
              Environmental Protection
            Office of
            Solid Waste and
            Emergency Response
IITLt.  Permitting of Refinery Oily Wastewater Treatment



ORIGINATING OFFICE: office of solid waste



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               A- Pending OMB approval
               B- Pending AA-OSWER approval "
           [ - ] ^ C- For review &/or comment . .
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REFERENCE (other documents):     headquarters
  OS WER      OS WER      OS WER

 CORRECTIVE ACTION.                                            DOC:  9502.01(84)

 Key Words:  '  Refinery  Wastes

 Regulations:  HSWA §206,  40  CFR 261.21-24

 Subject:       Permitting  of  Refinery  Oily Wastewater Treatment Ponds

 Addressee:    Robert  L. Duprey,  Director, Air  and Waste Management Division,
               Region  VIII

 Originator:    John H. Skinner,  Director, Office of Solid Waste                x

 Source  Doc:    #9502.01(84)

 Date:        -  12-07-84


     Downstream  unit  sludges from unlined wastewater ponds that treat or store
 oily wastewaters  are  similar to  those  found in the API separator but are not a
 sufficient basis  for  defining the material in  the downstream units as API
 Separator  Sludge.   The  Agency is planning to regulate oil/water/solids separation
 sludges generated  in  the  wastewater treatment  system prior to biological treatment

     There are three  ways to regulate  these pond sludges:

     1)  According  to HSWA §206, if a  refinery pond is releasing hazardous
         constituents and the refinery seeks a RCRA permit for any unit at  that
         facility,  the  refinery must  undertake corrective action for the releases
         from  the  pond.   (This  could  be done through the permit, or pursuant  to
         an  interim status compliance  order.)

     2)  The wastes could be regulated as hazardous if they exhibit one or  more
         of  the characteristics of hazardous waste (40 CFR 261.21-24).

     3)  Apply the  mixture rule  in cases where previously deposited sludge  from
., ._ _    a separator  is scoured,- resuspended and t-hen carried out of the unit-  -
         with  the wastewater.   The wastewater  becomes a hazardous waste until
         delisted or discharged  to a  stream subject to regulation under the
         Clean Water  Act.  The mixture rule cannot apply, however, where the
         API Separator is inefficient  and allows sludge to be carried  through
         to  a.pond, or where downstream oxidation ponds receive  flow that
         bypassed the API Separator.

         EPA bears  the burden of proof on the  demonstration of>the  application
         of  the scouring  argument.  This technically complex argument  can  be
         based on established scouring hydrodynamic principles.   HQ developed
         guidance to  facilitate  the application of the scouring  argument.   A
         list of  factors  was developed to evaluate whether scouring  from a given
         separation occurred.   The factors include:

         o   Sludge Accumulation  Practices          o   Separator  Effluent
         o   Flow Variability                           Characteristics
         o   Poor Separator Design or  Operations    o   Sludge  Characteristics


 SOBJECT-  Region  vin  poll-
"    ''     Oily  Wastewater  T
        •.•«—.««•"•          ' *.
    FROMs  John  H. Skinner. Dt
    :      Office  of  Solid  Waste  (WH-562)
      TO;  Robert  L.  Duprfey, Director
          Region  8   — -      -                     -
          Air and Wast2 Management Division (8AW-WM)
          -  i -. •' • •   • - - .

      We have reviewed  the  proposed Region VIII position
discussed in your memo* dated  May 1 and October  12. 1934 that
;deflne permitting coverage of  refinery wastevater traatjnent
ponds.  As your staff  »ay  have informed you, there have been
several meetings  between ay staff and yours to discuss this
problem.  We have also net with  Chevron. Phillips. Tosco and
API anrt, separately, with  Rag ion IX to discuss the issue.  We
share your concern about the  throat posed to ground and surface
waters by aooe  of the  unlined  wastewater ponds that treat  or
store oily wastevatera.  However, wo believe that the similarity
of downstream unit sludges (in terms of lead and chromium  levels)
to  those found  in the  API  Separator are not a sufficient basis
for defining the  material  in  the downstream units as API
Separator Sludge.  In  fact, the  similarity of these sludges was
a significant factor In our decision to nove forward on an .
expanded listing  to  regulate  these pond sludges.

      Specifically, we  are  planning in a forthcoming  listing  to
       e1 oi1/vater/solids  separation sludgos generated  in  the
           treatment system prior to biological  treatment.  This
listing was originally proposed  in Nov»»mb«»r of  I9fl0.   We  expect
to  issue a notice Identifying  all of the available  data  in support
of  the listing  and to  provide  sone clarifications  in response  to
previous comments.   Current plans are to proaulgata  that listing
by  lato summer.

      While the  listing revision  should  cov«?r nost  sludges generated
in these ponds, we realize that  does not address your short term
problem.  He do have some  suggestions  in this  regard.   Section
206 of the Hazardous .and Solid Waste Amendments of 1984 provides

   that persona obtaining RCRA permits must undertake  corrective
   action for all releases of hazardous constituents  from any
   solid waste management unit as a condition  of  obtaining the
   RCRA pnrait.  Thus, if a refinery pond Is releasing hazardous
   constituents and the refinery seeks a RCRA  permit  for any
   unit at that facility, the refinery would have to  undertake
   corrective action for the releases froa the pond.   (This could
   be done either through the permit, or pursuant to  an Interia
   status compliance order.)  This principle applies  even 1£  the
   pond is not considered to hold a hazardous  waste,  since Section
   206 Applies to releases of hazardous constituents  from solid
   waste management units.  ..«..,

•«•-•<**«• A second option for addressing these pond sludges Is  to
   regulate the wastes as hazardous based on their exhibiting one
   or more of the characteristics of hazardous waste  (see 40  CrR
   f261.21 -24).  You mentioned this option In your recent letter
   with respect to 8P Toxieity.  However, your staff  seems to have
   overlooked corroslvity (high pfl has been found in  some COO ponds)
   and reactivity ($261.23(a)(5)).  It Is likely  that some refinery
   pond sludges will contain excessive levels  of  reactive sulfldes.

 \      The final option that could be used to deal with downstream
  '- Impoundments and basins is applicability of the mixture rule.   It
   is imperative, however, that your staff understand the proper
   framework for the application of the mixture rule.   To maintain
   that a pond is regulated because an API Separator  is an inherently
   inefficient unit and allows sludge to bo carried through to  a
   pond, is Inaccurate.  Likewise, downstream  oxidation ponds are
   not regulated simply because they aoaetimes receive flow that
   has bypassed the API Separator.  In both cases, the listed API
   Separator Sludge has not yet been generated.  Rather, API
   Separator Sludge la generated when it is deposited in the  bottom
   of an API Separator.  The mixture rule is relevant only in those
   casos where previously deposited sludge is  scoured, reausponded,
   and then carried out of the unit with the wastawater.  If  the
   Region can make a case for scouring from a  separator, the  mixture
   rule ia applicable and the wastowater becones a hazardous'wasta
   until delisted or discharged to a stream subject to regulation
   under the Clean Water Act.

        The burden of proof in th« demonstration of scouring ia
   upon the Agency.  Such an argument, although technically complex,
   can be made based on well established hydrodynamic principles.
   Realizing that there are limited resources  and capability Cor
   developing such an arqument by the Regions, we have  (at the
   request of your staff) taken an active role in the development of
   guidance for the application of this argument.  Attached  to this
   mereo is a proliminary list of factors that nay be  required to
   establish the occurrence of scouring frora a given  separator.
   These points are being provided at thla time  to facilitate the
   initiation of information gathering  in the more serious cases.

      We hav«>  also requested  that th« Office  of  Waato Programs
 Enforcement  (OWP8)  develop nor* thorough  guidance.   That effort
 is being conducted  by their  contractor (Metcalf 6 Eddy).  We
 anticipate that your staff will be contacted by then in the near
 future   Ttie>  contractor should be able to provide so*e direct
 assistance to your  staff in  soara specific cases,  thereby serving
 the dual purpose of training and resolution  of  specific factors
 of concern.   Nike Barclay (PTS:   475-9727) of OWPE is the Read-
 quarters lead on that project and should  be  contacted for any
 further information.  Ben Smith of my staff  (PTSi   475-9531)  is
 our technical expert in this natter and the  lead on our study
 of petroleum  refineries and  their wastes.  Do not hesitate to
 contact hits  if additional questions arise pertaining to thla or
Bother natters.

 cc   RA'a Region I-X
      Hike Barclay (OWPE)
      Stevo Slvernan (OGC)
     •Susan Hanganello (ORC,  Region.VIII)

  Factors To Be Evaluated In Do terra in ing The potential for
                                              % *
                                               . j
                 Separator Sludge Scouring

 • Sludge Accumulation Practices - Continuous sludge removal"*
   from tho separator rules out the occurrence of scouring.
   At the other end of the spectrum are facilities that allow
 _•  sludge to accumulate to considerable depth.  Accumulation
 -"..  to a depth greater than 5O% of the flow depth makes scouring
 '  probable,  intermediate ranges of accumulation will prob- ...»..,
 -*, ably depend more heavily on other factors*        -" • '-- - - '
        Variablity - Unless overloaded, units with maximum-
   to-minimum, flow ratios at tho separator effluent of less
   than 2 and Inlet flow ratios of less than 4 are probably
^/- not experiencing 'much rosuspension of sludge.       .    .
?>"..     . •• •  '-'••-.'  ••-•.-••               '       ••-•".  •••"••"
'* Poor Separator Design or Operation - Factors contributing
;.•„•' to scour conditions include t  excessive, inlet or outlet.
 /.zone turbulence; nominal horizontal velocities greater  •
rr-"than 30 feet per minute; nominal overflow rates (flow/
7  -surface area)  greater. than 10,000 gallons per day/square
v foot of basin; basins less than 30 feet in length;  opera-
&'- t ion 'under pressure (e.g., with a backwater at the'  inlet
^  of a separator with a -frozen surface), settling zone
~  turbulence (sometimes seen as bubbling with solids
_.'- entrainment) .              "  '"   " '" ' '          \-

•',* Separator effluent Characteristics - Excessive weir loadings
   (e.g., operation with a suppressed weir, flow depth greater
   than a foot) facilitate carryover of resuspended  particles.
   Visible,  large (diameter greater than 1/4 Inch) sludge  •• .'.
• • particles in the separator effluent are strong evidence
   of scouring associated with microbial degradation of ^
   deposited sludge."

 • Sludge Characteristics - Particle size distribution as  "/..•*••
   measured  toy wot sieve and hydrometer analyses  is  necessary
   information to define scour conditions.  -The presence of -..
   coke fines in the wastewater influent is also  important
   because that size of particle  «.lmm) is non-cohesive
   and highly susceptible to rosuspension.