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4i South Coast Plaza Hydrogen Sulfide Reduction Program Costa Mesa Sanitary District …an Independent Special District Protecting our community’s health and the environment by providing solid waste and sewer collection services. www.cmsdca .gov Memorandum To: Board of Directors From : Scott Carroll, General Manager Date: February 18, 2014 Subject: South Coast Plaza Hydrogen Sulfide Reduction Program Summary For the past two years the District, along with Environmental & Engineering Contrac ting, Inc. (EEC) and South Coast Plaza (SCP) management, have been developing procedures to reduce hydrogen sulfide levels (H2S) in the District owned sewer lift station located on Plaza prope r ty. H2S is a gas that often results from the bacterial breakdown of organic matter in the absence of oxygen , such as in sewer systems. It has caused severe corrosion in the lift station and it will emit a rotten egg smell in the atmosphere that has resulted in complaints from Plaza customers. Staff Recommendation That the Board of Directo rs give staff dire ction to bringing South Coast Plaza restaurants Boudin Bakery, Corner Bakery Café and Marche Moderne into compliance with their wastewater permitted discharge limits. Analysis In 2012 , the Dist rict embarked on a case study at SCP to determine if chemicals addi tives are proven effective to reducing sulfide levels in grease interceptors . In the past, the District has applied chemicals in the lift station wet well that has been helpful masking the odor; however, the objective of the study was to identify fea sible options for effectively mitigating the wastewater sulfides at the source (e.g. grease interceptors) so that odor and corrosion is minimized at the station and the District can optimize its resources at the lift station . EEC, with the co operation fro m SCP management, conducted the case study. The results found that ev en though there was not a specific chemical additive that had extraordinary results to re ducing sulfide levels, the additives used did prove to be effective for mitigating Board of Directors February 18, 2014 Page 2 of 3 dissolved sulfi de levels in grease interceptors . Additional recommendations were made by EEC and can be found in the case study attached hereto at Attachment A. EEC representatives will be attending today’s study session to provide more inf ormation about the case study and will be available to answer questions. It should be noted that since the study was conducted Rainforest Café has closed its do ors at SCP and a new restaurant will take its place. EEC has provided recommendations to SCP management on the right sized grease interceptor installation for the new tenant. As of January 2014 SCP has not indicated that the grease interceptor will be resized, or when a new tenant will occupy the old Rainforest Café space. Staff and EEC presented the findings of the study to SCP management and after further discussion the group developed procedures to roll out the program to every restauran t in the Plaza. In March 2013 the District and SCP management delivered simultaneously two separate letters about the new procedures for r educing H2S lev els. The District letter, the sample is attached hereto as Attachment B , describes the problem and provided suggested corrective actions including use of the chemical additives evaluated in the study . The SCP management letter described th eir support for the procedures and encouraged restaurants to comply with District standards. Both letters were mailed to seventeen restaurants in the Plaza. The list of restaurants is available in Attachment C. By November 2013 , EEC identified three res taurants with sulfide levels that are still above their permitted discharge limits. Those three restaurants are: Boundin Bakery, Corner Bakery and Marche Moderne. On November 15, 2013, District mailed follow up letters to the restaurant managers expressin g the importance to reducing sulfide lev els and requested immediate implementation of corrective actions to reduce the levels by December 20, 2013 (See letters in Attachment D); however, when EEC conducted a follow -up inspection on December 30, 2013 , EEC f ound these restaurants had not implemented any corrective actions and were still in noncompliance. Therefore, s taff believes t he District has three options to consider : 1. Do nothing. 2. Send another follow up letter. 3. Issue an administrative citation in the am ount of $250. Option three would require staff to follow the guidelines outlined in Chapter 1.06 of the District’s Operations Code. Currently, the District’s Enforcement Officer has the authority to issue administrative citations . After issuing the cita tion, the restaurants have a right for due process where they can request an administrative hearing, but the fine must be paid in full before scheduling said hearing . The General Manager serves as the hearing officer ; however, due t o my involvement in the hydrogen sulfide program at SCP, I would most likely appoint someone that is not involve d in the program to avoid possible claims that the hearing officer is bias and/or prejudice. Board of Directors February 18, 2014 Page 3 of 3 Strategic Plan Element & Goal This item supports achieving Strategic El ement No. 1 .0, Sewer Infrastructure and Strategic Goal No. 1.7, Pump Station Maintenance & Standardization Program. Legal Review Not applicable at this time; however, District Counsel may be required if administrative hearings are scheduled. Environment al Review A program to reduce hydrogen sulfide odors and the resulting corrosion in private and public sewer systems is categorically exempt under the California Environmental Quality Act (CEQA) (Public Resources Code Section 21000 et. seq.) under Section 15301 Existing Facilities as “Class 1 consists of the … maintenance … of existing public or private structures”, as further described in Section (b) as “Existing facilities of both investor and publicly -owned utilities used to provide …. sewerage …” Finan cial Review The cost to perform the case study was $7,670 . In addition, it has cost the District $2,055 to implement the new procedures for reducing hydrogen sulfide levels at South Coast Plaza. Public Notice Process Copies of this report are on file and will be included with the entire agenda packet for the February 18, 2014 Bo ard of Directors study session at District Headquarters and on District website. Alternative Actions 1. Refer the matter back to staff for additional information. Attachments A : Case Study B: Sample Letter to SCP restaurants C: List of SCP restaurants D: Letters to Boudin Bakery, Corner Bakery Café, and Marche Moderne Gre a C a se In t C ase St u Co s Envir o t ercep t u d y at s ta M e Nov e Pr Costa  Me s  628  W Costa  Me s P r o nmental  En g 501  P a Santa  An a EEC  W t or Sul f South e sa, Ca l e mber  5, 201 2             epared  for:  s a  Sanitary  D W  19th  Stre e s a, California    r epared  by:   g ineering  & C o a rkcenter  Dri v a , California  9 W 2263.02 ‐M A f ide M i Coast l iforni a 2  istrict  e t  92627  o ntracting, I n v e  9 2705  A i tigati o Plaza a n c. o n Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  i  EEC  TABLE OF CONTENTS  1.0   INTRODUCTION   ............................................................................................................................... 1  2.0   OBJECTIVES  ...................................................................................................................................... 1  3.0  BACKGROUND  .................................................................................................................................. 1   3.1   Sewer  Odors  ........................................................................................................................ 1   3.2   Historical  Odor  Issues  / Mitigation  Efforts  .......................................................................... 3   3.3   Study  Area  ........................................................................................................................... 4  4.0   FIELD  ACTIVITIES  .............................................................................................................................. 5   4.1   Wastewater  Sampling  and  Visual  Observations  ................................................................. 6    4.1.1  Airborne  Hydrogen  Sulfide  Gas  ............................................................................. 7    4.1.2  Dissolved  Sulfide  .................................................................................................... 7    4.1.3  Temperature/pH  .................................................................................................... 8   4.2   Maintenance  Condition  Assessment  .................................................................................. 8  5.0   FINDINGS/RESULTS  .......................................................................................................................... 7   5.1   Boudin  SF  ............................................................................................................................ 9   5.2   Rainforest  Café  .................................................................................................................. 10   5.3  Corner  Bakery  ................................................................................................................... 11   5.4  Marche  Moderne  .............................................................................................................. 12   5.5   Claim  Jumper  .................................................................................................................... 13   5.6   Z’Tejas  ............................................................................................................................... 14   5.7  Capital  Grille  / Seasons  52  ................................................................................................ 16   5.8   Summary  ........................................................................................................................... 17  6.0   RECOMMENDATIONS  .................................................................................................................... 18   TABLES Table  4 ‐1  EEC  Field  Visits  to  Date  ....................................................................................................... 6  Table  5 ‐1  Boudin  SF  Gravity  Grease  Interceptor  Results  .................................................................... 9  Table  5 ‐2  Rainforest  Café  Gravity  Grease  Interceptor  Sampling  Results  ......................................... 10  Table  5 ‐3  Corner  Bakery  Gravity  Grease  Interceptor  Sampling  Results  ........................................... 11  Table  5 ‐4  Marche  Moderne  Gravity  Grease  Interceptor  Sampling  Results  ...................................... 13  Table  5 ‐5  Claim  Jumper  Gravity  Grease  Interceptor  Sampling  Results  ............................................ 14  Table  5 ‐6  Z’Tejas  Gravity  Grease  Interceptor  Sampling  Results  ....................................................... 15  Table  5 ‐7  Capital  Grille  / Seasons  52  Gravity  Grease  Interceptor  Sampling  Results  ........................ 16   FIGURES  Figure  3 ‐1  H 2 S  Toxicity  Spectrum  ......................................................................................................... 2  Figure  3 ‐2   H 2 S  Gas  Concentrations, Airborne  vs. Dissolved  ................................................................ 3  Figure  3 ‐3  Locations  of  Gravity  Grease  Interceptors  at  South  Coast  Plaza  ......................................... 5  Figure  4 ‐1  Sample  Point  Locations  within  Gravity  Grease  Interceptors  .............................................. 7  Figure  4 ‐2  CHEMetricts  R ‐9510  Colorimetric  Field  Tester  ................................................................... 7  Figure  4 ‐3  Wastewater  Core  Sampler  .................................................................................................. 8  Figure  5 ‐1  Corner  Bakery  Sample  Box  ................................................................................................ 12  Figure  5 ‐2  Z’Tejas  Sample  Box  ........................................................................................................... 15   Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  1  EEC  1.0 INTRODUCTION  For  years, the  Costa  Mesa  Sanitary  District  (District) has  worked  in  cooperation  with  the  South  Coast  Plaza  (Plaza) to  address  sewer  odor  and  corrosion  issues  within  the  Plaza, particularly  in  areas  associated  with  the  District’s  South  Coast  Plaza  pumping  station, located  at  the  northeast  corner  of  the  south  parking  structure  (see  Figure  3 ‐3). The  District, which  owns  the  public  sewer  system  serving  the  Plaza, has  taken  measures  to  mitigate  the  odor  issues  through  the  use  of  chemical  additives, frequent  cleaning  of  the  lift  station, and  upgrades  to  the  sewage  lift  station. The  Plaza  has  also  taken  measures  to  mitigate  the  odor  issues, including  installation  of  a  vent  blower  at  the  lift  station  and  evaluation  of  chemical  additives  (applied  at  several  of  the  grease  interceptors  tributary  to  this  lift  station).    Each  of  these  measures  has  helped  to  reduce  the  occurrence  of  reported  odors; however, the  measures  have  not  fully  mitigated  the  issue. To  further  characterize  the  sources  of  the  corrosion  and  odor  issues  and  evaluate  the  effectiveness  of  available  chemical  additives  for  mitigation  of  these  issues, the  District  commissioned  Environmental  Engineering  and  Contracting, Inc. (EEC) to  conduct  a  study  of  the  wastewater  from  the  grease  interceptors  discharging  to  the  Plaza  lift  station. The  study  consisted  of  field  data  collection  and  analysis  of  wastewater  generated  under  various  site  conditions, coordinated  with  the  application  of  a  variety  of  chemical  additives. EEC  has  prepared  this  report  to  summarize  the  findings  from  the  study  and  provide  recommendations  for  follow ‐up  actions  to  effectively  mitigate  the  sulfide  issues  at  the  Plaza.   2.0 OBJECTIVES  The  District  and  Plaza  have  been  diligent  in  their  efforts  to  address  sulfide  issues. Generally, the  implemented  corrective  measures  to  date  have  been  helpful  in  masking  the  symptom  (i.e., sulfide  odors); however, efforts  to  mitigate  the  cause  (i.e., sulfide  generation  in  grease  interceptors) have  not  yet  proven  consistently  effective.  The  objective  of  this  study  is  to  identify  feasible  options  for  effectively  mitigating  the  wastewater  sulfides  at  the  source, thereby  reducing  the  potential  for  nuisance  odor  issues  and  optimizing  the  resources  required  to  continue  mitigation  of  these  issues  further  downstream  in  the  Plaza  lift  station  and  downstream  sewer  system.   3.0 BACKGROUND 3.1 Sewer Odors Hydrogen  sulfide  ( H 2 S) is  a  colorless  gas  that  is  commonly  identified  in  low  concentrations  (less  than  1  decaying  organic  material, particularly  under  low ‐oxygen  conditions; therefore, H 2 S  is  commonly  encountered  in  places  such  as  grease  interceptors, sewer  pipelines, and  sewage  lift  stations. Unmitigated, H 2 S  poses  a  potential  health  risk  for  sewer  maintenance  personnel, causes  damage  (corrosion) to  sewer  system  structures, and  is  a  source  of  nuisance  odors  to  the  general  public  (Figure   3 ‐1, H 2 S  Gas  Toxicity  Spectrum ).    Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  2  EEC Figure 3 ‐1, H 2 S Gas Toxicity Spectrum   The  wastewater  from  the  sinks, drains, and  cooking  equipment  of  many  of  the  Plaza’s  food  service  establishments  (FSEs) flows  into  grease  interceptors  prior  to  discharging  to  the  District's  sanitary  sewer  system. Each  grease  interceptor  provides  a  separation  method  whereby  the  fats, oils, and  grease  (FOG) in  the  wastewater  floats  and  collects  on  top  of  the  water, and  the  food  solids  in  the  wastewater  settle  and  collect  at  the  bottom. The  floating  FOG  and  settled  solids  are  removed  during  routine  cleaning  of  the  grease  interceptor. The  wastewater  from  the  grease  interceptor  (which  is  largely  free  of  FOG/solids) flows  into  the  sanitary  sewer  system. Depending  on  the  amount  and  type  of  FOG/solids ‐laden  wastewater  that  is  rinsed  down  the  FSE  kitchen  drains, grease  interceptor  size  and  maintenance  condition, and  other  characteristics, such  as  wastewater  temperature  and  acidity  (pH), each  grease  interceptor  has  the  potential  to  generate  sulfides. Larger, oversized  grease  interceptors  are  more  susceptible  to  becoming  sources  of  sulfides, but  smaller  interceptors  can  also  experience  sulfide  issues. The  sulfides  generated  under  these  conditions  are  dissolved  within  the  wastewater, but  are  easily  released  from  solution  through  agitation  or  mixing. When  it  flows  from  its  source  to  downstream  pipelines  and  structures  (lift  stations, manholes, etc.), sulfide ‐laden  wastewater  is  naturally  agitated  and  mixed, which  releases  the  H 2 S  gas  and  results  in  sulfide  odors. The  H 2 S  gas  also  combines  with  moisture  in  the  air  to  create  sulfuric  acid, which  corrodes  grease  interceptor  surfaces  and  other  sewer  system  structures.   Under  certain  conditions, low  levels  of  dissolved  sulfide  can  result  in  very  high  levels  of  airborne  H 2 S  . As  an  example, within  a  sewer  pipeline, the  sewer  atmosphere  can  exhibit  very  high  concentrations  of  H 2 S  gas  associated  with  low  concentrations  of  dissolved  H 2 S, as  depicted  in  Figure  3 ‐2, H 2 S  Gas  Concentrations, Airborne  vs. Dissolved  (Pipeline  Atmosphere  Example).          Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  3  EEC Figure 3 ‐2, H 2 S Gas Concentrations, Airborne vs. Dissolved    Key:  °C  = degrees  Celsius   H 2 S  = hydrogen  sulfide  mg/l  = milligrams  per  liter  ppm  = parts  per  million   To  minimize  and  prevent  the  negative  impacts  caused  by  H 2 S  that  include  potential  health  risks, corrosion, and  nuisance  odors, the  District  has  established  H 2 S  ‐related  compliance  criteria:   Dissolved  sulfide  must  not  exceed  0.5  mg/L  (based  on  OCSD  wastewater  discharge  limit)  Airborne  H 2 S  must  not  exceed  1  ppm  (below  typical  offensive  odor  threshold)  3.2 Historical Odor Issues / Mitigation Efforts  Due  to  the  elevation  of  the  southeast  section  of  the  Plaza, including  several  FSEs, wastewater  from  this  section  needs  to  be  pumped  to  the  District’s  public  sewer  system; the  pumping  station  is  known  as  the  South  Coast  Plaza  lift  station. Historically, the  Plaza  lift  station  has  been  identified  as  the  source  of  sulfide  odor  issues. To  mitigate  these  issues, the  District  has  implemented  the  following  corrective  measures:   Enhanced  cleaning  program  for  the  lift  station   Chemical  additive  (Golden  Bio) application  at  a  cost  to  the  District  of  $1,200  to  $1,800  per  month   Installation  of  a  down ‐drain  inlet  configuration  to  reduce  turbulence  (agitation) within  the  lift  station  and  minimize  the  release  of  sulfide  gases  from  the  wastewater    Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  4  EEC The  Plaza  has  also  implemented  corrective  measure  to  mitigate  the  lift  station  odor  issues:   Installation  of  a  vent  blower  to  disperse  the  sewer  gases  emanating  from  the  lift  station   Application  and  evaluation  of  grease  interceptor  applied  chemical  additives  (in  coordination  with  District  interceptor  inspection  activities)  Generally, both  the  District’s  and  Plaza’s  corrective  measures  have  been  helpful  in  masking  the  symptom  (i.e., sulfide  odors); however, these  efforts  have  not  been  effective  at  consistently  mitigating  the  cause  (i.e., sulfide  generation  in  grease  interceptors) for  the  long  term.   3.3 Study Area  South  Coast  Plaza  is  a  large ‐scale  shopping  mall  located  in  Costa  Mesa, California. The  Plaza  contains  several  FSEs  that  typically  operate  between  the  hours  of  8:00  a.m. and  11:00  p.m.; several  of  the  FSEs  are  connected  to  gravity  grease  interceptors  (GGIs) within  the  Plaza  property. This  study  evaluated  the  GGIs  in  the  southeast  section  of  the  Plaza  that  discharge  to  the  Plaza  lift  station  (Figure  3 ‐3, Locations  of  Gravity  Grease  Interceptors  at  South  Coast  Plaza ):   Boudin  SF  (1,500 ‐gallon  GGI)  Rainforest  Café  (3,500 ‐gallon  GGI)  Corner  Bakery  (1,500 ‐gallon  GGI)  Claim  Jumper  (2,000 ‐gallon  GGI)  Z ‐Tejas  (750 ‐gallon  unit)  Capital  Grille  / Seasons  52  (share  a  4,000 ‐gallon  unit)  Grease  Inte W1425.010  In  additi o study  ev e evaluatio n  Two  of  t structure s parking  l o 4.0 F  Sulfide  l e wastewa t routinely  ware/eq u rceptor  Sulfide  M Costa  Mesa  Sa n Figure 3 ‐o n  to  these  s e n  though  it n  activities  (c he  GGIs  (Ra s , one  is  loca t o t  areas  (Figu IELD ACTI V e vels  within  t er  resides  i n discharged  u ipment  was h M itigation  Stud y n itary  District  ‐3, Locatio n ix  facilities, t  does  not  d ommissione d inforest  Caf é t ed  in  an  out s r e  3 ‐3).  V ITIES grease  inte n  the  interc e to  the  gr e h ing  activitie s y  at  South  Coast  n s of Grav i t he  Marche  M ischarge  to  d  by  the  Plaz a é  and  Corne s ide  planter  (rceptor  was t ptor  (retent i e ase  interc e s . This  flow  o f Plaza 5 ty Grease I M oderne  fac i the  Plaza  lif t a ) were  alrea d r  Bakery) ar e Claim  Jumpe t ewater  can  i on  time). D u e ptor  as  a  f  water  brin g I ntercepto r i lity  (1,500 ‐g a f t  station  be c d y  in  progres s e  located  o n r), and  the  r e be  affecte d u ring  restau r result  of  a g s  added  oxy g r s at Sout h a llon  GGI) w a c ause  some  s . n  the  groun d e maining  are  d  by  the  le n r ant  operati o a ctive  food  g en  (dissolve November  5 h Coast Pla z a s  included  i chemical  ad d  floor  of  p a located  in  o u n gth  of  tim e o ns, wastew a preparation d  oxygen) in t 5 , 2012 EEC z a   n  this  d ditive  a rking  u tdoor  e  the  a ter  is   and  t o  the   Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  6  EEC interceptor  that  can  reduce  the  potential  for  generation  of  sulfides. During  times  of  inactive  kitchen  operations, when  wastewater  discharge  to  the  interceptor  is  reduced  or  stopped, the  additional  oxygen  is  discontinued  and  the  potential  for  sulfide  generation  can  be  increased.   To  characterize  interceptor  wastewater  during  active  and  inactive  kitchen/wastewater  discharge  activities, sampling  events  were  scheduled  and  conducted  on  varying  days  of  the  week  and  varying  times  of  the  day  over  the  course  of  several  months  and  seasons  (Table  4 ‐1, EEC  Field  Visits  to  Date ). The  field  visits  consisted  of  wastewater  sampling, core  sampling  and  visual  observations  of  each  GGI.  Table 4 ‐1, EEC Field Visits to Date Date   Day  of  Week  Action  Time  of  Day  Ambient  Temperature (°F) 2/21/2012  Tuesday  GGI  Sampling  Event  Morning  47–65  2/27/2012  Monday  GGI  Sampling  Event  Evening  55  3/8/2012  Thursday  GGI  Sampling  Event  Morning  65–72  3/20/2012  Tuesday  GGI  Sampling  Event  Evening  54–55  4/5/2012  Thursday  GGI  Sampling  Event  Morning  54–56  5/31/2012  Thursday  GGI  Sampling  Event  Morning  63–66  6/8/2012  Friday  GGI  Sampling  Event  Morning  63–67  6/27/2012  Wednesday  GGI  Sampling  Event  Evening  73  6/29/2012  Friday  GGI  Sampling  Event  Morning  64–70  7/10/2012  Tuesday  GGI  Sampling  Event  Evening  70–71  Key:  °F  = degrees  Fahrenheit  GGI  = gravity  grease  interceptor   4.1 Wastewater Sampling and Visual Observations  Sample  collection  and  field  analysis  was  performed  for  wastewater  from  each  grease  interceptor. All  attempts  were  made  to  collect  samples  representative  of  the  effluent  discharge  from  each  interceptor. With  the  exception  of  the  Claim  Jumper  interceptor, all  of  the  interceptors  in  the  study  included  a  sample  box, which  enabled  retrieval  of  representative  grab  samples. Because  there  is  not  a  sample  box, the  samples  from  the  Claim  Jumper  interceptor  were  collected  from  the  second  chamber  (from  below  the  floating  FOG  layer), as  close  to  the  interceptor  outlet  flow  as  possible  (Figure  4 ‐1, Sample  Point  Locations  within  Gravity  Grease  Interceptors ).   Grease  Inte W1425.010  F I  Field  ana conducte d  4.1.1 A  A  four ‐ga H 2 S  level  i 4.1.2 D  A  visual  c in  each  w Colorime t rceptor  Sulfide  M Costa  Mesa  Sa n F igure 4 ‐1 ,I nterceptor lysis  was  pe r d  within  5  mi A irborne Hy d s  photoioniz a i nside  each  g D issolved Su lf olorimetric  f i w astewater  s t ric  Field  Tes t e Fig u M itigation  Stud y n itary  District  , Sample P o s with Sam p r formed  usi n nutes  of  sam d rogen Sulfi a tion  detect o rease  interce lf ide i eld  test  (CH E s ample  colle c er ). u re 4 ‐2, CH y  at  South  Coast  o int Locati o p le Box n g  common  e ple  collectio n de Gas o r  field  mete r ptor  prior  to E Metrics  R ‐9 5 c ted  from  th EMetrics R Plaza 7 o ns within Clai m e nvironment a n . r  (MultiRAE  P fully  openin g 5 10) was  use d e  grease  int R ‐9510 Col o Gravity G r m Jumper G r a l  field  equi p P lus) was  util i g  for  sample  c d  to  determi n erceptors  (F i o rimetric F r ease Inter r avity Grea s p ment, with  ized  to  dete r c ollection.  n e  the  level  o i gure  4 ‐2, C H F ield Tes t e r  November  5 ceptors s e Intercep t all  measure m r mine  the  air b o f  dissolved  s H EMetricts  R r 5 , 2012 EEC t or m ents  b orne  s ulfide  ‐9510   Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  8  EEC 4.1.3 Temperature/pH  A  field  temperature  meter  (HANNA  HL  1288) was  used  to  measure  temperature  and  pH  of  each  sample  of  grease  interceptor  wastewater. The  effluent  sampling  locations  in  the  GGI  are  shown  in  Figure  4 ‐1.  4.2 Maintenance Condition Assessment In  addition  to  effluent  from  the  interceptor, the  maintenance  condition  of  each  interceptor  was  also  evaluated  due  to  its  potential  to  contribute  to  the  generation  of  sulfides. Excessive  loading  of  FOG  and  solids  within  a  grease  interceptor  provides  increased  opportunity  for  the  decay  of  organic  material, which  generates  sulfides. The  maintenance  condition  of  each  subject  grease  interceptor  was  tested  using  a  wastewater  core  sampler  (Dip  Stick  Pro  by  Environmental  Bio  Solutions, Inc, Figure  4 ‐3) to  measure  the  level  of  floating  FOG  and  settled  solids  within  the  first  and  second  chambers  of  the  interceptor.). A  grease  interceptor  is  generally  considered  to  be  in  proper  maintenance  condition  when  the  combined  level  of  floating  FOG  and  settled  solids  does  not  exceed  25% of  the  interceptor  depth; this  is  known  as  the  25% rule. When  the  combined  level  of  floating  FOG  and  settled  solids  exceeds  25% of  the  interceptor  depth, the  interceptor  is  considered  to  be  in  need  of  maintenance  (called  pump ‐out).  Figure 4 ‐3, Wastewater Core Sampler   Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  9  EEC 5.0 FINDINGS/RESULTS 5.1 Boudin SF  Based  on  historical  pumping  records, the  1,500 ‐gallon  grease  interceptor  serving  the  Boudin  SF  facility  is  pumped  out  approximately  once  every  six  months. Based  on  core  sampling  observations, the  kitchen  wastewater  from  this  facility  contains  more  solids  than  FOG; however, the  settled  solids  within  the  interceptor  are  loose  and  easily  mixed  (by  normal  wastewater  flows  and/or  sampling  activities), resulting  in  inconsistent  measurements  of  settled  solids. No  use  of  an  odor/sulfide ‐reducing  chemical  additive  was  reported  for  this  interceptor  and  no  additives  were  evaluated  in  this  location  during  this  study.  Historically, dissolved  H 2 S  levels  in  the  Boudin  SF  interceptor  have  been  observed  in  the  range  of  7  to  10  milligrams  per  liter  (mg/L) (from  2011  District  sampling  activities). Sampling  during  this  study  also  showed  a  consistently  high  level  of  dissolved  H 2 S  (4.7  mg/L  average; Table  5 ‐1, Boudin  SF  Gravity  Grease  Interceptor  Results ). In  addition, high  levels  of  airborne  H 2 S  were  detected  during  the  majority  of  sampling  events. Sulfide  odors  were  generally  evident  after  opening  the  lids  to  this  interceptor. Routine  inspections  of  the  kitchen  activities  confirmed  no  chemical  additive  usage  or  atypical  kitchen  practices  that  might  contribute  to  elevated  sulfides  in  the  grease  interceptor.  Table 5 ‐1, Boudin SF Gravity Grease Interceptor Sampling Results Date  Time  of  Day  FOG/Solids  (%) pH  Water  Temp. (°F) Dissolved H 2 S  (mg/L) Airborne H 2 S  (mg/L) Last  Pump  Date  Other  2/21/2012  6:50  23  5.5  72.2  6  50  1/3/2012  2/27/2012  21:15  13  5.7  75.5  5  63  1/3/2012  3/8/2012  8:05  22  5.5  79.9  3  11  1/3/2012  3/20/2012  19:10  12  5.5  74.7  3  3  1/3/2012  4/5/2012  7:40  6  5.1  75.3  3  11  1/3/2012  Sludge  observed  in  SB  5/31/2012  7:50  8  6.0  79.3  7  3  1/3/2012  Sludge  observed  in  SB  6/8/2012  8:30  8  6.0  71.7  8  0  1/3/2012  Sludge  observed  in  SB  6/27/2012  20:50  26  5.7  72.9  4  0  1/3/2012  Sludge  observed  in  SB  6/29/2012  7:50  ‐ ‐ ‐ ‐ ‐ 1/3/2012   Obstructed  by  vehicle  7/10/2012  21:15  2  5.9  82.0  3  0  7/3/12  No  issues  Key:  °F  = degrees  Fahrenheit   H 2 S  = hydrogen  sulfide  mg/L  = milligrams  per  liter  SB  = sample  box   The  Boudin  SF  interceptor  is  not  pumped  on  a  regular  basis  and  it  experienced  maintenance  issues, including  a  damaged  baffle  tube  and  a  sludge ‐like  accumulation  in  the  sample  box  (did  not  appear  to  be   Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  10  EEC FOG), during  the  study  period. The  FSE  addressed  all  the  issues  prior  to  the  conclusion  of  the  study  and  committed  to  a  quarterly  pump ‐out  schedule.   Pumping  alone  did  not  appear  to  have  a  substantial  effect  on  reducing  H 2 S  discharged  from  the  Boudin  SF  interceptor. A  measurement  of  3  mg/L  dissolved  H 2 S  was  recorded  on  July  10, 2012, seven  days  after  the  previous  pumping  date. For  comparison, the  average  sulfide  measured  at  this  GGI  was  4.6  mg/L. 5.2 Rainforest Café  Based  on  historical  pumping  records, the  3,750 ‐gallon  interceptor  serving  the  Rainforest  Café  is  pumped  out  approximately  once  every  3  months  (quarterly). Based  on  core  sampling  observations, the  wastewater  from  this  facility  contains  a  similar  level  of  floating  FOG  and  settable  solids. No  odor/sulfide  reducing  chemical  additive  use  was  reported  for  this  interceptor  and  no  additives  were  evaluated  in  this  location  during  the  study.  Historically, dissolved  H 2 S  levels  in  the  Rainforest  Café  interceptor  have  been  observed  as  high  as  6  mg/L  (from  2011  District  sampling  activities). Sampling  during  this  study  also  showed  a  consistently  high  level  of  dissolved  H 2 S  (4.5  mg/L  average; Table  5 ‐2, Rainforest  Cafe  Gravity  Grease  Interceptor  Sampling  Results ). In  addition, high  levels  of  airborne  H 2 S  were  detected  during  the  majority  of  sampling  events. Strong  sulfide  odors  were  generally  evident  immediately  after  opening  the  lids  to  this  interceptor. Routine  inspections  of  the  kitchen  activities  confirmed  no  chemical  additive  usage  or  atypical  kitchen  practices  that  might  contribute  to  elevated  sulfides  in  this  grease  interceptor.  Table 5 ‐2, Rainforest Café  Gravity Grease Interceptor Sampling Results Date  Time  FOG/ Solids  (%) pH  Water  Temp. (°F) Dissolved  H 2 S  (mg/L) Airborne  H 2 S  (mg/L) Last  Pump  Date  Other  2/21/2012  7:20  22% 4.9  81.3  7  10  12/24/2011  2/27/2012  20:25  17% 5. 6  80.5  2  33  12/24/2011  3/8/2012  8:20  16% 5.1  86.9  6  0  12/24/2011  3/20/2012  19:30  19% 5.3  80  4  14  12/24/2011  4/5/2012  8:00  2% 5.6  82.4  2  0  3/26/2012  5/31/2012  8:05  7% 6.3  80  5  24  3/26/12  6/8/2012  8:15  5% 6.1  81.7  4  24  3/26/12  6/27/2012  21:35  ‐ ‐ ‐ ‐ ‐ 6/25/12  Obstructed  by  vehicle  6/29/2012  7:40  2% 5.6  83.1  6  1  6/25/12  7/10/2012  21:00  16% 6.0  85.5  5  14  6/25/12  Key:  °F  = degrees  Fahrenheit   H 2 S  = hydrogen  sulfide  mg/L  = milligrams  per  liter   This  interceptor  is  pumped  out  on  a  quarterly  basis, which  appears  to  be  effective  in  maintaining  compliance  with  the  25% rule. Pumping  alone  did  not  appear  to  have  a  substantial  effect  on  reducing   H 2 S  discharged  from  this  interceptor. A  measurement  of  6  mg/L  dissolved   H 2 S  was  recorded  on  June  29,  Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  11  EEC 12, four  days  after  the  previous  pumping  date. For  comparison, the  average  sulfide  measured  at  this  interceptor  was  4.5  mg/L.  5.3 Corner Bakery  Based  on  historical  pumping  records, the  1,500 ‐gallon  grease  interceptor  serving  the  Corner  Bakery  facility  is  pumped  once  every  2  to  3  months. Based  on  core  sampling  observations, the  kitchen  wastewater  from  this  facility  appears  to  contain  more  solids  than  FOG; however, the  settled  solids  within  the  interceptor  are  loose  and  easily  mixed  (by  normal  wastewater  flows  and/or  sampling  activities), resulting  in  inconsistent  settled  solids  measurements.  Historically, dissolved   H 2 S  levels  in  the  Corner  Bakery  interceptor  have  been  observed  as  high  as  10  mg/L  (from  2011  CMSD  sampling  activities). For  periods  during  this  study, a  chemical  additive, BioMagic, was  utilized  in  this  interceptor  to  sulfide  control; however, due  to  coordination  issues  between  the  additive  supplier  and  the  Plaza, application  of  this  additive  was  conducted  only  between  March  1  and  14, 2012, and  again  between  June  15  and  July  10, 2012. For  sampling  conducted  during  the  periods  without  additive  application, dissolved   H 2 S  levels  were  observed  between  2  and  8  mg/L  (3.8  mg/L  average; Table  5 ‐3, Corner  Bakery  Gravity  Grease  Interceptor  Sampling  Results ).  Table 5 ‐3, Corner Bakery Gravity Grease Interceptor Sampling Results Date  Time  FOG/Solids   (%) pH  Water Temp. (°F) Dissolved  H 2 S   (mg/L) Airborne  H 2 S   (mg/L) Last  Pump  Date  Other  2/21/2012  7:40  8  5.2  72.3  8  2  2/13/2012  SB  contained  FF  2/27/2012  20:00  17  5.1  71  3  1  2/13/2012  SB  contained  FF  3/8/2012  8:35  15  5.0  74.3  2  0  2/13/2012  SB  contained  FF  3/20/2012  20:00  4  4.8  67  2  ‐ 2/13/2012  SB  contained  FF  4/5/2012  8:30  8  5.1  72  3  0  2/13/2012  SB  5/31/2012  8:45  6  5.7  74  3  1  4/17/2012  SB, Unclear  separation  6/8/2012  9:30  17  6.4  76.7  4  0  4/17/2012  SB  6/27/2012  21:25  ‐ 5.9  78.1  0  0  4/17/2012  Vehicle  obscuring  all  but  SB  6/29/2012  8:10  24  5.3  75.9  0  0  4/17/2012  7/10/2012  20:30  26  5.8  80  0  0  4/17/2012  Key:  °F  = degrees  Fahrenheit  H 2 S  = hydrogen  sulfide  mg/L  = milligrams  per  liter  SB  = sample  box   During  the  initial  additive  application  period  (March  1  to  14, 2012), approximately  1  gallon  per  day  of  the  BioMagic  product  was  applied  to  the  kitchen  wastewater  through  an  automated  dispensing  system. Only  one  sampling  event  was  conducted  during  this  initial  period; the  dissolved  H 2 S  during  the  sampling  event  was  observed  at  2  mg/L. Upon  re ‐establishment  of  additive  application  (between  June  15  and  July  10,  Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  12  EEC 2010), the  dose  was  increased  to  approximately  1.25  gallons  per  day, resulting  in  H 2 S  levels  of  0  mg/L. During  sampling  events  conducted  without  additive  application, some  low  levels  of  airborne  H 2 S  were  detected; however, noticeable  sulfide  odors  were  not  evident. During  sampling  events  during  additive  use, no  airborne  H 2 S  was  detected  (Table  5 ‐3).    This  interceptor  is  pumped  out  every  2  to  3  months, which  appears  to  be  effective  in  maintaining  compliance  with  the  25% rule; however, some  floating  debris/FOG  was  observed  in  the  sample  box, indicating  potential  pass ‐through  to  the  downstream  sewer  system  (i.e., the  Plaza  lift  station; Figure  5 ‐1, Sample  Box  Containing  FOG  Pass ‐Through ). Pumping  alone  did  not  appear  to  have  a  substantial  effect  on  reducing  H 2 S  discharged  from  the  Corner  Bakery  interceptor. A  measurement  of  8  mg/L  dissolved  H 2 S  was  recorded  on  February  21, 2012, eight  days  after  the  previous  pumping  date  (Table  5 ‐3).   Figure 5 ‐1, Corner Bakery Sample Box  5.4 Marche Moderne  Based  on  historical  pumping  records, the  1,500 ‐gallon  grease  interceptor  serving  the  Marche  Moderne  facility  is  pumped  once  every  3  months. Based  on  interceptor  core  sampling  observations, the  wastewater  from  this  facility  contains  similar  levels  of  floating  FOG  and  settable  solids.  Historically, dissolved  H 2 S  levels  in  the  Marche  Moderne  interceptor  have  been  observed  between  3  and  7  mg/L  (from  2011  District  sampling  activities). For  a  period  of  this  study, a  chemical  additive, Enviroklean, was  utilized  in  this  interceptor  to  control  sulfides; however, due  to  coordination  issues  between  the  additive  supplier  and  the  Plaza, application  of  this  additive  was  only  conducted  between  June  6  and  July, 10, 2012. For  sampling  conducted  prior  to  additive  application, dissolved  H 2 S  levels  were  observed  between  2  and  6  mg/L  (3.5  mg/L  average; Table  5 ‐4, Marche  Moderne  Gravity  Grease  Interceptor  Sampling  Results ).   Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  13  EEC Table 5 ‐4, Marche Moderne Gravity Grease Interceptor Sampling Results  Date  Time  FOG/Solids  (%) pH  Water  Temp. (°F) Dissolved  H 2 S   (mg/L) Airborne  H 2 S   (mg/L) Last  Pump  Date  Other  2/21/2012  7:55  7  3.9  74  6  99  1/30/2012  2/27/2012  20:12  22  4.3  76  2  24  1/30/2012  3/8/2012  8:55  24  4.6  81.7  5  21  1/30/2012  3/20/2012  19:45  40  4.4  75.6  2  ‐ 1/30/2012  SB  water  was  pink  4/5/2012  8:15  39  5.0  80.5  4  6  1/30/2012  5/31/2012  8:20  20  5.7  82.2  2  17  4/24/2012  6/8/2012  9:15  33  5.7  84  1  0  4/24/2012  6/27/2012  21:50  39  5.1  82.7  0  0  4/24/2012  6/29/2012  8:40  37  ‐ ‐ 0  5  4/24/2012  Temperature  meter  malfunctioned  7/10/2012  20:15  46  5.3  88.4  0  0  4/24/2012  Key:  °F  = degrees  Fahrenheit  H 2 S  = hydrogen  sulfide  mg/L  = milligrams  per  liter  SB  = sample  box   During  the  additive  application  period  (June  6  to  July  10, 2012), a  dose  of  approximately  1.25  liters  of  the  Enviroklean  product  was  applied  per  day  to  the  kitchen  wastewater  through  an  automated  dispensing  system, resulting  in  H 2 S  levels  of  0  mg/L.  During  sampling  events  without  additive  use, elevated  levels  of  airborne  H 2 S  were  detected  and  sulfide  odors  were  evident  immediately  after  opening  the  lids  to  this  interceptor. For  sampling  events  conducted  during  additive  use, reduced  airborne  H 2 S  levels  were  measured  and  no  sulfide  odors  were  observed.    This  interceptor  is  pumped  out  every  3  months, which  appears  to  be  ineffective  in  maintaining  compliance  with  the  25% rule; however, no  evidence  of  pass ‐through  was  observed  in  the  sample  box. Pumping  alone  did  not  appear  to  have  a  substantial  effect  on  reducing  H 2 S  discharged  from  this  interceptor.   5.5 Claim Jumper Based  on  historical  pumping  records, the  3,000 ‐gallon  grease  interceptor  serving  the  Claim  Jumper  facility  is  pumped  once  every  3  months. Based  on  interceptor  core  sampling  observations, the  wastewater  from  this  facility  contains  similar  levels  of  floating  FOG  and  settable  solids. No  odor/sulfide ‐reducing  chemical  additive  use  was  reported  for  this  interceptor  and  no  additives  were  evaluated  in  this  location  during  the  study.     Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  14  EEC The  Claim  Jumper  interceptor  sampling  showed  some  detectable  levels  of  dissolved  H 2 S  throughout  the  study  (0.8  mg/L  average; Table  5 ‐5, Claim  Jumper  Gravity  Grease  Interceptor  Sampling  Results ). In  addition, elevated  levels  of  airborne  H 2 S  were  detected  during  a  couple  of  the  sampling  events. Sulfide  odors  were  not  evident  after  opening  the  lids  to  this  interceptor. Routine  inspections  of  the  kitchen  activities  confirmed  no  chemical  additive  usage  or  atypical  kitchen  practices  that  might  contribute  to  elevated  sulfides  in  the  grease  interceptor.  Table 5 ‐5, Claim Jumper Gravity Grease Interceptor Sampling Results Date  Time   FOG/Solids   (%) pH  Water  Temp. (°F) Dissolved  H 2 S   (mg/L) Airborne  H 2 S   (mg/L) Last  Pump  Date  2/21/2012  8:20  15  3.9  82.2  3  55  12/5/2011  2/27/2012  20:55  20  5.6  87  0  1  12/5/2011  3/8/2012  9:35  24  4.6  94.2  0  1  3/6/2012  3/20/2012  21:35  25  5.2  103  0  ‐ 3/6/2012  4/5/2012  8:45  23  4.8  82  1  0  3/6/2012  5/31/2012  9:15  18  5.2  87  1  19  3/6/2012  6/8/2012  9:35  23  4.9  88.4  1  0  3/6/2012  6/27/2012  20:10  14  4.8  98  1  0  6/12/2012  6/29/2012  10:20  16  5.2  88.1  1  3  6/12/2012  7/10/2012  20:00  21  5.3  95.2  0  0  6/12/2012  Key:  °F  = degrees  Fahrenheit  H 2 S  = hydrogen  sulfide  mg/L  = milligrams  per  liter   This  interceptor  is  pumped  out  every  three  months, which  appears  to  be  effective  in  maintaining  compliance  with  the  25% rule. Pumping  alone  did  not  appear  to  have  a  substantial  effect  on  the  level  of  H 2 S  discharged  from  this  interceptor. The  average  temperature  of  wastewater  in  this  GGI  was  notably  higher  than  at  other  interceptors  in  the  study, which  may  be  an  indication  of  higher  flow  rates  into  this  interceptor.   5.6 Z’Tejas  Based  on  historical  pumping  records, the  750 ‐gallon  grease  interceptor  serving  the  Z’Tejas  facility  is  pumped  once  every  1  to  2  months. Based  on  interceptor  core  sampling  observations, the  wastewater  from  this  facility  contains  similar  levels  of  floating  FOG  and  settable  solids.  A  chemical  additive, Golden  Bio, has  been  utilized  in  this  interceptor  for  sulfide  control  since  early  2011  and  throughout  this  study. During  the  study, the  Golden  Bio  product  was  applied  to  the  kitchen  wastewater  through  an  automated  dispensing  system  (actual  dosing  data  not  made  available  by  the  additive  supplier), resulting  in  dissolved  H 2 S  levels  ranging  from  0  to  2  mg/L  (1.1  mg/L  average; Table  5 ‐6, Z’Tejas  Gravity  Grease  Interceptor  Sampling  Results ). Occasional  low  levels  of  airborne  H 2 S  were  also  detected; however, noticeable  sulfide  odors  were  not  evident  immediately  after  opening  the  grease  interceptor.    Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  15  EEC Table 5 ‐6, Z’Tejas Gravity Grease Interceptor Sampling Results Date  Time  FOG/Solids  (%) pH  Water  Temp. (°F) Dissolved  H 2 S   (mg/L) Airborne  H 2 S   (mg/L) Last  Pump  Date  Other  2/21/2012  8:35  14  4.9  93  1  1  2/14/2012  2/27/2012  21:25  20  4.7  83  0  0  2/14/2012  3/8/2012  9:10  38  4.9  90  0  2  2/14/2012  SB  contained  FF  3/20/2012  21:00  11  5.1  85  0  ‐ 3/13/2012  4/5/2012  9:15  28  5.1  89  2  0  3/13/2012  SB  contained  FF  5/31/2012  9:30  26  5.6  94.5  2  5  5/11/2012  SB  contained  FF  6/8/2012  10:20  16  5.5  85.5  1  0  5/11/2012  SB  contained  FF  6/27/2012  20:25  7  5.3  95  2  0  6/12/2012  SB  contained  FF  6/29/2012  9:30  32  6.0  87.8  2  0  6/12/2012  SB  contained  FF  7/10/2012  21:35  51  5.6  90.2  1  0  6/12/2012  SB  contained  FF  Key:  °F  = degrees  Fahrenheit  H 2 S  = hydrogen  sulfide  mg/L  = milligrams  per  liter  SB  = sample  box   This  interceptor  is  pumped  out  every  1  to  2  months, which  appears  to  be  effective  in  maintaining  compliance  with  the  25% rule; however, some  floating  debris/FOG  was  observed  in  the  sample  box, indicating  potential  pass ‐through  to  the  downstream  sewer  system  (i.e., the  Plaza  lift  station). This  apparent  pass ‐through  was  also  observed  during  an  inspection  conducted  by  the  District  prior  to  application  of  any  additives; therefore, the  apparent  pass ‐through  does  not  appear  to  be  related  to  the  additive  usage. Pumping  alone  did  not  appear  to  have  a  substantial  effect  on  reducing  H 2 S  discharged  from  this  interceptor.  Figure 5 ‐2, Z’Tejas Sample Box   Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  16  EEC 5.7 Capital Grille / Seasons 52  Based  on  historical  pumping  records, the  4,000 ‐gallon  grease  interceptor  serving  the  Capital  Grille  and  Seasons  52  facilities  is  pumped  once  every  2  to  3  months. Based  on  interceptor  core  sampling  observations, the  wastewater  from  this  facility  contains  similar  levels  of  floating  FOG  and  settable  solids.  A  chemical  additive, Golden  Bio, has  been  utilized  in  this  interceptor  for  sulfide  control  since  early  2011  and  was  continued  throughout  this  study. During  the  study, the  Golden  Bio  product  was  applied  to  the  kitchen  wastewater  through  an  automated  dispensing  system  (actual  dosing  data  not  made  available  by  the  additive  supplier), resulting  in  dissolved  H 2 S  levels  ranging  from  0  to  7  mg/L  (1.9  mg/L  average; Table  5 ‐7, Capital  Grille  / Seasons  52  Gravity  Grease  Interceptor  Sampling  Results ). Occasional  low  levels  of  airborne  H 2 S  were  also  detected; however, noticeable  sulfide  odors  were  not  evident  immediately  after  opening  the  grease  interceptor.  Table, 5 ‐7, Capital Grille / Seasons 52 Gravity Grease Interceptor Sampling Results Date  Time  FOG/Solids  (%) pH  Water  Temp. (°F) Dissolved  H 2 S   (mg/L) Airborne  H 2 S   (mg/L) Last  Pump  Date  Other  2/21/2012  8:50  14  5.6  83.9  0  0  1/19/2012  2/27/2012  21:35  18  5.7  88.5  2  14  1/19/2012  3/8/2012  9:20  21  5.3  92.7  0  0  1/19/2012  SB  contained  SS  3/20/2012  21:15  23  4.9  90  1  ‐ 1/19/2012  SB  contained  SS  4/5/2012  9:00  11  5.8  88  5  3  3/27/2012  5/31/2012  9:45  18  5.7  95.2  2  2  3/27/2012  6/8/2012  10:00  18  5.7  90  0  0  3/27/2012  6/27/2012  20:35  0  ‐ ‐ ‐ 0  6/27/2012  Just  pumped, not  full  6/29/2012  10:00  5  5.7  94.3  0  0  6/27/2012  7/10/2012  21:45  14  6.0  93  7  8  6/27/2012  Key:  °F  = degrees  Fahrenheit  H 2 S  = hydrogen  sulfide  mg/L  = milligrams  per  liter  SB  = sample  box   This  interceptor  is  pumped  out  every  2  to  3  months, which  appears  to  be  effective  in  maintaining  compliance  with  the  25% rule. Pumping  alone  did  not  appear  to  have  a  substantial  effect  on  reducing  H 2 S  discharged  from  this  interceptor.  Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  17  EEC 5.8 Summary Following  is  a  summary  of  the  key  findings  and  results  from  the  grease  interceptor  sampling  activities:   Left  untreated, the  wastewater  discharge  from  the  Boudin  SF, Rainforest  Café, Corner  Bakery, and  Capital  Grille  / Seasons  52  grease  interceptors  will  continue  to  be  a  source  of  sulfide ‐related  issues  (odors, corrosion, etc.) in  downstream  sewer  lines  and  structures, including  the  Plaza  lift  station.    The  Claim  Jumper  grease  interceptor  did  not  appear  to  be  a  significant  source  of  dissolved  H 2 S  throughout  this  study. While  not  confirmed, the  reason  for  the  low  sulfides  in  the  Claim  Jumper  interceptor  is  likely  due  to  an  apparent  high  flow  rate  of  kitchen  wastewater; the  increased  flow  rate  reduces  the  wastewater  retention  times  within  the  interceptor. However, this  interceptor  could  become  a  source  of  H 2 S  in  the  future  if  operations  change  significantly.   The  Golden  Bio  product  effectively  maintained  dissolved  sulfide  levels  below  2  mg/L  in  the  Z’Tejas  interceptor  during  this  study; however, H 2 S  levels  were  not  consistently  reduced  to  below  the  District  limit  0.5  mg/L. Costs  for  this  product  in  this  particular  application  range  from  $300  to  $325  per  month.   The  Golden  Bio  product  was  less  effective  in  consistently  maintaining  low  dissolved  sulfide  levels  in  the  larger  Capital  Grille  / Seasons  52  interceptor  during  this  study. During  half  of  the  sampling  events, H 2 S  levels  were  reduced  to  below  the  District  limit  of  0.5  mg/L. However, for  the  other  half  of  inspection  events, the  sulfides  ranged  from  2  to  7  mg/L. Costs  for  this  product  in  this  particular  application  range  from  $600  to  $675  per  month.   After  a  dosage  increase  to  1.25  gallons  per  day  in  the  Corner  Bakery  interceptor, the  BioMagic  product  appeared  to  effectively  reduce  dissolved  H 2 S  levels  to  below  the  District  limit  of  0.5  mg/L. However, this  finding  is  based  on  only  three  sampling  events  due  to  the  limited  application  of  the  additive  during  this  study. Costs  for  the  BioMagic  product  in  this  particular  application  range  from  $265  to  $312  per  month.   The  Enviroklean  product  applied  the  Marche  Moderne  interceptor  appeared  to  effectively  reduce  dissolved  H 2 S  levels  to  below  the  District  limit  of  0.5  mg/L. However, this  finding  is  based  on  only  three  sampling  events  due  to  the  limited  application  of  the  additive  during  this  study. Costs  for  this  product  in  this  particular  application  range  from  $300  to  $325  per  month.   Chemical  additives  were  effective  in  the  smaller  grease  interceptors  (1,500  gallons  or  less) but  were  inconsistently  effective  in  the  larger  interceptor. This  inconsistency  is  potentially  due  to  poor  mixing  or  distribution  of  the  additive  throughout  the  large  interceptor, particularly  during  periods  of  low  flow  (e.g., when  restaurants  are  closed).   Left  untreated, the  wastewater  discharge  from  the  Marche  Moderne  grease  interceptor  will  continue  to  be  a  source  of  sulfide ‐related  issues  (odors, corrosion, etc.) in  downstream  sewer  lines  and  structures.     Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  18  EEC  Reducing  dissolved  sulfides  in  the  wastewater  provides  a  corresponding  reduction  in  airborne  H 2 S  levels  and  associated  nuisance  odors.   While  several  early ‐morning  sampling  events  exhibited  airborne  H 2 S  levels  above  10  ppm  (following  long  periods  of  low  wastewater  flow), an  equal  number  of  evening  sampling  events  also  resulted  in  airborne  H 2 S  levels  above  10  ppm.    Elevated  sulfide  levels  were  frequently  observed  shortly  after  (within  days) interceptor  pump ‐out, indicating  that  increased  pumping  frequency  is  not  likely  an  effective  option  for  sulfide  control.  6.0 RECOMMENDATIONS  Based  on  the  findings  and  results  of  the  study, EEC  recommends  the  following  next  steps:   Consider  each  of  the  Golden  Bio, BioMagic, and  Enviroklean  products  as  options  for  mitigating  dissolved  sulfide  levels  in  grease  interceptors. The  FSE  (or  responsible  party) should  select  the  product, as  the  FSE  is  ultimately  responsible  for  compliance  with  the  program  requirements.    Develop  a  fact  sheet  to  assist  FSEs  in  discussing/evaluating  additive  alternative  with  the  vendors/suppliers, including  performance  measures  for  vendors  to  meet  and  demonstrate  to  the  FSE.    Review  findings  of  this  study  with  South  Coast  Plaza  management.   Schedule  and  conduct  a  stakeholder  meeting  (group  meeting  or  multiple  individual  meetings) with  the  FSEs  that  have  grease  interceptor  tributaries  to  the  Plaza  lift  station. Conduct  meeting(s) to  provide  outreach  and  education  pertaining  to  the  ongoing  sulfide  issues  identified  in  this  study. Meeting(s) should  include  representatives  from  the  District  and  the  Plaza.  o District  to  provide  additional  information/education  on  the  District’s  FOG  program.  o District  to  provide  information  on  FSE  responsibility  to  meet  dissolved  sulfide  limitations, District  monitoring  activities  (inspections), and  available  enforcement  actions  where  noncompliance  is  identified.  o Plaza  management  staff  to  encourage  implementation  of  corrective  measures  to  ensure  minimal  impacts  to  Plaza  tenants  and  customers.  o Plaza  management  staff  to  share  information  on  their  experiences  with  chemical  additives  and  provide  cost  and  vendor  information  for  products  evaluated  during  this  study.   In  collaboration  with  FSEs, discuss  and  establish  a  reasonable  timeline  for  implementation  of  corrective  measures; follow ‐up  through  implementation.     Grease  Interceptor  Sulfide  Mitigation  Study  at  South  Coast  Plaza  November  5, 2012 W1425.010  Costa  Mesa  Sanitary  District  19  EEC  Engage  vendors  of  chemical  additives  to  develop  alternatives  for  improving  performance  in  larger  grease  interceptors  (multiple  dispensing  location, mixing, etc.).   Upon  implementation  of  corrective  measures, monitor  dissolved  sulfide  levels  in  grease  interceptors  to  ensure  compliance  with  District  regulations.  _____________, 2013 XXX Re: Costa Mesa Sanitary District Discharge Requirements Dear M r . XXX : The Costa Mesa Sanitary District (District) is the owner of the public sewer system serving your business and is responsible for keeping the sewer system functioning properly. In order to protect the sewer system and the District personnel servicing the sy stem , the District has established regulations identifying the specific prohibitions and limitations for the wastewater discharged from each sewer system user . The wastewater flow from your food service establishment sinks, cooking equipment and drains fl ows into a grease interceptor prior to discharging to the sanitary sewer system. Wastewater systems with low flows , such as your grease interceptor, are susceptible to undesirable septic conditions that can lead to generation of hydrogen sulfide (H 2 S ) gases and the associated "rotten egg" odors. Such odors have been historically probl ematic at the South Coast Plaza . Further, when hydrogen sulfide combines with moist warm air it form s into sulfuric acid that deteriorates the concrete and metal surface s in the District’s pumping station located at the plaza. Both the Costa Mesa Sanitary District as the local collection system owner and the Orange County Sanitation District (OCSD) as the regional treatment plant owner have a discharge limit for dissolve d sulfides (H2S) of 0.50 mg/L. When sulfide levels in excess of 0.50 mg/L are detected, the owner/operator of the wastewater system is required to reduce the sulfide level to the allowable discharge limit. Recently, in coordination with South Coast Plaza Management, the District conducted a series of wastewater sampling events at the grease interceptors associated with the District owned wastewater pumping station at the Plaza. This sampling effort identified H 2 S levels in the wastewater discharged from y our grease interceptor to be well above the permitted discharge limit. The District appreciates your efforts to date, which include s routine pumping services for your gre ase interceptor . However, d ue to the corrosion and odor issues associated with H 2 S , the District is req uiring your cooperation in reducing the H 2 S level in the wastewater from your grease interceptor . The District requests immediate implementation of the following preventative measures: o Ensure grease interceptor maintenance includes complete removal (pumping) of all interceptor contents as prescribed in Section 374.5 of the California Penal Code and Division 12.4 of the California Public Resource Code (Assembly Bill No.1333); XXX CMSD Discharge Requirement March 29, 2013 Page 2 of 2 o Request and ensure thorough cleaning of the interceptor wal ls is included in your grease interceptor service agreement and promptly repair any identified structural problems; o Conduct routine cleaning of the private sewer line(s) between the kitchen and the grease interceptor; o Utilize a wastewater H 2 S treatment additive. Each wastewater/grease interceptor system is different and can require varying approaches to reducing sulfide levels. Depending on the specific conditions of your system, some combination of the above measures may be needed to effecti vely and consistently reduce the H 2 S level to the allowable discharge limit of 0.5 mg/L. F ood service establishments identified with elevated H 2 S issues have requested the use of H 2 S treatment additives to help reduce their H 2 S levels. Based on cursory evaluation of several products performed by South Coast Plaza Management and the District, the following H 2 S treatment additives have demonstrated some level of effectiveness in reducing H 2 S levels. While these products are not endorsed by the District , o ut -of -compliance FSEs using these additives, together with enhanced interceptor maintenance practices, have been successful in reducing their H 2 S to complian t levels. Product Name Intended Use Company Contact Name Company Contact Phone Golden Bio (Golden Bell) H 2 S reduction Murrill Adams 714 -630 -3861 www.goldenbellproducts.com BioMagic H 2 S reduction Scott Schlegel 949 -631 -6159 www.biomagic.com EnviroKlean H 2 S reduction Juan Loeza (909) 855 -2765 Other H 2 S treatment additives may be available to reduce H 2 S levels. Use of additives not listed above must be authorized by the District (Wastewater Additive Use Variance Request form) prior to introduction of the additive into the wastewater system. Upon receipt of this letter, please contact our fats, oils, and grease program consultants, either Jim Kolk or Joseph Jenkins of Environment al Enginee ring & Contracting (EEC) at (714) 667 -2300, to discuss how your restaurant may achieve compliance with the discharge limits described above . If you have any questions regarding this issue or would like to discuss the requirements in more detail, please contact me at (949) 645 -8400 or at scarroll@cmsdca.gov at your earliest convenience. Sincerely, Scott Carroll General Manager C: Rob Hamers, District Engineer Environmental Engineering and Contracting South Coast Plaza Management South Coast Plaza Bristol Restaurants Contact List And Grease Interceptors Location s 1. Maggianos Kevin Gilbert mg0081gmom@maggianos.com 2. Rainforsest Café Ergun Uslu scpgm@ldry.com 3. McDonald ’s Lucila Moreno 4. Claim Jumper Anna Church achurch@ldry.com 5. Boudin’s Michelle Nguyen café_04 39@boudinbakery.com 6. Z’Tejas Jeffrey Grasso southcoast@ztejas.com 7. Capital Grille & C hris Szechenyl costamesa@tcgdine.com Season ’s 52 Erin Meadows Emeadows@seasons52.com 8. Charlie Palmer Chris Moran cmoran@charliepalmer.com 9. Anqi Edgar Fernandez edgarf@houseofan.com 10. Corner Bakery Mike Zaldivar cb0231@cornerbakerycafe.com 11. Vie De France Francoise Cuzor Francoise.cuzor@vdfy.com 12. Lawry’s Rose Stone rstone@lawrysonline.com 13. Wolfgang Puck Bistro Chris Dawson Christopher.c.dawson @macys.com 14. Champagne Bakery Sergio Camora scpb@champagnebakery.com Page 2 Contact List 15. Marche Moderne John Steving John.steving @marchemoderne.net 16. Nordstrom Café Robert Evans Robert.evans@nordstrom.com 17. Quat t ro Caffé Dennis Silva info@quattrocaffe.com