Ocean Outfall Rule Compliance. Piloting Alternative Technologies for Recharge of the Floridan Aquifer. June 20, PD-Sw202w

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1 Ocean Outfall Rule Compliance Piloting Alternative Technologies for Recharge of the Floridan Aquifer June 20, 2014 PD-Sw202w 1

2 City of Hollywood SRWWTP was significantly affected by the Ocean Outfall Rule 60 Ocean Outfall 55.5 MGD High Purity Oxygen Plant Permitted outfall discharge for over 40 years Chapter / requires 20.4 MGD new reuse 2

3 Several reuse alternatives were evaluated, but feasible options were limited Large User Spray Irrigation Biscayne Aquifer Recharge High chloride, urban landscape Floridan Aquifer Recharge Stringent nutrient limits 3 Uncertainties

4 Established recharge treatment approach Secondary or Tertiary Effluent Microfiltration Reverse Osmosis AOP Backwash Waste Concentrate Recharge Influent to WTP 4

5 Our unique hydrogeology may facilitate an alternative approach 5 Parameter SRWWTP (mg/l) Floridan (mg/l) Sodium 640 1,100 Chloride 1,400 2,100 TDS 3,500 4,500

6 Revised recharge treatment approach Secondary or Tertiary Effluent Microfiltration Reverse Osmosis AOP Backwash Waste Concentrate Reverse Osmosis WTP Influent to WTP Recharge 6

7 However, regulatory challenges exist for Floridan Aquifer recharge Parameter FDEP Broward County Biochemical Oxygen Demand 20 mg/l 5 mg/l Total Nitrogen 10 mg/l -- Chemical Oxygen Demand mg/l Phosphates (as P) mg/l Sodium Chloride Total Dissolved Solids Subject to background water quality 160 mg/l 250 mg/l 500 mg/l Emerging contaminants?? 7

8 Receiving water defines pollutant Salt Sodium Chloride TDS Nutrients Nitrogen Phosphate PD - Sw202w 8 Emerging contaminants Caffeine Ibuprofen DEET Triclosan Progesterone

9 County regulators approached regarding alternative treatment Waivers for certain parameters may be possible Removal of emerging contaminants demonstrated Compare quality to Best Available Technology however, emerging contaminants are not regulated No Federal standards exist No State standards exist No County standards exist 9

10 Approach to evaluating undefined contaminant removal PD-Sw202w 10

11 We proposed California s Title 22 Groundwater Replenishment Reuse Functional Group Framework Shifts away from 1,4-dioxane and NDMA approach Relies upon a group approach to contaminant removal Similar chemistries similar removal 9 functional groups defined; Requires demonstrated removal of surrogates from 5 of 9 groups Provides framework for the use of surrogates (e.g., UV254) for process monitoring and control Opens the door for non-ro based approach Nutrient Reverse Advanced Reduction Microfiltration Osmosis Oxidation Recharge 11 Secondary Effluent X X

12 Demonstrate >0.5 log (69%) removal of surrogates from A - G Functional Group (A) Hydroxy Aromatic Example Compounds Acetominophen, Bisphenol A, Triclosan (B) Amino/Acylamino Aromatic Atorvastatin, Sulfamethoxazole (C) Nonaromatic C=C (D) Deprotonated Amine (E) Alkoxy Polyaromatic (F) Alkoxy Aromatic (G) Alkyl Aromatic Carbamazepine, Codeine, OTNE Fluoxetine Caffeine, Trimethoprim Naproxen, Propranolol Gemfibrozil, Hydrocodone DEET, Dilantin, Ibuprofen, Primidone 12

13 Demonstrate >0.3 log (50%) removal of surrogates from H or I Functional Group Example Compounds (H) Saturated Aliphatic Iopromide, Meprobamate (I) Nitro Aromatic Atrazine, Musk ketone, Musk xylene PD - Sw202w 13

14 In addition to log removal, Drinking Water Guidelines also used to verify treatment efficacy Compound Functional Group Guideline Value 1,4-Dioxane -- 3 µg/l Atrazine (I) Nitro Aromatic 3,500 ng/l Carbamazepine (C) Nonaromatic w/ carbon double bonds 73.5 ng/l Dilantin (G) Aklyl Aromatic 73.5 ng/l Fluoxetine (D) Deprotonated Amine 3,395 ng/l Gemfibrozil (F) Alkoxy Aromatic 15,050 ng/l Iopromide (H) Saturated Aliphatic 1,750,000 ng/l Naproxen (E) Alkoxy Polyaromatic 45,500 ng/l NDMA ng/l Sulfamethoxazole (B) Amino/Acylamino Aromatic 150,500 ng/l Triclosan (A) Hydroxy Aromatic 105,000 ng/l 14

15 PILOT TESTING & RESULTS PD-Sw202w 15

16 Treatment designed specifically for emerging contaminants - County approval received 16

17 Treatment designed specifically for emerging contaminants - County approval received 17

18 As expected, waivers would be needed for certain parameters Pilot Effluent Averages (mg/l) 18 Parameter Anticipated Limit (mg/l) Scheme 1 (UV-AOP) Scheme 2 (Ozone) BOD TSS TN Nitrite Phosphates COD TOC TOX Chloride 250 1,400 1,400 TDS 500 3,480 3,460

19 Appropriate emerging contaminant oxidation demonstrated for key parameters except NDMA Emerging Contaminant Functional Group Anticipated Drinking Water Guideline Pilot Influent Scheme 1 UV Dose of 400 mj/cm 2 Scheme 2 Ozone Dose of 5-8 mg/l 1,4 Dioxane < 2.0 (2) < 2.0 (2) < 2.0 (2) Atrazine I 3, < 1.3 (2) < 1.6 (2) Carbamazepine C < 10 (2) < 10 (2) Dilantin G < 103 (2) < 103 (2) Fluoxetine D 3, < 26 (2) < 26 (2) Gemfibrozil F 15, < 26 (2) < 26 (2) Iopromide H 1,750,000 < 51 (2) < 51 (2) <115 (2) Naproxen E 45,500 < 51 (2) < 51 (2) < 51 (2) Sulfamethoxazole B 151, < 10 (2) < 16 (2) Triclosan A 105, < 52 (2) < 52 (2) 19 NDMA

20 Process Scheme 1: NDMA formation in BAC 20

21 Process Scheme 2: NDMA Limit Not Met PD - Sw202 w 21

22 Additional Process Scheme 2b tested for NDMA oxidation post BAC filters DBF IX OZONE PD - Sw202w 22 UV BAC

23 Process Scheme 2b: NDMA limit met 23

24 Emerging Contaminant Summary Log Removal Emerging Contaminant Functional Group Log Removal Scheme 1 UV Dose of 400 mj/cm 2 Scheme 2 Ozone Dose of 5-8 mg/l Scheme 2b UV Dose of 1000 mj/cm 2 1,4 Dioxane Not found Not found --- Atrazine I 0.3 >1.1 > Carbamazepine C 0.5 >1.0 > Dilantin G 0.5 >0.1 > Fluoxetine D 0.5 >0.1 > Gemfibrozil F 0.5 >1.7 > Iopromide H 0.3 Not found Not found --- Naproxen E 0.5 Not found > Sulfamethoxazole B Triclosan A 0.5 >0.7 > NDMA N/A N/A >0.7 *N/A = effluent concentrations above influent concentrations **Representative of pilot operation sampling data from Jan to Nov. 2013

25 Emerging contaminant summary Emerging Contaminant Functional Group Log Removal Scheme 1 Scheme 2 1,4 Dioxane Not found Not found Atrazine I 0.3 Yes Yes Carbamazepine C 0.5 Yes Yes Dilantin G 0.5 Yes Yes Fluoxetine D 0.5 Yes Yes Gemfibrozil F 0.5 Yes Yes Iopromide H 0.3 Yes Yes Naproxen E 0.5 Yes Yes Sulfamethoxazole B 0.5 Yes Yes Triclosan A 0.5 Yes Yes NDMA Yes After BAC Stabilization Yes With Process Scheme 2B 25 *Representative of pilot operation sampling data from Jan to Nov. 2013

26 Further discussions with Broward County were undertaken regarding waivers/variances Waiver/Variance pursued for COD, Chloride, TDS, Sodium, Phosphates Waiver/Variance conditions Discharge will not cause pollution or otherwise damage to the natural resources in contravention with regulations Undue hardship must evident Need to evaluate hardship of meeting standards, specifically phosphates limit of 0.01 mg/l Present results at public hearing 26

27 Hardship Evaluation PD-Sw202w 27

28 Treatment levels evaluated Description Effluent Concentration TN Phosphates COD TDS Emerging Contaminant Oxidation TL 1: FDEP Standards DBF, IX for TN, Disinfection < 10 mg/l > 1 mg/l > 10 mg/l > 3,000 mg/l No TL 2: Piloted Schemes DBF, IX for TN and TOC, UV AOP and BAC < 10 mg/l > 1 mg/l > 10 mg/l > 3,000 mg/l Yes TL 3: Phosphate Removal Level 1 5 Stage BNR, Alum, DBF, IX for TOC, < 10 mg/l > 0.1 mg/l > 10 mg/l > 3,000 mg/l Yes Ozone, BAC and UV TL 4: Phosphate Removal Level 2 5 Stage BNR, Alum, High Rate Clarification, DBF, IX for TOC, Ozone, BAC and UV TL 5: Phosphate Removal Level 3 Electrocoagulation and/or IX, High Rate Clarification, IX for TN, UV AOP and BAC TL 6: Broward County Standards MF, RO 28 and UV AOP < 10 mg/l > 0.03 mg/l > 10 mg/l > 3,000 mg/l Yes < 10 mg/l mg/l > 10 mg/l > 3,000 mg/l Yes < 10 mg/l < 0.01 mg/l < 10 mg/l < 500 mg/l Yes

29 Economic hardship may be demonstrated 20-yr Present Worth PD - Sw202w 29

30 Questions? PD-Sw202w 30

31 Side stream SELECTIVE phosphate testing PD-Sw202w 31

32 Process Scheme 1: phosphate results (without selective PO 4 treatment) 32

33 Emerging phosphate removal technology: Ion Exchange (IX) Ion Exchange for Selective Phosphate Removal Anionic Thermax Resin Contains Iron Particles Never been tested Piloted at 6-8 gph Piloted with columns in series 33

34 Selective IX phosphate testing results 3-DAY BREAKTHROUGH TEST PD - Sw202w 34

35 - Emerging phosphate removal technology: Electrocoagulation (EC) Current applied across iron or aluminum plates Destabilizes particles and pollutants Forms coagulant, facilitates settling Removes: Nutrients (phosphates) Organics Color and Hardness Some emerging contaminants 35 Electrocoagula tion Apparatus

36 Electrocoagulation performance Tested Secondary Effluent and IX Effluent from SRWWTP 36 99% Phosphate Removal