pfoa and pfos occurrence in the santa ana river watershed · 1/8/2019 · • results from wwtp...
TRANSCRIPT
PFOA and PFOS Occurrencein the Santa Ana River Watershed
OCWD Presentation toSAWPA EC Task Force
January 8, 2019
Outline• PFOA & PFOS background
• EPA and CA DDW standards
• OCWD UCMR3 Drinking Water Well Monitoring
• OCWD Watershed Monitoring – SAR, Tributaries, & WWTP
• Current & Future PFOA & PFOS regulations
• Analytical Methods & Recommendations for Monitoring
What are PFOA and PFOS ?• Per- and polyfluoroalkyl substances (PFAS) or alkyl acids (PFAAs)
– PFOA = Perfluorooctanoic Acid (C8HF15O2)– PFOS = Perfluoroctane Sulfonate (C8HF17O3S)
• Key ingredients/byproducts in the production of:– Consumer Products: Teflon, Scotchgard, Stainmaster, Gore-Tex– Polymers for aircraft and electronics– Paper packaging and wrappers for food (e.g., microwave popcorn bags)– Fire fighting foams
• Initially developed in 1940s• PFOA & PFOS phase out in USA in 2000s, replaced w/ shorter chains
PFOA & PFOS Properties• Very stable, resistant to degradation• Resistant to water, grease, and stains (lipophobic)
• Newer & more sensitive laboratory technology has revealed widespread occurrence in environment
• Found in groundwater near manufacturing sites and military bases
EPA/CDC/NIH: PFOA & PFOS health effects• Human epidemiological studies have indicated
– Increased cholesterol levels, thyroid disease risk, high blood pressure, pre-eclampsia– Decreased response to vaccines, fertility in women, infant birthweight (small)
• High-dose lab animal studies have indicated– Damage to liver and immune system– Birth defects, delayed development, newborn deaths– Possible human carcinogenicity for liver, pancreas, thyroid
• CDC ATSDR Toxicology Profile (June 2018 draft)• NIEHS/NIH NTP study was expected in Nov 2018
Initial OCWD PFOS & PFOS TestingWas in OC Drinking Water (2013-2015)
• Unregulated Contaminant Monitoring Rule (UCMR) 3 program• OCWD laboratory developed analytical testing capability (EPA Method 537)• EPA-required reportable detection limits (RDL) :
– PFOA = 20 ng/L – PFOS = 40 ng/L
• UCMR3 results summary– 135 drinking water sites tested (e.g., wells, reservoirs, blending points)– 5 of 19 retailers had detections related to drinking water wells– Three retailers had one or more results > 70 ng/L 2016 EPA Health Advisory– Retailer detections generally downgradient of OCWD SAR recharge area
2016 EPA Health Advisory• Health Advisories are:
– non-enforceable drinking water levels – intended to provide technical guidance to state regulators, public health
officials, and water utilities
• Health Advisory = 70 ng/L (parts per trillion) for PFOA + PFOS
• EPA recommendations for utilities with PFOA + PFOS > 70 ng/L– Confirm testing results and assess sources– Inform consumers– Limit exposure (e.g., via use of alternative sources, blending, treatment)
July 2018: SWRCB DDW Releases InterimDrinking Water Notification Levels & Response Levels• Notification Levels (NL) PFOA = 14 ng/L; PFOS = 13 ng/L
– Advisory in nature and not “enforceable” standards– Utility can continue to serve water if NL exceeded– However, utilities exceeding NL must notify local governing body (e.g., city
council and/or county board of supervisors) – Customer notice is also recommended (e.g., via annual CCR mailing)
• Response Level (RL) PFOA + PFOS = 70 ng/L (same as EPA HA)– If exceeded, DDW recommends source be taken out of service– If utility chooses not to take source out of service, DDW requires significant
additional notification (e.g., press release/conference) and monitoring
Other DDW Notification & Response Level chemicals
Chemical Notification Level Response Level
1,4-Dioxane 1 µg/L 35 µg/L
NDMA 10 ng/L 300 ng/L
TBA 12 µg/L 1200 µg/L
Boron 1 mg/L 10 mg/L
Amended SWRCB Recycled Water Policy (Dec 2018)
• PFOA & PFOS added as “health indicator” CECs for potable reuse projects
• Reporting Limits– PFOA = 7 ng/L– PFOS = 6.5 ng/L
• Monitoring Trigger Levels– PFOA = 14 ng/L– PFOS = 13 ng/L
Other Drinking Water Limits /GuidelinesState PFOA
(ng/L)PFOS(ng/L)
Comments
AZ, AL, CO, ME, MA, MI, NY, RI, WV 70 70 Adopted HAL from 2016
California 14 13 Interim Notification Levels
ConnecticutAction Level:
Combined Results - PFOA, PFOS, PFHxA, PFHpA, PFNA
Minnesota 35 27 Health Based Guidance
Nevada 667 667 Basic Comparison Levels
New Hampshire 38 70 Proposed MCL's: PFOA+PFOS = 70 ng/LPFHxS = 85 ng/L PFNA = 23 ng/L
New Jersey 14 13 PFNA = 13 ng/L
North Carolina NA NA Health Goal for GenX = 140 ng/L
VermontHealth Advisory:
Combined Results - PFOA, PFOS, PFHxS, PFHpA, PFNA
CDC ATSDR 11 7Minimum Risk Levels
PFHxS = 74 ng/L PFNA = 11 ng/L
US EPAHealth Advisory Level
(PFOA & PFOS Combined)70
20
70
OCWD Actions since 2016 EPA HA• Improved lab method (EPA Method 537)
– Reduced RDL to 4 ng/L for PFOA & PFOS (Aug 2016)– Expanded target list from 6 to 15 PFAS compounds (Spring/Summer 2018)
• Expanded testing to identify sources to OC Groundwater– OCWD groundwater monitoring wells (incl. North Basin & South Basin areas)– Groundwater near former El Toro Marine Corps Air Station (MCAS)– Retailer drinking water well testing and coordination as requested– GWRS recharge/injection & MWD OC-28 raw imported water recharge– Santa Ana River (Main river, stormwater, WWTPs/POTWs, tributaries)
• Affected retailers operated systems to avoid serving water > 70 ng/L EPA HA
GWRS & MWD OC-28 Results• OCWD Grounwater Replenishment System (GWRS)
– OCSD Secondary Effluent Source Water = 25 – 38 ng/L PFOA + PFOS– GWRS Final Product = All results non-detect for PFOA & PFOS – Reverse Osmosis is known to be excellent treatment barrier– PFAS testing has been included in quarterly final product monitoring program
• MWD OC-28 imported recharge water results ND for PFOA & PFOS
SAR Imperial Highway sample location represents “headworks” of OCWD SAR recharge system
Santa Ana River at Imperial Hwy
Aug 2016 – Present
Averages (ng/L)PFOA: 21PFOS: 17
PFOA+PFOS: 38
Min / Max (ng/L)PFOA: 10 / 40 PFOS: 10 / 28
PFOA+PFOS: 21 / 59
Cooperative SAR Discharger Testing• 5 different SAR POTW effluent discharges tested
– IEUA: CCWRF, RP1/RP4, RP5
– WMWD: WRCRWA Plant
– SBMWD: RIX
• 2 coordinated events at all 5 POTW sites (05/10/17 & 02/21/18)• Arranged sample collection with POTW staff (Management/Operations)
• Results from WWTP samples have been provided to POTW contacts
• SARDA Presentation of OCWD PFAS results on 10/11/18
WRCWRAPFOA: 24PFOS: 23
SAR Below Prado Dam PFOA: 22PFOS: 16(n = 19)
Chino Creek @ PinePFOA: 17PFOS: 10
IEUA CCWRFPFOA: 25PFOS: 2
IEUA RP1PFOA: 6
PFOS: ND
Upper SAR Watershed Monitoring
Surface Water Site (SAR or Creek)
POTW Facility Effluent to SAR(Sites with n=2 / Site with n=8)
PFOA & PFOS Results (ng/L)Average Reported for sites with multiple samples
IEUA RP5PFOA: 24PFOS: 2
SBVMWD RIXPFOA: 13PFOS: 15
SAR Above RIXPFOA: 10PFOS: ND
SAR @ MissionPFOA: 15PFOS: 14
HV InfluentPFOA: 18PFOS: 7
Temescal Creek at LincolnPFOA: 41PFOS: 29
SAR @ RiverRdPFOA: 16PFOS: 11
Mill Creek @ Chino Corona Rd
PFOA: 9PFOS: 10
SAR @ Van BurenPFOA: 11PFOS: 15
Occurrence of PFAS compounds in wastewaterhas been studied extensively in literature
Occurrence of PFOA & PFOS in conventionally-treated wastewater is well-established
Temescal Creek Sites
• Ephemeral Flows• Temescal Pond: Low WL• Sample Date Range:
Feb. 2017 – Dec 2018
3M Facility Roofing Material
Temescal Creek Sites - Results
3M Facility
Temescal Creekat Auburndale
PFOA: 43PFOS: 26
PFOA+PFOS: 69n=3
Temescal Creek at 91 Fwy(Upstream of Riv. Canal)
PFOA: 51 PFOS: 25
PFOA+PFOS: 76n=2
Temescal PondPFOA: 613PFOS: 219
PFOA+PFOS: 832n=2
Flood Control (at Sherbon)PFOA: 31PFOS: 25
PFOA+PFOA: 56n=2
PFOA & PFOS Results (ng/L)Average Reported for sites with multiple samples
Riv. Canal Before Temescal Creek
PFOA: 35PFOS: 50
PFOA+PFOS: 85n=2
Temescal Creekat LincolnPFOA: 41PFOS: 31
PFOA+PFOS: 72n=5
SUMMARY – OCWD PFAS Monitoring• 3-5 Affected OC Retailers based on 2013-2015 UCMR3 results
• Notification Level testing could reveal additionally affected systems
• GW monitoring to date has not revealed OC industrial point sources
• GWRS and current MWD OC-28 recharge not a source
• Consistent detections > NL in Santa Ana River– Main river– Multiple WWTPs (POTW) discharges– Tributaries (e.g, Temescal Creek, Chino Creek)
Managing PFOA & PFOS in SAR• Groundwater Recharge (GWR) is a designated beneficial use for SAR
• SAR replenishes groundwater in not only OC, but also via losing reaches upstream
• How do Notification Levels inform response to PFOA & PFOS in WWTP discharges?
• Groundwater Recharge Reuse Project (GRRP) Regulations – Require quarterly monitoring for Notification Level compounds– If results > NL for 4-16 weeks, must notify DDW & RWQCB
• PFOA & PFOS included as health-based CECs in new SWRCB Recycled Water Policy
• OEHHA could modify “interim” DDW NL • SWRCB to ask OEHHA to develop PHG required for California MCL• EPA to declare PFOA & PFOS as CERCLA hazardous waste• EPA MCL?• Longer term
– how to handle the other 4000-6000 PFAS compounds (including the “safer” replacements)
– China continues to manufacture PFOA & PFOS
Potential Regulatory Actions
PFAS Laboratory Analysis• EPA Method 537 Rev 1.1 (Drinking Water method released Nov 2018)
– Uses LC-MS/MS instrument similar to other CEC methods – Includes 18 PFAS analytes– Requires Field Reagent Blank (FRB) for additional QA/QC – OCWD RDL = 4 ng/L, successfully applied to treated WW and surface water matrices– Recycled Water Policy required RDLs PFOA=7 ng/L, PFOS=6.5 ng/L
• Some labs have “Modified” EPA 537– Expanded target list– Different sorbent, such as a copolymer ion exchange– Not typically sanctioned by EPA
• EPA working on additional PFAS methods for release in 2019– EPA 8237: non-drinking water, direct injection, 24 PFAS compounds– EPA 8238: non-drinking water/POTW influents/biosolids/soils/DoD sites, 24 PFAS + GenX– New drinking water method for shorter chain PFAS outside of 537 scope
Recommendations for EC Task Force Monitoring
• Sites to include– SAR Wastewater Treatment Plant discharges– SAR surface water sites– Temescal Creek Watershed sites– Sites to help identify any non-WWTP sources (e.g., military bases or
manufacturing sites) to runoff/surface water
• Priority: PFAS compounds• Secondarily consider additional EC’s in updated Recycled
Water Policy (e.g., 1,4-dioxane, NDMA, NMOR, etc.)
Question & Discussion