View
0
Download
0
Category
Preview:
Citation preview
Perfluorochemicals (PFCs) in the East Metro
James Kelly & Karla Peterson
MDH Environmental Health Division
August 21‐22, 2018
Agenda
• What are PFCs (also known as PFAS)?
• Where do they come from?
• Why are they important?
• What are MDH’s Health‐Based Values?
• What about PFCs in Minnesota?
• How have PFCs affected drinking water supplies and what actions have been taken?
• What are future options for community water supplies?
2
PFCs (also known as PFAS)
• Human‐made chemicals found in everyday items
• Used since 1940s to make products that resist heat, stains, water, oil and grease; production increased rapidly in 1970s
• Many other specialized industrial and commercial uses (operative word: non‐stick)
3
?
PFCs in the Environment
• PFCs are persistent in the environment
• PFCs can be found in
• Food packaged or processed with PFAS‐containing materials or grown in contaminated soil/water
• Commercial household products, including stain‐resistant fabrics, nonstick products, polishes, paints, waxes, and cleaning products
• Workplaces that use PFAS
• Drinking water, typically associated with a specific facility or site
• Living organisms, including fish, animals, and humans
4
PFCs in the Environment
• PFCs do not break down
• C‐F bond strongest covalent bond
• No hydrolysis, photolysis, or biodegradation
• Do not adsorb readily to aquifer materials
• Infiltrate rapidly to the groundwater
• Little or no retardation in aquifers
• Rates affected by PFC chain length and functional group
• Chemical structure similar to fatty acids
• “Proteinphiles” ‐ adsorbed into blood serum of living organisms
• Also controlled by chain length and functional group
5PFOA
oq::_ H H H H H ~ II I I I I I _t";;"\
H-o-c-c - c - c-c- c- c - c 0 ct ~~ ~ ~~ k5
Capryhc c1
Why are PFCs important?
• Most people have been exposed to PFCs because they are in so many products
• PFCs can accumulate and stay in the human body for long periods of time
• There is some evidence that exposure to PFCs at high levels is associated with negative health outcomes
6
MDH Health‐Based Values
7
Health‐Based Value
Most Sensitive Health EffectsExposure ≠ Health Effects
Margin of SafetyFraction from Drinking Water
High‐End Water Intake Rate
MDH Health‐Based Values
• MDH evaluates the combined effects of PFCs: Health Risk Index (HRI)
• Allows us to account for differing levels of toxicity in similar chemicals
• Protective for people who are exposed over their lifetimes
• Protective for fetuses
• Based on animal studies showing slight liver and thyroid effects (adults) and immune system and developmental effects (infants/children)
8
PFOS: 0.027 ppb
PFOA: 0.035 ppb
PFBA: 7.0 ppb
PFBS: 2.0‐3.0 ppb
9
Location of 3M PFC Sites in Washington Co., Minnesota
Minneapolis St. Paul N
00.51 2 3 4 5 ·+· • • ,Miles $
Groundwater Flow
• In the eastern half of the county, groundwater flows to the St. Croix River
• In the western half of the county, groundwater flows to the Mississippi River
• Locally, groundwater flow may be influenced by pumping wells
10
PFAS in Surface Water – Important Transport Pathway
11
Groundwater flowSurface water or stormwater flow
m, DEPARTMENT
OF HEALTH - PFOS greater than 1.35ppb (>50x HBV)
- PFOS 0.271-1.35ppb (10-50x HBV)
PFOS0.136-0.27ppb(5-10x HBV)
PFOS 0.028-0.135ppb (1-5x HBV)
- PFOS 0.021-0.027ppb (75-100% HBV)
- PFOS 0.0 136-0.02ppb (50-75% HBV)
PFOS 0.004-0.0135ppb (<50% HBV)
PFOS not detected
NOTES: Map combines data from all aquifers, actual concentrations in any area may vary; blank spaces indicate no sample data
Phone: 651 -201-4897 or 1-800-657-3908
MOH Health Based Value (HBV) for PFOS
is 0.027 parts per billion (ppb; or 27 parts per
trillion)
Result: Extremely Large “Co‐Mingled” Plumes
• Over 130 sq. mi.
• 4 major aquifers
• 8 municipal systems & >1,800 private wells
• Much larger than predicted by models
• PFBA most widespread
• More PFBA in source areas
• More mobile
• Movement of PFAS affected by several factors
12
m, DEPARTMENT
OF HEALTH
- PFBA exceeds HAL (>70ppb)
- PFBA exceeds HAL (7-70ppb)
PFBA - All Aquifers
PFBA 50-75% HAL (3.5-5.25ppb)
- PFBA 25-50% HAL ( 1.75-3.5ppb)
PFBA 75-100% HAL (5.25-7ppb) - PFBA 10-25% HAL (0.7- 1.75ppb)
Phone: 651-201-4897 or 1-800-657-3908
PFBA <10% HAL(0.007-0 .7ppb)
PFBA not detected
city
PFOS and PFOA Less Widespread
13
• PFOS and PFOA present at high concentrations in source areas
• Groundwater concentrations decrease rapidly with distance from source
• Surface water concentrations
• Different PFAS “signatures” in each site based on chemistry at time of disposal
• Washington Co. landfill & Woodbury Disposal Sites dominated by PFCAs
• Helped to identify transport pathways 0
,, SAINT PAUL
PFOA
Mainly PFBA
2
c:: c( Cl z :::J 0 al
~ z :::J 0 Q
4 Miles
WOODBURY
COTTAGE GROVE
AFTON
DENMARK TWP
Well Sampling Effort & Private Well Drinking Water Advisories
• ~2,500 wells sampled since 2003• Frequent, intensive monitoring of private wells:
• Near source areas
• Areas with high or changing PFAS concentrations
• Areas with complex geology
• Less frequent monitoring of “sentry” private wells:• Distal portions of plumes
• Areas with low and stable PFAS concentrations
• Areas with relatively simple geology
• >800 drinking water advisories issued14
m, DHA UMIHT o, H l ,UTH
Well Advisory and Well Sample Locations A Well advisory issued
• Private drinking water wells sampled
Phone: 651 -201-4897 or 1-800-657-3908
a All other wells (municipal, business, church, schoot, moniloring, and other types of wells)
Community Water Supply Impacts
• Everything in a drinking water system is interdependent and very complex
• Trade‐offs: choice of technology, design, and operations can have unintended consequences
• Communication must include the public, regulators/regulatees, and elected officials
• Water systems do not have the luxury of waiting; people drink water every day
m~ DEPARTMENT 11 OF HEALTH
Health Risk and Regulation
• Health risks are incremental
• Standards are discreet segments
• Public perception varies
High
~ ·x ~ ~ C E 0 O C. u Cl) +,J ...
Q,) V,
a:: 0 u .:t:. >
Cl) u ii: C:
Q) llO ':::,
Low Lead R"sk (concentration, distribution}
High
m il DEPARTMENT OF HEALTH
Regulatory Consistency vs. Scientific Discovery
• Implementation of regulations requires consistency
• Science is always learning new facts
• Need space between the two
• Four‐quarter average concentration used
-+- Regulation -+-Science
m il DEPARTMENT OF HEALTH
Response Actions – East Metro
• Removal & proper disposal of contaminated soil
• Treatment of groundwater
• Treatment of drinking water where Health‐Based Values exceeded
18
City of Oakdale water treatment plant
Residential carbon filters
Parties Involved in Response
19
m il DEPARTMENT OF HEALTH
m il DEPARTMENT OF NATURAL RESOURCES
Washington County I MN 3M ~ A great place o live. or . a d play ... o ay and omorro !
A POLL ~T ON N -.Y
Public
water r".._~•':IIIIIW systems
Oakdale (27,973)
• Has 9 wells; PFAS exceeds MDH health‐based guidance value in 7
• PFAS concentrations highest in the state for community systems; peak of 440 ppt PFOA and 610 ppt PFOS
• Treatment (GAC) installed in 2006 for 2 wells; change carbon annually
• Primarily rely on 2 treated wells and 2 “clean” wells for water supply
• Video: http://bit.ly/2rWs9z5
Mounds View White Bear Beach .) ng Laki'IP.art J-
~ Shoreview 1te Bear Lake ~ew'Bngflt~ Vadn/is M.1htomedi Stil1wam
~~;~~• Hea hu Nortj]S Pa B.1yport
Hudwn
Maplew l t..:,ke Elmo
k e , / I J - ,--J,kilooa"""'\
St Paul t:!:i - ~ """"'I.!!!." -=§M1n,wtJ::' Falls \ vfooctbury
West St Paul ~ :...,-"'1
d Mendota Sotth St rtai1 1 1el Heights ~
•~·1 StPa\lPark
/ ... ln~~r Grove C~ge Grove m E~an HeigQb.
_ .. .JI Q_--=-_ .........
Afton
- MINNESOTA -
m, DEPARTMENT OF HEALTH
Cottage Grove (36,492)
• Has 12 wells; 8 with PFAS exceeding MDH health‐based guidance values
• PFAS concentrations: no PFOS, 66 ppt PFOA
• Impacted when health‐based guidance values lowered
• Installed GAC treatment on 2 wells in 2017
• Have a direct blending point for 7 wells that can manage concentrations
• Temporary watering ban in 2017 after receiving health advisory letter from MDH and prior to treatment
I , I
S.tillw,ner
RoseVille North t Paul Bayport
Map ewood l L.1k:e Elmo
Hi.rd son Oakclale _J
I - ~ ak:t! !arf~ .-.,,.__,,,St"'P~a"'u~I --"""e- ic, ~ ~Minnehr,:: Falls \ w"ooobury
\. West St P.au l /. Aft<;in
Mend.la s.Jth St Pa~I Heights
Cottage Grove
~ f tosperity Meet 1'E're Pride an°
m, DEPARTMENT OF HEALTH
Woodbury (69,245)
• 19 wells; PFAS exceeds MDH health‐based guidance values in 5 wells
• PFAS concentrations• PFBA: 0.1‐0.41 ppb (all wells)• PFHxS: 0.07 ppb (Well 13 only)• PFOA: 0.014‐0.049 ppb (8 wells)• PFOS: 0.023‐0.026 ppb (3 wells)
• Primarily rely on wells that meet MDH health‐based values for water supply. Others are used only seasonally to meet peak demand.
~:i;;: Gfflllake
ijjj
-® ijjj
..... ~ .. -St Paul
@) • @) tStPauT
0
lnvNGr~ Heights
qi; p,.,.,Sp<ongs @
@)
Maplewood -
iji; Woodbury
St Paul Part::
Lake Elmo Part;Reser1e
@ Cottage Grove
"' "'
CD '1§)
® ktGo gle
®
® Oak Part:: Heights
Baypon
North Hudson
@® ""'=
Lakeland
Afton
I -· I I l/
m, DEPARTMENT OF HEALTH
Saint Paul Park (5,519)
• Has 3 wells, with 2 exceeding MDH health‐based guidance values
• PFAS concentrations: no PFOS, 43 ppt PFOA
• Impacted when health‐based guidance values lowered
• Want to install treatment on wells
• Managing pumping so clean well is used the most, and enforcing watering restrictions
. e St Paul
~.111(1I~---.....,,-
urs.a!e Woodbury
Cf1' WHt St P•uj f Mt, dOl.J \°uth St Paul "'"'"" 1t
~• 1 ' , N- l r·~ "
tPaul 3rk
Inver ! rove o ttage Grove ~,ghts
' 1;)
m,
--c ..... ....,
DEPARTMENT OF HEALTH
Lake Elmo (4,878 / 8,069)
• Has 3 wells with 1 exceeding MDH health‐based guidance values
• PFAS concentrations: no PFOS, 46 ppt PFOA
• Impacted when health‐based guidance values lowered
• Many private wells in the city
• Options for new well limited by water quantity issues
!HJ Ull.l'"r.' .. 111.
Mounds t'iew IWh1te Be.Jr Beach
Wl11te Bear Lake
umbra •tghts
field
.,
Vadnls Mahtomedi He1 hts
St Paul ,,,M..,.htr:'Fo11, Woodbury - W~t St P..tul t
Mendota So~h St ul H.,ght>
St Pa I Park
ver_ Grove Cottage Grove j erg/l;h
THE ClTY OF
Stillwater
Afton
~KEELMO
m~ DEPARTMENT 11 OF HEALTH
Biomonitoring Shows Effectiveness of Response
25
35.7
14.9
8.2
24.9
11.26.5
18.5
5.5 5.06.32.1 1.3
0
5
10
15
20
25
30
35
40
45
PFOS PFOA PFHxS
2008 2010 2014 NHANES 2011‐12
PFCs decreased in blood of people drinking treated water (average concentrations still above national averages)
Levels down over time
• • • •
Future Response Options
• Regional interconnect
• New treatment facilities
• New wells
• Water conservation; limit use of contaminated wells
• Adapted blending scheme
• Others?
m il DEPARTMENT OF HEALTH
More Information
• MDH General PFAS Information: http://www.health.state.mn.us/divs/eh/hazardous/topics/pfcs/index.html
• ITRC Factsheets: https://pfas‐1.itrcweb.org
• US EPA information: https://www.epa.gov/pfas
• MDH Health Risk Limits: http://www.health.state.mn.us/divs/eh/risk/guidance/gw/table.html
• MPCA PFC Investigations: https://www.pca.state.mn.us/waste/perfluorochemicals‐pfcs
27
Questions?James Kelly
james.kelly@state.mn.us651‐201‐4910
Karla Petersonkarla.peterson@state.mn.us
651‐201‐4679
28
m~ DEPARTMENT 11 OF HEALTH
Recommended