1. Arsenic in Private Wells in New Hampshire Assessing and Managing Risks Mark Borsuk, Thayer School of Engineering, Dartmouth College Paul Susca, Drinking Water and Groundwater Bureau, NHDES Nov 12, 2014 NHMA Pierce Rigrod, Supervisor Drinking Water and Groundwater Bureau, NHDES Presentation Credits

2. Outreach (2000 – present) Outreach (2000 – present) Fielding phone calls about well testing, treatment Fielding phone calls about well testing, treatment Private Well Working Group 2007-2009 Private Well Working Group 2007-2009 Legislation 2009-2010 Legislation 2009-2010 Since 2010 Since 2010 Dartmouth Toxic Metals Program Dartmouth Toxic Metals Program NH Pediatric Society NH Pediatric Society NH child care providers (day care) NH child care providers (day care) NH Building Officials Association et. al. – “potable” def. NH Building Officials Association et. al. – “potable” def. DES Private Well Initiative

4. Barriers? Lack of knowledge Lack of knowledge How to test and what to test for How to test and what to test for What to do with the results What to do with the results Complacency Complacency Inconvenience Inconvenience Lack of a perceived problem Lack of a perceived problem “Knowledge and better information by themselves were found to provide a weak basis for changing behavior.” Imgrund, et. al. (2011) “Knowledge and better information by themselves were found to provide a weak basis for changing behavior.” Imgrund, et. al. (2011)

5. CDC Grant – NHDES & DPHS Project Outline (through September 2015) Year 1 Year 1 Surveys on testing, treatment, barriers Surveys on testing, treatment, barriers Estimate exposure & health effects Estimate exposure & health effects Identify Interventions for Year 2 Identify Interventions for Year 2 Begin development of web-based tool for choosing treatment Begin development of web-based tool for choosing treatment Year 2 Year 2 Implement Interventions Implement Interventions Measure impact on testing, etc. (partnering with LANH) Measure impact on testing, etc. (partnering with LANH) Complete web-based interpretation/guidance tool Complete web-based interpretation/guidance tool

6. Technical Team NHDES NHDES Drinking Water and Groundwater Bureau Drinking Water and Groundwater Bureau State Geologist State Geologist Health Risk Assessment Program Health Risk Assessment Program USGS USGS New England Water Science Center New England Water Science Center NHDHHS/DPHS Laboratory Services Environmental Public Health Tracking Program Dartmouth College Superfund Research Program School of Engineering School of Medicine

7. 2014 Behavioral Risk Factor Surveillance System Questions Main source of DW at home Main source of DW at home Last time well tested for arsenic Last time well tested for arsenic Exposure reduction Exposure reduction Tap water consumption/day Tap water consumption/day

8. CDC Grant – NHDES (& DPHS) Project Outline (through September 2015) Year 1 Year 1 Focus group and surveys on testing, treatment, barriers Focus group and surveys on testing, treatment, barriers Estimate exposure & health effects Estimate exposure & health effects Identify Interventions for Year 2 Identify Interventions for Year 2 Begin development of web-based tool for choosing treatment Begin development of web-based tool for choosing treatment Year 2 Year 2 Implement Interventions Implement Interventions Measure impact on testing, etc. (partnering with LANH) Measure impact on testing, etc. (partnering with LANH) Complete web-based interpretation/guidance tool Complete web-based interpretation/guidance tool

9. Survey Populations Well owners – 5,800 addresses Well owners – 5,800 addresses From list of 50,000 From list of 50,000 Stratified based on est. avg. As concentration Stratified based on est. avg. As concentration Recipients of testing flier – 1,471 Recipients of testing flier – 1,471 Water testing customers Water testing customers General public General public Press releases Press releases Postcards, etc. to town officials Postcards, etc. to town officials

10. Survey 10

12. 12 Survey Results: Testing and Treatment Rates Sankey diagram showing the flow of well owners through the multi-stage process of well water testing and treatment. Boxes represent possible states corresponding to various possible survey responses, with the number of well owners in each state (out of a hypothetical 1000 survey respondents) indicated within each box. Flows between states were derived from cross tabulation tables of the corresponding survey responses scaled to represent 1000 total well owners.

13. 13 Testing and Treatment Rates About 40% (310/750) of those from higher risk arsenic towns have not tested their water for arsenic. Almost 40% (165/440) of those from higher risk arsenic towns who are having their water tested for arsenic are receiving test results that are ‘concerning’ to them. Less than 10% (5/80) of those from lower risk arsenic towns who are having their water tested for arsenic are receiving ‘concerning’ test results. Only about half (145/270) of those who treat their water and state that their intent is to remove arsenic actually have treatment systems that are effective at arsenic removal. However, most of those who are correctly treating (90/145) are those who received concerning arsenic test results. Most of those who are incorrectly treating their water are those who have not had their water tested for arsenic.

14. Predicting Arsenic Testing Rate Using CART N = 686 51.7% test rate (355 out of 686) Town high arsenic mean prob > 14% Town high arsenic mean prob < 14% n = 152 Income < $100K/y Income > $100K/y n = 108 20.4% test rate (20 out of 98) 70.0% test rate (7 out of 10) Town high arsenic max prob < 60.5% Town high arsenic max prob > 60.5% n = 534 Did NOT talk to friends or family about water quality Did talk to friends or family about water quality n = 206 Did NOT receive NH DES flyer DID receive NH DES flyer 62.2% test rate (84 out of 135) 81.7% test rate (58 out of 71) n = 314 Multi-family or seasonal home Single-family home 54.8% test rate (166 out of 303) 9.1% test rate (1 out of 11) 7.1% test rate (1 out of 14) n = 328 40.9% test rate (18 out of 44) Non-white White Target Populations: Residents from high arsenic towns (especially non- white residents or those in seasonal or multi-family buildings) who have not talked to friends about water quality Arrow length proportional to amount of variation explained.

15. Survey Conclusions Target populations Target populations High-arsenic towns – promote word-of-mouth High-arsenic towns – promote word-of-mouth Well owners with test results showing high arsenic Well owners with test results showing high arsenic But do not understand what to do, or But do not understand what to do, or Low income Low income Those most likely to be incorrectly treating Those most likely to be incorrectly treating Have not tested, or Have not tested, or Have tested but not consulted water treatment vendor Have tested but not consulted water treatment vendor

17. Health Effects: Data Sources EPA Integrated Risk Information System (IRIS) reports for As use linear dose-response model EPA Integrated Risk Information System (IRIS) reports for As use linear dose-response model Non-melanoma skin cancer: 1998 IRIS report unit risk is 5 per 100,000 people per ppb As Non-melanoma skin cancer: 1998 IRIS report unit risk is 5 per 100,000 people per ppb As Bladder and lung cancer: 2001 National Research Council report unit risk is 3.3 per 10,000 people per ppb As Bladder and lung cancer: 2001 National Research Council report unit risk is 3.3 per 10,000 people per ppb As Estimate based on above “more likely to underestimate health effects” Estimate based on above “more likely to underestimate health effects” (HEALS study in Bangladesh: hazard ratio of 1.34 for all-cause mortality would translate to 272 deaths/yr in N.H.) (HEALS study in Bangladesh: hazard ratio of 1.34 for all-cause mortality would translate to 272 deaths/yr in N.H.)

18. Estimating Health Effects

20. CDC Grant – NHDES (& DPHS) Project Outline (through September 2015) Year 1 Year 1 Surveys on testing, treatment, barriers Surveys on testing, treatment, barriers Estimate exposure & health effects Estimate exposure & health effects Identify Interventions for Year 2 Identify Interventions for Year 2 Begin development of web-based tool for choosing treatment Begin development of web-based tool for choosing treatment Year 2 Year 2 Implement Interventions Implement Interventions Measure impact on testing, etc. (partnering with LANH) Measure impact on testing, etc. (partnering with LANH) Complete web-based interpretation/guidance tool Complete web-based interpretation/guidance tool

24. User Entry for Arsenic≥ 0.25 mg/L? Yes (≥ 0.25 mg/L) a. Point-of-Entry/Whole House Adsorption Treatment b. Strong Oxidation and Filtration Treatment c. Anion Exchange and Neutralizer Treatment No (< 0.25 mg/L) ≥ 0.01 mg/L? No (< 0.01 mg/L) ≥ 0.005 mg/L? Yes (≥ 0.005 mg/L) d. Point-of-Use Adsorption Treatment No (< 0.005 mg/L) e. No Treatment Needed Yes (≥ 0.01 mg/L) Fe ≥ 0.1 mg/L? Yes (Fe ≥ 0.1 mg/L) Mn ≥ 0.1 mg/L? Yes (Mn ≥ 0.1 mg/L) j. Strong Oxidation and Filtration Treatment k. Softener Cation Exchange and Point-of- Use (Reverse Osmosis or Adsorption) Treatment No (Mn < 0.1 mg/L) l. Weak Oxidation and Filtration Treatment m. Softener Cation Exchange and Point-of- Use (Reverse Osmosis or Adsorption) Treatment Null Value for Mn n. Oxidation and Filtration Treatment o. Softener Cation Exchange and Point-of- Use (Reverse Osmosis or Adsorption) Treatment No (Fe < 0.1 mg/L) f. Point-of-Use Adsorption Treatment g. Point-of-Use Reverse Osmosis Treatment Null Value for Fe h. Point-of-Use Adsorption Treatment i. Point-of-Use Reverse Osmosis Treatment Figure 1 Arsenic Treatment Flow Chart 3 Health messages and treatment guidance will be provided by NHDES for inclusion in final guidance output pages. NH DES – Contract 2014-142, Web Development Services for Constructing A Private Well Water Quality and Treatment Interpretation Tool 3 Web Health & Water Treatment Messages 1 Numeric values in flow charts will be adjusted in accordance with the units specified by the user. Default units of measure for arsenic will be mg/L. 1 Numeric Value Entry and Default Unit 2 Pop-up Message 2 A Pop-Up message will appear on the screen, posing a question to the user, and the answer will be incorporated into the logic. >= 25 ppb? Yes >= 10 ppb? >= 5 ppb? Fe>=100 ppb? Mn>=100ppb?

25. Project Status Public Health Contractor selected: Dec 2013 Focus groups, survey design Conduct surveys, begin health risk estimate: June 2014 TAC review, revision by Dartmouth, final report: Sept 2014 Determine Year 2 interventions: October 2014 Implement interventions: November 2014 – September 2015 Web Tool Contract approved: July 2014 Working prototype: October 2014 Delivery – rollout: Dec 2014 Determine Year 2 enhancements: early 2015 Complete enhancements: Aug 2015