Updated Health Risk Assessment Guidelines

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Copyright 2015 by ERM Worldw ide Limited and/or its affiliates ( ERM ). All Rights Reserved.

1 Updated Health Risk Assessment Guidelines California OEHHA s Air Toxics Hot Spots Program March 31 st, 2015 Insert then choose Picture select your picture. Right click your picture and Send to back. Copyright 2015 by ERM Worldw ide Limited and/or its affiliates ( ERM ). All Rights Reserved. No part of this w ork may be reproduced or transmitted in any form or by any means, w ithout prior w ritten permission of ERM.

Opening Remarks It s all about the kids - The Children s Environmental Health Protection Act of 1999 requires explicit consideration of infants and children in assessing risks from air toxics.

2 Opening Remarks It s all about the kids - The Children s Environmental Health Protection Act of 1999 requires explicit consideration of infants and children in assessing risks from air toxics. The 2015 OEHHA Guidance Manual updates the previous 2003 version and reflects advances in the field of health risk assessment (HRA) along with explicit consideration of infants and children. Lynn McGuire P.E. Western Division Air 2 Practice Leader ERM is offering this Webinar to describe: Key changes in California s HRA methodology Changes in tools used to conduct HRAs Just how much will my AB2588 HRA results change? How the major California Air Districts are revisiting their programs: AB2588 Hot Spots Program Air Permitting CEQA Project Permitting

3 Panel Experts John Koehler, Sc.D., Program Director Walnut Creek, CA Permitting, Engineer, Public Health Danny Kringel, Technical Director Irvine, CA Southern California Dispersion Modeling Lead Vicki Hoffman, Program Director Walnut Creek, CA Northern California Dispersion Modeling Lead 3

4 Introduction OEHHA Updated Health Risk Assessment Guidelines 1. Background 2. Key Revisions Made to the HRA Guidelines 3. Updates to New Risk Model, HARP 2 4. Local California Air District Implementation 5. Take-Away Points on the Updated HRA Guidelines 6. Concluding Remarks/Questions 4

5 Background and Key Revisions

6 History of OEHHA HRA Guidelines Technical Support Documents (TSDs) 1987 AB2588 Air Toxics Hot Spots Law Adopted 1992 First AB2588 HRA Guidelines by CAPCOA 2003 OEHHA releases comprehensive HRA Guidelines 2008 OEHHA issues Revisions for the Derivation of Noncancer Reference Exposure Levels 2009 OEHHA issues Adjusting Cancer Potency Factors for Early Life Exposures 2012 OEHHA issues Exposure Assessment (Revised exposure models and factors) March 6, 2015 Updated OEHHA HRA Guidelines - Age sensitivity factors - Increased breathing rates relative to 2003 HRA Guidelines - Adjusted algorithms and factors for non-inhalation exposures - Adjustments in calculating noncancer health impacts - HARP 2 Hot Spots Assessment and Reporting Program 6

7 Overview of OEHHA HRA approach Follows standard health risk assessment (HRA) approach originally proposed by the National Academy of Sciences Four steps involved in the risk assessment process are: 1. Hazard identification What are the constituents of concern? (emission inventory) 2. Exposure assessment Model environmental transport from sources to receptors (dispersion modeling) 3. Dose-Response assessment Cancer and non-cancer health benchmarks for toxic air contaminants (TAC) (cancer and non-cancer factors) 4. Risk Characterization (Exposure x Exposure Factors) x (Dose-Response) = Health Risk 7

$(mg/kg-day)] ASF = age sensitivity factor (per age bin) DBR = daily breathing rate [L/(kg-day)] FAH = fraction at home ED = exposure time [years] CFs = conversion factors Source: SJVAPCD Final Staff$

8 Cancer Risk: Inhalation Exposure Pathway Cancer Risk = Cair SF DBR ED/AT ASF FAH CFs Cair = pollutant air concentration (µg/m 3 ) AT = averaging period [years] SF = slope factor [cancer risk per (mg/kg-day)] ASF = age sensitivity factor (per age bin) DBR = daily breathing rate [L/(kg-day)] FAH = fraction at home ED = exposure time [years] CFs = conversion factors Source: SJVAPCD Final Staff Report. Update to District s Risk Management Policy to Address OEHHA s Revised Risk Assessment Guidance Document. March 18, 2015.

Age Sensitivity Factors OEHHA adopted procedures (June 2009) to consider the increased susceptibility of infants and children to carcinogens compared to adults. Source: BAAQMD. January 2010.

9 Age Sensitivity Factors OEHHA adopted procedures (June 2009) to consider the increased susceptibility of infants and children to carcinogens compared to adults. Source: BAAQMD. January Air Toxics NSR Program Health Risk Screening Analysis (HRSA) Guidelines. Other Cancer Risk Age Adjustment Factors 30-year residential exposure - adjustment factor: year child residential exposure - adjustment factor: 4.8 9

10 Increased Breathing Rates Note: 95 th /80 th is proposed as part of the statewide Risk Management Guidance document currently being drafted, and would entail using 95th percentile breathing rate for children and 80th percentile breathing rate for adults. Source: SJVAPCD Final Staff Report. Update to District s Risk Management Policy to Address OEHHA s Revised Risk Assessment Guidance Document. March 18,

Cancer Risk for Non-Inhalation Exposure 11 Chemicals subject to

Multi-Pathway HRAs: Soil Ingestion: Small to an order of magnitude

moderate increase (mother s overall exposure passed to child) Home

evaluated (less common) ERM s analysis of non-inhalation pathway

11 Cancer Risk for Non-Inhalation Exposure 11 Chemicals subject to deposition (metals, PAHs, dioxins) Experience with Existing Multi-Pathway HRAs: Soil Ingestion: Small to an order of magnitude increase Dermal Exposure: Little change Mother s Milk: Small to moderate increase (mother s overall exposure passed to child) Home Gardens: Small to moderate increase Other exposure pathways: Not evaluated (less common) ERM s analysis of non-inhalation pathway risks: increases range from 1.3 to 3.3 for the overall non-inhalation pathway risk.

12 Non-Cancer Health Effects Expressed as a Hazard Index (HI); Significant if > 1.0 Inhalation hazard index based on air concentration: Hazard Index (HI) = Calculated Airborne Concentration Reference Exposure Level (REL) Numerator adjusted to account for new breathing rates Chronic Health Effects from Long-Term Exposures: Modeled Airborne Concentrations Adjusted Concentrations (Breathing Rates) Non-Inhalation Parameter Adjustments 12 Acute Health Impacts from Short-Term (Hourly) Exposures Calculated airborne concentration not adjusted OEHHA periodically updates RELs (e.g., recent update to benzene 1-hr acute REL) Higher Chronic Hazard Index

13 Updating Old HRAs: AERMOD vs ISCST Many older HRAs were developed using the ISCST dispersion model, the new guidelines will utilize the AERMOD dispersion model. Effects on Predicted Exposure Concentrations using AERMOD: High Frequency of Low Wind Speed Condition (less than 1 m/s) can cause significant increases in maximum predicted exposure concentrations due to changes in algorithms between AERMOD and ISCST. Effects of surrounding terrain on specific receptor locations may lead to an increase in predicted concentrations between AERMOD and ISCST, especially in very rough terrain regions. The use of wind directional-specific land use data in AERMOD may also lead to changes in maximum predicted exposure concentrations. Net effects may result in higher overall cancer risks or changes in the location of maximum areas in cases where these effects are significant. 13

14 HARP 2 Model 14

HARP 2 Overview 15 Health Risk Assessment Software History ACE 2588 1992 Dispersion Model ISCST HARP 2003 Dispersion Model ISCST AERMOD (use of ONRAMP) CALPUFF (use

15 HARP 2 Overview 15 Health Risk Assessment Software History ACE Dispersion Model ISCST HARP 2003 Dispersion Model ISCST AERMOD (use of ONRAMP) CALPUFF (use of ONRAMP) HARP AERMOD HARP 2 - Changes in Calculated Health Effects OEHHA Guidelines Toxicity Factor Changes Dispersion Model Modifications Meteorological Data

HARP 2 Three Modules Emissions Inventory Module (EIM) Manage Emissions Inventory Database Hazard Identification Facility Prioritization Scoring for AB2588 Air Dispersion Modeling & Risk Tool (ADMRT)

16 HARP 2 Three Modules Emissions Inventory Module (EIM) Manage Emissions Inventory Database Hazard Identification Facility Prioritization Scoring for AB2588 Air Dispersion Modeling & Risk Tool (ADMRT) Perform Dispersion Modeling in the Program (AERMOD) Input AERMOD plot files (for every source, every averaging period) Exposure Assessment + Dose-Response + Risk Characterization Combine with emissions files & toxicity factors to calculate health risks 16 Risk Assessment Standalone Tool (RAST) Import actual pollutant concentrations by receptor Combine with toxicity factors to calculate health risks Dose-Response + Risk Characterization

ERM s Assessment of HARP 2 To Date Available Outputs Various outputs in AERMOD plot file format Single receptors by chemical Risk contours over receptor field KML files for

17 ERM s Assessment of HARP 2 To Date Available Outputs Various outputs in AERMOD plot file format Single receptors by chemical Risk contours over receptor field KML files for import to Google Earth Cancer burden and population exposures Challenges Data Management Inputs Outputs Lack of File Names and Paths for QA Purposes Potential Hardware Limitations 17

18 Example Run: HARP vs HARP 2 Identical AERMOD Output Files Hypothetical Boiler Co-Firing Natural Gas and Heavier Fuel Inhalation and Non-Inhalation Exposure Pathways Included Description 2003 OEHHA Guidelines and HARP 2003 OEHHA Guidelines and HARP - Age Sensitive Factors (current BAAQMD requirements) 2015 OEHHA Guidelines and HARP 2 Percent Increase HARP 2 vs. HARP With ASFs Percent Increase HARP 2 vs. HARP Without ASFs Cancer Risk - 70 Year Exposure Cancer Risk - 30 Year Exposure Cancer Risk - 9 Year (Child) Exposure Chronic HI Acute HI N/A N/A Percent Increase 185% 224% 215% N/A N/A 314% 585% 1040% 140% 100% 18

19 California Air District Implementation

20 SCAQMD Summary of SCAQMD Approach Relative to the New OEHHA Guidelines Draft rule changes are positioned to avoid future rule changes by being less prescriptive Use age bins rather than a single 0-70 age group and age sensitivity factors Allowing the use of 30-year exposure period for residential as an alternative to 70 years Use different breathing rates per age group proposing 95% for initial analyses, but may accept 95/80% in refined assessments Positioning to use updated OEHHA guidelines average exposure factors for non-inhalation pathways 20

21 SCAQMD 21 SCAQMD Governing Board Presentations and Preliminary Draft Staff Report Residential cancer risk: About 3 times higher for single pathway and up to 6 times higher in multi-pathway Public notices expected to increase for Rule 1401/ times more notices for facilities 5-10 times more notices to households Approximately 80% of facilities with HRA will require updates More Facilities Expected to be Subject to AB2588 and to Risk Reduction Measures CEQA Impacts Expected to Increase More projects upgraded to EIRs due to construction Diesel Particulate Matter Construction (1 lb/day DPM) over 6 months will result in risk >10 per million

22 SCAQMD Work plan to phase in and prioritize implementation Scheduled Public Workshops proposed amendments to Rules 1401/1402 and Rule 212 March 31 st 2 pm Riverside April 1 st 10 am Diamond Bar April 2 nd 10 am Buena Park April 2 nd 4 pm Wilmington Separate meetings to discuss effect on CEQA 22

San Joaquin Valley APCD 23 Summary of SJVAPCD Approach Relative to the New OEHHA Guidelines Use age bins rather than a single 0-70 age group and age sensitivity factors 70-year exposure period for

23 San Joaquin Valley APCD 23 Summary of SJVAPCD Approach Relative to the New OEHHA Guidelines Use age bins rather than a single 0-70 age group and age sensitivity factors 70-year exposure period for residential (new OEHHA recommends 30 years) 40-year exposure period for worker (new OEHHA recommends 25 years) Use different breathing rates per age group -- awaiting Risk Management Policy on use of 95/80 th percentile breathing rate approach

24 San Joaquin Valley APCD Risk Thresholds AB in one million facility risk requires notification to impacted individuals and workplaces AB in one million facility risk requires risk reduction audit and plan TBACT required for each source with greater than 1 in one million risk Permitting and CEQA 20 in one million threshold for permit application disapproval and CEQA significant impact The Final Draft Staff Report on Update to the District s Risk Management Policy was made available March 18, 2015 and can be found here: 24

25 BAAQMD CEQA / CAPCOA s Recommendations for adoption of OEHHA Exposure Factors. BAAQMD recommends a 30 year exposure duration for residents Breathing Rates (95 th percentile for greater than 2 years and 80 th percentile for greater than 2 years Units Trimester 0<2 2< L/kg-day Age Sensitivity Unitless Fraction of time at home Unitless Exposure Duration Years

26 BAAQMD November 17, 2014 Staff Report to BAAQMD Board on then-draft OEHHA HRA Guideline Revisions Risk estimates will increase due to: breathing rates; multi-pathway exposure factors; and age sensitivity factors (which were noted already in use) Risk estimates will decrease due to exposure durations BAAQMD staff estimated a 2 to 5 times increase in risk predictions BAAQMD staff estimate of District workload increase: 150 new permit applications per year may require HRAs 750 existing facilities may require further prioritization analyses 300 existing facilities may require updated AB2588 HRAs Next Steps : Prepare Regulation 2-5 and policy amendments 2015 Work with stakeholders on outreach and risk communication 27

27 BAAQMD Updates from Engineering and Planning Divisions (March 2015): Engineering Division: Wait on a revised Regulation 2 Rule 5 (the BAAQMD s NSR Rule for Toxic Air Pollutants) Planning Division: Continue to process CEQA under old guidelines until CAPCOA/CARB Risk Management Guidelines are adopted 28

28 Takeaway Points and Conclusion

29 Main Take-Away Points on Updated HRA Guidelines 1. The new OEHHA HRA Guidelines will result in increases in cancer risk predictions. How much depends on type of facility and where it is located 2. New HRAs will use AERMOD 3. Interim challenges due to new Health Risk Assessment tools 4. Several California air districts have been in the process of planning for the implementation of the revised OEHHA HRA guidelines 5. The following programs will impact more existing/new facilities: AB 2588 Hot Spots Program (higher health risk estimates) New/modified source permitting (more T-BACT reviews) CEQA analyses for capital projects (significance findings) Public noticing (programs with public notice requirements) Awaiting the release of State-wide Risk Management Guidelines

30 Coming Soon Roundtable Sessions Walnut Creek Lunchtime April 23 rd Long Beach TBD Considering other California Locations Accepting requests for meetings and presentations A link to download slides from today s webinar will be circulated to all participants. Contact for additional information Zoe Desouky at zoe.desouky@erm.com 31

31 Questions? Lynn McGuire, PE, Western Division Air Practice Leader (925) , Health Risk Assessment Subject Area Experts: John Koehler, Sc.D., AQ Program Director, Permitting/Public Health (925) , Danny Kringel, AQ Technical Director, So Cal Modeling Lead (949) , Vicki Hoffman, AQ Program Director, Nor Cal Modeling Lead (925) , 32

Sacramento Rendering Company Health Risk Assessment

Sacramento Rendering Company Health Risk Assessment The SMAQMD regulates emissions of toxic substances under Rule 402 and SMAQMD s guidance document, Health Risk Management Programs for Existing, Modified