PROVINCIAL AND REGIONAL BACKGROUND CONCENTRATIONS IN SOIL CSR STAGE 11 AMENDMENT WEBINAR #2 NOVEMBER 21, 2017

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1 PROVINCIAL AND REGIONAL BACKGROUND CONCENTRATIONS IN SOIL CSR STAGE 11 AMENDMENT WEBINAR #2 NOVEMBER 21, 2017 Jennifer Puhallo Risk Assessment Officer This PowerPoint presentation and a recording of the audio will be posted on the web following the webinar

2 PRESENTATION OVERVIEW Brief history of establishing background concentrations in soil Impetus for making changes in Stage 10/11 Relevance of the changes to the Ministry Other related changes made in Stage 10/11 TG17 P4 P28 new 2

3 HISTORY - BACKGROUND CONCENTRATIONS IN SOIL Collected background soil quality data for selected metals From all of its administrative regions of the province Additional background sampling in the Greater Vancouver area because of very active redevelopment of commercial and industrial properties 3

4 HISTORY REFERENCE SITE SELECTION Ideal background sites exhibited: uniform vegetation uniform land use, and approximately one hectare in size Representative of the land use within their locale Preference given to vacant land, wooded sites, agricultural fields, parkland, or larger residential lots 4

5 HISTORY REFERENCE SITE SELECTION Did not include: mineralized areas to avoid bias from higher metal concentrations obvious soil boundaries such as major changes in drainage, soil texture or topography 5

6 HISTORY REFERENCE SITE SELECTION Were not adjacent to: feed lots, equipment sheds, bulk storage yards, etc., or areas with obvious vegetation damage 6

7 HISTORY SAMPLING AND ANALYSIS Soil sampling performed (for each site): locate four discrete sampling points collection of soil from two discrete and consistent depth increments (0-0.1 m surface and m sub-surface ) one soil sample for metals analysis and another for organics analysis (from each depth) preparation of a split sample for selected organic analysis and archival purposes (from each depth) 7

8 HISTORY SAMPLING AND ANALYSIS Nitric perchloric preparatory techniques pre December 1997 Aqua regia preparatory techniques after December 1997 Pre-Stage 10/11 regional background soil estimates in Table 1, Protocol 4 were based on aqua regia 8

9 IMPETUS FOR CHANGE - SALM Revised method was prepared for BC ENV by the BCELTAC to provide improved consistency of results for metals in soil Feb 2001 Version 1 of SALM Method was introduced; incorporated into BC ENV Lab Manual July 2009 Version 2 of SALM Method included in the BC ENV Lab Manual; method revised from performance based to prescriptive Archived background soil samples still available were reanzlyzed using SALM method 9

10 IMPETUS FOR CHANGE REANALYSIS AND RESULTS SALM is intended to dissolve those metals that may be environmentally available Achieves near complete recoveries of some important metals, but many others are only partially recovered Metals not dissolved with this method are unlikely to be of environmental consequence Aqua regia vs. SALM some concentrations went up, some went down 10

11 RELEVANCE TO THE MINISTRY P28 Provincial estimate (Protocol 28 new) 95 th percentile of entire dataset, rounded 2016 Provincial estimates based on SALM with some exceptions Insufficient detectable results (n < 10 ) Not analyzed using SALM SALM not the official method of analysis Lead is based on SALM but rounding based on Director s decision Used by Ministry to background adjust soil standards 11

12 RELEVANCE TO THE MINISTRY P4 Regional estimates (Protocol 4) 95 th percentile for each administrative regions Used by responsible parties to adjust local background at a site or for soil relocation 12

13 RELEVANCE TO THE MINISTRY TG17 Background soil database (TG17) Individual data points for each reference site Organized by locales within administrative regions Can also be used by responsible parties to adjust local background at a site 13

14 OTHER RELATED CHANGES - STAGE 11 Changes to Technical Guidance 17 and Protocol 4: Updated language and terminology Release" to Director's decision on local background Stage to Options (P4) Reorganized so procedures fall within each option, not a separate section (P4) Updated figures in P4 14

15 OTHER RELATED CHANGES STAGE 11 Clarified: Areas potentially impacted by point source contamination do not meet the criteria for obtaining a Director's decision on local background Using Table 1 regional background estimates does not require a separate application as long as it is clear how these background estimates were applied at the site How to apply regional estimates to soil at depth at a site (as long as no deep rooted vegetation present) 15

16 QUESTIONS? JENNIFER PUHALLO OR (250) Advice provided during this webinar is based on information available at the time of recording and may be subject to change. This PowerPoint presentation and a recording of the audio will be posted on the web. If you do not wish your question to be on the public record, please the presenter following the webinar.

17 SUMMARY OF RISK ASSESSMENT UPDATES CSR STAGE 11 AMENDMENT WEBINAR #2 NOVEMBER 21, 2017 LIZZY MOS RISK ASSESSMENT OFFICER This PowerPoint presentation and a recording of the audio will be posted on the web following the webinar

18 PRESENTATION OVERVIEW Carcinogenic substances & Protocol 30 Classifying Substances as Carcinogenic Technical Guidance 7 Supplemental Guidance for Risk Assessments Technical Bulletins 1 and 2 NOT Protocol 13 Screening Level Risk Assessment (Webinar #6) Risk assessment 18

19 CARCINOGENS Former CSR definition of carcinogenic substance : carcinogenic substance means any chemical classified by a) The International Agency for Research on Cancer as a group 1 or group 2A carcinogen, or b) The United States Environmental Protection Agency as a group A or group B1 carcinogen Isolate the risk 19

20 CARCINOGENS NEW CSR definition of carcinogenic substance was introduced as part of the Stage 10 Amendment: carcinogenic substance means any chemical classified as carcinogenic in accordance with a director s protocol NEW Protocol 30 Classifying Substances as Carcinogenic Allows for more frequent updates to reflect new science 20

21 PROTOCOL 30 SUMMARY US EPA Weight of Evidence (2005,1996) US EPA Alphanumeric descriptors (1986) Carcinogenic to humans Likely to be carcinogenic to humans Known or likely human carcinogen Group A: Human carcinogen Group B1: Probable human carcinogen IARC Group 1: Carcinogenic to humans Group 2A: Probably carcinogenic to humans CCME PAHs that are considered carcinogenic or possibly carcinogenic 21

22 PROTOCOL 30 Protocol 30 classifies a substance as a carcinogen, but does not include instruction on how to risk assess carcinogens. It does not: Prescribe what sources of slope factors to use Prescribe that the source of the classification should also be used as the source of the slope factor Intend risk assessment in the absence of appropriate slope factors Intend risk assessment of carcinogenic effects if a substance is only carcinogenic by an incomplete exposure pathway Risk assessments should use the most recent information available This information is contained in TG7 Supplemental Guidance for Risk Assessments 22

23 PROTOCOL 30 Important considerations: Lead is not currently considered a carcinogen Although listed by IARC as Group 2A, the ministry awaits for further scientific evidence and jurisdictional agreement (see TG7) Standards that were adopted from the US EPA Regional Screening Levels were not screened against the Protocol 30 classification as part of the CSR Stage 10 Amendment The ministry may correct this in future amendments Eliminate the risk 23

24 TECHNICAL GUIDANCE 7 UPDATED Technical Guidance 7 Supplemental Guidance for Risk Assessments (version 5) Mostly minor changes/additions: Precluding conditions for SLRA (updated P13) New guidance from other jurisdictions Reference to new ministry guidance/protocols P21 Water Use Determination P22 Vapours P28 Standards Derivation Methods P30 Classifying Substances as Carcinogenic Revision history 24

25 TECHNICAL GUIDANCE 7 Changes of note: Guidance on how to use Protocol 30 Classifying Substances as Carcinogenic New TRV selection hierarchy reflective of Protocol 28 Standards Derivation Methods Including ministry TRVs for lead (toddler/adult), sodium, chloride No longer giving preference to HC for mercury and lead New ecological protection goals referenced (Protocol 28) Protocol 1 Tier 1 Ecological Risk Assessment caution for use Protocol 1 is outdated and conflicting with other documents Components of it may be used within the context of other ministry risk assessment guidance, BUT: ERAs must be accompanied by a Protocol 13 or Protocol 20 checklist 25

26 TECHNICAL BULLETINS REPEALED Technical Bulletin 1 Risk Assessment Evaluation. Occupational Dermal Exposure from Contaminated Surface Water or Groundwater : Moved into Technical Guidance 7 TO BE REPEALED Technical Bulletin 2 Requirements for Human Health and Ecological Risk Assessment Reports : To be moved into Procedure 10 Risk management 26

27 QUESTIONS? LIZZY MOS OR (778) Advice provided during this webinar is based on information available at the time of recording and may be subject to change. This PowerPoint presentation and a recording of the audio will be posted on the web. If you do not wish your question to be on the public record, please the presenter following the webinar.