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

PRESENTATION OVERVIEW

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• 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

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

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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

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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

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HISTORY – REFERENCE SITE SELECTION

Were not adjacent to: • feed lots, • equipment sheds, • bulk storage yards, etc., or • areas with obvious vegetation

damage

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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 0.5 - 0.6 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)

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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

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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

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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

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RELEVANCE TO THE MINISTRY – P28

Provincial estimate (Protocol 28 new) • 95th 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

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RELEVANCE TO THE MINISTRY – P4

Regional estimates (Protocol 4) • 95th percentile for each administrative regions • Used by responsible parties to adjust local background at a site or for soil

relocation

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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

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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

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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)

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QUESTIONS? JENNIFER PUHALLO

JENNIFER.PUHALLO@GOV.BC.CA OR (250) 371-6287

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 email the presenter following the webinar.

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

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

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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

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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

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NEW Protocol 30 “Classifying Substances as Carcinogenic”

Allows for more frequent updates to reflect new science

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 CCME

Group 1: Carcinogenic to humans Group 2A: Probably carcinogenic to humans

PAHs that are considered “carcinogenic” or “possibly carcinogenic”

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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”

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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)

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Eliminate the risk

• 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

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

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TECHNICAL GUIDANCE 7

Changes of note: • Guidance on how to use Protocol 30 “Classifying Substances as

Carcinogenic”

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• 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

• 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)

TECHNICAL BULLETINS

REPEALED Technical Bulletin 1 “Risk Assessment Evaluation. Occupational Dermal Exposure from Contaminated Surface Water or Groundwater”:

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Moved into Technical Guidance 7

To be moved into Procedure 10

TO BE REPEALED Technical Bulletin 2 “Requirements for Human Health and Ecological Risk Assessment Reports”:

Risk management

QUESTIONS ? LIZZY MOS

LIZZY.MOS@GOV.BC.CA OR (778) 698-4930

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 email the presenter following the webinar.