The Department of Toxic Substances Control (DTSC) is currently drafting regulations to add Chapter 51.3 to the California Code of Regulations, under Title 22, Division 4.5. This rulemaking proposes to require that any human health risk screening or risk assessment shall use the most protective of the three federal and state accepted toxicity criteria sources for each cancer and non-cancer contaminant of concern for any site in California.
DTSC will host a public workshop to discuss proposed regulations that would specify toxicity criteria for human health risk-based screening levels, action levels, and remediation goals. The workshop information can be found below in the notice text that was published in the Office of Administrative Law’s Notice Register. This workshop is the first step toward beginning the formal rulemaking process in 2017.
In addition to this workshop, DTSC would like to extend the opportunity for interested stakeholders and the public to ask questions or provide feedback on this proposed regulation during this informal review period. Comments will be accepted until January 16, 2017. Please note that due to the informal nature of the workshop, responses will not be issued to comments received; however, all comments received before the January 16, 2017 comment period will be considered. The following is the official information was published in the Notice Register:
December 12, 2016,
1:00 PM – 4:00 PM
DTSC Cal Center Offices
8800 Cal Center Drive
Board Room, 1st floor,
Sacramento, CA. 95826
DTSC is taking this action because it has determined that calculating screening levels and cleanup goals from a single source of toxicity criteria does not always provide the best protection to human health. DTSC proposes to require that any human health risk screening or human health risk assessment shall use the most protective of the following three toxicity criteria sources for each cancer and non-cancer contaminant of concern:
1. Office of Environmental Health and Hazard Assessment Chemical Database, or its successor. As of November 12, 2015, the database is available online athttp://oehha.ca.gov/tcdb/index.asp
2. US EPA Integrated Risk Information System (IRIS) database. As of November 12, 2015, the database is available online at http://www2.epa.gov/iris
3. Provisional Peer-Reviewed Toxicity Value (PPRTV). As of November 19, 2015, these values are available online at http://hhpprtv.ornl.gov/quickview/pprtv.php
The proposed regulation follows:
Division 4.5, Environmental Health Standards for the Management of Hazardous Waste Add Chapter 51.3, Article 1, sections 69000.1 - 69000.3 as follows:
Chapter 51.3 Human Health Toxicity Criteria for Cleanup.
69000.1. Purpose and Applicability
This chapter applies to hazardous waste and hazardous substance release sites subject to the provisions of Health and Safety Code, division 20, chapters 6.5, 6.8 and/or 6.82. It requires that the toxicity factors specified in 69000.3 be used to establish human health risk-based action levels and remediation goals.
69000.2. Action Levels, Screening Levels, Remediation Goals, and Point of Departure for Evaluation of Cleanup Alternatives
(a) The point of departure for action level and screening level determinations, and remediation goals, based on human health risk is: (1) An incremental excess lifetime cancer risk to an individual of 1 x 10-6, and (2) A cumulative hazard index across all pathways and contaminants of concern (COCs) of 1.0. (b) The above action levels, screening levels and remediation goals shall be calculated using the toxicity criteria specified in section 69000.3.
69000.3. Applicable Toxicity Criteria
Any human health risk screening or human health risk assessment shall use the most protective of the following three toxicity criteria sources for each cancer and noncancer contaminant of concern:
(a) The peer reviewed unit risk factors, inhalation and oral slope factors, and chronic reference exposure levels (cRELs, both inhalation and oral) from the Office of Environmental Health and Hazard Assessment Chemical Database, or its successor.
(b) The unit risk factors, inhalation and oral slope factors, reference doses (RfD), and reference concentrations (RfC), from the US EPA Integrated Risk Information System (IRIS) database, or its successor.
(c) The unit risk factors, inhalation and oral slope factors, reference doses (RfD), and reference concentrations (RfC), from the US EPA Provisional Peer-Reviewed Toxicity Value (PPRTV) database, or its successor
In addition to the draft proposed language above, DTSC will solicit comments on the alternative concept of implementing a narrative standard to require use of state Toxicity Criteria when they are more protective than the other two federal sources.
All members of the public, the regulated community, and other stakeholders are invited to attend the preliminary workshop during which to voice comments. All are also welcome to submit written comments until January 16, 2017 to the following address:
Department of Toxic Substances Control
8800 Cal Center Drive
Sacramento, California 95826
Attn: Mr. Kevin Depies