1. Arsenic Acceptable Ambient Level Revision
Joelle Burleson
Department of Environment & Natural Resources
Division Of Air Quality
September 12, 2013

2. Acronyms AAL - Acceptable Ambient Level
DENR - Department of Environment and Natural Resources
DAQ - Division of Air Quality
DWR - Division of Water Resources
EPA – Environmental Protection Agency
EMC - Environmental Management Commission
IRIS – Integrated Risk Information System
SAB - Science Advisory Board
TAP- Toxics Air Pollutant
TPER- Toxics Permitting Emission Rate

3. Background NC has a Health Risk Based State Air Toxics Program
Establishes Acceptable Ambient Level (AAL) Guidelines and Emission Rates Requiring a Permit against which a Facility’s Emissions Impact to Ambient Air at or Beyond Property Boundary is Reviewed
DENR Secretary’s Science Advisory Board (SAB) Studies Toxicological Effects of Toxic Air Pollutants (TAPs) and Advises EMC Regarding Necessary Level of Control for Protection of Human Health and Environment

4. Arsenic Acceptable Ambient Level (AAL) Revision
Proposed Rule Revises Arsenic AAL from 2.3 x 10-7 mg/m3 to 2.1 x 10-6 mg/m3
Proposed Rule Revises Associated Emission Rate Requiring a Permit (aka TPER or Toxics Permitting Emission Rate) from lbs/yr to lbs/yr
Request to Proceed to Hearing Approved by EMC March 14, 2013
Hearing
Comment Period Closed June 14, 2013

5. Arsenic Acceptable Ambient Level (AAL) Revision
Hearing Officer’s Report Presented to EMC July 11, 2013 Recommending Adoption of Proposed Amendments
EMC Members Raised Concerns:
SAB Methodology – Use of Different Calculation Methodology vs. New Data
Was Atmospheric Deposition and Ingestion Considered?
Ongoing EPA Update of Integrated Risk Information System (IRIS) Arsenic values
EMC Voted to Delay Action until September Meeting

6. Arsenic Acceptable Ambient Level (AAL) Revision
Anticipate Action Item at November EMC Meeting
SAB Representatives, DAQ Staff, DWR Staff Available to Respond to Questions
July EMC Meeting Minutes Available at:
Hearing Record Available at:
Potential Effective Date: January 1, 2014

7. Contact Information
Joelle Burleson
(919)