Triennial Review of Groundwater Quality Standards 15A NCAC 2L .0202

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Triennial Review of Groundwater Quality
Standards15A NCAC 2L .0202

• Sandra Moore, Water Quality Standards Coordinator
• DWQ Planning Section
• Classifications Standards Unit

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Presentation Overview

• Intent of 2L rules
• How standards are established
• Triennial review process
• Proposed changes

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Intent of 2L Rules

• Maintain and preserve
• Prevent and abate pollution
• Permit management for best usage
• Restore quality if degraded

15A NCAC 2L .0103
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Groundwater Quality Standards

• Maximum allowable concentrations
• Protect groundwaters as a resource
• Protect human health

15A NCAC 2L .0202(g)
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How Standards Are Established

• Non-cancer effects
• Cancer (One-in-a-million risk)
• Taste threshold
• Odor threshold
• National Primary DW Std (MCLs)
• National Secondary DW Std

15A NCAC 2L .0202 (d)
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Triennial Review Process

• DWQ SOP
• DPH and DWM review
• EMC approval

15A NCAC 02L .0202(f)
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Proposed Changes

• Incorporate 7 interim stds
• Add formaldehyde
• Remove 10 stds
• Remove 2 interim stds
• Make 15 more stringent
• Make 12 less stringent

15A NCAC 2L .0202(g)
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Proposed Edits

• Meaning of detection" .0202(c)
• Units of measure from ppm to ppb
• One scientifically significant figure
• 10 chemical names updated

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Revision to Tetrachloroethylene

• Proceed with proposed standard (0.07 ug/L)?
• Leave current standard in place (0.7
  ug/L)?

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Estimated Rulemaking Timeline

• June 1 Comment period ends
• June-August Prepare response to comments/ EMC
  report
• September 10 Report to EMC
• October 15 Rules Review Commission
• November 1 Earliest effective date

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DWQ CSU web sitehttp//h2o.enr.state.nc.us/csu/

• Groundwater Standards Information
• Groundwater Triennial Review

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Comments by June 1, 2009 to
Sandra Moore DENR/DWQ Planning Section 1617 Mail
Service Center Raleigh, N.C. 27699-1617 Phone
919 807-6417 Fax [phone] Email
Sandra.moore_at_ncmail.net May 1 Sandra.moore_at_ncdenr
.gov