The U.S. Environmental Protection Agency (EPA) develops National Ambient Air Quality Standards (NAAQS) to protect human health and the environment. DAQ is required to develop long-term planning documents such as State Implementation Plans (SIPs) to demonstrate how the NAAQS will be achieved, maintained, and enforced. After an area reaches attainment, a Redesignation/Maintenance Plan is developed to demonstrate maintenance for at least the next 10-year period. These Maintenance Plans also become part of the State SIP. DAQ also develops Transportation Conformity Plans, in collaboration with the Regional Transportation Commission of Southern Nevada (RTC), the MPO for Clark County, to address transportation conformity issues in Southern Nevada.
Currently, portions of Clark County are classified as nonattainment for Particulate Matter (PM10), Carbon Monoxide (CO). Clark County is a maintenance area for the 1997 ozone NAAQS and for CO. A Maintenance Plan and Redesignation Request for PM10 has been submitted to EPA.
Particulate Matter (PM10)
The Las Vegas Valley (HA 212) within Clark County is classified serious nonattainment for PM10. DAQ submitted a State Implementation Plan in 2001, which explains how the area will attain the NAAQS for PM10. The plan is the cumulative program of all pollution control strategies, control measures, emission inventories, attainment demonstration, and state statute and local rules implemented. Final U.S. EPA approval of the plan was effective July, 2004.
Subsequently, DAQ submitted a Milestone Achievement Report (MAR) in June 2007. The MAR documents Clark County’s attainment of the 24-hour PM10 NAAQS. EPA made the determination that the Las Vegas Valley is in attainment with the PM10 NAAQS on August 3, 2010 (75 FR 45485), and will redesignate the area to attainment upon approval of the pending maintenance plan and request for redesignation, that was submitted to EPA in August 2012.
The Natural Events Action Plan describes the actions and programs DAQ uses to mitigate the effects of high-wind events on levels of particulate matter in the Las Vegas and Apex Valleys. The plan exceeds the current requirements of the March, 2007, EPA Exceptional Events Rule.
|PM10 Redesignation Request and Maintenance Plan (2012)
PM10 Maintenance Plan - without Appendices
App A - Technical Support Document
App B - Documentation of the Public Review Process
|Milestone Acheivement Report (2007)
Milestone Achievement Report (2007) – without Appendices
App A – Monitoring Data
App B – High Wind Events
App C – Saturation Monitoring Study
App D – Land and Road Soil Stabilization Study
App E – Refined Emission Factors
App F – Construction Inventory
App G – RTP Chapter 5
App H – Proportional Rollback Model
|Natural Events Action Plan (2005)
||NEAP (without Appendices)
App A – EPA Natural Events Policy
App B – Geography and Climatic Summary
App C – Public Health & Outreach Materials
App D – Clark County Air Quality Regulations
App E – Contracted Water Truck policy
App F – Example High Wind Event Justification Package
App G – Public Notice and Review
App H – Public Comments and Responses
|PM10 State Implementation Plan for Clark County (2001)
||PM10 SIP Plan (without Appendices)
App A - Design Value Determination
App B - Emission Inventory Methodology
App C - Estimation of Valley-Wide PM10 Emissions
App D - PM10 Emissions Inventory of Sources Surrounding Monitoring Sites
App E - Inventory Projections Methodology and Calculations
App F - Control Measure Development Process
App G – Air Quality Regulations and Section 94 Handbook
App H – Clark County Health District Resolutions
App I - Letter from Nevada Department of Motor Vehicles and Public Safety
App J - Street Sweeping Equipment and Paved Road Cleanup Programs
App K – Rollback Methodology
App L – Controlled Emission Inventory Development
App M – Reasonable Further Progress Inventory of 2003
App N – Mobile Source Emissions Budget
App O – Public Review Process
App P – Comments Received
App Q – Public Hearing Documentation
App R – Residential Wood Combustion Control Measures
Carbon Monoxide (CO)
DAQ submitted a CO State Implementation Plan in 2000. This plan describes the control measures and technologies to bring the Las Vegas Valley into compliance with the CO NAAQS. A Revision of the SIP was submitted in 2005 to update the CO emissions budgets using the latest model approved by EPA for transportation conformity determinations (MOBIL6). A Federal Register notice denoting EPA's determination of attainment for CO NAAQS within the Las Vegas Valley was issued in June 2005. A CO Maintenance Plan and formal request for redesignation to attainment was submitted to the EPA in 2008 and was approved on September 27, 2010. The Clark County nonattainment area was redesignated attainment effective October 21, 2004.
EPA made the determination that Clark County is in attainment with the 1997 Ozone NAAQS on March 29, 2011 (76 FR 17343). EPA redesignated the area to attainment effective February 7, 2013 (78 FR 1149).
An Ozone Early Progress Plan that provides the basis for establishing early transportation conformity budgets for the Clark County, Nevada, 8-hour Ozone nonattainment area was submitted to EPA in 2008, and approved in 2009. On November 13, 2012, EPA publiched the proposed rule for Approval of the Maintenance Plan and Redesignation of Clark County for the 1997 8-Hour Ozone Standard.
The Federal Clean Air Act (CAA) requires the County to prepare Infrastructure SIPs (I-SIP) every time EPA promulgates a new, or revises an existing NAAQS. The purpose of the I-SIP is to demonstrate Clark County has the programs in place to implement, maintain, and enforce the NAAQS. The I-SIP addresses the following air quality program elements: permitting; air quality modeling; enforcement; ambient air monitoring; and, confirmation of adequate personnel, resources, and legal authorities. An I-SIP is required whether or not an area is in compliance with a new air quality standard.
The Ozone (O3) NAAQS was revised in 2008 and the I-SIP was submitted to NDEP in February 2013 for inclusion as a revision to the NV SIP.
The Nitrogen Dioxide (NO2) NAAQS was revised in 2010 and the I-SIP was submitted to NDEP on December 11, 2012 for inclusion as a revision to the NV SIP.
The Lead (Pb) NAAQS was revised in 2008 and the I-SIP was submitted to NDEP on July 13, 2012 for inclusion as a revision to the NV SIP.
In 2009, the Nevada Department of Environmental Protection (NDEP) submitted a consolidated I-SIP submittal for the 1997 8-hour O3 NAAQS, and the 1997 and 2006 NAAQS for PM2.5. This was a joint effort between NDEP, the Washoe County Health District and DAQ. EPA published a proposed rule for approval of the I-SIP on August 3, 2012. The final rule was promulgated on 10-23-2012.
Transportation Conformity Plan
The Transportation Conformity Plan details consultation criteria, policies, and procedures that applicable local, state and federal agencies must follow when addressing transportation conformity issues within Clark County. DAQ updated the plan in 2008. In July 2008, EPA issued a finding that the Transportation Conformity Plan fulfilled the requirements in 40 CFR Part 51, Appendix V. Subsequently, EPA issued a direct final rule in November 2008.
For more information or questions about SIP documents contact Rodney Langston (702) 455-1661 for particulate matter, Robert Tekniepe at (702) 455-4063 for CO and transportation conformity, and Jean-Paul Huys (702) 455-1684 for ozone.