Chapter Eight - Monitoring Strategy 

8.1 INTRODUCTION 

8.2 NEVADA’S REGIONAL HAZE VISIBILITY MONITORING 

STRATEGY 

8.3 COORDINATION WITH §51.305 MONITORING STRATEGY 

REQUIREMENT 

8.4 ASSOCIATED REGIONAL HAZE MONITORING STRATEGY 

REQUIREMENTS 

8.5 OVERVIEW OF IMPROVE SITE AT THE JARBIDGE WILDERNESS 

AREA 

8.6 COMMITMENT TO FUTURE MONITORING 

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8.1 INTRODUCTION 

The Regional Haze Rule (RHR) at 40 CFR 51.308(d)(4) requires states to submit a monitoring 

strategy for measuring, characterizing and reporting of regional haze visibility impairment that is 

representative of all mandatory Class I areas within the state. The regional haze monitoring 

strategy must also coordinate with the monitoring strategy required in 40 CFR 51.305 for 

reasonably attributable visibility impairment, as well as provide for a variety of other 

requirements designed to evaluate reasonable progress toward meeting national visibility goals. 

8.2 NEVADA’S REGIONAL HAZE VISIBILITY IMPAIRMENT MONITORING 

STRATEGY 

Visibility conditions are presently measured by the Interagency Monitoring of Protected Visual 

Environments (IMPROVE) monitoring network. In the mid-1980’s, the IMPROVE network was 

established to measure visibility impairment in mandatory Class I areas throughout the United 

States. The monitoring sites are operated and maintained through a formal cooperative 

relationship between the USEPA and Federal Land Managers (FLM) agencies, which include: 

the National Park Service, the U.S. Fish and Wildlife Service, the Bureau of Land Management 

and the U.S. Forest Service. 

The objectives of the IMPROVE program are: 

1. To determine current visibility and aerosol conditions in mandatory Class I areas; 

2. To identify chemical species and emission sources responsible for existing human-made 

visibility impairment; 

3. To document long-term trends for assessing progress towards the national visibility 

goals; and 

4. With the enactment of the regional haze program, to provide regional haze monitoring 

representing all visibility in mandatory Class I areas, where practical. 

Given that the IMPROVE monitoring data from 2000 through 2004 serves as the baseline for the 

regional haze program, the future regional haze monitoring strategy must necessarily be based 

on, or directly comparable to the IMPROVE program. The IMPROVE measurements provide 

the only long-term record available for tracking visibility improvement or degradation. The data 

collected at these sites are used by a variety of professionals in industry and at regulatory 

agencies to better understand and protect the visual air quality resources in mandatory Class I 

areas. The IMPROVE network documents the visual air quality in wilderness areas and national 

parks throughout the United States. 

Nevada’s regional haze monitoring strategy relies on information generated through the 

IMPROVE network for the Jarbidge Wilderness Area (Jarbidge WA). It is expected that the 

IMPROVE program will: 

1. Maintain a stable configuration of the individual monitors and sampling sites, and 

stability in network operations for the purpose of continuity in tracking reasonable 

progress trends; 

2. Assure sufficient data capture at each site for all visibility-impairing species; 
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3. Comply with the USEPA quality control and assurance requirements; and 

4. Prepare and disseminate periodic reports on IMPROVE operations. 

8.3 COORDINATION WITH §51.305 MONITORING STRATEGY REQUIREMENT 

Nevada is subject to a federal visibility protection plan (visibility FIP) as opposed to having an 

approved visibility protection SIP. Nevada’s visibility FIP is found at 40 CFR 52.1488. The 

visibility monitoring strategy provisions of 40 CFR 52.26 are incorporated into Nevada’s 

visibility FIP. 40 CFR 52.26(c)(1) requires the USEPA in cooperation with the appropriate FLM 

to monitor visibility within each visibility protection area in the state. Accordingly, the FLMs 

operate the IMPROVE program which addresses visibility monitoring at the Jarbidge WA, as 

well as visibility protection areas outside the state, and establishes background visibility for the 

purposes of the regional haze requirements. 

Nevada’s regional haze monitoring strategy will coordinate with the Nevada visibility FIP by 

continuing to utilize the data collected by the IMPROVE program and will promote reasonable 

progress toward the national visibility goal. Under Nevada’s visibility FIP, Southern California 

Edison’s Mohave Generating Station1

 is required to meet certain emission control and limitation 

requirements for SO2; emission control and opacity requirements for PM; and emission controls 

for NOx. Under this regional haze (RH) SIP, the Mohave Generating Station is subject to Best 

Available Retrofit Technology (BART). The BART requirements result in substantially greater 

reductions of SO2 and PM10 emissions than the expected reductions from the visibility FIP. NOx

emissions are also expected to decrease as a result of BART when compared to the visibility FIP. 

Chapter Five includes a discussion of the BART process for the Mohave Generating Station. 

8.4 ASSOCIATED REGIONAL HAZE MONITORING STRATEGY 

REQUIREMENTS 

Other associated monitoring strategy components, as required by 40 CFR 51.308(d)(4)(i-vi) for 

Nevada’s SIP commitment, are presented below. The RHR requirement is shown below in 

italics, followed by Nevada’s response. 

The implementation plan must also provide for the following: 

(i) The establishment of any additional monitoring sites or equipment needed to assess 

whether reasonable progress goals to address regional haze for all mandatory Class I 

Federal areas within the State are being achieved. 

Sufficient funding for a complete and representative monitoring network within the 

IMPROVE program is supported by the USEPA. The IMPROVE site representing 

Nevada’s Class I area at the Jarbidge WA is considered to be sufficiently representative 

to support a determination of reasonable progress for the Jarbidge WA. 

 

1

 On June 10, 2009, the owners of the Mohave Generating Station, including Southern California Edison (SCE), 

announced the decision to decommission the station and remove the generating facility from the site. The SCE news 

release states that in 2010, the plant’s generating equipment will be removed and its operating permits terminated 

(http://www.edison.com/pressroom/pr.asp?bu=sce&year=2009&id=7234). 
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(ii) Procedures by which monitoring data and other information are used in determining the 

contribution of emissions from within the State to regional haze visibility impairment at 

mandatory Class I areas both within and outside the State. 

Visibility monitoring data is presently processed and maintained through the coordination 

of the IMPROVE program. Nevada expects the IMPROVE program monitoring 

operation and data collection to continue, with the fundamental assumption that network 

data collection operations will not change, or if changed, will remain directly comparable 

to those operated by the IMPROVE program during the 2000 through 2004 RHR baseline 

period. 

Generally, the Western Regional Air Partnership (WRAP) has analyzed, reduced and 

provided information on relative contributions to visibility impairment. Nevada has and 

will continue to use data reported by the IMPROVE program as input into the regional 

technical support analysis tool found at the Visibility Information Exchange Web System 

(VIEWS) and WRAP’s Technical Support System (TSS), as well as other analysis tools 

and efforts sponsored by the WRAP. The state will continue to participate in the regional 

analysis activities of the WRAP to collectively assess and verify the progress toward 

reasonable progress goals, as the RHR is implemented. If the technical support service 

that the WRAP has provided for this SIP is not available in the future, Nevada is 

uncertain how it would fulfill this requirement. Nevada does not have the resources to 

replace the functions that the WRAP has provided in support of the first planning period 

for the RH SIP. 

Evaluation activities, using the technical support provided by the WRAP as long as 

possible, will occur no less than every five years in association with 5-year progress 

reports and 10-year SIP revisions. 

(iii)For a State with no mandatory Class I Federal areas, procedures by which monitoring 

data and other information are used in determining the contribution of emissions from 

within the State to regional haze visibility impairment at mandatory Class I Federal 

areas in other States. 

Because Nevada has a mandatory Class I Federal area (Jarbidge WA), this requirement is 

addressed in paragraph (ii) above. 

(iv)The implementation plan must provide for the reporting of all visibility monitoring data 

to the Administrator at least annually for each mandatory Class I Federal area in the 

State. To the extent possible, the State should report visibility monitoring data 

electronically. 

Visibility monitoring data is available to the public, states and the USEPA in an electronic 

format at the following websites: IMPROVE (http://vista.cira.colostate.edu/improve/) and 

VIEWS (http://vista.cira.colostate.edu/views/). Nevada will depend on the continued routine 

timely reporting of monitoring data by these programs. 
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(v) A statewide inventory of emissions of pollutants that are reasonably anticipated to cause 

or contribute to visibility impairment in any mandatory Class I Federal area. The 

inventory must include emissions for a baseline year, emissions for the most recent year 

for which data are available, and estimates of future projected emissions. The State must 

also include a commitment to update the inventory periodically. 

With the support of the WRAP, Nevada has prepared a statewide inventory of emissions 

that can reasonably be expected to cause or contribute to visibility impairment in 

mandatory Class I areas. Chapter Three of this SIP summarizes the emissions by 

pollutant and source category. Nevada commits to updating its statewide emissions 

inventory periodically. The inventory updates will be used for state tracking of emission 

changes, determining trends and providing input into the WRAP’s evaluation of whether 

reasonable progress goals are being achieved, as well as other regional analyses. 

Nevada will depend upon and participate in additional periodic collective emissions 

inventory efforts by the WRAP. Further, the state will continue to depend on and use the 

capabilities of the WRAP-sponsored Regional Modeling Center to simulate the air 

quality impacts of emissions for haze planning purposes. If the technical support service 

that the WRAP has provided for this SIP is not available in the future, Nevada is 

uncertain how it would fulfill the requirement for estimates of future projected emissions. 

(vi)Other elements, including reporting, recordkeeping, and other measures, necessary to 

assess and report on visibility. 

Nevada will track data related to those sources for which the state has regulatory 

authority, and will depend on the IMPROVE program and WRAP-sponsored collection 

and analysis efforts and data support systems to assess and report on visibility. 

8.5 OVERVIEW OF IMPROVE SITE AT THE JARBIDGE WILDERNESS AREA 

The Jarbidge WA, described in Chapter One, is the only mandatory Class I area requiring 

visibility monitoring within Nevada. The IMPROVE monitoring site for the Jarbidge WA is 

located in the Humboldt National Forest in northeastern Nevada, approximately one kilometer 

north of the city of Jarbidge in the Jarbidge River drainage. The monitoring site has been 

maintained and operated by the U.S. Forest Service since 1986. As indicated previously, 

monitoring data may be obtained from the VIEWS and IMPROVE websites, as well as the 

WRAP TSS website. 

8.6 COMMITMENT TO FUTURE MONITORING 

Nevada is committed to continue using the IMPROVE monitoring data. If economic challenges 

are faced by the IMPROVE monitoring program, Nevada commits to working with federal 

agencies as a team to try to resolve the situation. Also, the state commits to continue developing 

updated emission inventory data to allow for tracking emission increases or decreases as related 

to regional haze, as funding and resources allow. Nevada updates its point source emission 
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inventory for major sources every year as required by USEPA. In addition, Nevada updates its 

entire emission inventory every three years (all point sources, area sources and mobile sources) 

as required by USEPA for the National Emission Inventory. Information collected will be made 

available on a periodic basis. As part of the periodic RH SIP revision discussed in Chapter 9, 

Nevada will re-evaluate the adequacy of the existing monitoring strategy.