5 Colo. Code Regs. § 1001-18-III
This Statement of Basis, Specific Authority, and Purpose complies with the requirements of the Administrative Procedures Act, section 24-4-103 C.R.S. and the Colorado Air Pollution Prevention and Control Act, section 25-7-110.5, C.R.S.
Basis
The "Colorado State Implementation Plan (SIP) for Particulate Matter (PM-10); Denver Metropolitan Nonattainment Area Element" signed into law on May 31, 1995 and subsequently approved by the U.S. Environmental Protection Agency includes in Chapter Xl.B.3.d the primary PM-10 emissions budget for mobile sources in the metro area.
As amended by § 25-7-105(1) (a) (III) , C.R.S. (1998), the metro area's mobile source PM-10 emissions budget for the purposes of federal transportation conformity is 54 tons per day from 1998- 2005 and 60 tons per day in 2006 and beyond.
Currently, in order to demonstrate conformity of regional transportation plans with the established mobile source emissions budgets for the area, the Denver Regional Council of Governments (DRCOG) obtains letters of commitment from city, county, and state agencies to reduce PM-10 emissions through improved street sanding and sweeping programs that go beyond what is currently required by Regulation 16. The emissions reduction achieved through this proposed "state-only" revision to Regulation 16 can be utilized for conformity purposes and will eliminate the need for DRCOG to seek commitment letters in the future.
Also, the provisions of section 25-7-105(1) (a) (III) include a 44 ton per day mobile source emissions budget which applies exclusively under reserved state authority pursuant to the provisions of C.R.S. 25-7-105(1). Section 25-7-105(1) (a) (III) also states that: "Any entity with authority to adopt a transportation plan required under section 43-1-1103, C.R.S., shall consider any mobile source emissions budgets in effect under this article in the development of transportation improvement programs for federal purposes." This includes consideration of the 44 ton per day mobile source emissions budget established under state law in Section V.C.4 of the Colorado Ambient Air Quality Standards Regulation.
As part of the development of the metro area's first comprehensive, long-range air quality plan, called the Blueprint for Clean Air, the Regional Air Quality Council (RAQC), evaluated the costs, benefits, and feasibility of achieving a 44 ton per day mobile source emissions budget as a state-only requirement. The modifications to Regulation 16 proposed in this action will implement the RAQC's final recommendation in the Blueprint for Clean air which, based on current data, will maintain mobile source PM-10 emissions in the budget area at no more than 45 tons per day through 2020.
Maintaining mobile source PM-10 emissions at 45 tons per day through 2020 will ensure the region stays in compliance with EPA's health-based standard for PM-10. Additionally, the emission reductions achieved through this regulatory modification will reduce fine particulate (PM-2.5) levels, providing a margin of safety against future violations of EPA's new standard for this pollutant.
Authority
General and specific authority for revising Air Quality Regulations is contained in the Colorado Air Pollution Control Act, Section 25-7-102, 25-7-109, 25-7-109(1), and 25-7-109(2) (a&b).
Purpose
The purpose of this regulatory modification is to prevent significant increases in mobile source PM-10 emissions in the metro Denver non-attainment area as the number of vehicle miles traveled continues to grow in the future. Adopting this rule as a state-only requirement means that it will not modify the existing State Implementation Plan, nor will these requirements be federally enforceable. However, the emission reductions achieved through implementation of the regulation will provide the region with a margin of safety against future violations of the National Ambient Air Quality Standards for PM-10 and PM-2.5.
The emission reductions proposed in this regulatory modification are already being achieved by most state and local agencies in the area. This state-only regulation will ensure that the emission reductions currently being achieved will be maintained into the future.
Findings
The Air Quality Control Commission makes the following findings pursuant to C.R.S. Section 25-7-110.8.
First, the rule revision is based on reasonably available, validated, reviewed and sound scientific methodologies. The uncontrolled emissions estimates and emissions budgets developed by the APCD are based on published EPA guidance. Maintenance levels of emissions are supported by SIP modeling performed in accordance with published EPA guidance. Data on alternative materials and the sand fraction of paved road dust are based on manufacturer's studies and local research conducted by the Colorado Department of Transportation and are acceptable to EPA. Efficiencies used for sweeping equipment are based on EPA guidance. Provisions have been included to allow consideration of additional information in the future which could allow for the achievement of the required reductions at reduced costs.
Second, the emissions reductions required by the revision will maintain the metro area at an emissions level through 2020 that will ensure compliance with the PM-10 NAAQS as demonstrated by SIP modeling and control the growth of PM-10 emissions.
Third, the emissions reduction is cost effective and allows for flexibility of choice of control strategies to achieve the requirement. It is also equitable and fair in that all entities are required to achieve the same overall reduction, and it makes provisions for the foothills areas which are already at the limit of safely achievable and cost effective reductions.
Fourth, the emissions reduction is reasonably achievable in that most entities are presently achieving reductions greater than required. This proposal received approval from many of the effected parties who participated in the RAQC's Street Sanding Subcommittee as part of the Blueprint for Clean Air. This measure also was recommended by the full RAQC when it formally adopted the Blueprint on January 7, 1999.
Federal Requirements
There are no federal requirements for this revision at this time.
Adopted: April 19, 2001
The amendments to the Regulation No. 16 are a component of the maintenance plan and redesignation request also adopted by the Commission on April 19, 2001 to redesignate the area as attainment for particulate matter less than ten microns in diameter (PM10).
The April 19, 2001 revisions to the regulations do three things. First, the revisions make federally enforceable the existing state-only requirements adopted by the Commission on May 20, 1999. The Commission adopted the state-only requirements in May 1999, which a require a 20% to 30% reduction in emissions from wintertime street sand and paved road dust throughout the area, to keep emissions from exceeding the state-only emissions budget then in effect. According to the Division's air quality models, the measures will be necessary to maintain the PM10 NAAQS and, therefore, must be made part of the federally-enforceable SIP.
Second, the revisions require further reductions in road dust emissions in the central Denver area, effective October 1, 2001. The revisions require emissions to be reduced by 50% to 72% from an established baseline.
Third, the revisions reorganize and simplify the regulations by describing all requisite emission reductions in terms of 1989 data.
Statutory Authority
General and specific authority for revising Air Quality Regulations is contained in the Colorado Air Pollution Control Act, § § 25-7-105(1)(a)(I), 25-7-107 (2.5), 25-7-109(1), (2)(a) and (2)(b).
Federal Requirements
The provisions adopted by the Commission do not exceed the federal requirements. 42 USC 7505a(a) requires the maintenance plan to include control measures as may be necessary to ensure maintenance of the NAAQS for at least ten years following redesignation. The revisions adopted by the Commission are necessary to demonstrate such maintenance of the NAAQS.
Findings
The Air Quality Control Commission makes the following findings pursuant to § 25-7-110.8, C.R.S.
Maintenance levels of emissions are supported by SIP modeling performed in accordance with published EPA guidance. Data on alternative materials and the sand fraction of paved road dust are based on manufacturer's studies and local research conducted by the Colorado Department of Transportation and are acceptable to EPA. Efficiencies used for sweeping equipment are based on EPA guidance and testing performed in Colorado. Provisions have been included to allow consideration of additional information in the future which could allow for the achievement of the required reductions at reduced costs. The Commission believes the EPA-approved models and guidance documents are inaccurate, but federal rules require the State to use such models and guidance to demonstrate the adequacy of the maintenance plan. Thus, the rule revisions are based on the only methodology authorized for use by federal law. All methodologies and information made available by interested parties have been considered.
The record reflects that reduced use of sand on paved roadways, and the clean-up of sanding material once applied, reduces ambient concentrations of PM10 in the ambient air. Thus, evidence in the record supports the finding that the rule will result in a demonstrable reduction in air pollution.
5 CCR 1001-18-III