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SIP - ECOLOGY - 400 - 040 

173-400-040 GENERAL STANDARDS FOR MAXIMUM EMISSIONS.

All sources and emissions units are required to meet the emission standards of this 

chapter. Where an emission standard listed in another chapter is applicable to a 

specific emissions unit, such standard will take precedent over a general emission 

standard listed in this chapter. When two or more emissions units are connected to a 

common stack and the operator elects not to provide the means or facilities to sample 

emissions from the individual emissions units, and the relative contributions of the 

individual emissions units to the common discharge are not readily distinguishable, 

then the emissions of the common stack must meet the most restrictive standard of any 

of the connected emissions units. Further, all emissions units are required to use 

reasonably available control technology (RACT) which may be determined for some 

sources or source categories to be more stringent than the applicable emission 

limitations of any chapter of Title 173 WAC. Where current controls are determined to 

be less than RACT, ecology or the authority shall, as provided in section 8, chapter 

252, Laws of 1993, define RACT for each source or source category and issue a rule or 

regulatory order requiring the installation of RACT.

(1) Visible emissions. No person shall cause or permit the emission for more than three 

minutes, in any one hour, of an air contaminant from any emissions unit which at the 

emission point, or within a reasonable distance of the emission point, exceeds twenty 

percent opacity except:

(a) When the emissions occur due to soot blowing/grate cleaning and the operator 

can demonstrate that the emissions will not exceed twenty percent opacity for 

more than fifteen minutes in any eight consecutive hours. The intent of this 

provision is to permit the soot blowing and grate cleaning necessary to the 

operation of boiler facilities. This practice, except for testing and trouble 

shooting, is to be scheduled for the same approximate times each day and 

ecology or the authority be advised of the schedule.

(b) When the owner or operator of a source supplies valid data to show that the 

presence of uncombined water is the only reason for the opacity to exceed twenty 

percent.

(c) When two or more sources are connected to a common stack, ecology or the 

authority may allow or require the use of an alternate time period if it is more 

representative of normal operations.

(d) When an alternate opacity limit has been established per RCW 70.94.331 (2)

Region 10: the Pacific Northwest

Last updated on Saturday, March 12th, 2011.

URL: http://yosemite.epa.gov/r10/airpage.nsf/SIPs/ECOLOGY/SIPEcology

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(c).

(2) Fallout. No person shall cause or permit the emission of particulate matter from any 

source to be deposited beyond the property under direct control of the owner(s) or 

operator(s) of the source in sufficient quantity to interfere unreasonably with the use 

and enjoyment of the property upon which the material is deposited.

(3) Fugitive emissions. The owner or operator of any emissions unit engaging in 

materials handling, construction, demolition or any other operation which is a source 

of fugitive emission:

(a) If located in an attainment area and not impacting any nonattainment area, 

shall take reasonable precautions to prevent the release of air contaminants from 

the operation.

(b) If the emissions unit has been identified as a significant contributor to the 

nonattainment status of a designated nonattainment area, shall be required to use 

reasonable and available control methods, which shall include any necessary 

changes in technology, process, or other control strategies to control emissions of 

the contaminants for which nonattainment has been designated.

(4) Odors. Any person who shall cause or allow the generation of any odor from any 

source which may unreasonably interfere with any other property owner's use and 

enjoyment of his property must use recognized good practice and procedures to reduce 

these odors to a reasonable minimum.

(5) Emissions detrimental to persons or property. No person shall cause or permit the 

emission of any air contaminant from any source if it is detrimental to the health, 

safety, or welfare of any person, or causes damage to property or business.

(6) Sulfur dioxide.

No person shall cause or permit the emission of a gas containing sulfur dioxide from 

any emissions unit in excess of one thousand ppm of sulfur dioxide on a dry basis, 

corrected to seven percent oxygen for combustion sources, and based on the average of 

any period of sixty consecutive minutes, except:

When the owner or operator of an emissions unit supplies emission data and can 

demonstrate to ecology or the authority that there is no feasible method of reducing the 

concentration to less than one thousand ppm (on a dry basis, corrected to seven percent 

oxygen for combustion sources) and that the state and federal ambient air quality 

standards for sulfur dioxide will not be exceeded. In such cases, ecology or the 

authority may require specific ambient air monitoring stations be established, operated, 

and maintained by the owner or operator at mutually approved locations. All sampling 

results will be made available upon request and a monthly summary will be submitted 

to ecology or the authority.

(7) Concealment and masking. No person shall cause or permit the installation or use 

of any means which conceals or masks an emission of an air contaminant which would 

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otherwise violate any provisions of this chapter.

(8) Fugitive dust sources.

(a) The owner or operator of a source of fugitive dust shall take reasonable 

precautions to prevent fugitive dust from becoming airborne and shall maintain 

and operate the source to minimize emissions.

(b) The owner(s) or operator(s) of any existing source(s) of fugitive dust that has 

been identified as a significant contributor to a PM-10 nonattainment area shall 

be required to use reasonably available control technology to control emissions. 

Significance will be determined by the criteria found in WAC 173-400-113(3).

State adopted: 9/20/93; EPA effective: 6/2/95

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