R18-2-520. Renumbered 

Historical Note

Adopted effective May 14, 1979 (Supp. 79-1). Amended effective October 2, 1979 (Supp. 79-5). 

Editorial correction, subsection (A), paragraph (1) (Supp. 80-2). Amended effective July 9, 1980 

(Supp. 80-4). Amended subsection (A) effective May 28, 1982 (Supp. 82-3). Amended 

subsection (A) effective September 22, 1983 (Supp. 83-5). Former Section R9-3-520 renumbered 

without change as Section R18-2-520 (Supp. 87-3). Amended effective September 26, 1990 

(Supp. 90-3). Renumbered to R18-2-720 effective November 15, 1993 (Supp. 93-4).

R18-2-720. Standards of Performance for Existing Lime Manufacturing Plants

A. The provisions of this Section are applicable to the following affected facilities used in the 

manufacture of lime: rotary lime kilns, vertical lime kilns, lime hydrators, and limestone 

crushing facilities. This Section is also applicable to limestone crushing equipment which 

exists apart from other lime manufacturing facilities.

B. No person shall cause, allow or permit the discharge of particulate matter into the atmosphere 

in any one hour from any lime manufacturing or limestone crushing facility in total quantities 

in excess of the amounts calculated by one of the following equations:

1. For process sources having a process weight rate of 60,000 pounds per hour (30 tons per 

hour) or less, the maximum allowable emissions shall be determined by the following 

equation:

E = 4.10P0.67

where:

E = the maximum allowable particulate emissions rate in pounds-mass per hour.

P = the process weight rate in tons-mass per hour.

2. For process sources having a process weight rate greater than 60,000 pounds per hour (30 

tons per hour), the maximum allowable emissions shall be determined by the following 

equation:

E = 55.0P0.11-40

where “E” and “P” are defined as indicated in subsection (B)(1).

C. Actual values shall be calculated from the applicable equations and rounded off to two decimal 

places.

D. For purposes of this Section, the total process weight from all similar units employing a similar 

type process shall be used in determining the maximum allowable emission of particulate 

matter.

E. Fugitive emissions from lime plants shall be controlled in accordance with R18-2-604 through 

R18-2-607.

F. The owner or operator subject to the provisions of this Section shall install, calibrate, maintain, 

and operate a continuous monitoring system, except as provided in subsection (G), to monitor 

and record the opacity of the gases discharged into the atmosphere from any rotary lime kiln. 

The span of this system shall be set at 70% opacity.
G. The owner or operator of any rotary lime kiln using a wet scrubbing emission control device 

subject to the provisions of this Section shall not be required to monitor the opacity of the gases 

discharged as required in subsection (F).

H. The test methods and procedures required by this Section are as follows:

1. The reference methods in 40 CFR 60, Appendix A, as incorporated by reference in Appendix 

2 of this Chapter, shall be used to determine compliance with this Section as follows:

a. Method 5 for the measurement of particulate matter,

b. Method 1 for sample and velocity traverses,

c. Method 2 for velocity and volumetric flow rate,

d. Method 3 for gas analysis,

e. Method 4 for stack gas moisture,

f. Method 9 for visible emissions.

2. For Method 5, the sampling time for each run shall be at least 60 minutes and the sampling 

rate shall be at least 0.85 dscm/hr (0.53 dscf/min), except that shorter sampling times, when 

necessitated by process variables or other factors, may be approved by the Director.

3. Because of the high moisture content of the exhaust gases from the hydrators, in the range 

of 40 to 85% by volume, the Method 5 sample train may be modified to include a calibrated 

orifice immediately following the sample nozzle when testing lime hydrators. In this 

configuration, the sampling rate necessary for maintaining isokinetic conditions can be 

directly related to exhaust gas velocity without a correction for moisture content. 

Historical Note

Section R18-2-720 renumbered from R18-2-520 and amended effective November 15, 1993 

(Supp. 93-4). Amended by final rulemaking at 15 A.A.R. 281, effective March 7, 2009 

(Supp. 09-1).