(a) Permitted Uses. The following uses are permitted:
(1) Any use permitted in the M-2 District.
(2) Production, processing, cleaning, servicing, testing and repair, including the following uses and manufacturing of the following products:
A. Automobile wrecking.
B. Asphalt and asphalt products.
C. Chemicals, including acetylene, aniline dyes, ammonia, carbide, caustic soda, cellulose, chlorine, carbonblack, boneblack, cleaning and polishing preparations, creosote, exterminating agents, hydrogen, oxygen, industrial alcohol, nitrating of cotton or other materials, nitrates (manufactured and natural) of an explosive nature, potash, plastic materials, synthetic resins, pyroxylin, rayon yarn, hydrochloric, picric and sulphuric acids and derivatives.
D. Coal, coke and tar products, including gas manufacturing.
E. Electric central station, power and steam-generating plants.
F. Explosives, when not prohibited by other ordinances.
G. Fertilizers.
H. Film, photographic.
I. Flour, feed and grain, milling and processing.
J. Gelatin, glue and size, animal.
K. Incineration or reduction of garbage, offal and dead animals.
L. Linoleum and oil cloth.
M. Magnesium foundries.
N. Matches.
O. Metal and metal ores (except precious and raw metals), reduction, refining, smelting and alloying.
P. Paint, lacquer, shellac, varnishes, linseed oil and turpentine.
Q. Petroleum products, refining, such as gasoline, kerosene, naphtha, lubricating oil and liquefied petroleum gases.
R. Ready-mix cement plants.
S. Rubber (natural or synthetic).
T. Soaps, including fat and oil rendering.
U. Starch.
V. Stock yards, slaughterhouses and abattoirs.
W. Wood, coal and bones, distillation.
X. Wood pulp and fiber, reduction and processing, including paper mill operations.
Y. Any other production, processing, cleaning, servicing, testing and repair which conforms with the performance standards established hereinafter for the M-3 District.
(3) Storage, including the following uses and materials or products:
A. Goods used in or produced by manufacturing activities permitted in this district.
B. Dumps and slag piles.
C. Explosives.
D. Grain.
E. Manure, peat and topsoil.
F. Petroleum and petroleum products.
(4) Miscellaneous uses, as follows: Railroad freight terminals, motor freight terminals, railroad switching and classification yards, repair shops and roundhouses.
(b) Special Uses. The following uses may be allowed by special use permit:
(1) Any use which may be allowed as a special use in the M-2 District, unless already permitted in this district.
(2) Areas for the dumping or disposal of garbage, refuse or trash.
(c) Conditions of Use. Permitted uses are subject to the following conditions:
(1) All production, processing, cleaning, servicing, testing and repair or storage of goods, materials or products shall conform to the performance standards set forth below.
(2) Within 150 feet of a residence district, all business, production, processing, servicing and storage shall take place or be within completely enclosed buildings or structures, unless otherwise specified. Off-street parking and off-street loading facilities may be unenclosed, except for such screening and improvements as may be required under the provisions of Chapter 1262.
(d) Yard Areas. All yard areas shall be the same as required in the M-1 Limited Manufacturing District.
(e) Maximum Floor Area Ratio. The maximum floor area ratio shall be 3.0.
(g) Performance Standards. Any use established hereafter in the M-3 District shall be so operated as to comply with the performance standards set forth as follows:
(1) Noise. The performance standards governing noise in the M-1 District shall apply.
(2) Smoke and particulate matter.
A. No stack shall emit more than thirty smoke units during any one hour, nor shall smoke of a density in excess of Ringelmann No. 2 be emitted, provided that during fire cleaning periods, each stack may emit four minutes of smoke of a density of Ringelmann No. 3, and eight minutes of smoke of a density of Ringelmann No. 2, and during soot blowing periods, eight minutes of smoke of a density of Ringelmann No. 2.
B. No emission of smoke or particulate matter shall exceed a density of Ringelmann No. 3, except for a plume consisting entirely of condensed steam. For the purpose of grading the density of emission, the Ringelmann Chart published and used by the United States Bureau of Mines shall be employed.
C. The rate of emission of particulate matter from all sources within the boundaries of any lot shall not exceed a net figure of eight pounds per acre of lot area during any one hour.
D. Dust and other forms of air pollution borne by the wind, from such sources as storage areas, yards, roads and so forth, within lot boundaries, shall be kept to a minimum by appropriate landscaping, paving, oiling or other acceptable means.
E. In addition to the performance standards specified herein, the emission of smoke or particulate matter in such manner or quantity as to be detrimental to or endanger the public health, safety, comfort or welfare is hereby declared to be a public nuisance.
(3) Odorous matter. The emission of odorous matter from any property in such concentrations as to create a public nuisance or hazard beyond the boundaries of said property is prohibited.
(4) Vibration. Any process or equipment which produces intense earth-shaking vibrations, such as are created by heavy drop forges or heavy hydraulic surges, shall be set back at least 500 feet from the boundary of any residence, business, M-1 or M-2 District, unless such process or equipment is so controlled as to prevent the transmission beyond the said district boundary of earth-shaking vibrations perceptible without the aid of instruments. However, in no case shall such vibrations be allowed to create a public nuisance or hazard beyond the property line.
(5) Toxic or noxious matter. No use on any property shall discharge across the boundaries of said property toxic or noxious matter in such concentrations as to be detrimental to or endanger the public health, safety, comfort or welfare, or cause injury or damage to other property or business.
(6) Fire and explosive hazards. Fire and explosive hazards shall be controlled as follows:
A. Activities involving the storage or manufacture of materials or products which decompose by detonation are not permitted in the M-3 District, unless licensed by the City. However, in no case shall such materials or products be stored or manufactured within 200 feet of the boundary of any other district, unless otherwise authorized.
B. The storage, utilization or manufacture of materials or products ranging from incombustible to fast burning, as determined by the Zoning Administrator, or which produce flammable or explosive vapors or gases under ordinary weather temperature, is permitted. However, within 600 feet of the boundary of any other zoning district, the storage, utilization or manufacture of materials or products which produce flammable or explosive vapors or gases under ordinary weather temperature is not permitted, with the exception of the following, which are permitted within such 600 feet:
1. Materials required for emergency or standby equipment;
2. Materials used in secondary processes which are auxiliary to a principal operation, such as paint-spraying of finished products;
3. Flammable liquids and oils stored, sold and used in connection with the operation of an automobile service station and customarily required or used in such operation.
(1977 Code § 73-903)