Appendix A - Explanation of Standard Industrial Classification (SIC) Codes Regulated by the Industrial Storm Water Program
| Industry Type | SIC Code | Comments |
| Metal mining and milling | 10 | (a) |
| Coal mining | 12 | (a) |
| Oil and Gas Extraction | 13 | |
| Mining and quarrying of nonmetallic minerals except fuels | 14 | (a) |
| Food and kindred products | 20 | |
| Tobacco products | 21 | |
| Textile mill products | 22 | |
| Apparel and other finished products made from fabric and similar materials | 23 | |
| Lumber and wood products except furniture | 24 | |
| Furniture and fixtures | 25 | |
| Paper and allied products | 26 | |
| Printing, publishing, and allied products | 27 | |
| Chemicals and allied products | 28 | |
| Petroleum refining and related industries | 29 | |
| Rubber and miscellaneous plastics products | 30 | |
| Leather and leather products | 31 | |
| Stone, clay, glass and concrete products | 32 | |
| Primary metal industries | 33 | |
| Fabrication of metal products, except machinery and transportation equipment | 34 | |
| Industrial and commercial machinery and computer equipment | 35 | |
| Electronic and other electrical equipment and components, except compute equipment | 36 | |
| Transportation equipment | 37 | |
| Measuring analyzing, and controlling instruments; Photographic, medical, and optical goods; watches and clocks | 38 | |
| Miscellaneous manufacturing industries | 39 | |
| Railroad transportation | 40 | (b) |
| Local and suburban transit and interurban highway passenger transportation | 41 | (b) |
| Motor freight transportation and warehousing | 42 (except 4221, 4222, and 4225) | (b) |
| Farm product warehousing and storage Refrigerated warehousing and storage General warehousing and storage | 4221 4222 4225 | |
| US Postal facilities | 43 | (b) |
| Water transportation | 44 | (b) |
| Transportation by air | 45 | (b) |
| Motor vehicle parts, used | 5015 | |
| Scrap and waste materials | 5093 | |
| Petroleum bulk stations and terminals | 5171 | (b) |
Comments:
(a) For this SIC Code, a storm water permit is required only if runoff contacts overburden, raw material, intermediate products, finished products, byproducts or waste products located on the site of such operations.
(b) In this SIC Code, only facilities with vehicle maintenance (including vehicle rehabilitation, mechanical repairs, painting, fueling, and lubrication), equipment cleaning, or airport deicing need a storm water permit.