The following information applies to sulfur dioxide (SO2) allowances issued under the Acid Rain Program. Similar information for NOx allowances is not yet available.
For a brief description of how EPA allocated allowances under the Acid Rain Program, see the SO2 Allowances Fact Sheet.
Phase II Allowances
As required by the Clean Air Act Amendments of 1990, this rule revises the final allowance allocations published in March 1993 for affected utility units under the Acid Rain Program. It explains the process by which EPA allocated allowances. The allocations themselves are available as a compressed Excel file that includes boiler/generator-level, boiler-level, and State-level allocations (Zip, 678 K).
Supporting Documentation (including NADB):
- Technical Documentation for the 1998 Reallocation of Allowances (PDF) (50 pp., 299 K) (The technical support document for allocation calculations.) A separate file contains the appendices (PDF), (71 pp., 299 K) including SAS code and programmer instruction.
- Technical Support Documentation for the underlying National Allowance Data Base (NADB) Version 2.2 (PDF) (105 pp., 272 K)
- National Allowance Database version 3.2: boiler and generator level data used for the 1998 allowance re-allocation. In addition to SO2-related data, the database includes a great deal of utility plant information. Version 2.2 was the first version on which the original allowance allocations were based.