[Code of Federal Regulations]
[Title 40, Volume 24]
[Revised as of July 1, 2006]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR194.23]

[Page 47-48]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 194_CRITERIA FOR THE CERTIFICATION AND RE-CERTIFICATION OF THE WASTE 
ISOLATION PILOT PLANT'S COMPLIANCE WITH THE 40 CFR PART 191 DISPOSAL 
REGULATIONS--Table of Contents
 
         Subpart C_Compliance Certification and Re-certification
 
Sec. 194.23  Models and computer codes.

    (a) Any compliance application shall include:
    (1) A description of the conceptual models and scenario construction 
used to support any compliance application.
    (2) A description of plausible, alternative conceptual model(s) 
seriously considered but not used to support such application, and an 
explanation of the reason(s) why such model(s) was not deemed to 
accurately portray performance of the disposal system.
    (3) Documentation that:
    (i) Conceptual models and scenarios reasonably represent possible 
future states of the disposal system;
    (ii) Mathematical models incorporate equations and boundary 
conditions which reasonably represent the mathematical formulation of 
the conceptual models;
    (iii) Numerical models provide numerical schemes which enable the 
mathematical models to obtain stable solutions;
    (iv) Computer models accurately implement the numerical models; 
i.e., computer codes are free of coding errors and produce stable 
solutions;
    (v) Conceptual models have undergone peer review according to Sec. 
194.27.
    (b) Computer codes used to support any compliance application shall 
be documented in a manner that complies with the requirements of ASME 
NQA-2a-1990 addenda, part 2.7, to ASME NQA-2-1989 edition. 
(Incorporation by reference as specified in Sec. 194.5.)
    (c) Documentation of all models and computer codes included as part 
of any compliance application performance assessment calculation shall 
be provided. Such documentation shall include, but shall not be limited 
to:
    (1) Descriptions of the theoretical backgrounds of each model and 
the method of analysis or assessment;
    (2) General descriptions of the models; discussions of the limits of 
applicability of each model; detailed instructions for executing the 
computer codes, including hardware and software requirements, input and 
output formats with explanations of each input and output variable and 
parameter (e.g., parameter name and units); listings of input and output 
files from a sample computer run; and reports on code verification, 
benchmarking, validation, and quality assurance procedures;

[[Page 48]]

    (3) Detailed descriptions of the structure of computer codes and 
complete listings of the source codes;
    (4) Detailed descriptions of data collection procedures, sources of 
data, data reduction and analysis, and code input parameter development;
    (5) Any necessary licenses; and
    (6) An explanation of the manner in which models and computer codes 
incorporate the effects of parameter correlation.
    (d) The Administrator or the Administrator's authorized 
representative may verify the results of computer simulations used to 
support any compliance application by performing independent 
simulations. Data files, source codes, executable versions of computer 
software for each model, other material or information needed to permit 
the Administrator or the Administrator's authorized representative to 
perform independent simulations, and access to necessary hardware to 
perform such simulations, shall be provided within 30 calendar days of a 
request by the Administrator or the Administrator's authorized 
representative.