Jump to main content.

Risk Assessment
Risk Assessment and Federal Guidance Programs:  


Note: EPA no longer updates this information, but it may be useful as a reference or resource.

Risk Assessment

PRESTO(Prediction of Radiological Effects Due to Shallow Trench Operations) is a computer model for evaluating radiation exposure from contaminated soil layers, including waste disposal, soil cleanup, agricultural land application, and land reclamation.

On this page:

Download Software, Instructions, and Documentation

The table below allows you to download both the software and the user guides for Version 4.2 of PRESTO-EPA-CPG /POP Operation System. The PRESTO-EPA-CPG/POP Operation System contains a family of PRESTO multimedia models:

These documents are continuously being improved and we encourage you to comment on the effectiveness and applicability of this operation system.

Top of page


These models are intended to support the development of EPA's environmental standards and criteria. The initial models, published in 1987, were developed for a mainframe computer. Subsequent versions were modified to operate on a personal computer in a DOS environment.

The current Version 4.2 of the PRESTO-EPA-CPG/POP Operation System combines these two systems and operates in a Windows environment. It also incorporates new features, including the addition of soil cleanup, agricultural land application, and land reclamation to the waste trench operation scenarios.

Top of page

Application Niche

The models are designed to calculate the maximum annual committed effective dose to a critical population group and cumulative fatal health effects and genetic effects to the general population in several scenarios:

  1. near surface disposal trench containing low-level radioactive waste and/or naturally occurring or accelerator produced radioactive material (NARM)
  2. residual radionuclides remaining in soil layers after cleanup
  3. agricultural land application of technologically enhanced naturally occurring radioactive materials (TENORM) waste
  4. stripped land reclamation with applied TENORM waste

The models simulate the transport of radionuclides in air, surface water, and groundwater pathways, and evaluate exposures through ingestion, inhalation, immersion and external exposure pathways.

Top of page

Regulatory Context

EPA has used the PRESTO-EPA-CPG/POP Operation Systems extensively to generate dose and risk estimates to support the following EPA rules and reports:

Top of page

Strengths and Limitations

To avoid overly conservative results, EPA employed the following approaches:

Theoretically, a one-dimensional model can produce a significant amount of error relative to a three dimensional model; however, the magnitude of this error depends largely on the conditions of the application. A recent study indicated that under normal applications, this relative error may range from zero to 10 percent for the PRESTO-EPA-CPG and virtually zero error for PRESTO-EPA-POP.

Top of page

Verification, Validation And Peer Review

RESTO-EPA-CPG and PRESTO-EPA-POP have been subjected to extensive quality assurance and peer reviews:

Source Inches/year
PRESTO analyses 13.8-17.7
USGS field data 14-17
NRC field data 14

Top of page

Hardware Requirements

Top of page


Local Navigation

Radiation Home

Jump to main content.