25 Pa. Code § 250.604 - Fate and transport modeling requirements for exposure assessments
(a) A person may
use the soil-to-groundwater model in §
250.308(a)(2)
(relating to soil to groundwater pathway numeric values) to estimate
site-specific, soil-to-groundwater leaching potential for organic contaminants
if the following conditions are met:
(1)
Site-specific values of water-filled soil porosity, dry soil bulk density,
dilution factors (DF) and fraction organic carbon in soil beneath the source of
contamination (that is, not from top soil) are appropriately justified and the
person provides supporting data to the Department.
(2) Koc values as provided in §
250.308(a)(2) are
used or site-specific values which are appropriately justified are used and the
person provides supporting data to the Department.
(3) There is no identified separate phase
liquid contamination at the site.
(4) Other processes such as colloidal
transport or transport by means of dissolved organic matter (DOM) are not
significant at the site.
(5) The
application of the soil-to-groundwater model shall meet the most current EPA or
ASTM quality assurance/quality control criteria approved by the
Department.
(b) Except
for the soil-to-groundwater model in §
250.308(a)(2), a
person planning to use other fate and transport models and methods to estimate
exposure concentrations and to develop site-specific standards shall use
appropriate models or methods approved by the Department. The application of
groundwater models shall meet the most current EPA or ASTM quality
assurance/quality control criteria approved by the Department.
State regulations are updated quarterly; we currently have two versions available. Below is a comparison between our most recent version and the prior quarterly release. More comparison features will be added as we have more versions to compare.
No prior version found.