Quiero saber acerca de...

Federal Register / Vol. 86, No. 40 / Wednesday, March 3, 2021 / Rules and Regulations
childrens exposure and health effects information.
The three phases of the Fourth Regulatory Determination process are
1 the Data Availability Phase, 2 the Data Evaluation Phase and 3 the Regulatory Determination Assessment
Phase. The overall process is displayed in Exhibit 1.

The purpose of the first phase, the Data Availability Phase, is to screen out contaminants that clearly do not have sufficient data to support a regulatory determination. The Agency applies criteria to ensure that any contaminant that potentially has sufficient data to characterize the health effects and known or likely occurrence in drinking water will proceed to the Data Evaluation Phase, the second phase of the regulatory determination process.
From the 109 CCL 4 contaminants, the Agency identified 25 CCL 4
contaminants to further evaluate in the second phase. These are known as the short list.
During the second phase, the Agency evaluates the contaminants on the short list in greater depth and detail to identify those that have sufficient data or are expected to have sufficient data
within the timeframe allotted for the second phase for EPA to assess the three statutory criteria. As part of the second phase, the Agency specifically focuses its efforts on identifying those contaminants or contaminant groups that are occurring or have substantial likelihood to occur at levels and frequencies of public health concern, based on the best available peer reviewed data. If, during the first or second phase, the Agency finds that sufficient data are not available or not likely to be available to evaluate the three statutory criteria, then the contaminant is not considered a candidate for making a regulatory determination.
If sufficient data are available for a contaminant to characterize the potential health effects and known or likely occurrence in drinking water, the
contaminant is evaluated against the three statutory criteria in the Regulatory Determination Assessment Phase, which is the third phase of the process.
Of the 25 contaminants that were evaluated under Phase 2, 10 were designated for evaluation against the three statutory criteria in Phase 3.
Of the 10 CCL4 contaminants that were evaluated in Phase 3, the Agency did not make preliminary regulatory determinations for two contaminants 1,4-dioxane and 1,2,3trichloropropane; see Section IV of this document for discussion about these contaminants. Additionally, in Section IV of this document, EPA discusses continuing with its previous 2016
decision to defer a final determination for strontium a CCL3 contaminant for which the Agency made a preliminary positive determination in the third
VerDate Sep<11>2014

16:13 Mar 02, 2021

Jkt 253001

PO 00000

Frm 00018

Fmt 4700

Sfmt 4700

E:FRFM03MRR1.SGM

03MRR1

ER03MR21.101

jbell on DSKJLSW7X2PROD with RULES

12274