2018-16801. Documentation Supporting the Proposal of the Orange County North Basin Site; Addendum Availability

AGENCY:

Environmental Protection Agency (EPA).

ACTION:

Proposed rule; notice of data availability.

SUMMARY:

This notice provides an opportunity to comment on additional reference documentation for the Orange County North Basin site in Orange County, California. The site was proposed to the National Priorities List (NPL) on January 18, 2018.

DATES:

Comments must be submitted (postmarked) on or before September 12, 2018.

ADDRESSES:

Submit your comments, identified by docket number EPA-HQ-OLEM-2017-0603, at https://www.regulations.gov. Follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from Regulations.gov. The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission (i.e., on the web, cloud, or other file sharing system). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit https://www.epa.gov/​dockets/​commenting-epa-dockets.

To send a comment via the United States Postal Service, use the following address: U.S. Environmental Protection Agency, EPA Superfund Docket Center, Mailcode 28221T, 1200 Pennsylvania Avenue NW, Washington, DC 20460. Use the Docket Center address below if you are using express mail, commercial delivery, hand delivery or courier. Delivery verification signatures will be available only during regular business hours: EPA Superfund Docket Center, WJC West Building, Room 3334, 1301 Constitution Avenue NW, Washington, DC 20004.

FOR FURTHER INFORMATION CONTACT:

Jennifer Wendel, phone: [phone], email: [e-mail], Site Assessment and Remedy Decisions Branch, Assessment and Remediation Division, Office of Superfund Remediation and Technology Innovation (Mail Code 5204P), U.S. Environmental Protection Agency, 1200 Pennsylvania Avenue NW, Washington, DC 20460.

SUPPLEMENTARY INFORMATION:

The site was proposed to the National Priorities List (NPL) on January 18, 2018 (83 FR 2576).

Site Geological Information

One commenter questioned the EPA's use of a reference in the HRS documentation record (HRS Reference 110—the 3DVA Technical Memorandum) to support aquifer interconnection and contaminant migration. EPA notes that the reference in question is a model, and analysis, of the hydrology and geology in the vicinity of the Orange County North Basin site. The commenter stated that the EPA cites to HRS Reference 110 and presents conclusions in the HRS documentation record based on the model in the reference that used well borehole and lithology data that was not available to the public to review to confirm the reliability of the reference.

The EPA has examined this issue and has decided to provide the relevant documentation used to develop the content presented in the reference. This information includes well logs and lithology reports for the wells which were used to produce HRS Reference 110—the 3DVA Technical Memorandum. This data will be included as one reference to the HRS documentation record and the EPA is providing this additional document for public review and comment. This document is available at the Regional office in San Francisco, CA. Anyone wishing to comment on the information in the reference or the impact this data may have on the HRS score for the proposed Orange County North Basin site should do so within the next 30 calendar days (see DATES section at the beginning of this notice). Additional comments will not be accepted on other HRS scoring issues which could have appropriately been raised during the original comment period and are not based on information provided in these additional references.

Comments should be submitted pursuant to instructions in the ADDRESSEES section of this notice; they may be submitted electronically, by mail or by express mail. The docket number for this site is EPA-HQ-OLEM-2017-0603 and should be identified in any correspondence/electronic submission.

Dated: July 16, 2018.

James E. Woolford,

Director, Office of Superfund Remediation and Technology Innovation.