Document ID: EPA-HQ-SFUND-1991-0006-0002
Agency: epa
Document Type: Rule
Title: National Oil and Hazardous Substances Pollution Contingency Plan: Midvale Slag Superfund Site; National Priorities List; Deletion
Posted Date: 2015-02-05T05:00Z

[Federal Register Volume 80, Number 24 (Thursday, February 5, 2015)]
[Rules and Regulations]
[Pages 6458-6464]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: 2015-02326]

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ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 300

[EPA-HQ-SFUND-1991-0006; FRL-9922-55-Region 8]

National Oil and Hazardous Substances Pollution Contingency Plan 
National Priorities List: Deletion of the Midvale Slag Superfund Site

AGENCY: Environmental Protection Agency.

ACTION: Direct final rule.

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SUMMARY: The U.S. Environmental Protection Agency (EPA) Region 8 is 
publishing a direct final Notice of Deletion of the Midvale Slag 
Superfund Site (Site), located in Salt Lake County, Utah, from the 
National Priorities List (NPL). The NPL, promulgated pursuant to 
section 105 of the Comprehensive Environmental Response, Compensation, 
and Liability Act (CERCLA) of 1980, as amended, is an appendix of the 
National Oil and Hazardous Substances Pollution Contingency Plan (NCP). 
This direct final deletion is being published by EPA with the 
concurrence of the State of Utah, through the Utah Department of 
Environmental Quality (UDEQ), because EPA has determined that all 
appropriate response actions under CERCLA, other than operation, 
maintenance and five-year reviews of the Site, have been completed. 
However, this deletion does not preclude future actions under 
Superfund.

DATES: This direct final deletion is effective April 6, 2015 unless EPA 
receives adverse comments by March 9, 2015. If adverse comments are 
received, EPA will publish a timely withdrawal of the direct final 
deletion in the Federal Register informing the public that the deletion 
will not take effect.

ADDRESSES: Submit your comments, identified by Docket ID no. EPA-HQ-
SFUND-1991-0006, by one of the following methods: (1) http://www.regulations.gov: Follow on-line instructions for submitting 
comments. (2) Email: waterman.erna@epa.gov (3) Fax: 303-312-7151 (4) 
Mail: Erna Waterman, Remedial Project Manager, U.S. EPA, Region 8, Mail 
Code 8EPR-SR, 1595 Wynkoop Street, Denver, CO 80202-1129 (5) Hand 
delivery: US EPA, Region 8, 1595 Wynkoop Street, EPR-SR, Denver, CO 
80202-1129. Such deliveries are only accepted during EPA's normal hours 
of operation (9 a.m. to 5 p.m.), and special arrangements should be 
made for deliveries of boxed information.
    Instructions: Direct your comments to Docket ID no. EPA-HQ-SFUND-
1991-0006. EPA's policy is that all comments received will be included 
in the public docket without change and may be made available online at 
http://www.regulations.gov, including any personal information 
provided, unless the comment includes information claimed to be 
Confidential Business Information (CBI) or other information whose 
disclosure is restricted by statute. Do not submit information that you 
consider to be CBI or otherwise protected through http://www.regulations.gov or email. The http://www.regulations.gov Web site 
is an ``anonymous access'' system, which means EPA will not know your 
identity or contact information unless you provide it in the body of 
your comment. If you send an email comment directly to EPA without 
going through http://www.regulations.gov, your email

[[Page 6459]]

address will be automatically captured and included as part of the 
comment that is placed in the public docket and made available on the 
Internet. If you submit an electronic comment, EPA recommends that you 
include your name and other contact information in the body of your 
comment and with any disk or CD-ROM you submit. If EPA cannot read your 
comment due to technical difficulties and cannot contact you for 
clarification, EPA may not be able to consider your comment. Electronic 
files should avoid the use of special characters, any form of 
encryption, and be free of any defects or viruses.
    Docket: All documents in the docket are listed in the http://www.regulations.gov index. Although listed in the index, some 
information is not publicly available, e.g., CBI or other information 
whose disclosure is restricted by statute. Certain other material, such 
as copyrighted material, will be publicly available only in hard copy. 
Publicly available docket materials are available electronically at 
http://www.regulations.gov or in hard copy at Ruth Tyler Branch 
Library, 8041 South Wood, Midvale, UT 84047; Phone: (801-944-7641); 
Hours: M-Th: 9 a.m.-9 p.m.; Fri-Sat: 9:00 a.m.-5:30 p.m.

FOR FURTHER INFORMATION CONTACT: Erna Waterman, Remedial Project 
Manager, U.S. EPA Region 8, Mail code: 8EPR-SR, 1595 Wynkoop Street, 
Denver, CO 80202-1129; Phone: (303) 312-6762; Email: 
waterman.erna@epa.gov. You may contact Erna to request a hard copy of 
publicly available docket materials.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Introduction
II. NPL Deletion Criteria
III. Deletion Procedures
IV. Basis for Site Deletion
V. Deletion Action

I. Introduction

    EPA Region 8 is publishing this direct final Notice of Deletion of 
the Midvale Slag Superfund Site from the National Priorities List. The 
NPL constitutes Appendix B of 40 CFR part 300, which is the National 
Oil and Hazardous Substances Pollution Contingency Plan (NCP), which 
EPA promulgated pursuant to Section 105 of the Comprehensive 
Environmental Response, Compensation, and Liability Act (CERCLA) of 
1980, as amended. EPA maintains the NPL as the list of sites that 
appear to present a significant risk to public health, welfare, or the 
environment. Sites on the NPL may be the subject of remedial actions 
financed by the Hazardous Substance Superfund (Fund). As described in 
40 CFR 300.425(e)(3) of the NCP, sites deleted from the NPL remain 
eligible for Fund-financed remedial action if future conditions warrant 
such actions.
    Section II of this document explains the criteria for deleting 
sites from the NPL. Section III discusses procedures that EPA is using 
for this action. Section IV discusses the Midvale Slag Superfund Site 
and demonstrates how it meets the deletion criteria. Section V 
discusses EPA's action to delete the Site from the NPL unless adverse 
comments are received during the public comment period.

II. NPL Deletion Criteria

    The NCP establishes the criteria that EPA uses to delete sites from 
the NPL. In accordance with 40 CFR 300.425(e), sites may be deleted 
from the NPL where no further response is appropriate. In making such a 
determination pursuant to 40 CFR 300.425(e), EPA will consider, in 
consultation with the State, whether any of the following criteria have 
been met:
    i. Responsible parties or other persons have implemented all 
appropriate response actions required;
    ii. all appropriate Fund-financed response under CERCLA has been 
implemented, and no further response action by responsible parties is 
appropriate; or
    iii. the remedial investigation has shown that the release poses no 
significant threat to public health or the environment and, therefore, 
the taking of remedial measures is not appropriate.
    Pursuant to CERCLA section 121(c) and the NCP, EPA conducts five-
year reviews to ensure the continued protectiveness of remedial actions 
where hazardous substances, pollutants, or contaminants remain at a 
site above levels that allow for unlimited use and unrestricted 
exposure. EPA conducts such five-year reviews even if a site is deleted 
from the NPL. EPA may initiate further action to ensure continued 
protectiveness at a deleted site if new information becomes available 
that indicates it is appropriate. Whenever there is a significant 
release from a site deleted from the NPL, the deleted site may be 
restored to the NPL without application of the hazard ranking system.

III. Deletion Procedures

    The following procedures apply to the deletion of the Site.
    (1) EPA consulted with the State of Utah prior to developing this 
direct final Notice of Deletion and the Notice of Intent to Delete the 
Site co-published today in the ``Proposed Rules'' section of the 
Federal Register.
    (2) EPA has provided the State 30 working days for review of this 
direct final Notice of Deletion and the parallel Notice of Intent to 
Delete prior to their publication today, and the State, through UDEQ, 
has concurred on the deletion of the Site from the NPL.
    (3) Concurrently with the publication of this direct final Notice 
of Deletion, a notice of the availability of the parallel Notice of 
Intent to Delete is being published in a major local newspaper, the 
Salt Lake Tribune. The newspaper notice announces the 30-day public 
comment period concerning the Notice of Intent to Delete the Site from 
the NPL.
    (4) The EPA placed copies of documents supporting the proposed 
deletion in the deletion docket and made these items available for 
public inspection and copying at the Site information repositories 
identified above.
    (5) If adverse comments are received within the 30-day public 
comment period on this deletion action, EPA will publish a timely 
notice of withdrawal of this direct final Notice of Deletion before its 
effective date and will prepare a response to comments and continue 
with the deletion process on the basis of the Notice of Intent to 
Delete and the comments already received.
    Deletion of a site from the NPL does not itself create, alter, or 
revoke any individual's rights or obligations. Deletion of a site from 
the NPL does not in any way alter EPA's right to take enforcement 
actions, as appropriate. The NPL is designed primarily for 
informational purposes and to assist EPA management. Section 
300.425(e)(3) of the NCP states that the deletion of a site from the 
NPL does not preclude eligibility for further response actions, should 
future conditions warrant such actions.

IV. Basis for Site Deletion

    The following information provides EPA's rationale for deleting the 
Site from the NPL.

Site Background and History

    The 446-acre Midvale Slag Superfund Site (UTD08134277) is located 
12 miles south of Salt Lake City in the city of Midvale, with a small 
portion extending into the adjacent city of Murray. The Site is a 
former smelting facility on the Jordan River. Five separate smelters 
were located on or near the Site from 1871 to 1958. An adjacent mill 
continued operating until 1971. The smelters treated ores from Bingham 
Canyon and other mines. Investigations

[[Page 6460]]

at the Site showed that groundwater and soils were contaminated with 
heavy metals. Lead smelting was the dominant industrial activity at the 
Site; lead and arsenic were the primary products associated with ore 
processing. At times copper, gold, silver, and other metals were also 
produced at the Site. Ore processing and disposal of waste products on 
the site have resulted in contamination of soils and groundwater at the 
Site.
    The EPA proposed the Midvale Slag Superfund Site on the National 
Priorities List (NPL) on June 10, 1986 and finalized listing of the 
site on February 11, 1991 (51 FR 21099 and 56 FR 5598). The Site was 
divided into two operable units (OUs). OU1 is the northern 266 acres of 
the site. OU2 is the remaining 180 acres to the south. The dividing 
boundary that runs through the Site between OU1 and OU2 is 7200 South 
Parkway and Jordan River Boulevard.
    OU1 includes a mobile home park, an abandoned waste water treatment 
plant with lagoons, and jurisdictional wetlands. Wastes have been 
present on the Site for many years and, in some locations, groundwater 
is in direct contact with visible slag without appreciable effects on 
groundwater. Concentrations of contaminants of concern (COCs) in OU1 
groundwater are generally below federal maximum contaminant levels 
(MCLs).
    OU2 is subdivided into areas based on the distribution of unique 
smelter and mill wastes. Included within OU2 are the silver refinery 
area and the Butterfield Lumber property. In addition, numerous piles 
of smelter slag and other smelter wastes were distributed broadly 
across this area.
    The EPA proposed the Site to the NPL based on studies conducted 
between 1982 and 1985 that found groundwater, soil and sediments 
contaminated with heavy metals. Potential human health threats included 
drinking contaminated groundwater or ingesting, inhaling, or handling 
contaminated soils, wastes or sediments. The EPA fenced portions of the 
Site in December 1990 to restrict access to the contaminated wastes.
    The EPA conducted eight removal actions at this Site. The first 
removal action after the NPL listing occurred on June 20, 1991, with 
the disposal of explosives and lab chemicals at a former on-Site lab. 
Additional removal actions conducted between 1995 and 2001 included: 
Construction of additional fencing, contaminated soil removal, plugging 
contaminated water supply wells, removal of approximately 90 
deteriorated drums, and preservation work for the small Midvale Pioneer 
Cemetery located near the southeastern corner of the Site.

Remedial Investigation and Feasibility Study (RI/FS)

    Remedial Investigation for OU1: The suspected waste areas within 
OU1 were a small landfill and an abandoned waste water treatment plant 
with its associated lagoons. Analysis of sample data determined that 
neither area contributed to the contaminants of concern detected in 
Site soils. Soil contamination was caused by smelter waste from OU2 
transported by environmental factors as well as deliberate use of waste 
as fill. The Baseline Risk Assessment determined arsenic, cadmium, and 
lead as the contaminants of concern in soils at OU1. The OU1 
Feasibility Studies (FS) were completed in 1995 for the trailer park 
located on the northern end of the Site, and in 1998 for the remaining 
portions of OU1.
    Remedial Investigation for OU2: The Site investigations for OU2 
focused on mixed smelter waste, slag, and groundwater. These were 
evaluated during Site investigations conducted for the Engineering 
Evaluation/Cost Analysis (EE/CA) prepared in 1993, the Supplemental 
Remedial Investigation in 1997 and 1998, and additional 
characterizations performed in 2001 and 2002. Surface and subsurface 
soil samples were analyzed in five mixed smelter waste areas, calcine 
waste, silver refinery waste, and contaminated soils.
    Metals analysis of samples in the former baghouse dust pond area 
contained high levels of arsenic trioxide which was determined to be 
principal-threat waste (later classified as Category I waste). Four 
areas of slag-covered surfaces were also sampled: Air-cooled slag, 
water-quenched slag, copper slag, and iron slag for the EE/CA. Analysis 
of the slag in these areas found that this slag is not leachable in 
concentrations that impact groundwater. The smelter waste and soil 
maximum contaminant concentrations were 20,400 mg/kg for arsenic and 
26,300 mg/kg for lead. The sediment maximum contaminant concentrations 
were 96 mg/kg for arsenic and 721 mg/kg for lead.
    Groundwater evaluations were conducted in the EE/CA. Additional 
groundwater studies and RI work was conducted between 1997 and 2002. 
The RI activities found significant arsenic in groundwater under the 
old smelter works area. The area around the former arsenic plant and 
baghouse exhibited the highest levels of arsenic contamination in 
ground water at an elevated concentration of 1,300,000 parts per 
billion (ppb). The Upper Sand and Gravel (US&G) Aquifer, which 
underlies the entire Site from about 15 to 150 feet below ground 
surface (bgs), was found to contain a plume that is contaminated with 
arsenic up to 4,000 ppb. The Deep Principal Aquifer, which is below the 
US&G Aquifer which is used for drinking water is clean. During the Site 
investigations in 2001 and 2002, a tetrachloroethylene (PCE) plume 
crossing the Site was identified and referred to UDEQ for further 
investigation. Since the source of the PCE plume is not on the Site, 
CERCLA action is not appropriate. In 2001, surface and subsurface soil 
samples were collected from former river meander locations, upland 
areas of the corridor, and both banks of the Jordan River. Elevated 
levels of metals were detected in surface and subsurface soil samples, 
but not the surface water. Consequently, portions of the Jordan River 
riparian corridor adjacent to the former smelter were added to the Site 
in the 2006 Explanation of Significant Differences for OU2.
    The April 2002 OU2 FS is for the groundwater and the May 2002 OU2 
FS is for mixed smelter waste. Many remedial technologies were 
considered, including no action, institutional controls, treatment, and 
disposal.

Summary of Risk Assessment Activities

    Results of the baseline risk assessment indicate that contaminants 
identified in the RI in Site surface and subsurface soil pose a risk of 
excess cancer and adverse health effects to current and future 
populations at the Site. Risks to future residents, future workers, and 
current and future trespasser scenarios exceed acceptable threshold 
levels. Estimated risk and hazard were greatest for potential future 
residents at the Site. Contaminants in shallow ground water also pose a 
risk to future residents and workers. However, shallow ground water is 
not currently used as a source of drinking water.
    Redevelopment plans for the Site preclude the presence of 
ecological receptors throughout most of the Site. Exceptions consist of 
the Jordan River and the recreational park planned for the riparian 
area on the east bank of the Jordan River. Results of the ecological 
risk assessment indicate that contaminants in sediment and surface 
water pose little risk to aquatic receptors. In addition, Site data 
indicate that the Site is contributing very little to contaminants 
concentrations detected in sediment and surface water. Upstream sources 
are the likely contributors to detected concentrations. However, 
contaminants are present in the riparian area at concentrations that 
could pose a

[[Page 6461]]

potential threat to aquatic receptors if allowed to enter the river; 
therefore, bank stabilization was completed to minimize migration of 
contaminants into the river.
    The recreational park is unlikely to provide significant habitat 
for terrestrial receptors. It is more likely that wildlife will have 
sporadic exposure in the area. It is anticipated that remedial action 
performed to protect child recreational visitors at the park will also 
be protective of terrestrial receptors.

OU1 Selected Remedy

    On April 28, 1995, EPA issued a Record of Decision (ROD) for OU1 
selecting the following remedy: (1) Excavation of a minimum of 18 
inches of soil in 14 residential yards in the Winchester Estates 
development, placement of clean fill and off-site disposal of soils. 
(2) The placement of a 2-foot thick monolayer soil cover over an 
undeveloped portion of the Winchester Estates. (3) Institutional 
controls for the area receiving the soil cover. (4) Institutional 
controls for four other parcels prohibiting future residential land use 
without additional remediation. (5) Ground water monitoring at the 
hydraulically downgradient Site boundary for a minimum of 5 years.
    In May 1998 and also in February 2006, EPA and UDEQ issued 
Explanation of Significant Differences (ESDs) changing the remedy 
called for in the 1995 OU1 ROD. The 1998 ESD required the excavation of 
contaminated soils on one parcel of land, rather than capping, and thus 
eliminated the need for ICs on that parcel. The 2006 ESD changed land 
use restrictions to accommodate multiple land uses, created a 
consistent approach for both operable units, included riparian 
management (both sides of the river) and contained a comprehensive 
groundwater monitoring plan in coordination with the OU2 remedy. The 
2006 ESD identified the lack of remedial action objectives for 
groundwater in the OU1 ROD and adopted the remedial action objectives 
selected for groundwater in the OU2 ROD. A final ESD was issued in 
October, 2013, clarifying the groundwater Remedial Action Objectives 
(RAOs) for OU1 and OU2.
    The amended RAOs for OU1 are as follows: (1) Soil RAO--Prevent 
unacceptable exposure risks to current and future human populations 
presented by contact, ingestion, or inhalation of smelter materials, 
associated contaminated materials, or contaminants of concern (COCs) 
derived from the smelter wastes. (2) Ground Water RAOs--Prevent 
unacceptable exposure risk to current and future human populations 
presented by direct contact, inhalation, or ingestion of contaminated 
ground water. Provide that future migration of COCs into previously 
uncontaminated portions of the US&G Aquifer and into the Deep Principal 
Aquifer is protective of these aquifers as sources of drinking water. 
Provide that future discharge of contaminated ground water from the 
Site to the Jordan River is protective of the aquatic environment and 
designated use.

OU2 Selected Remedy

    On October 29, 2002, EPA signed the Record of Decision for OU2. The 
OU2 ROD defined four categories of smelter wastes found throughout OU2. 
Principal threat wastes such as crude arsenic trioxide were designated 
as Category I waste. Category II wastes included non-slag soils and 
smelter waste failing Toxicity Characteristic Leaching Procedure (TCLP) 
and containing COCs above commercial land use-based remediation goals. 
Category III wastes included non-slag soils and smelter wastes passing 
TCLP and containing COCs below residential land use-based remediation 
goals. EPA classified slag as Category IV waste. The major components 
of the selected remedy include: (1) Ground Water: The Deep Principal 
Aquifer which is a primary source of drinking water in the Salt Lake 
Valley, is not impacted by the Site, although the shallower US&G is 
impacted by the Site. The limited action remedy for ground water does 
not actively attempt to restore the US&G, but provides compliance 
points for monitoring and assessing as well as institutional controls. 
The limited action approach relies on ground water and surface water 
monitoring to assess whether ground water and surface water criteria 
are being met for selected COCs. These selected COCs were established 
as a result of using alternate concentration limit (ACL) calculations 
and site-specific analyses to be protective of surface water quality 
criteria for the Jordan River. An IC to restrict well installation was 
also selected as a part of the remedy. The ACLs for the four 
groundwater COCs were set at the following: Arsenic 7,000 [micro]g/L; 
Cadmium 1,560 [micro]g/L; Selenium 900 [micro]g/L; and Antimony 380 
[micro]g/L. (2) Mixed Smelter Waste: The selected remedy for mixed 
smelter waste required the excavation and off-Site disposal of Category 
I Material, if found, and the installation of appropriate covers over 
the remainder of the Category II and III Materials. (3) Slag: The 
selected remedy for the slag (Category IV Material) required re-grading 
of the slag piles and the installation of appropriate covers. (4) Land 
use controls (ICs) were also selected for OU2 to restrict future 
excavations and guide future use of the property.
    The 2006 ESD added the riparian area along the Jordan River 
corridor to the Site to prevent river migration erosion which could 
impact the remedy. In addition, the ESD eliminated the need for ICs on 
portions of OU1 which were clean and called for a site wide groundwater 
monitoring plan. The 2013 ESD clarified the RAOs for groundwater for 
both OU1 and OU2. This clarification removed the groundwater 
restoration RAO for both OUs.
    The amended RAOs for OU2 are as follows: (1) Ground Water RAOs--
Prevent unacceptable exposure risk to current and future human 
populations presented by direct contact, inhalation, or ingestion of 
contaminated ground water. Provide that future migration of COCs into 
previously uncontaminated portions of the US&G Aquifer and into the 
Deep Principal Aquifer is protective of these aquifers as sources of 
drinking water. Provide that future discharge of contaminated ground 
water from the Site to the Jordan River is protective of the aquatic 
environment and designated use. (2) Mixed Smelter Waste RAOs--Prevent 
unacceptable exposure risks to current and future human populations 
presented by contact, ingestion, or inhalation of smelter materials, 
associated contaminated materials, or COCs derived from the smelter 
areas. Prevent unacceptable exposure risks to current and future 
ecological receptors presented by contact, ingestion, inhalation, or 
uptake from smelter materials, associated contaminated materials, or 
COCs derived from the smelter areas. Provide that the future migration 
of contaminants from the smelter materials is within limits considered 
protective of ground water. Prevent smelter materials from entering the 
Jordan River via surface water flow. (3) Slag RAOs Prevent unacceptable 
exposure risks to current and future human populations presented by 
contact, ingestion, or inhalation of slag or associated contaminated 
materials. Prevent unacceptable exposure risks to current and future 
ecological receptors presented by uptake from slag, associated 
contaminated materials within slag, or COCs derived from the slag 
areas. Provide that the future migration of contaminants from the slag 
or contaminated materials within slag is within limits considered 
protective of ground water. Prevent slag or

[[Page 6462]]

contaminated materials within slag from entering the Jordan River via 
surface water flow.

Response Actions

    UDEQ was the lead agency for the OU1 remediation as defined in a 
cooperative agreement between EPA and UDEQ. Remediation work was 
conducted in two phases, with work on the residential portion of 
Winchester Estates portion beginning in September 1995 and ending in 
April 1996. Remediation of the undeveloped southeast portion of 
Winchester Estates was completed by November 1998. The final inspection 
of the OU1 remedial action occurred in January 1999 and the RA report 
for OU1 signed in March 1999. EPA and UDEQ installed the groundwater 
monitoring system and performed the riparian remediation selected in 
the 2006 ESD during the implementation of the OU2 remedy.
    A consent decree governed work conducted by the main property 
owner, Littleson, Inc. In the consent decree signed with EPA, Midvale 
City, and the Union Pacific Railroad, the property owner, Littleson, 
Inc., agreed to perform the remedial design/remedial action (RD/RA) for 
the smelter wastes, slags and impacted soils components of the OU2 ROD 
remedy. In the consent decree, Midvale City agreed to enact and enforce 
ICs in the form of an ordinance. This consent decree was entered on 
November 16, 2004.
    UDEQ was the lead for the ground water portion of the OU2 ROD 
remedy as well as the 2006 ESD for OU1. This work was performed under a 
cooperative agreement with EPA. EPA was the primary lead for the 
riparian portion of the OU2 ROD remedy.

Smelter Wastes, Slags, and Impacted Soils

    Littleson, Inc., completed all remedial activities as planned, and 
no additional areas of contamination were identified. EPA, UDEQ and 
Midvale City conducted a final inspection of the work upon completion 
of the physical construction on June 26, 2006. A one-year warranty 
period began on July 6, 2006, to ensure that the remedy continued to 
operate as designed. On May 15, 2007, EPA, UDEQ and Midvale City 
representatives conducted a second final inspection to verify that the 
remedy remained effective. This remedy was declared operational and 
functional on August 13, 2007 when EPA approved the Remedial Action 
Report. On the same day, EPA certified the completion of the 
construction work required under the consent decree.

Riparian Zone OU1 and OU2

    EPA and UDEQ conducted the RD/RA work along 6,800 feet of the 
Jordan River riparian corridor adjacent to the western boundary of the 
Site. The objective for this work included the reduction and 
elimination of river bank erosion that could release smelter waste from 
the Site into the river. This work was conducted in four phases, with 
the final phase being completed in August 2011. Salt Lake County 
conducted the Phase 3 portion of this work under EPA and UDEQ 
oversight. Phase 3 involved completing the riparian work from 
Winchester Estates south along the eastern bank of the Jordan River and 
was funded through a grant from EPA using special account funding.
    EPA, UDEQ and Salt Lake County completed all remedial activities as 
planned. EPA and UDEQ conducted a pre-final inspection on August 10, 
2011, which included a description and schedule for correcting minor 
construction contract items by the contractor. The remaining ``punch'' 
list item was replacement of some damaged vegetation. EPA and the State 
determined that all Riparian Zone work was constructed and/or completed 
according to the ROD and design specifications in 2013.

Groundwater OU1 and OU2

    UDEQ completed the installation of the groundwater monitoring 
system in December 2008. Construction of the system was completed under 
a cooperative agreement established between the EPA and UDEQ. Under 
this cooperative agreement, the UDEQ implemented the groundwater 
monitoring system design developed by the EPA and conducts quarterly 
monitoring. In September 2009, EPA approved the groundwater Remedial 
Action Report in which EPA determined that construction of the 
monitoring system was complete in accordance with the OU2 ROD and 
design specifications.
    UDEQ conducts semi-annual groundwater and surface water monitoring 
at the Site using a plan developed during the remedial design. The 
monitoring system at the Site currently consists of co-located wells at 
15 locations (a total of 30 wells) and two surface water sampling 
locations. Each well pair consists of one shallow monitoring well, 
screened in the upper interval of the US&G Aquifer, and one 
intermediate monitoring well, screened at a lower interval within the 
US&G Aquifer. The monitoring system is divided into four groups and 
consists of up-gradient, down-gradient, plume core and ACL monitoring 
wells. The process for developing ACLs is discussed in the OU2 ROD with 
supporting documentation provided in the Administrative Record.
    Although the selected remedy did not attempt to actively restore 
the US&G Aquifer, it provided for the monitoring of groundwater and 
surface water to assess whether applicable groundwater and surface 
water quality criteria are being met for the selected COCs. It also 
provided for the creation of ICs to prevent exposure to the 
contaminated US&G Aquifer.
    Point of assessment locations for monitoring the US&G Aquifer were 
selected based on the location and movement of arsenic contamination on 
the Site. Arsenic was selected as the indicator chemical since it is 
the most mobile and widespread of the COCs in this aquifer. Monitoring 
wells for points of assessment were installed in the shallow and deep 
portions of the US&G Aquifer in accordance with plans and 
specifications developed during the remedial design. The specific 
monitoring objectives are as follows: (1) Conduct groundwater and 
surface water monitoring to assess if applicable groundwater and 
surface water quality criteria are being met for COCs (antimony, 
arsenic, cadmium and selenium). (2) Assess monitoring data and 
determine if contamination is moving laterally or vertically within the 
boundaries of the Site.
    The UDEQ's Semi-Annual Groundwater and Surface Water Monitoring 
Report--Midvale Slag Superfund Site dated May 24, 2013 states that 
``COC concentrations in the ACL monitoring wells have not exceeded 
their respective ACL values and that COC concentrations in surface 
water have not exceeded established surface water quality criteria 
values for the Jordan River in monitoring results from 2008 to 
present.''

Operation and Maintenance

    Maintaining an appropriate soil cover with adequate drainage is an 
operation and maintenance activity required as an IC. Midvale City is 
responsible for this IC and conducting the following activities: 
Inspection/observation during redevelopment construction; review of 
development construction plans and specification for conformance with 
cover requirements; storm water management and irrigation restrictions; 
and temporary stockpile and covering of soil and slag. UDEQ conducts 
semi-annual groundwater and surface water monitoring at this Site. COC 
concentrations in the ACL monitoring wells have not exceeded their 
respective

[[Page 6463]]

ACL values and COC concentrations in surface water have not exceeded 
established surface water quality criteria values for the Jordan River 
in monitoring results from 2008 to present.
    ICs adopted by the Midvale City support limited commercial and 
residential re-use of this Site. The OU2 ROD required the establishment 
of ICs including land use controls, to prevent exposure to contaminated 
materials and review of proposals to change the type of land use at the 
Site. In addition, ICs for groundwater and surface water were 
established to prevent access to contaminated ground and surface water 
and to limit the infiltration in the plume area. Additionally, 
groundwater beneath the Site is not used for drinking water under the 
State of Utah ICs.
    An Institutional Control Process Plan for OU1 was developed in 2004 
as a mechanism to assure that consistent and effective inspection, 
maintenance and enforcement activities occurred throughout the Site. 
The objective of the ICs are (i) to limit or prohibit exposure of 
people and the environment to subsurface contaminants remaining at the 
Site by ensuring the protection and maintenance of the cap; (ii) to 
prevent or limit certain activities in certain areas of the Site that 
may increase the risk of damage to the cap; and (iii) to manage 
stormwater and irrigation water to prevent unacceptable impact to the 
cap and underlying groundwater.
    In 2007, an ordinance for Bingham Junction, Jordan Bluffs and 
designated rights-of-way was implemented by Midvale City which set 
forth the requirements and procedures for the public ICs for the 
redevelopment and reuse of the Bingham Junction and Jordan Bluffs 
properties. The purpose of the ICs was to prevent unacceptable human 
exposure to contaminants that remain on Site by ensuring the 
protection, maintenance, and improvement of physical barriers that had 
been on the various properties.
    Midvale City is responsible for enforcement of the land use ICs. 
Midvale City utilizes a grant from EPA to hire a Development Site 
Coordinator who is responsible for enforcing the ICs and provides IC 
on-Site training for the developer's Special Inspectors when needed. 
The Special Inspectors, as well as the Development Site Coordinator, 
know which areas of the Site have buried contamination and the exact 
location of the protective cap or inert slag demarcation layer located 
above the contamination. Midvale City issued permits identify planned 
development above the demarcation layer. The Development Site 
Coordinator conducts inspections several times a day during 
construction as well as visits temporary soil stockpiling, road 
construction, storm drain, and landscaping phases of the work to ensure 
that the ICs are being followed and the remedy remains protective. In 
addition, the Development Site Coordinator monitors the riparian 
restoration area and maintains ongoing weekly communication with UDEQ, 
EPA and Salt Lake County.

Five-Year Review

    Three statutory five-year reviews have been conducted at the Site: 
in October 2003, December 2008, and April 2014. The remedy at the Site 
was determined to be protective and no issues were identified in the 
latest five-year review. Pursuant to CERCLA section 121(c) and the NCP, 
EPA will conduct the next five-year review to ensure the continued 
protectiveness of remedial actions where hazardous substances, 
pollutants, or contaminants remain at the Site above levels that allow 
for unlimited use and unrestricted exposure. The next five-year review 
is scheduled for completion by April 2019.

Community Involvement

    Major community involvement activities at the Site initially 
included establishing a local information repository and forming a 
Technical Advisory Group (TAG) and working with the Jordan River 
Stakeholders Group. EPA, with representatives from the UDEQ, conducted 
community interviews with a broad array of interested residents, agency 
representatives, local elected officials and others. These interviews 
were the foundation of the Site Community Involvement Plan and 
information from these interviews was considered in the remedy 
selection process for the Site. Outreach efforts included community 
interviews, fact sheets, letters, flyers, door-to-door visits, public 
meetings, neighborhood meetings, public comment periods and Web site 
updates. The most recent interviews were conducted in the Spring 2013 
for the upcoming five-year review.
    Because the community requested future development be considered in 
the remedy selection, slag piles were graded to better support 
redevelopment and appropriate soil covers were designed as an interim 
measure to facilitate future redevelopment. The Site is located right 
off the I-15 and I-215 freeways, barely 20 minutes from most Salt Lake 
County locations. On August 29, 2006, Midvale Mayor Joanne Seghini 
said, ``The land constitutes 20 percent of Midvale and is one of the 
last pieces of undeveloped property in the City and was a discouraging 
blight.'' Redevelopment began once the institutional controls were 
established. A Ready for Reuse Determination was issued by EPA in 2008.
    Today, approximately 70 percent of the Site has been fully 
developed for mixed-use that incorporates major retail and office 
space, along with needed housing for Midvale City. The Utah Transit 
Authority mass transit train system opened a station at the Site which 
serves the ``green sustainable community.'' The successful 
revitalization of the Midvale community is sustainable, provides mixed 
use, and elevates the quality of life with revitalization for years to 
come. Improvement of the riparian corridor and bike trail along the 
Jordan River has also helped this area thrive. These successful efforts 
have resulted in the influx of new residents now inhabiting the Site.

Determination That the Site Meets the Criteria for Deletion

    The implemented Site-wide remedy achieves the RAOs specified in the 
1995 ROD, 2002 ROD, and 1998, 2006 and 2013 ESDs for all pathways of 
exposure. No further Superfund responses are needed to protect human 
health and the environment at the Site.
    The NCP (40 CFR 300.425(e)) states that a Site may be deleted from 
the NPL when no further response action is appropriate. EPA, in 
consultation with UDEQ, has determined that all required response 
actions have been implemented and no further response action by 
responsible parties is appropriate.

V. Deletion Action

    The EPA, with concurrence of the State of Utah through the Utah 
Department of Environmental Quality (UDEQ), has determined that all 
appropriate response actions under CERCLA, other than operation, 
maintenance, monitoring and five-year reviews have been completed. 
Therefore, EPA is deleting the Site from the NPL.
    Because EPA considers this action to be noncontroversial and 
routine, EPA is taking it without prior publication. This action will 
be effective April 6, 2015 unless EPA receives adverse comments by 
March 9, 2015. If adverse comments are received within the 30-day 
public comment period, EPA will publish a timely withdrawal of this 
direct final notice of deletion before the effective date of the 
deletion, and it will not take effect. EPA will prepare a response to 
comments and continue with the deletion process on the basis of the 
notice of intent to delete and the

[[Page 6464]]

comments already received. There will be no additional opportunity to 
comment.

List of Subjects in 40 CFR Part 300

    Environmental protection, Air pollution control, Chemicals, 
Hazardous substances, Hazardous waste, Intergovernmental relations, 
Penalties, Reporting and recordkeeping requirements, Superfund, Water 
pollution control, Water supply.

    Dated: January 23, 2015.
Shaun L. McGrath,
Regional Administrator, Region 8.
    For the reasons set out in this document, 40 CFR part 300 is 
amended as follows:

PART 300--NATIONAL OIL AND HAZARDOUS SUBSTANCES POLLUTION 
CONTINGENCY PLAN

0
1. The authority citation for part 300 continues to read as follows:

    Authority:  33 U.S.C. 1321(c)(2); 42 U.S.C. 9601-9657; E.O. 
13626, 77 FR 56749, 3 CFR, 2013 Comp., p.306; E.O. 12777, 56 FR 
54757, 3 CFR, 1991 Comp., p.351; E.O. 12580, 52 FR 2923, 3 CFR, 1987 
Comp., p.193.

Appendix B to Part 300--[Amended]

0
2. Table 1 of Appendix B to part 300 is amended by removing the entry 
for ``UT'', ``Midvale Slag'', ``Midvale''.

[FR Doc. 2015-02326 Filed 2-4-15; 8:45 am]
BILLING CODE 6560-50-P