proposed plan oklahoma refining company superfund … · oklahoma deq 707 n. robinson, 6. th. floor...

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Oklahoma Department of Environmental Quality announces Proposed Plan

This Proposed Plan, part of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) process (Figure 1), identifies the preferred alternatives for remediating soil, sediment, and Light Non-Aqueous Phase Liquid the at the Oklahoma Refining Company Superfund Site (Site), Cyril, Oklahoma; and provides the rationale for this preference. This proposed plan is for a Record of Decision to remediate soil, sediment, and Light Non-

aqueous Phase Liquid at the Oklahoma Refining Company Superfund Site. In addition, this Plan includes summaries of other cleanup alternatives evaluated for use at this Site. This document is issued by the Oklahoma Department of Environmental Quality (DEQ), the lead agency for Site activities, in consultation with the United States

Environmental Protection Agency, Region VI (USEPA). The remedy will be selected for the Site after reviewing and considering all information submitted during the 30-day public comment period on the Proposed Plan (see right). Based on new information or public comments, DEQ, in conjunction with the USEPA, may modify the preferred alternatives or

select other response actions. Therefore, the public is encouraged to review and comment on the alternatives presented in this Proposed Plan.

The DEQ is issuing this Proposed Plan as part of its public participation responsibilities under Section 300.430(f)(2) of the National Oil and Hazardous

Substances Pollution Contingency Plan (NCP) and the CERCLA of 1980 §117(a). This Proposed Plan summarizes information that can be found in greater detail in the Remedial Investigation (RI), and the Feasibility Study (FS) Reports and other documents

Dates to Remember:

Public Comment Period:

January 15, 2013-February 22, 2013

The DEQ and EPA will accept written comments on the Proposed Plan during the public comment period.

Public Meeting: February 21, 2013

The DEQ will hold a public meeting to explain the Proposed Plan and all of the alternatives presented in the Feasibility Study. Oral and written comments will also be accepted at

the meeting. The meeting will be held at the Cyril City Hall, 202 W. Main, Cyril, Oklahoma at 6:00 pm.

The Administrative Record including copies of the RI and FS reports are available for viewing at:

Anadarko Community Library

215 W. Broadway, Anadarko, Oklahoma

Hours: 9 am to 6 pm Monday thru Thursday

9 am to 5 pm Friday, 9 am to 12 pm Saturday

Closed on Sunday

Oklahoma DEQ

707 N. Robinson, 6th Floor Central Records

Oklahoma City, Oklahoma

405-702-1188

Hours: 8:00 am to 4:30 pm Monday thru Friday

Copies can be requested from:

USEPA

1445 Ross Avenue

Dallas, TX 75202-2733

214-665-8315

Figure 1 - The CERCLA Process

Proposed Plan

Oklahoma Refining Company Superfund Site

Operable Unit 2

Cyril, Oklahoma

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Proposed Plan Oklahoma Refining Company Superfund Site, Cyril, Oklahoma

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contained in the Administrative Record for this site. The DEQ encourages the public to review these documents to gain a more complete understanding of the Site and investigation activities that have been conducted at the Site.

The following are the preferred remedial alternatives:

Soil and Sediment Alternative 7C: Excavate and dispose of approximately 103,644 cubic yards of soil and sediment.

Light Non-Aqueous Phase Liquid Alternative 6: Install LNAPL Recovery systems in wells with greatest LNAPL thickness and monitor for thickness of LNAPL in wells.

SITE BACKGROUND The ORC Site was an operating oil refinery with operations beginning in 1920. Refinery operations continued until 1984 with intermittent attempts to restart the refinery in limited capacity through 1994.

Petroleum refinery operations began at the Site in 1920 under the Anderson Prichard Company (APCO),

later renamed the Anderson Prichard Oil Corporation. The APCO facility was purchased by Oklahoma Refining Company in 1978, and refining capacity continued to increase to a peak of 15,000 barrels a day in 1983. Refined products included gasoline, diesel, jet fuel, naphtha, heating oil, asphalt, and industrial solvents, such as Stoddard Solvent (Stod-

Sol®). On-site facilities included the refinery processing area, bulk storage areas (tank farm), various wastewater treatment ponds, waste pits, a land treatment unit, an asphalt plant, and an API Separator system for process wastewaters.

In 1986, the Bankruptcy Court allowed Oklahoma Refining Company to abandon the southern portion of the property. The northern portion (refining operational area) remained under the Resource Conservation and Recovery Act until 2002 because of various attempts to resume refining operations at the site. Environmental issues on the abandoned portion of the site fell under CERCLA. The abandoned portion of the site is commonly referred to as “ORC

South” and the former process area (area primarily

northwest of the railroad tracks) is referred to as

“ORC North”. The boundaries for ORC North and ORC South are shown in Figures 4 and 5.

Decades of petroleum refining resulted in widespread organic and inorganic contamination in surface soil, sediments, subsurface soil, and ground water. A CERCLA Remedial Investigation (RI) and baseline risk assessment were completed in September 1991 followed by a Feasibility Study (FS) in December 1991. Limited investigation was completed on ORC North since the refinery was still in operation on this portion of the property.

From September 1990 until August 1991, the USEPA completed a time-sensitive removal action that focused on the removal of hazardous wastes, disposal of drums, netting of API separator units, and skimming of ponds.

A Record of Decision (ROD) was issued by USEPA in 1992. The selected remedy addressed all known contaminated media (surface water, sediment, surface soil, and ground water on ORC) identified in the 1991 Remedial Investigation on ORC North and ORC South.

In accordance with the National Contingency Plan (NCP), publishing of an Explanation of Significant Difference (ESD) is required when the remedial action to be implemented differs significantly from the remedy selected in the ROD with respect to scope, performance, or cost. Ground water treatment was postponed in ESD documents of 1996 and 2003 until a second phase of remedial construction following implementation of the source remedy, after which the ground water treatment would be re-evaluated. From July 1997 until January 2002, the Philip Services Corporation under contract with Oklahoma State Department of Health (OSDH) performed a remedial action that focused on treatment of soils and removal of hazardous waste from ORC South.

In late 2003, after the site was deferred (August 2002) from RCRA to CERCLA, EPA Region 6 conducted removal actions to remove hazardous substances from ORC North. Previous removal and remedial activities have not completely addressed the identified contamination in ground water, ORC North soils and sediments, or the LNAPL plume beneath the Site.

Since the time that the 1991 RI/FS was completed, numerous additional environmental investigations and monitoring events have been completed at the site to provide additional site

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characterization. In 2009, DEQ completed the Phase 1 Data Summary Report.

A Supplemental Feasibility Study (SFS) was completed in September 2012 to evaluate cleanup alternatives for the remaining contaminated media at the Site, including the areas referred to as ORC North and ORC South. The SFS did not evaluate the previous remedy. The SFS evaluated contaminated media which was not addressed in the previous remedy. This proposed plan will present the results of the Supplemental Feasibility Study.

SITE CHARACTERISTICS The ORC site is located in Cyril, Caddo County, Oklahoma approximately 75 miles southwest of Oklahoma City. The site is bordered by the City of Cyril to the west and southwest, US Highway 277 to the north, and Gladys Creek and tributary to the east and south. The Site covers approximately 181.84 acres. The Site location is shown in Figure 2.

ORC South formerly consisted of uncultivated grasslands and approximately 40 pits, a land treatment unit, wastewater ponds, sludge lagoons, etc. of varying shapes and sizes. On-site pond sediment, soil, and on-site pond surface water on ORC South have been remediated, and two capped, fenced, and revegetated landfills have been constructed on this portion of the site.

ORC North includes the former North Process Area (NPA), tank farm, and area north of US Highway 277. Removal of the refinery structures and partial remediation of soils were completed as part of a removal action initiated in 2003 on ORC North.

The ORC site is located within a mostly flat, gently sloping local topographic terrain. Topography of the Site generally slopes towards Gladys Creek or its tributary, which together border the northern, eastern, and southern site boundaries. This creek system is deeply incised with steep embankments where it borders the eastern and southern ends of the Site. Creek banks north of US Highway 277 are more sloping. The northwest corner of the Site has the highest on-site elevation at approximately 1,380 feet above mean sea level (msl). The lowest elevation is at the bottom of Gladys Creek in the southeast corner, which is approximately 1,290 feet above msl.

Gladys Creek is the nearest water body to the Site. Gladys Creek has been designated as a habitat-

limited fishery and for usage as a secondary body contact recreational area by the Oklahoma Water Resources Board Water Quality Standards (OAC 785:45). The unnamed tributary of Gladys Creek that also borders the Site supports continuous flow throughout the year and is assumed to also be capable of supporting the same beneficial use designation. Gladys Creek flows southerly into Chetonia Creek (approximately one mile downstream), which empties into the Little Washita River (approximately 1.75 miles south of

the ORC site).

ORC site soils are primarily red silty clay loam varieties of deep upland soils. Soils are typically well drained with low to very low permeabilities, although soils in the northeast portion of the site have been observed to allow surface ponding. Sands, silts, and gravels in alluvium and terrace sediments also occur in and around old stream channels.

General lithologies present at the ORC Site include Quaternary sedimentary deposits, gypsum, clay, and sandstone. The unconsolidated Quaternary deposits are generally composed of clay, silt, and sand overlying bedrock. These deposits are found in varying thicknesses often as discontinuous channel-fill type deposits. These shallow Quaternary deposits are not used as a local water source.

The uppermost bedrock at the site consists of the Permian Weatherford Member of the Cloud Chief Formation. The Weatherford Member is primarily gypsum although it does contain anhydrite and is dolomitic in places. It underlies shallow quarternary age clay deposits in the Northwest quarter of the site but outcrops or is absent in other areas of the ORC Site. The thickness and elevation of the top of the Weatherford varies due to the fact that it is an erosional surface. The greatest measured thickness of the Weatherford at the ORC Site has been 31.5 feet.

According to the 1992 ROD, the Weatherford

Member acts as an aquitard to vertical migration in the northwest portion of the site. During investigations performed after the 1992 ROD loss of circulation during drilling through the Weatherford indicates that open solution cavities

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or fractures exist in the gypsum. LNAPL migrates from the solution cavities and fractures in the gypsum to the upper Rush Springs Sandstone Aquifer. The LNAPL migrates laterally with the ground water flow towards Gladys Creek. The Weatherford Member is not used as a local water source.

The Rush Springs Sandstone (RSS) Formation is the uppermost drinking water aquifer beneath the Site. The RSS is an unconfined water table aquifer classified as a Class IIA Aquifer in the Cyril area (according to the EPA Ground Water Protection Strategy), and conformably underlies the Weatherford Member. Ground water flow direction has remained relatively constant from 1991 to 2011 with a low gradient mound in the refinery area where ground water flows outward toward the tributaries and Gladys Creek. The RSS has been contaminated with LNAPL from leaking tanks, spills, and other waste sources at the ORC Site. Although no one is currently using the portion of the RSS aquifer that is impacted by ORC site contamination as a drinking water source, ground water from the RSS does seep into Gladys Creek at visible seepage discharge points and through the creek sediments. Recharge of the RSS aquifer primarily occurs in the topographically high areas located north and west of the Site (upgradient), and discharge occurs where the RSS outcrops and Gladys Creek and its tributaries intercept the RSS aquifer water table (mostly downgradient of the site). The RSS Formation is approximately 250 feet thick in the Cyril area and consists of an evenly-bedded to highly cross-bedded, reddish-brown, very fine-grained, silty sandstone. The RSS aquifer is the affected aquifer of concern addressed in the 1992 ROD. Contaminant sources and potential routes of migration are shown in Figure 3.

The following sedimentary formations underlie the RSS in descending order: the Marlow Formation, the Dog Creek Shale Formation, the Blaine Formation, and the Flowerpot Shale Formation. The Marlow Formation is mostly a red, sandy shale to fine-grained sandstone of approximate 100-foot thickness in the Cyril area. The other mentioned formations have a combined thickness of approximately 500 feet and are primarily red shale with minor interbedding of gypsum, dolomite, siltstone, and sandstone. According to the 1992 Record of Decision, the Marlow, Dog Creek, Shale, Blaine, and Flowerpot Shale Formations are not considered as aquifers and act as aquitards to ground water flow in the Cyril

area. These formations are not impacted by the ORC site contamination.

A RI/FS was conducted between October 1989 and December 1991. The RI identified the types, quantities, and locations of contaminants and the

FS developed options to address the contamination. The major findings of the RI are listed below.

Contamination was detected in surface soil, subsurface soil, sediments and surface water from waste sources and drainage-ways, and ground water.

Surface soils were found to have elevated

levels of inorganic (metals), especially in the refinery process area.

Subsurface soils were found to have

elevated inorganic concentrations (primarily underlying the identified waste sources) and organic contaminants.

Sampling of Gladys Creek surface water,

sediment, and biological communities (fish and macro-invertebrates) indicated that the

What is a “Principle Threat Waste?”

The NCP establishes an expectation that EPA will use treatment to address the principal threats posed by a site wherever practicable (NCP Section 300.430(a)(1)(iii)(A)). The “principal threat” concept is applied to the characterization of “source materials” at a Superfund site. Source material is any material that includes or contains hazardous substances, pollutants or contaminants that act as a reservoir for migration of contamination to ground water, surface water, air, or acts as a source for direct exposure. Contaminated ground water is not generally considered to be a source material; however, Non-Aqueous Phase Liquids (NAPLs) in ground water may be viewed as source material. Principal threat wastes are those source materials considered to be highly toxic, or highly mobile that generally cannot be reliably contained, or would present a significant risk to human health or the environment should exposure occur. The decision to treat these wastes is made on a site specific basis through a detailed analysis of the alternatives using the nine remedy selection criteria. This analysis provides a basis for making a statutory finding that the remedy employs treatment as a principal element.

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creek was not significantly impacted by ORC site contaminants, other than in the areas of ground water seepage from the former acid and caustic pits. These seeps are referred to as the acid and caustic seeps.

Metals, VOCs, SVOCs (including PAHs), and

LNAPL were the primary ground water contaminants. LNAPL was present in two major plumes, one within a perched water zone above the gypsum layer and a lower plume

within the RSS. Measured apparent LNAPL thickness ranged 0.5 feet to 16.9 feet in 20 wells.

Since the time that the 1991 RI/FS was completed, a succession of removal and remedial actions have been completed at the Site. The SFS discusses the contaminated media remaining on-site based on the cumulative data compiled from investigations at the site after completion of these removal and remedial actions. A chronology of actions and investigations conducted at the site since the 1991 RI/FS is shown in Table 1.

Remaining areas of contaminated media include ORC North surface soil, ORC North subsurface soils, sediments, surface water, and site wide ground water. Sediments include Gladys Creek sediment and on-site pond sediment, and sediment from the railway drainage ditch.

The “on-site ponds” are areas where contaminated sediment and subsurface soil were excavated during the Remedial Action. These areas were not backfilled and instead left as a stormwater retention area. Contaminated sediments remaining in these stormwater retention areas could provide a potential pathway for contaminant migration to ground water.

Areas of surficial asphaltic waste have been visually identified on ORC North. These areas will be sampled during the Remedial Design (RD) Phase. If the RD sample results indicate constituents of concern above soil preliminary remediation goals, these areas will be included under the Soil and Sediment Alternative 7C. The following results of

investigations performed since the 1991 RFS are discussed in the SFS:

Surface soil samples from surface soils on North ORC have shown concentrations of metals including arsenic (<5mg/kg-35.7mg/kg), lead(34mg/kg-3500mg/kg), and

mercury(0.11mg/kg-138mg/kg) which exceed the

preliminary remediation goals (PRGs) for the Site. Surface soil samples from surface soils on North ORC have also shown concentrations of polyaromatic hydrocarbons including Benzo(a)pyrene(390mg/kg-5820mg/kg), Benzo(a)anthracene(non-detect-5720mg/kg), Benzo(b)fluoranthene(non-detect-2990mg/kg) which exceeded the PRGs for the Site.

Subsurface soil samples from subsurface soils on

ORC North have shown concentrations of

Benzene(296mg/kg-2200mg/kg) and metals including Arsenic(<5mg/kg-29mg/kg) and Lead(34mg/kg-3500mg/kg) which exceed the PRGs for the site. Subsurface soil samples from subsurface soils on ORC North have also shown concentrations of and PAHs including 2-Methylphenol(147mg/kg-159mg/kg), Phenol(129mg/kg-147mg/kg), and Benzo(a)pyrene(0.38mg/kg-0.59mg/kg).

Sediment samples have shown

concentrations of Benzene(430mg/kg-2500mg/kg), Arsenic(27.1mg/kg-63.1mg/kg), and Lead(non-detect-865mg/kg) which exceed the PRGs for the site. Sediment samples have also shown concentrations of PAHs including Benzo(a) pyrene(non-detect-880mg/kg) and Benzo(b)fluoranthene(non-detect-760mg/kg) which exceed the PRGs for the site.

During the 2008 Phase 1 Sampling event conducted by DEQ, surface water samples were collected from the acid and caustic seeps into Gladys Creek and surface water in Gladys Creek. Surface water samples

collected from the seeps detected concentrations of metals including benzene, ethylbenzene, m,p-xylene, o-xylene, toluene, 2,4-dimethylphenol, 2-methylnaphthalene, 2-methylphenol, 4-methylphenol, naphthalene, phenol, arsenic, barium, beryllium, cadmium, chromium,

lead, nickel, zinc, and copper. Contaminants that exceeded the EPA or Oklahoma Water Quality Standards included arsenic, lead, and cadmium. Surface water samples collected from Gladys Creek detected concentrations of benzene, m,p-xylene, 2,4-dimethylphenol, 2-methylnaphthalene, 2-

methylphenol, , 4-methylphenol, arsenic,

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What is Risk and How is it Calculated?

A CERCLA baseline human health risk assessment estimates the "baseline risk." This is an estimate of the likelihood of health problems occurring if no cleanup action were taken at a site. To

estimate the baseline risk at a CERCLA site, EPA identifies a four-step process:

Step 1: Identify Chemicals of Concern

Step 2: Estimate Exposure

Step 3: Assess Potential Health Effects

Step 4: Characterize Site Risk

In Step 1, the risk assessor compiles all the chemical data for a site to identify what chemicals were detected in each medium (i.e.

soil and groundwater). Chemicals that are detected frequently at high concentrations, or are considered highly toxic, are considered “chemicals of concern” and are evaluated in the risk assessment

In Step 2, the risk assessor considers the different ways that people might be exposed to the contaminants identified in Step 1,

the concentrations that people might be exposed to, and the potential frequency and duration of exposure. Using this information, the risk assessor calculates a "reasonable maximum exposure" (RME) scenario, which portrays the highest level of

human exposure that could reasonably be expected to occur.

In Step 3, the risk assessor compiles toxicity information on each chemical, including numeric values for assessing cancer and noncancer adverse health affects. The EPA identifies two types of

risk: cancer risk and noncancer risk. The likelihood of any kind of cancer resulting from a CERCLA site is generally expressed as an upper bound probability; for example, a "1 in 10,000 chance.” In other words, for every 10,000 people that could be exposed, one

extra cancer may occur as a result of exposure to site contaminants. An extra cancer case means that one more person could get cancer than would normally be expected to from all other causes. For noncancer health effects, the risk assessor calculates a "hazard index." The key concept here is that a

"threshold level" (measured usually as a hazard index of less than 1) exists below which noncancer health effects are no longer predicted.

In Step 4, the risk assessor uses the exposure information from

Step 2 and toxicity information form Step 3 to calculate potential cancer and noncancer health risks. The results are compared to EPA acceptable levels of risk to determine whether site conditions could potentially cause health problems for populations at or near

the CERCLA site.

barium, beryllium, chromium, copper, nickel, and zinc. None of the concentrations in samples collected from the creek exceed the Oklahoma or EPA Water Surface Water Quality Standards. Therefore, the creek is being impacted at the seeps, but not in the surface water.

Ground water samples have shown

concentrations of Benzene(1.4ug/L-2810ug/L)

and metals including Arsenic(7.5ug/L-420ug/L), Beryllium(7.5ug/L-332ug/L), Cadmium(9.2ug/L-43.3ug/L) Chromium(17.7ug/L-506ug/L), Lead(2.1ug/L-82.7ug/L), and Nickel(91.5ug/L-178ug/L) exceeding site PRGs. Ground water samples have also shown concentrations of VOCs ans SVOCs including 1,2-Dichloroethane(3.7ug/L-220ug/L), 2,4-Dimethylphenol(10ug/L-5760ug/L), 2-Methylnaphthalene(2.8ug/L-330ug/L), 2-Methylphenol(29ug/L-8940ug/L), 3/4-Methylphenol(37.9ug/L-12400ug/L), Naphthalene(2.4ug/L-364ug/L), and Toluene(1.3ug/L-1600ug/L) exceeding site PRGs.

Samples have shown that there is a light non-

aqueous liquid plume which exists in varying thicknesses across the western side of ORC North. This LNAPL plume is considered a

principal threat waste because it continues to be a source for contaminant migration to ground water. It is estimated that up to 80 acres of the site may have LNAPL on top of the shallow ground water table. The ground water contamination consists of a plume of light non- aqueous phase liquid (LNAPL) and a much larger

dissolved phase plume that ultimately leaves the site via ground water discharge to Gladys Creek.

Relative thickness of the plume, extent of the plume, and mobility of the plume has been monitored historically. Results have shown that the LNAPL plume has been relatively stable for the past 15 years. Monitoring events conducted in 2006 and 2007 have shown LNAPL thickness exceeding PRGs in one off-site well. Monitoring well SBB-2, which is an off-site well located North of Highway 277, had a measurable LNAPL thickness during the October 2006 LNAPL Well Survey. After the 2007 LNAPL monitoring event, three new wells were drilled between residential houses and SBB-2 to delineate

the LNAPL plume. These new wells were gauged to measure LNAPL thickness immediately after

installation. There was no LNAPL detected in any of the new wells.

Areas of surficial asphaltic waste have been visually identified on ORC North which comprise a total area of approximately 3.82 acres. Similar asphaltic waste was analyzed during the

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1991 RI. Metals detected in this waste material included arsenic, barium, cadmium, chromium, copper, lead, nickel, mercury, zinc, and lead. Organic contaminants detected in the waste included 2-methylnaphthalene, phenanthrene, pyrene, and xylene.

These areas of surficial asphaltic waste will be sampled during the Remedial Design phase. If the RD sample results indicate constituents of concern above soil preliminary remediation goals, these areas will be included under the Soil and Sediment Alternative 7C.

SCOPE AND ROLE OF RESPONSE ACTION

A Record of Decision (ROD) was issued by the EPA in June 1992. The remedial action completed as a result of the 1992 ROD is referred to as Oklahoma Refining Company Operable Unit 1. Operable Unit 1 focused on the treatment of soils and removal of hazardous wastes from ORC South and limited areas of ORC North. EPA signed an Explanation of Significant Difference (ESD) to the ROD for the site in March 1996 that included postponement of the ground water remedy until after completion of the source remedy. The DEQ performed the Remedial Action (RA) construction on the south side of the site and in limited areas, mostly waste pits and impoundments, on the north side of the site from 1997 to 2002. The action which will be described in the new ROD will be referred to as the Oklahoma Refining Company Remedial Action Operable Unit 2. Operable Unit 2 is an incremental step toward comprehensively addressing the problems at the Site. The Remedial Action Objectives (RAOs) for Operable Unit 2 for the Site are designed to prevent current and future exposure to contaminated media at the Site. This portion of the remedial response includes excavation and disposal of soil and sediment in the area of the Site referred to as ORC North that was not addressed in the original ROD, as well as the management or mitigation of releases or threatened releases from LNAPL beneath the Site.

The SFS report dated September 10, 2012, contained an evaluation of several different alternatives to address ground water at the site. While it appears that a Technical Impracticability (TI) Waiver is probably appropriate for the ground water at the site, there are issues related to ground water/surface

water interaction that makes designation of the TI zone problematic at this time. While ground water on-site could be addressed through appropriate institutional controls, it is unclear whether monitoring of the ground water/surface water interface alone provides sufficient protection of the creek. Therefore, since additional information and /or evaluation is needed to develop an appropriate remedy concerning the specific area of ground water which discharges to the creek, a ground water

remedy will not be included in this proposed plan. Part of the basis for a TI Waiver includes definition of the zone subject to waiver and verification that hazardous substances cannot migrate outside the defined zone. Once this additional information/evaluation is complete, then an appropriate remedy can be formulated

and proposed to the public.

SUMMARY OF SITE RISKS

As part of the 1991 RI/FS, a baseline human health risk assessment (BHHRA) was conducted to determine the possible effects of contaminants on human health and the environment. This risk

assessment premised the exposure setting characterization on industrial use as the future use of the Site, but evaluated a residential exposure scenario in case the Site became residential in the future. Given its historical use as a refinery for more than sixty years, its proximity to commercial areas of the City of Cyril,

and the abundance of undeveloped property available for future residential development, future commercial/industrial land use was assumed for ORC North in the SFS. Gladys Creek has been designated as a habitat-limited fishery and for usage as a secondary body contact recreational area by the Oklahoma Water

Resources Board Water Quality Standards (OAC 785:45). The original baseline risk assessment was conducted as part of the 1991 RI/FS. Certain aspects of the 1991 risk assessment were updated for the SFS. The SFS includes the same preliminary remediation goals for soils and sediments as the 1991 risk assessment. Ground water and surface water preliminary remediation goals were developed in the SFS even though the remedy in this proposed plan does not include ground water and surface water. The ground water and surface water goals will be re-evaluated during a future remedy process

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What are the “Chemicals of Concern”?

The DEQ has identified contaminants in soil, surface water, and sediment that pose the greatest potential risk to human health at this

Site. The occurrence of the adverse effects described below depends on the chemical concentration and level of exposure.

Metals: Metals are chemical elements that usually have luster, conduct heat energy and electricity, and bend without breaking. The following metals are contaminants of concern (COCs) at the site:

Arsenic and Lead: Arsenic and Lead are COCs for the soil, sediment, surface water, and ground water at the site.

Beryllium, Cadmium, and Chromium: Beryllium, Cadmium, and Chromium are COCs for the surface water and ground water at the

site.

Arsenic, Beryllium, Cadmium, and Chromium are known human carcinogens.

Volatile Organic Compounds (VOCs): VOCs are organic chemicals

that evaporate easily at room temperature. The following VOCs are COCs at the site:

Benzene: Benzene is a COC for the soil, sediment, and the

ground water at the site. Benzene is a known human carcinogen.

1,2 Dichloroethane: 1,2 Dichloroethane is a COC for the ground water at the site. 1,2 Dichloroethane is reasonably anticipated to be a human carcinogen.

Semivolatile Organic Compounds (SVOCs): SVOCs are organic

chemicals that evaporate slowly at room temperature.

Polycyclic Aromatic Hydrocarbons (PAHs): PAHs are a group of over 100 different chemicals that are formed during the

incomplete burning of coal, oil, and gas, garbage, or other organic substances like tobacco or charbroiled meat. PAHs are also found in coal tar, crude oil, creosote, and roofing tar. Benzo(a)pyrene and Benzo(b)fluoranthene are PAH COCs for soil and sediment

at the site . Benzo(a)anthracene is a PAH COC for soil at the site. Animal studies have also shown that PAHs can cause harmful effects on the skin, body fluids, and ability to fight disease after both short- and long-term exposure; however, these

effects have not been seen in people. PAHs are probable human carcinogens.

Base Neutral and Acid Extractable Compounds: Other base neutral and acid extractable compounds which are COCs for ground

water at the site include; 2,4 dimethylphenol, 2 methylphenol, and 2 methylnaphthalene.

Information from ATSDR ToxFAQs™ at www.atsdr.cdc.gov

concerning ground water and surface water at the site.

The human health risk assessment evaluated the potential for on- and off-site residential, on-site industrial, and on-site intruder populations to experience adverse health effects as a result of exposure to contaminants in soil, groundwater, surface water, sediment, and air. It was assumed that people could be exposed to site-related contaminants through dermal contact, ingestion, and inhalation.

The populations characterized for the risk assessment included current off-site adult and child residents, potential on-site adult and child residents, potential on-site adult trespassers, and potential on-site adult industrial workers. Chemicals of concern were identified for each medium based upon comparison to published screening levels from the USEPA. These Chemicals of Concern are shown in Table 2. Exposure to each chemical of concern was evaluated for potential non-cancer health effects, and for those chemicals that are potential carcinogens, having the potential to cause cancer. Risk of non-cancer health effects is determined by calculating hazard indices. The key concept here is that a "threshold level" exists below which non-cancer health effects are no longer predicted. The USEPA level of concern for non-cancer risk is a hazard index greater than one. The following populations had a calculated non-cancer hazard index greater than one:

Potential on-site worker with chronic exposure to surface soil (non-cancer hazard index: 1.2 as stated in the 1992 ROD)

Potential on-site adult or child resident with

direct exposure to surface water, surface soil, ground water, and on-site pond and pit sediments (non-cancer hazardous index: 87 as stated in the 1992 ROD)

The USEPAs target risk range for total excess lifetime cancer risk is 1 in 10,000 (10-4) to 1 in 1,000,000 (10-

6). The total excess lifetime cancer risks for the populations that exceeded the range were:

Potential on-site intruder with direct exposure to sediments ( cancer risk: 2x10-5 as stated in the 1992 ROD)

Potential on-site worker with chronic exposure to surface soil (cancer risk: 2x10-4

as stated in the 1992 ROD)

Potential on-site adult or child resident with direct exposure to surface water, surface soil, ground water, and on-site pond and pit sediments (cancer risk: 5x10-3 as stated in the 1992 ROD)

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Exposure to subsurface vapors by the vapor intrusion pathway was not considered in the 1991 RI/FS. Revising the existing risk assessment and transport model for vapor intrusion was not included in the scope of this SFS. It is assumed that vapor intrusion is possible given the amount of residual contaminants in the soil.

As part of the 1991 RI/FS, a site characterization and evaluation of endangered, sensitive and threatened species on and about the site was conducted to

determine if the ground water and soil contamination from the site and subsequent contamination of surface water is resulting in a significant adverse ecological impact. Potential environmental impacts cited include;: volatilization of aromatics into the air from soil and or water, release of nonvolatile compounds into surface water by ground water seeps and overland flow, and exposure of plants, insects, worms, and rodents to contaminants through soil and sediment. The evaluation concluded that the ponds located on or near the site (Whitefield and Brown Ponds) and Gladys Creek appeared to support a substantial, well balanced fish population. However, a stream survey for macroinvertibrates revealed less total numbers of individuals and greater difference in the number of individuals for a given species at sampling stations adjacent to the ORC Site immediately downstream from the acid and caustic seep areas. The RI/FS concluded, except in the acid and caustic seep areas, Gladys Creek was not significantly impacted by the ORC Site. It is the DEQ and USEPA’s current judgment that the Preferred Alternatives identified in this Proposed Plan are necessary to protect public health and the environment from actual or threatened releases of hazardous substances into the environment.

REMEDIAL ACTION OBJECTIVES (RAOs) RAOs are the cleanup objectives for protection of human health and the environment. Site-specific preliminary remediation goals (PRGs) for each COC are believed to provide adequate protection of human

health and the environment. RAOs and PRGs were developed for the site by medium. PRGS for soil and sediment are summarized in Table 3.

Because there are no Federal or State cleanup standards for soil contamination, the PRGs for soil and sediment at the site are based on the baseline risk assessment. The target risk level is 1 in

1,000,000 (10-6). Soil and sediment PRGs are based on future commercial/industrial land use of the Site. Areas of Concern (AOCs) are areas on-site that require remediation based upon the RAOs and PRGs. Areas of Concern (AOCs) by medium are shown in Figures 4 through 6. The RAOs for the site by medium are:

Surface Soil and Subsurface Soil

Prevent exposure to current and future human

receptors and ecological receptors through direct contact with, inhalation, and/or ingestion of contaminated soil that exceeds health based cleanup levels.

Prevent the migration of COCs from soil with

concentrations above ground water protection PRGs that would result in ground water contamination in excess of MCLs or site specific risk based levels.

On-site Pond Sediment Prevent exposure to current and future

human receptors and ecological receptors through direct contact with, inhalation, or ingestion of contaminated sediment that exceeds health based cleanup levels.

Prevent the migration of COCs from sediment

with concentrations above ground water protection or health-based PRGs that would result in ground water contamination in excess of MCLs.

Gladys Creek Sediment

Prevent exposure to current and future human receptors and ecological receptors through direct contact with and ingestion of contaminated sediment that exceeds health-based cleanup levels.

LNAPL Control exposure of current and future

human receptors through direct contact or ingestion of ground water contaminated with LNAPLs that exceeds health based cleanup levels.

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Control vapor intrusion from LNAPL in ground

water.

Reduce or eliminate the potential for ground water to be impacted by LNAPL contamination located in the subsurface.

A considerable amount of LNAPL could be removed using technologies proposed; however, a considerable percentage of LNAPL will remain due to low permeability and heterogeneity of the subsurface materials. The remaining quantity of LNAPL would be enough to provide a contaminant source to ground water for many years. Therefore there is a high degree of uncertainty whether the remedial approaches considered will provide remediation of the site in 30 years or less.

SUMMARY OF REMEDIAL ALTERNATIVES Remedial Alternatives for the ORC Site are presented below. A total of 13 remedial alternatives were evaluated. The alternatives are numbered to correspond with the numbers in the SFS Report. The net present worth cost calculations are based on a 7 % interest rate. A number of the Alternatives will probably take longer than 30 years to potentially achieve ARARs. A cost estimate for a 100 year period is included in the description of each alternative that is expected to take longer than 30 years to achieve ARARs. A summary of Remedial Alternatives is shown in Table 4.

The Preferred Alternatives for the Site are: • Soil and Sediment – Excavation and Disposal- Soil and Sediment Remedial Action Alternative 7C • LNAPL – LNAPL Recovery/Monitoring – LNAPL Remedial Action Alternative 6.

Common Elements The following paragraphs identify the common elements of the alternatives. All of the alternatives include site access controls including engineering controls and institutional controls.

Engineering Controls – Engineering controls include warning signs and fencing to limit access to impacted areas.

Institutional Controls (ICs) – The DEQ has filed a recordable notice of remediation taken pursuant to CERCLA in the land records of Caddo County. The notice contains a legal description of the affected property and identifies all engineering controls used to ensure the effectiveness of the remediation. Additionally, the notice contains a prohibition against engaging in any activities that could cause damage to the remedial action or to the engineering controls or that could cause recontamination of the soil or groundwater. The

notice contains appropriate restrictions on land use or other activities that are incompatible with the cleanup levels, including but not limited to restrictions against using groundwater for drinking. Implementation of updated institutional controls may be required with the selected remedy.

No Action Alternatives

Alternative 1: No Action Estimated Capital Cost: $0 Estimated Annual O&M Cost: $5,000 Estimated Present Worth cost: $11,868 Estimated Construction Timeframe: None

Regulations governing the Superfund program generally require that the “no action” alternative be evaluated to establish a baseline for comparison. Under this alternative, the DEQ and EPA would take no action at the site to prevent exposure to the surface soil, sediment, surface water, ground water, or visible wastes. Selection of the “no action” alternative would mean that the RAO’s would not be met and possible exposure of COC could occur to current and future human receptors and ecological receptors.

Soil and Sediment

Alternative 2: Limited Action Estimated Capital Cost: $0 Estimated Annual O&M Cost: $2,000 Estimated Present Worth cost: $39,168 Estimated Construction Timeframe: None

This alternative includes implementation of access controls and controlling surface ponding and drainage. Access controls include a fence and warning signs at the site boundary and ICs. A fence, warning signs and ICs are currently

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implemented at the site, therefore; these access controls would be maintained or updated. The ICs which are currently in place include a prohibition against engaging in any activities that could cause damage to the remedial action or to the engineering controls or that could cause recontamination of the soil or groundwater. The notice also includes restrictions on land use or other activities that are incompatible with the cleanup levels, including but not limited to restrictions against using groundwater for drinking. The current IC, which has been

implemented by DEQ, would remain in place, and updated ICs would be implemented by DEQ as required. The currently implemented IC is described in the common elements section above.

This Alternative does not provide for the treatment of identified soil contamination sources, and is expected to require annual operation and maintenance as long as wastes remain on-site. This Alternative is ineffective at achieving PRGs, but is intended to protect potential receptors by restricting access to contamination on the ORC site. Because waste would be left on-site, five-year reviews would be required.

Alternative 3: On-site Containment Estimated Capital Cost: $1,758,470 Estimated Annual O&M Cost: $14,577 Estimated Present Worth cost: $2,675,715 Estimated Construction Timeframe: 6 months

Alternative 3 is designed to protect potential receptors by restricting site access and controlling any off-site migration of contamination from ORC soils or sediments. This alternative consists of site access and surface drainage controls; neutralization of contaminated soils and sediments from the former acid and caustic pits; and containment and/or stabilization of contaminated surficial soils and sediments. Containment is the prevention of uncontrolled leakage of waste material by isolation of the waste using physical means. These physical means include capping, surface controls and dust controls for the purpose of minimizing risks to receptors due to physical contact with the waste material. Capping options include clay/soil cap or multimedia cap. The clay/soil cap option consists of placing compacted clay over the waste areas in sufficient thickness to create the necessary barrier. The multimedia cap option consists of a multi-layer cap made of soil and plastic liner material.

Stabilization would be utilized to reduce the potential for contaminant leaching into ground water.

Stabilization involves immobilizing contaminants in media by changing the material to a solidified matrix or inducing chemical reactions between the stabilizing agent and the contaminant to reduce contaminant mobility. A variety of materials can be used for stabilization including fly ash, kiln dust, lime, and Portland cement. Alternative 3 would comply with all of the identified ARARs, but it is unlikely that this alternative would achieve PRGs.

Alternative 4: Limited Treatment Estimated Capital Cost: $7,952,678 Estimated Annual O&M Cost: $19,826 Estimated Present Worth cost: $11,066,432 Estimated Construction Timeframe: 6 months

Alternative 4 is intended to provide limited treatment or stabilization of identified waste groups to minimize the potential for leaching of contamination to ground water or off-site migration.

This alternative consists of site access and surface drainage controls; neutralization of contaminated soils and sediments from the former acid and caustic pits; in-situ biotreatment of VOCs in soils; excavation and prepared-bed biotreatment (“landfarming”) of soils / sediments with organic contamination; and containment and/or stabilization of surficial soils and sediments with residual contamination (such as remaining metals) following treatment by other methods (such as after landfarming). In-situ biotreatment is implemented by introducing, injecting, or in-situ mixing of bacteria strains into soils or enhancement of indigenous bacteria to accelerate the biodegradation process. Prepared-bed biotreatment is implemented by placement of soils in a constructed prepared bed bioreactor followed by periodic mixing, churning, or tilling of soils to encourage biodegradation and possibly incorporation of added organic nutrients. Alternative 4 would comply with all of the identified ARARs; although it is unlikely that this alternative would achieve PRGs.

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Alternative 5: Site Treatment Including SVE Estimated Capital Cost: $7,170,650 Estimated Annual O&M Cost: $14,557 Estimated Present Worth cost: $10,776,001 Estimated Construction Timeframe: 8 months Estimated Time to Achieve RAOs: 30 Years

This alternative consists of site access and surface

drainage controls; neutralization of contaminated soils and sediments from the former acid and caustic pits; in-situ biotreatment of VOCs in soils; excavation and prepared-bed biotreatment (“landfarming”) of soils / sediments with organic contamination; and containment and/or stabilization of surficial soils and sediments with residual contamination (such as

remaining metals) following treatment by other methods (such as after landfarming). Additionally, this alternative proposes that subsurface soils be treated with an in-situ soil vapor extraction (SVE) technology, rather than excavation followed by prepared-bed biotreatment.

Alternative 5 is intended to build upon Alternative 4 by including SVE technology for the treatment of contaminants in subsurface soil. SS-5 includes in-situ treatment of subsurface soils with VOC and SVOC concentrations exceeding PRGs through the construction and implementation of an Air Sparging / SVE treatment system. Soil vapor extraction involves applying a negative pressure to the subsurface through a series of wells. These wells are connected to a vacuum blower which induces air flow from the surface atmosphere. This air transport causes volatilization of volatile organic compounds, which are then removed through the air stream. Released VOCs would be captured within the well and further treated by the remediation system or a biofiltration system before off-gassing.

Alternative 5 would comply with all of the identified

ARARs and the ORC site PRGs.

Alternative 6: Site Restoration Including Treatment by LTTD Estimated Capital Cost: $12,941,134 Estimated Annual O&M Cost: $15,465 Estimated Present Worth cost: $17,771,318 Estimated Construction Timeframe: 8 months

Estimated Time to Achieve RAOS: 30 Years

This alternative consists of site access and surface drainage controls; neutralization of contaminated soils and sediments from the former acid and caustic pits; in-situ biotreatment of VOCs in soils; and containment and/or stabilization of surficial soils and sediments with residual contamination (such as remaining metals) following treatment by other methods. Additionally, this alternative proposes that subsurface soils be excavated and treated with a LTTD technology, which is expected to minimize

any residual wastes.

Low temperature thermal treatment or low temperature thermal desorption (LTTD) is a method to separate volatile and semi-volatile organics from soils and sediments. Materials are heated between 90 and 320 degrees Celsius. The material is heated enough to cause desorption, but not incineration. The components in the soil are not damaged, which enables treated soil to retain the ability to support future biological activity. The desorbed contaminants are then collected and treated, burned or recycled. Two common thermal desorption designs are the rotary dryer and thermal screw. Rotary dryers are horizontal cylinders that can be indirect or direct-fired. The dryer is normally inclined and rotated. For the thermal screw units, screw conveyors or hollow augers are used to transport the soil through an enclosed trough. Hot oil or steam circulates through the auger to heat the soil indirectly. This process option is potentially applicable for ORC site soils where metals contamination is not a concern. Alternative 6 would comply with all of the identified ARARs and the ORC site PRGs.

Alternative 7: Excavation and Disposal Estimated Capital Cost: $6,840,381 Estimated Annual O&M Cost: $5,238 Estimated Present Worth cost: $9,673,068 Estimated Construction Timeframe: 1 year Estimated Time to Achieve RAOs: 1 year

This alternative consists of excavation and disposal of contaminated soils, and sediments.

Areas of surficial asphaltic waste have been visually identified on ORC North which comprise a total area of approximately 3.82 acres.

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These areas of surficial asphaltic waste will be sampled during the Remedial Design phase. If the RD sample results indicate constituents of concern above soil preliminary remediation goals, these areas will be included this Alternative.

Similar to the previous alternatives, site access and surface drainage controls are included. This alternative includes treatment if necessary and disposal. Possible treatment before disposal would include neutralization of sediments from the acid and caustic seep areas. For this alternative approximately 103,644 cubic yards of soil and sediment on the site would be excavated and disposed. The total volume of sediment to be excavated is 30,818 cubic yards.

Three disposal options were evaluated. Cost estimates for each option are detailed in the FS; for estimating purposes, the highest estimate is presented here. Each of the disposal options will comply with ARARs and site PRGs. The three disposal options evaluated include:

Disposal Option A – Excavated soils, and

sediments would be transported to and disposed in an off-site Subtitle D Landfill.

Disposal Option B - 13 % of excavated soils, and sediments, would be transported to and disposed in an off-site Subtitle C landfill. The other 87%

would be transported to and disposed in an off-site subtitle D Landfill.

Disposal Option C – Excavated soils, and sediments, would be disposed in the current on-site Hazardous Waste Landfill.

These disposal options would require 5-year reviews to ensure the remedy is protective.

After the contaminated soil, and sediment, is excavated, the excavated areas will be backfilled with clean soil and re-vegetated. The site will be

graded to ensure adequate surface water drainage through and across the site. Site grading will divert surface water drainage away from Cyril and into Gladys Creek. If the sediment becomes re-contaminated from ground water after remediation, and exceeds cleanup levels, a remedy will be selected in a future decision document.

Light Non-Aqueous Phase Liquid (LNAPL)

Alternative 2: Limited Action / MNA for LNAPL Estimated Capital Cost: $0 Estimated Annual O&M Cost: $2,000 Estimated Present Worth cost: $2,241,719 Estimated Construction Timeframe: None

Alternative 2 consists of site access and surface drainage controls, but does not implement any treatment of LNAPL. This alternative combines site access control with MNA. Site access control will be enforced using fencing, signs, and deed notices. While MNA is a passive remediation technique, this alternative is considered inappropriate for the treatment of LNAPL due to the necessary time frame for biological degradation of the LNAPL and the likely inability to stop off-site contaminant migration. MNA will not be relied on to reduce LNAPL.

Alternative 3: LNAPL Containment / MNA Estimated Capital Cost: $1,252,000 Estimated Annual O&M Cost: $64,600 Estimated 30 Year Present Worth cost: $4,850,159 Estimated 100 Year Present Worth cost: $5,314,125

Estimated Construction Timeframe: 3 months Estimated Time to Achieve RAOs: 100 Years

Alternative 3 provides a limited action alternative that attempts to control off-site migration of ORC site LNAPL. This alternative consists of site access and surface drainage controls; LNAPL monitoring and in-situ biodegradation by MNA; and containment of LNAPL through the use of ground water extraction wells or recovery trenches (where appropriate) at the perimeter of the site. This alternative is intended to provide a low initial capital approach to reducing the risk of off-site LNAPL migration.

Alternative 3 is not considered appropriate in the long-term due to the scale of the LNAPL plume and the difficulties involved in maintaining containment with varying lithologies and flow properties.

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Alternative 4: LNAPL Recovery / Multi-phase Extraction

Estimated Capital Cost: $2,890,000

Estimated Annual O&M Cost: $146,500 Estimated 30 Year Present Worth cost: $8,263,272 Estimated 100 Year Present Worth cost: $8,905,614 Estimated Construction Timeframe: 8 months

Estimated Time to Achieve RAOs: 100 Years

This alternative consists of site access controls; design and installation of LNAPL recovery wells; construction and operation of a LNAPL separation and treatment system; and disposal or recycling of recovered LNAPL waste. Alternative 4 provides a more active LNAPL recovery system than Alternative 3 in that all areas of identified LNAPL impact will be incorporated into the recovery system design, rather than just the site perimeter.

Vapor extraction or pumping wells will be installed in and around areas of LNAPL impact. Areas with

shallow LNAPL contamination may be evaluated for the installation of recovery trenches, if site conditions indicate trenches may be more effective than wells. Well density should be determined by conducting a pilot study to determine site-specific recovery efficiency and well radius of influence. The pilot study will be deferred until the remedial design phase.

Ground water will be pumped to the surface, where LNAPL will be separated.

This option requires the construction of an above-ground treatment system for recovered ground water with an oil/water separator and storage capacity for recovered LNAPL. Alternative 4 provides an active option for LNAPL removal; however, this type of pump and treat technology can often require long-term operation and maintenance where aquifer hydraulic conductivity is moderate to low.

Alternative 5: LNAPL Recovery / Aquifer Flushing

Estimated Capital Cost: $15,844,845 Estimated Annual O&M Cost: $16,100 Estimated 30 Year Present Worth cost: $23,731,076

Estimated 100 Year Present Worth cost: $24,277,877 Estimated Construction Timeframe: 8 months Estimated Time to Achieve RAOs: 100 Years

This alternative includes site access controls and a comprehensive approach to LNAPL removal. However, the aquifer flushing technology that is proposed by Alternative 5 is expected to be more effective at flushing LNAPL from within the aquifer pore space so that residual waste will be

minimized. This alternative also provides a more aggressive strategy for LNAPL removal that will reduce long-term operation and maintanence.

Injection (located primarily upgradient) and extraction wells (located downgradient and within the impacted area) will be installed to continually “flush” contaminated aquifer zones. Well density and design would be determined by site lithology, extent of

LNAPL impact, and/or site pilot testing. This option requires the construction of an aboveground treatment system for recovered LNAPL and ground water.

Treated ground water would be re-injected to maintain an aquifer flushing cycle. A properly designed solution of surfactants and/or oxidants would be injected through the formation to solubilize and mobilize the LNAPL so that it could be intercepted by the downgradient extraction wells. Surfactants selected would be food-grade, readily biodegradable compounds.

Alternative 6: LNAPL Recovery / Monitoring

Estimated Capital Cost: $357,541 Estimated Annual O&M Cost: $19,333 Estimated 30 Year Present Worth cost: $950,218 Estimated 100 Year Present Worth cost: $1,017,525 Estimated Construction Timeframe: 1

month Estimated Time to Achieve RAOs: 100 Years

Alternative 6 provides a cost effective method of LNAPL recovery to the extent practicable. As stated in the 1996 USEPA Guidance document,

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How to Effectively Recover Free Product at Leaking Underground Storage Tank Sites, LNAPL would be removed from the ground water until the performance standard (a threshold thickness of 0.1 foot of LNAPL, measured using an interface probe in monitoring or extraction wells) is attained. This alternative requires site access control measures including fencing and deed notices. For this alternative, recovery systems such as oil skimmers would be installed in the existing ground water

monitoring wells with the highest LNAPL thicknesses. The recovered hydrocarbon would be placed into a drum or tank for storage then disposed or recycled off-site. This alternative requires LNAPL monitoring during and after installation of the LNAPL recovery system. Alternative 6 provides a low initial capital approach to LNAPL remediation that would

target key areas of the plume; however, this alternative will require long-term operation.

A considerable amount of LNAPL would remain in the subsurface material due to low permeability and heterogeneity.

EVALUATION OF REMEDIAL ALTERNATIVES

Nine criteria are used to evaluate the different remediation alternatives individually and against each other in order to select a remedy. This section of the Proposed Plan profiles the relative performance of each alternative against the nine criteria, noting how it compares to the other options under consideration. The nine evaluation criteria are discussed below. The “Detailed Analysis of Alternatives” can be found in the SFS Report.

1. Overall Protection of Human Health and the Environment

All of the soil and sediment alternatives except the “no action” alternative and alternative 2 would provide some protection of human health and the environment.

Soil and Sediment

Alternative 1 and 2 are not protective of human health and the environment. Alternative 3 provides limited protection of human health and the environment. Alternatives 4, 5, and 6 provide protection of human health and the environment.

Alternatives 2 through 7 call for soil drainage and grading improvements to limit surface ponding and infiltration. All of the alternatives (except alternative 1) also continue the current site access control measures to limit exposure risks and revise the current deed notice as conditions warrant. Alternatives 3 through 7 include neutralization of sediments within the former acid and caustic pit seepage areas.

Alternatives 3 through 7 call for progressively

more protective remedial alternatives. Alternative 3 includes containment measures, such as surficial soil caps and in-situ stabilization of surficial soils and sediments. Alternative 4 provides minimal treatment of contaminated soil through in-situ biotreatment, excavation, and prepared bed biotreatment. Alternative 5

involves all of the components of Alternative 4, but provides more effective treatment of subsurface soils by installing an SVE remediation system. Alternative 6 builds upon Alternative 4, but proposes excavation and treatment by LTTD. Alternative 6 provides a more immediate and thorough destruction of contaminants than the

other remedial alternatives. Alternative 7 provides the removal of contaminants by excavation.

LNAPL All of the LNAPL alternatives except the “no action” alternative would provide some protection of human health and the environment. Alternative 1 and provides no protection for human health and the environment. Alternatives 2, 3, 4, 5, and 6 provide protection of human health and the environment.

Alternative 2 provides minimal protection by continuing site access control measures and MNA, which is considered ineffective treatment for LNAPL. Alternative 3 protects off-site receptors by attempting to capture and contain LNAPL before it leaves the site; but provides

minimal on-site protection. Alternatives 4 and 5 both provide for effective sitewide LNAPL extraction, although Alternative 5 is considered more protective of human health and the environment. Alternative 6 provides LNAPL recovery to the extent practicable in wells where LNAPL has been observed.

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2. Compliance with ARARS

Soil and Sediment

Since Alternatives 1 and 2 do not involve any active remediation, there are no applicable ARARs with

which these alternatives do not comply. Alternatives

1, 2, and 3 (and potentially Alternative 4) will not achieve PRGs. Alternative 3, 4, 5, 6, and 7 will meet all significant ARARs. Using Alternatives 3 through 6, a long period of time could be required to meet all significant ARARs.

LNAPL

Alternatives 1 and 2 fail to comply with all ARARs, specifically drinking water MCLs, Oklahoma Water Quality Standards, and site-specific PRGs (“to be considered”) will not be met. Similarly, since Alternative 3 relies upon MNA to biodegrade LNAPL

beneath the site, it is very unlikely that drinking water quality standards will be met.

Alternative 4 and 5 are both likely to comply with all of the identified ARARs, although Alternative 4 is expected to require a longer timeframe to complete. Alternative 6 does not comply with all of the ARARs.

3. Long Term Effectiveness and Permanence Alternatives 1 and 2 of all media do not provide any long-term or permanent treatment. Other than Alternative 1 (“No Action”), all of the alternatives for all of the media continue the current site access controls that have been implemented as an interim measure.

Soil and Sediment

Alternative 2 does not provide any long-term or permanent treatment. Alternatives 3 through 7 propose increasingly comprehensive treatment alternatives. The alternatives are also increasingly effective at reducing residual risks. Alternative 3 containment measures will leave wastes in-situ while decreasing their mobility; whereas Alternatives 4 through 6 propose active remediation technologies that will reduce waste volumes in varying rates through time. Due to complex subsurface conditions, Alternatives 3 through 6 may take longer than 30 years to achieve ARARs. Alternative 7 proposes the excavation and disposal of contaminated soil and sediments which greatly reduces residual risks.

Alternative 3 through 7 recommend re-evaluations of site access controls and the current deed notice as

site conditions change. By maintaining the deed

notice and site access controls, Alternatives 3 through 7 provide a long-term and reliable protection against accidental contact or exposure with on-site contaminants.

LNAPL

Alternative 2 does not provide any long-term or permanent treatment. Alternative 3 through 5 propose increasingly comprehensive treatment alternatives. The alternatives are also increasingly effective at reducing residual risks. Alternative 3 only attempts LNAPL removal near the site boundary, leaving the remainder in-situ. Alternative 4 uses physical extraction techniques (multi-phase pumping), but relies on biodegradation by MNA to remediate LNAPL that cannot be removed by pumping. Alternative 5 uses a combination of physical pumping and injected chemical solutions to minimize residual wastes. Alternative 6 provides a method for removal of LNAPL to the extent practicable, but residual LNAPL will be left on-site.

Alternatives 3 through 5 involve active remedial technologies that depend on adequate O&M to remain effective and reliable throughout the treatment process. Alternative 6 provides an effective method of LNAPL recovery which will require minimal operation and maintenance.

4. Reduction of Toxicity, Mobility, or Volume of Contaminants through Treatment

Alternatives 1 and 2 for soil, sediment, and LNAPL do not provide any reduction of toxicity, mobility, or volume of contaminants through treatment.

Soil and Sediment

Alternatives 3 through 6 include multiple treatment technologies that are increasingly comprehensive and thorough in scope. Alternative 7 includes excavation and disposal of 103,644 cubic yards of contaminated sediments and soils, which will greatly reduce the toxicity and mobility.

Alternatives 3 through 7 include neutralization treatment of soils and sediments in the former acid and caustic pit seepage areas along Gladys Creek. Alternative 3 also includes surficial

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capping and containment measures intended to reduce contaminant mobility; but does not include any additional measures to reduce contaminant toxicity or volume.

Alternatives 4 through 6 provide active treatment of all of the identified soil waste groups. Alternative 4 combines excavation with stabilization and biotreatment (“landfarming”) technologies to reduce contaminant toxicity and mobility. Alternative 5 builds upon Alternative 4, but reduces the volume of soil requiring excavation and disposal by proposing that subsurface soils be treated in-situ by SVE technology. Alternative 6 requires a similar excavation volume as Alternative 4, but further decreases the volume of residual wastes by proposing that highly contaminated soils be treated by LTTD. Alternative 7 requires excavation of 103,644 cubic yards of contaminated soil, and sediment, greatly reducing residual waste volume. The location of the material to be removed is shown in Figures 4 and 5.

LNAPL

Alternative 2 does not provide any reduction of toxicity, mobility or volume of LNAPL at the site. Alternative 3 is intended to prevent off-site mobilization of LNAPL and also reduces contaminant volume near the site boundary. Alternatives 4 and 5 provide sitewide remedies that are effective at reducing LNAPL volume and toxicity in addition to preventing off-site LNAPL migration. Alternative 6 provides an effective solution for reducing LNAPL volume and toxicity.

5. Short-Term Effectiveness

Soil and Sediment Alternatives 1 and 2 do not involve any construction and do not pose any short-term risks to workers. Alternatives 3 through 7 may pose short-term risks to workers during construction of remedial treatment systems, excavation activities, and/or waste handling activities.

The risks for each of the alternatives is expected to be minor and may be mitigated by conducting air monitoring, using safe construction and handling methods, and providing protective personal equipment when necessary.

LNAPL

Alternatives 1 and 2 do not involve any construction and do not pose any short-term risks to workers. Alternatives 3 through 7 may pose short-term risks to workers during construction of remedial treatment systems, excavation activities, and/or waste handling activities.

The risks for each of the alternatives is expected to be minor and may be mitigated by conducting air monitoring, using safe construction and handling methods, and providing protective personal equipment when necessary.

6. Implementability Alternative 1 for all media does not require implementation.

Soil and Sediment

Alternative 2 primarily continues the current site access control measures and is very easily implementable. Alternatives 3 and 4 involve active remediation technologies, but are all expected to be easily implementable. Alternatives 5 and 6 will require a more complex

series of remedial techniques, but are implementable with standard construction methods and detailed planning. Alternative 7 is easily implementable with routine earth moving and construction methods.

LNAPL

Alternative 2 primarily continues the current site access control measures and is very easily implementable. Alternative 3 and 4 involve active LNAPL pumping technologies, but are expected to be easily implementable with relatively routine construction methods.

Alternative 5 will require a more complex series of remedial technologies. Alternative 5 is implementable following a pilot study to determine aquifer flush solution chemistry and design. The pilot study will be deferred until the remedial design phase. Alternative 6 is easily implementable.

7. Cost The estimated costs are based on the best available data and are expected to have a degree of accuracy of +50% to -30% pursuant to USEPA guidance.

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Alternative 1 for all of the media provides no treatment, but will still require 5-year reviews at an estimated net present worth cost of $11,868.

Soil and Sediment

Annual inspections of site control measures bring the cost of Alternative 2 to $39,168. Alternative 3 provides minimal capping, containment, and maintenance of site control measures, and is estimated to cost $2,675,715. Alternatives 4, 5, and 6 provide increasing degrees of protection and are estimated to cost $11,066,432; $10,776,001; $17,771,318 respectively. Alternative 7 with disposal option A is estimated to cost $6,927,295. Alternative 7 with disposal option B is estimated to cost $9,673,068. Alternative 7 with disposal option C is estimated to cost $4,257,555. Cost savings from O&M and construction of the in-situ treatment in

Alternative 5 make it slightly less expensive than Alternative 4.

LNAPL

Alternative 2 is estimated to cost $2,241,719 for

LNAPL monitoring an access control measures alone. Alternative 3 provides limited treatment targeted at preventing off-site LNAPL migration and is expected to cost $4,850,159. Alternative 4 provides sitewide LNAPL extraction using multi-phase pumping and is expected to cost $8,263,272, although treatment may not be complete within the 30-year period.

Alternative 5 is expected to provide relatively timely and effective LNAPL removal for a cost of $23,731,076. Alternative 6 is estimated to cost $950,218 based on estimated costs for system installation, waste management, system O&M, LNAPL monitoring, conducting 5-year reviews, and periodic inspection and maintenance of site control measures.

SUMMARY OF PREFERRED REMEDIAL ALTERNATIVES

Soil and Sediment

Alternative 7C: Excavation of approximately 103,644 cubic yards of soil and sediment and disposal in the current on-site hazardous waste landfill.

This alternative is preferred because it is protective of human health and the environment, would reduce the volume and toxicity of soil and sediment

contaminants on-site, it is easily implementable, it is

cost effective, and it is expected to allow the property to be used for the reasonably anticipated future land use, which is industrial.

Light Non-Aqueous Phase Liquid

Alternative 6: Installation of LNAPL Recovery systems in existing wells with greatest LNAPL thickness for removal of LNAPL to the extent practicable and monitoring for thickness of LNAPL in wells.

This alternative is preferred because it is protective of human health and the environment,

it is easily implementable, it is a cost effective

method for removal of LNAPL, and it is expected to allow the property to be used for the reasonably anticipated future land use, which is industrial.

Based on the information available at this time, the State of Oklahoma and the USEPA believe the Preferred Alternatives would be protective of human health and the environment. The Preferred Alternatives can change in response to

public comment or new information.

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COMMUNITY PARTICPATION

The DEQ and USEPA provide information regarding the cleanup of the Oklahoma Refining Company Site to the public through public meetings, the Administrative Record file for the Site, and announcements published in the Cyril News. The DEQ and USEPA encourage the public to gain a more comprehensive understanding of the Site and the Superfund activities that have been conducted at the Site.

The date, location, and time of the public meeting, the dates for the public comment period, and the locations of the Administrative Record file, are provided on the front page of this Proposed Plan.

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Table 1: Chronology of Site Events

Date Event Description

July 1997 Baseline Field Investigation, Clayton

Ground water, surface water, and sediment samples were collected as part of the baseline field investigation prior to initiating remedial action

January 2002

Remedial Action Included remedial action construction activities and collection of numerous environmental samples for site characterization, geotechnical testing, air monitoring, annual ground water sampling, and postremediation verification sampling.

August 2003 Emergency Removal Action

Removal of hazardous substances including drums and lab equipment form ORC North

September 2003

Time Critical Removal Action

Included demolition of process equipment and an LNAPL investigation

May 2006 DEQ Gladys Creek Monitoring

Conducted sediment and surface sampling of Gladys Creek

February 2007

DEQ Gladys Creek Monitoring

Conducted sediment and surface sampling of Gladys Creek

March-June 2008

DEQ Phase 1 Assessment

The DEQ completed an investigation of surface soil, subsurface soil, sediment,ground water, and surface water to collect current analytical data to fill in data gaps pertaining to the nature and extent of contamination in soil

on ORC North, in ground water seeping into Gladys Creek, as LNAPL on ground water, and in ground water dissolved phase plumes. This Phase I data was collected to form the foundation of this SFS report to allow analysis of remaining ORC site contamination. Media sampled included surface soil, subsurface soil, ground water, surface water, and sediment.

July 2011 Conestoga Rovers & Associates Subsurface Investigation Report

A ground water study was conducted which included the measurement of water and LNAPL levels in existing monitoring wells and collection and analysis of ground water samples.

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Table 2: Chemicals of Concern

Type of

Compound Chemical

Metals Arsenic, Barium, Beryllium, Cadmium, Chromium,

Copper, Lead, Mercury, Nickel, Zinc

Volatile

Compounds

Benzene, 1,2-dichloroethane, Ethylbenzene,

Toluene, Xylene

Polyaromatic Hydrocarbons (PAHs)

Acenaphthene, Anthracene, Benzo(a)anthracene, Benzo(a)pyrene, Benzo(b)flouranthene,

Benzo(k)flouranthene, Benzo(g,h,i)perylene, Chrysene, Dibenzo(a,h)anthracene, Flouranthene, Flourene,

Indeno(1,2,3 cd)pyrene, Naphthalene, Phenanthrene, Pyrene

Other Base

Neutral and Acid Extractable Compounds

2,4-dimethylphenol, 2-methylnaphthalene, 2-methylphenol, 4-methylphenol,

Phenol

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Table 3: Site-Specific PRGs (mg/kg)

Sediments and Surface Soil for Industrial Reuse

COC Site Specific PRG Basis

Arsenic 25 HBR

Barium 13,500 HBR

Beryllium 2 2003 ESD Action Level

Cadmium 135 HBR

Chromium (Chromium III) 770 GW Protection

Copper 351,000 HBR

Lead 600 HBR

Mercury 81 HBR

Nickel 5,400 HBR

Zinc 54,000 HBR

Benzene 0.2 GW Protection

Ethylbenzene 191 GW Protection

Toluene 104 GW Protection

Xylenes 2,828 GW Protection

Acenaphthalene 4,424 GW Protection

Anthracene 55,752 GW Protection

Benzo(a)anthracene 4.1 HBR

Benzo(a)pyrene 0.33 Detection Limit

Benzo(b)flouranthene 0.69 HBR

Benzo(g,h,i)perylene 1,080 HBR

Benzo(k)fluoranthene 13 HBR

Chrysene 46 HBR

Dibenzo(a,h)anthracene 0.33 Detection Limit

Flouranthene 10.800 HBR

Flourene 8,888 GW Protection

Indeno (1,2,3/c,d)pyrene 3.2 HBR

Naphthalene 79 GW Protection

Phenanthrene 510 HBR

Pyrene 8,100 HBR

2,4 dimethylphenol 66 GW Protection

2 methylnaphthalene 510 GW Protection

2 methylphenol 12 GW Protection


Phenol 125 GW Protection

Subsurface Soils

Arsenic 305 GW Protection

Chromium 770 GW Protection

Lead 865 GW Protection

Benzene 0.20 GW Protection

Naphthalene 79 GW Protection

Phenol 125 GW Protection



2,4 dimethylphenol 66 GW Protection

2 methylnaphthalene 510 GW Protection

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TABLE 4: SUMMARY OF REMDIAL ACTIONS SFS Designation

Description

Soil and Sediment 1 No Action

2 Limited Action: IC & surface drainage controls

3 On-Site Containment: ICs, physical barrier or cap, in situ stabilization of soils, neutralization of soils and sediments

4 Limited Treatment: containment, stabilization, neutralization, excavation and prepared bed biotreatment

5 Site Treatment Including SVE: ICs, containment, stabilization, in situ biotreatment, neutralization, excavation and prepared bed biotreatment, in situ SVE treatment

6 Site Restoration Including Treatment by LTTD: ICs, containment,stabilization, in situ biotreatment, neutralization, LTTD Treatment

7 Excavation and Disposal: ICs, excavation, neutralization, disposal

Light Non-Aqueous Phase Liquid

1 No Action

2 Limited Action/MNA: ICs and MNA

3 LNAPL Containment/MNA: ICs, containment using ground water extraction wells or recovery trenches and MNA

4 LNAPL Recovery/Multiphase Extraction: Vapor extraction or pumping wells installed in

areas of LNAPL impact, ground water pumped to surface and LNAPL separated, requires above ground treatment system

5 LNAPL Recovery/Aquifer Flushing: injection extraction wells to flush contaminated aquifer zones, requires above ground treatment system

6 LNAPL Recovery/Monitoring: LNAPL Recovery systems installed in wells with greatest LNAPL thickness, monitoring for thickness of LNAPL in wells

028043

Cyril

Cyril Oklahoma Refining Company

.

Figure 2 - Site Location

OKLAHOMA

0 5,0002,500 Feet028044

FORMER WASTE SOURCE PIT (E.G.)

FORMER LEAKING TANK

(CURRENTLY EMPTY)

FORMER LEAKING TANK

(CURRENTLY EMPTY)

CLAY - DOMINATED ALLUVUM

WATER TABLE (PERCHED ZONE)

GLADYS CREEK LEGEND

SATURATED / UNSATURATED GROUNDWATER TRANSPORT OF CONTAMINANTS

DIFFUSION OF CONTAMINANTS IN CLAYS

LNAPL ( LIGHT NON-AQUEAUS PHASE LIGUIDS )

ZONE OF HYDROCARBON SATURATION

WATER TABLE

WATER

1

2

3

1

2

3

WATER TABLE (RUSH SPRINGS)

RUSH SPRINGS SANDSTONE

RUSH SPRINGS SANDSTONE

SLUDGE

GYPSUM

Figure 3 - Contaminant Sources and Potential Routes of Migration

028045

North ORC

South ORC

Figure 4 - Surface and Subsurface Soil Areas of Concern

LegendRailroad Track

Subsurface Soil AOC

N ORC & S ORC Boundary

Surface Soil AOC

ORC Site Boundary

Surficial Asphaltic Waste

.

Map created on12/11/2012.

0 500 1,000 1,500 2,000250Feet

028046

Caustic Seep(VOCs, SVOCs, Metals)

Acid Seep(VOCs, SVOCs, Metals)

North Gladys Creek(Metals)

Tanks 29 & 68 Ponds(Metals)

Railway Ditch(VOCs, SVOCs, Metals)

Figure 5 - Sediment Areas of Concern

. NORTH ORC

SOUTH ORC

LegendAOCORC Site BoundaryN ORC & S ORC Boundary Railroad Track

0 500 1,000 1,500 2,000Feet Map created on12/11/2012.

028047

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SGW-5 SGW-4IBB-3

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IBB-4

IBB-5

SBB-2

SBB-3

IBB-2

SBB-09

SBB-7

SBB-1

OSL-3 SBB-5

SBB-4

RMW-9

OSL-2OSL-1

RMW-6

SBB-6

SBB-28

SBB-22

RMW-4D

SBB-11

SBB-38

SBB-32

RMW-1D SBB-10

SBB-35

SBB-36

RMW-3S

RMW-2D

SBB-29

SBB-18

SBB-23

DLR-11

SBB-13

DLR-07DLR-05

DLR-03

DLR-04 DLR-01DLR-02

DLR-06

SBB-14

SBB-15

SBB-12

SBB-21

SBB-20RMW-2S

SBB-27

DLR-10

RMW-1S

SBB-37SBB-24 SBB-17

DOW-07

RMW-10

RMW-4SSBB-16

SBB-30

SBB-19

SBB-31

SBB-33SBB-34

SBB-25

Figure 6 - Combined Historic Apparent LNAPL Thickness

.

LNAPL Thickness (Feet)10+5-101-50-1ORC Site BoundaryN ORC & S ORC Boundary

@? LNAPL Monitoring Wells@A Ground Water Monitoring Well

0 200 400 600 8001,000Feet

North ORC

South ORC

Map created on12/11/2012.

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ACRONYMS

AOC Area of Concern

ARARs Applicable or Relevant and Appropriate Requirements

ATSDR Agency for Toxic Substances and Disease Registry

BLHHRA Baseline Human Health Risk Assessment

CERCLA Comprehensive Environmental Response, Compensation, and Liability Act

COPC Chemical of Potential Concern

COC Contaminant of Concern

DEQ Oklahoma Department of Environmental Quality

ESD Explanation of Significant Difference

FS Feasibility Study

ICs Institutional Controls

mg/kg Milligrams per kilogram

MNA Monitored Natural Attenuation

NCP National Oil and Hazardous Substance Pollution Contingency Plan

NPL National Priority List

O&M Operation and Maintenance

PRGs Preliminary Remedial Goals

ROD Record of Decision

RAOs Remedial Action Objectives

RI Remedial Investigation

RCRA Resource Conservation and Recovery Act

RME Reasonable Maximum Exposure

RSS Rush Springs Sandstone

Site Oklahoma Refining Company Superfund Site

SFS Supplemental Feasibility Study

SVOC Semi-Volatile Organic Compound

ug/L Microgram per Liter

USEPA United States Environmental Protection Agency, Region VI

028049


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VOC Volatile Organic Compound

GLOSSARY OF TERMS

Specialized terms used in this Proposed Plan are defined below:

Administrative Record – The body of documents available to the public associated with characterization and remedy selection at a site.

Applicable or Relevant and Appropriate Requirements (ARARs) – The Federal and State environmental laws that a selected remedies will meet. These requirements may vary among sites and alternatives.

Baseline Risk Assessment (BLRA) – An evaluation of the potential threat to human health and the environment in the absence of any remedial action.

Carcinogen – Capable of causing the cells of an organism to react in a manner to produce cancer.

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) – CERCLA was enacted by Congress on December 11, 1980. This law created a tax on the chemical and petroleum industries

and provided broad Federal authority to respond directly to releases or threatened releases of hazardous substances that may endanger public health or the environment.

Ecological Risk Assessment – Study that assesses risks to aquatic and terrestrial receptors posed by contaminant releases from a site.

Excess Lifetime Cancer Risk - Cancer risk posed by a contaminated site in excess of the lifetime probability of developing cancer from other causes.

Explanation of Significant Difference – Document required when the remedial action to be implemented differs significantly from the remedy selected in the Record of Decision with respect to scope, performance, or cost.

Feasibility Study (FS) – Identifies and evaluates the appropriate technical approaches and treatment technologies to address contamination at a site.

Groundwater – Underground water that fills pores in soils or openings in rocks to the point of saturation. Groundwater is often used as a source of drinking water via municipal or domestic wells.

Groundwater Monitoring – Ongoing collection of groundwater information about the environment that helps gauge the effectiveness of a clean-up action.

Human Health Risk Assessment – A study that determines and evaluates risk that site contamination poses to human health.

Institutional Controls – Actions taken to limit unauthorized access to the site, control the way in which an area of the site is used, and monitor contamination migration.

Microgram per Liter (µg/L) - A unit of measurement equivalent to one microgram of contaminant per liter of water.

Milligram per Kilogram (mg/kg) - A unit of measurement equivalent to one milligram of contaminant per kilogram of solid (typically soil).

National Oil and Hazardous Substance Pollution Contingency Plan (NCP) – Regulations governing cleanups under USEPA’s Superfund program.

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Preferred Alternative – Final remedial alternative that meets NCP evaluation criteria and is supported by regulatory agencies.

Present Value Cost – A method of evaluation of expenditures that occur over different time periods. By discounting all costs to a common base year, the costs for different remedial action alternatives can be compared on the basis of a single figure for each alternative. When calculating present worth cost for Superfund sites, total operations & maintenance costs are to be included.

Reasonable Maximum Exposure (RME) - The highest level of human exposure that could reasonably be expected.

Receptor – An organism that receives, may receive, or has received environmental exposure to a chemical.

Record of Decision (ROD) – A formal document that is a consolidated source of information about a Superfund site, the remedy selection process, and the selected remedy.

Remedial Action – Action(s) taken to correct or remediate contamination.

Remedial Action Objectives (RAOs) – Remediation objectives for protection of human health and the environment.

Remedial Investigation (RI) – A study conducted to identify the types, amounts, and locations of c=ontamination at a site.

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USE THIS SPACE TO WRITE YOUR COMMENTS

Your input on the Proposed Plan for the ORC Site is important to the DEQ and EPA. Comments provided by the public are valuable in helping the DEQ and EPA select a final cleanup remedy for the Site.

You may use the space below to write your comments, then fold and mail to Amber Brawdy at 707 N. Robinson, PO Box 1677, Oklahoma City, OK 73101-1677. Comments must be postmarked by February 22, 2013. If you have any questions about the comment period, please contact Amber Brawdy at (405) 702-5133, Michael Hebert at (214) 665-8315, or through EPA’s toll-free number at 1-800-533-3508.

Those with electronic communications capabilities may submit their comments to the DEQ or EPA via Internet at the following e-mail addresses: [email protected] or [email protected].

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Address ______________________________________________

City ______________________________________________

State _________________ Zip _________________________

028052

mailto:[email protected]

mailto:[email protected]

proposed plan oklahoma refining company superfund … · oklahoma deq 707 n. robinson, 6. th. floor...

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