Record of Decision; Safe Interim Storage of Hanford Tank Wastes, Hanford Site, Richland, WA

DEPARTMENT OF ENERGY

Record of Decision; Safe Interim Storage of Hanford Tank Wastes,

Hanford Site, Richland, WA

AGENCY: U.S. Department of Energy (DOE).

ACTION: Notice of record of decision (ROD).

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SUMMARY: DOE and the Washington State Department of Ecology (Ecology)

have jointly prepared the Safe Interim Storage of Hanford Tank Wastes

Final Environmental Impact Statement (SIS EIS) (DOE/EIS-0212) to assess

the environmental and human health impacts associated with the

construction and operation of facilities and systems to continue the

safe management of high-level, mixed radioactive wastes stored in tanks

at the Hanford Site. After careful consideration of environmental

impacts, lifecycle costs, public, agency, and tribal comments, and

engineering evaluations, DOE has decided to implement most of the

actions of the preferred alternative evaluated in the Final SIS EIS and

are documenting this determination in this

[[Page 61688]]

ROD. The actions will involve the continued operation of the existing

cross-site transfer system (ECSTS) until replaced by the construction

and operation of a new replacement cross-site transfer system (RCSTS)

consisting of buried, double-wall, insulated pipes, and continued

operation of the mixer pump installed in Tank 101-SY to mitigate the

unacceptable accumulation of hydrogen and other flammable gases.

Pending resolution of a recently identified safety issue, DOE is

deferring a decision on the retrieval of solids from Tank 102-SY, and

limiting the transfer of wastes through Tank 102-SY to non-complexed

wastes. Evaluation of this issue will be addressed under DOE's NEPA

procedures as necessary. DOE and Ecology have determined that new

storage tanks will not be necessary at the present time to mitigate the

flammable gas safety issue, based on the demonstrated success of the

mixer pump.

FOR FURTHER INFORMATION CONTACT: For further information on DOE and

Ecology activities related to this project or copies of the Final SIS

EIS, please contact:

Carolyn Haass, U.S. Department of Energy, PO Box 550, MSIN S7-51,

Richland, WA 99352, (509) 372-2731

Geoff Tallent, Washington Department of Ecology, PO Box 47600, Olympia,

WA 98504-7600, (360) 407-7112

For further information on DOE's National Environmental Policy Act

(NEPA) process, please contact: Carol Borgstrom, Director, Office of

NEPA Policy and Assistance (EH-42), U.S. Department of Energy, 1000

Independence Avenue, SW., Washington, DC 20585-0002, (202) 586-4600 or

(800) 472-2756.

SUPPLEMENTARY INFORMATION: DOE has prepared this ROD pursuant to the

Council on Environmental Quality (CEQ) regulations for implementing the

provisions of NEPA (40 CFR parts 1500-1508) and the DOE NEPA

regulations (10 CFR part 1021). The ROD is based on the analyses of

environmental impacts identified in the Final SIS EIS (DOE/EIS-0212);

consideration of project costs; compliance requirements for systems

involved in the handling, transport, and storage of high-level mixed

radioactive waste, and public, agency, and tribal comments.

Because NEPA and SEPA are very comparable in their purpose, intent,

and procedures, Ecology and DOE decided to prepare one EIS addressing

the requirements of both SEPA and NEPA. In February 1994, a memorandum

of understanding (MOU) was signed between the DOE, Richland Operations

Office and Ecology. The MOU called for the joint preparation of the SIS

EIS, the contents of which have been determined to satisfy both SEPA

and NEPA requirements.

Purpose and Need

DOE and Ecology identified the need to continue to provide safe

storage of high-level radioactive tank wastes while supporting tank

farm management and operations prior to implementing decisions made in

the ROD for the Tank Waste Remedial System (TWRS) EIS. The TWRS EIS is

evaluating the alternatives for permanent disposal of wastes currently

stored in tanks at the Hanford Site. To minimize the risk of managing

tank wastes prior to the TWRS ROD, a modern, safe, reliable, and

compliant replacement cross-site transfer capability is needed to move

wastes between the 200 West and 200 East Area tank farms. This transfer

capability is required because the 200 West Area has far less useable

double shell tank (DST) capacity than there is waste in single shell

tanks (SSTs).

The replacement waste transfer capability would provide the means

to move waste from the 200 West Area to the available DST capacity

located in the 200 East Area.

The ECSTS has been used to transfer wastes from the 200 West Area

to the 200 East Area for the past 40 years. This underground pipeline

system is at the end of its original design life. Currently, four of

six lines are out of service and unavailable to perform transfers due

to plugging. The two useable lines do not meet current engineering

standards such as, double containment and leak detection, required for

waste management facilities.

Based on current tank waste management and operation activities,

the SIS EIS addressed the need to do the following:

Remove Salt Well Liquids (SWLs) from older SSTs to reduce

the likelihood of liquid waste escaping from the corroded tanks into

the environment. Many of these tanks have leaked and new leaks are

developing in these tanks at a rate of more than one per year.

Provide ability to transfer the tank wastes via a

compliant system to mitigate any future safety concerns and use current

or future tank space allocations.

Provide adequate tank waste storage capacity for future

waste volumes associated with tank farm operations and other Hanford

facility operations.

Mitigate the flammable gas safety issue in Tank 101-SY.

Summary of Alternatives and Impacts

DOE and Ecology have identified four action alternatives in

addition to the no action alternative to satisfy the need to continue

to provide safe storage of high-level waste until decisions are made

based on the TWRS EIS. The alternatives consist of the preferred

alternative, truck transfer alternative, rail transfer alternative, and

new storage alternative. DOE evaluated the construction and operation

phases of each alternative to assess potential impacts to the following

environmental categories:

Geology, Seismology, Soils.

Population and Socioeconomics.

Water Resources and Hydrology.

Transportation.

Air Quality.

Land Use.

Radiation.

Cultural Resources.

Noise.

Health Effects.

Biological Resources.

The impact analysis showed that there would be no impacts related

to geology, seismology, water resources and hydrology, radiation,

noise, population and socioeconomics, or cultural resources for any of

the alternatives. Environmental categories where potential impacts were

identified are discussed under each alternative as applicable.

Preferred Alternative

The preferred alternative consists of the following components:

Construction and operation of the RCSTS for cross-site

transfer of SWLs, and 200 West Area Facility wastes from Tank 102-SY to

DSTs in the 200 East Area;

Construction of a waste retrieval system in Tank 102-SY to

retrieve solids;

Continued operation of a mixer pump in Tank 101-SY;

Transfer of liquid wastes through the ECSTS until the

proposed RCSTS becomes operational in 1998.

Transuranic solids from Tank 102-SY would be retrieved, transferred

via the RCSTS and consolidated in 200 East Area DSTs to provide space

for transfer of complexed SWLs. The consolidation of tank waste is an

ongoing tank farm management action evaluated under prior environmental

impact statements and a supplement (ERDA 1538, DOE/EIS-0063, DOE/EIS-

0113). Although such retrieval is addressed in the decisions resulting

from these NEPA documents, the retrieval of Tank 102-SY sludge was

discussed in the SIS EIS for a comprehensive consideration of impacts.

[[Page 61689]]

Impacts. Environmental effects identified under the preferred

alternative are primarily related to construction activities and

include impacts to soils, land use, and biological resources.

Construction of the RCSTS and associated facilities would disturb

approximately 30 hectares (74 acres) of land, none of which are

considered to be prime or unique farmland. Fugitive dust emissions are

anticipated during earth moving activities, but would be mitigated by

dust suppression measures.

Of the 30 hectares (74 acres) of land that would be disturbed while

constructing the RCSTS, approximately 9 hectares (23 acres) would be

mature sagebrush/cheatgrass habitat, a State designated Priority

Habitat and important habitat for the loggerhead shrike, a Federal and

State candidate species; the sagebrush lizard, a Federal candidate

species; and the sage sparrow, a State candidate species. The 9

hectares (23 acres) represents 0.01 percent of the total sagebrush

habitat at Hanford. The preferred alternative would include

establishing habitat restoration sites to mitigate the disturbance of

native soil and removal of vegetation in the construction area.

Truck Transfer Alternative

This alternative includes truck transfer of all wastes listed under

the preferred alternative, with the exception of solids from Tank 102-

SY which would not be retrieved under this alternative. Mitigation of

the Tank 101-SY safety issue by continued operation of the mixer pump

would also occur under the truck transfer alternative. The alternative

would transfer SWL from interim stabilization of 200 West Area SSTs and

200 West Area facility wastes to DSTs in the 200 East Area by truck,

without using Tank 102-SY as a staging tank for complexed wastes. The

SIS EIS evaluated the 3,800 liters (1,000 gallons) LR-56(H) truck and a

hypothetical 19,000 liter (5,000 gallon) tanker truck. The alternative

would utilize existing roadways and include construction and operation

of a new load facility in 200 West Area and an unload facility in 200

East Area, including underground transfer piping to and from the

facilities, and some additional roadway segments.

Impacts. Environmental effects from implementing the truck transfer

alternative include impacts to soils, transportation, and worker

health, due to the construction of load and unload facilities and

roadway segments, and operation of the truck transfer system.

Construction of the load and unload facilities and roadways would

disturb approximately 2 hectares (5 acres) of land, none of which is

considered to be prime or unique farmland, or mature sagebrush habitat.

During construction activities, dust suppression measures would be

implemented to reduce fugitive dust emissions.

The truck transfer alternative would use existing Hanford Site

roadways and new onsite road extensions to transport approximately 1.9

million liters (5 million gallons) of radioactive waste. Using the LR-

56 truck (3,800 liters (1,000 gallons) capacity), approximately 4,691

truck trips would be required over 1,564 working days assuming three

trips per day. If the 19,000 liters (5,000 gallons) capacity truck is

used, approximately 938 truck trips over 313 working days would be

required, assuming three trips per day. Potential traffic circulation

impacts could occur from barricaded roads, speed limitations, escorts,

and other administrative controls. However, based on a frequency of

three truck trips per day, shipping during off-peak hours, and

providing advanced notice of truck shipments, no significant adverse

traffic circulation impacts are anticipated.

Operators and health physics technicians would be exposed to

radiation within acceptable limits during operation of the load and

unload facilities. However, estimates for radiation dose to the truck

driver yielded an unacceptably high dose. Additional shielding analysis

or restrictions on the quantities of radioactive materials would be

necessary to ensure that radiation exposures would be as low as

reasonably achievable for the drivers.

Rail Transfer Alternative

This alternative includes rail transfer of all wastes listed under

the preferred alternative, with the exception of solids from Tank 102-

SY which would not be retrieved under this alternative. Mitigation of

the Tank 101-SY safety issue by continued operation of the mixer pump

would also occur under the rail transfer alternative. The alternative

would transfer salt well liquids from interim stabilization of SSTs,

and 200 West Area facility wastes by a hypothetical 38,000 liter

(10,000 gallon) rail car. The alternative includes use of existing

Hanford Site rail lines, construction and operation of some additional

onsite rail line segments, as well as construction and operation of a

new load facility in 200 West Area and a new unload facility in 200

East Area.

Impacts. Environmental effects associated with the rail transfer

alternative include impacts to soils and transportation. Construction

of the load and unload facilities and rail spurs would disturb

approximately 2 hectares (5 acres) of land, none of which is considered

to be prime or unique farmland, or mature sagebrush habitat. During

construction activities, dust suppression measures would be implemented

to reduce fugitive dust emissions.

Approximately 470 train trips, assuming one tank car per trip,

would be required to transfer the subject waste. Assuming 2 train trips

per day, 235 days would be required to transfer the wastes. The two

additional daily trips would not impact existing rail operations.

Significant impacts to road traffic from road closures during rail

transport are not expected because of advance notice of shipments,

restricting shipments to off-peak hours, and the short duration of road

closures.

New Storage Alternative

This alternative includes mitigation of the Tank 101-SY flammable

gas safety issue by dilution and retrieval of the waste. Facilities

constructed and operated to accomplish this action would include a new

tank facility (NTF), including two new DSTs and associated facilities,

a waste retrieval system in Tank 101-SY, a waste retrieval system in

Tank 102-SY, and the RCSTS. This alternative also includes transfer of

waste from Tank 102-SY, SWL from interim stabilization of SSTs in the

200 West Area, and transfer of 200 West Area facility wastes as

described for the preferred alternative. This alternative would provide

additional storage capacity that could be used for other future waste

management needs.

Impacts. Environmental effects identified under the new storage

alternative are primarily related to construction activities and

include impacts to soils, land use, biological resources, and worker

exposure. Construction of the RCSTS and NTF would disturb approximately

30 hectares (74 acres) and 20 hectares (50 acres) of land,

respectively, none of which are considered to be prime or unique

farmland. Fugitive dust emissions are anticipated during earth moving

activities, but would be mitigated by dust suppression measures. The 50

hectares (124 acres) of land would be a small incremental addition of

land committed to waste management at Hanford.

Approximately 30 hectares (74 acres) of mature sagebrush/cheatgrass

habitat would be disturbed from constructing the RCSTS and NTF. The new

storage alternative would include establishing habitat restoration

sites to mitigate the disturbance of native soil and removal of

vegetation in the construction area.

[[Page 61690]]

No health effects are anticipated for routine operation of any

facilities under the new storage alternative.

No Action Alternative

This alternative would not construct any new tanks, tank retrieval

systems, or cross-site transfer systems. The flammable gas safety issue

in Tank 101-SY would be managed through continued operation of the

existing mixer pump. The remaining supernatant in Tank 102-SY, SWLs

from interim stabilization of SSTs, and liquid waste from 200 West Area

facilities would be transported from the 200 West Area to the 200 East

Area via the ECSTS.

Impacts. There are no environmental impacts associated with normal

operations of the no action alternative. However, due to lack of

secondary containment and poor leak detection capabilities of the aging

ECSTS, leaks to the environment are considered more likely than under

the other alternatives evaluated in the SIS EIS. To avoid environmental

impacts from a failure of the ECSTS during waste transfer, operational

controls prior to waste transfers such as, pressure testing at levels

in excess of operational pressures, would be used to confirm the

integrity of the ECSTS before waste is introduced into the system.

Environmentally Preferred Alternative

Normal operations under the no action alternative would not result

in the loss of State-designated Priority Habitat, would not result in

the generation of additional contaminated materials requiring

decommissioning and disposal, and would not cause additional worker

exposures over existing levels, as would occur under the preferred,

truck transfer, rail transfer, and new storage alternatives. Therefore,

the no action alternative is considered the environmentally preferred

alternative under normal operating conditions.

However, because the existing cross-site transfer system is over 40

years old, there is a higher probability of system failure or an

accident than under the other transfer alternatives evaluated in the

Final SIS EIS. Additionally, because the existing transfer system is

not compliant with current engineering standards requiring double

containment and leak detection systems, there is a higher likelihood of

a release to the environment under accident conditions than would be

anticipated under the other transfer alternatives.

Other Considerations

In addition to the assessment of environmental impacts provided by

the SIS EIS, DOE and Ecology considered costs, comments on the Final

SIS EIS, and nuclear criticality safety in determining a course of

action to meet the need for interim management of Hanford tank wastes.

Costs

Comparative analysis of construction, operation, and

decommissioning costs among the alternatives was generated for an

interim period of five years and lifecycle operations till 2028. The

analysis was based on a comparable set of baseline assumptions

regarding waste volumes and transfer schedules, and accurately reflects

relative costs among alternatives. However, the estimates may not

accurately represent the true cost of implementing a specific

alternative once final decisions are reached on waste transfers. Based

on the unresolved criticality safety issues described below, retrieval

costs for solids removal from Tank 102-SY have been excluded from the

preferred and new storage alternatives. The results of the analysis are

as follows:

------------------------------------------------------------------------

Interim Lifecycle

costs costs b

Alternative (1995 (1995

dollars in dollars in

millions) millions)

------------------------------------------------------------------------

Preferred...................................... a $105.2 $243

Truck transfer................................. 125.9 632.8

Rail transfer.................................. 113.7 491.8

New storage.................................... a 328.1 589.6

No action...................................... 48.9 NA

------------------------------------------------------------------------

a Excludes costs for retrieval of solids from Tank 102-SY as proposed in

the SIS EIS.

b Includes costs for retrieval of solids from Tank 102-SY under all

alternatives.

The lifecycle costs for the no action alternative were not

estimated because the ECSTS could not meet waste transfer requirements

beyond the interim time period. All alternatives include a $36 million

decontamination and decommissioning cost for the ECSTS.

Comments Received

DOE and Ecology received comments from two individuals on the Final

SIS EIS.

Comment. One individual agreed with continued operation of the

mixer pump in Tank 101-SY to mitigate flammable gas accumulation.

Response. DOE will continue the operation of the mixer pump in Tank

101-SY.

Comment. ``The fundamental assumption is that the best way to

maintain Safe storage is to suck liquid waste out of single shell tanks

and then move it to a safer double shell tank. Why is that safer? A lot

of things can go wrong when you pressurize the waste and move it that

can't happen if you leave it in the single shell tanks. Look at the

spray leaks from your ITRS and PPSS that can kill hundreds of people.

Compare that to the lack of impacts to people if you leave the waste in

the single shell tanks as laid out in the Hanford EIS that produced the

empty grout vaults and the unbuilt vitrification plant. [Assumed DOE/

EIS-0113] Those facilities weren't needed either and the Department

rushed to the wrong decision spending millions of dollars

unnecessarily.''

Response. In the Record of Decision based on the Final

Environmental Impact Statement for the Disposal of Hanford Defense

High-Level, Transuranic, and Tank Wastes (HDW-EIS) (53 FR 12449), and

again in the Finding of No Significant Impact for an environmental

assessment for the Waste Tank Safety Program (DOE/EA-0915), DOE decided

to continue to safely store the SST waste prior to making a decision on

the disposal of this waste. The decision on the final disposition of

the SST waste will be made by the Department in the TWRS EIS. The SST

interim stabilization program is an ongoing program initiated in late

1970s to reduce the potential for release of high-level wastes into the

environment and allow continued safe storage of the high-level sludge,

salt cake, and non-pumpable liquid waste. Although no adverse

radiological impacts were postulated by the HDW-EIS for leaking SSTs,

including the ultraconservative 40,000 m\3\ (10.5 million gallons)

release scenario evaluated, DOE policy is to reduce the potential for

any liquid release whenever practicable [DOE/EIS-0113]. Further, all

retrievals and waste transfers will occur at subcritical levels in

accordance with existing procedures. There are currently 67 SSTs which

have been declared confirmed or assumed leakers. These SSTs have

released 2.3 to 3.4 million liters (600,000 to 900,000 gallons) of

waste to the environment. Therefore, it is DOE's policy that the

continued safe storage of the SST waste pending a final disposal

decision requires the continuation of the SST interim stabilization

program, which is scheduled to be completed by the year 2000.

The postulated spray releases from Initial Tank Retrieval System

(ITRS) and Past Practice Sluicing System (PPSS) evaluated in the Final

SIS EIS have a probability of extremely unlikely to incredible or 10-5

to 10-7 per year. When compared to the almost certain release to the

environment if liquid wastes are left in SSTs, DOE has determined that

the risks of transfer are

[[Page 61691]]

acceptable and that the risks to the environment from suspension of the

interim stabilization program are unacceptable.

Comment. ``What are the true impacts of leaving the waste in the

single shell tanks? Are they any greater now than they were in the old

EIS?''

Response. The SIS EIS is an interim action EIS which considers only

near term actions required to safely manage tank wastes until disposal

decisions are made through the TWRS ROD. Leaving waste in the SSTs is

beyond the scope of the SIS EIS. The TWRS EIS is currently re-

evaluating the consequences which would result from leaving wastes in

single shell tanks.

Comment. ``How much money will you waste this time on an action

that isn't needed?''

Response. The costs of the alternative actions are specified above.

DOE believes that the action is needed and the costs are justified.

Comment. ``Your purpose and need statement basically says you need

it because the State told you to do it in the TPA. So you already made

the decision in a fundamentally flawed way without regard to NEPA. Once

again the NEPA process at DOE is a sham . . . The bottom line is that

the DOE NEPA process is a sham, and now the State is a part of it. You

make decisions and then try to justify them with EISs.''

Response. This EIS was prepared to comply with the requirements of

NEPA. An EIS document identifies and evaluates the environmental

impacts of the proposed action and reasonable alternatives. The Tri

Party Agreement defines the schedules and milestones for taking certain

cleanup actions at the Hanford Site. The Tri Party Agreement is

annually revisited and can be changed if new information arises or

situations change. For example, the Tri Party Agreement had milestones

for the six new double shell tanks which were identified in Draft SIS

EIS. Public comments received on the Draft SIS EIS as part of the NEPA

process and new studies indicated that six new double shell tanks were

not needed. As a result, an adjustment to DOE's preferred alternative

was made in the Final SIS EIS and the Tri Party Agreement was modified

to delete the milestones for construction of new double shell tanks.

Comment. ``Even if you absolutely had to move some waste you

already have an existing pipeline system that can move liquids. This

year you moved over 400,000 gallons of waste through it. Why can't you

use it for more transfers? In fact your EIS says you plan to do just

that. For this EIS most of the waste is planned to go through the

existing pipelines. Why can't you send a few more transfers through the

existing lines? This would undoubtedly be cheaper and less damaging to

the environment. Before the last transfer the line was pressured tested

to make sure it would be safe. Why not just do that every time? You

could take very little risk by doing this and you'd save the people of

this country tens of millions of dollars.''

Response. The existing lines are planned to be used for liquid

waste transfers as indicated in the comment. However, due to the age of

the lines and likelihood of failure of these lines, DOE believes it is

prudent to replace these lines with a modern, safe, reliable and

compliant waste transfer system. This will provide DOE with a more

certain ability to meet its need for cross-site waste transfers.

Comment. ``A new line isn't needed just to move the amount of

liquid waste specified in this EIS. The State is making DOE build this

line to service the TWRS planned mission of vitrifying all the waste in

the tanks. If that's the true need, then this action needs to be

covered in the TWRS EIS where there might be a real need. Building it

for this trumped up need will prejudice the TWRS decision (which

already seems to have been made.)''

Response. DOE has a need to move waste cross-site prior to

implementing decisions based on the TWRS EIS. This need exists

independent of the decisions that may be reached based on the TWRS EIS.

The replacement cross site transfer system could become a component of

the TWRS, but DOE does not believe that its existence would be

prejudicial to any of the alternatives being considered within the TWRS

EIS.

Comment. ``How in the world can you be privatizing TWRS if you

haven't already made the decision?''

Response. Privatization of TWRS is not an action that was

considered in this EIS.

Tank Farm Criticality Control

Through an ongoing safety evaluation process, DOE recently

revisited its operational assumptions regarding the potential for the

occurrence of a nuclear criticality event during waste storage and

transfers. Changes to the Tank Farm Authorization Basis for Criticality

that were approved in September 1995, were rescinded by DOE in October

1995, pending the outcome of a criticality safety evaluation process

outlined for the Defense Nuclear Facilities Safety Board (DNFSB) on

November 8, 1995. Until these criticality safety evaluations are

completed, Hanford will operate under the historic limits which

maintain reasonable assurance of subcritical conditions during tank

farm storage and transfer operations. Of the actions evaluated in the

Final SIS EIS, only the retrieval of solids from Tank 102-SY is

affected by the technical uncertainties regarding criticality. Based on

the quantities of plutonium in Tank 102-SY sludge, retrieval of the

solids falls within the scope of the criticality safety issues which

will be evaluated over the next few months. As a result, a decision on

retrieval of solids from Tank 102-SY is being deferred in this ROD.

Tank 101-SY mixer pump operations, interim operation of the ECSTS,

operation of the RCSTS, SWL retrievals, and 200 West Area Facility

waste generation, would all occur within the applicable criticality

limits and would be subcritical.

Decision

Based on the consideration of environmental impacts, cost,

engineering standards, criticality safety, and comments received on the

Final SIS EIS, DOE will construct and operate the RCSTS on the proposed

route identified in the Final SIS EIS, continue operating the mixer

pump in Tank 101-SY, and transfer waste from the interim stabilization

program and other facility waste in the 200 West Area. During

construction of the RCSTS, SWLs and 200 West Area facility wastes will

be transferred through the ECSTS to DST storage in the 200 East Area.

These actions will provide safe, compliant, and reliable high-level

waste transfer capabilities and will operate with wastes at subcritical

levels under the existing Hanford Tank Farm Interim Safety Basis, until

final disposal decisions are made under the TWRS EIS.

The RCSTS will provide Hanford with a waste transfer capability

that meets current engineering standards for double containment and

leak detection. As compared to other transfer alternatives, the RCSTS

will:

More effectively minimize worker exposures and meet ALARA

requirements through remote operations and underground transfers;

Cost less during both the interim time period and less

over a lifecycle operation than the other action alternatives;

Provide greater operational flexibility by conducting

transfers that are independent of weather or site traffic;

More efficiently manage the transfer of millions of

gallons of wastes required in the near term and potentially required in

the future.

[[Page 61692]]

The RCSTS will be built on the proposed route identified in the

Final SIS EIS. Alternative routes evaluated in the EIS would have

environmental impacts identical to the proposed route except with

respect to impacts on Priority Habitat. The western segment optional

route would reduce habitat impacts by only 0.6 hectares (1.6 acres) but

at a significant cost increase. The eastern option would result in an

increase in habitat loss by 2.1 hectares (5.3 acres) over the proposed

route. Because habitat impacts will be mitigated, engineering siting

criteria are more favorable, and construction costs would be less, the

proposed RCSTS route is selected.

The continued operation of a mixer pump in Tank 101-SY is selected

to mitigate the flammable gas safety issue in that tank. The mixer pump

has been proven to be effective mitigation during more than one year of

operations. A replacement pump is available and will be maintained as a

contingency should the existing pump fail. Dilution as a mitigation was

not selected due to the success of the mixer pump, and because it would

increase waste volumes requiring new tanks for storage and generate

more waste for future disposal.

DOE will continue to use the ECSTS until the RCSTS is operational

to provide access to 200 East Area DSTs for storage of 200 West Area

facility wastes and retrieved SWLs. SWL retrievals will continue to

reduce the risk to the environment from leaking SSTs. Operational

procedures will assure the integrity of the ECSTS prior to any waste

transfers. The current planning base estimates that the ECSTS will

operate for approximately 625 hours during five transfers before the

RCSTS is operational.

Based on the new information available to DOE, since the issuance

of the Final SIS EIS, regarding nuclear criticality safety concerns

during retrieval, transfer, and storage actions, DOE has decided to

defer a decision on the construction and operation of a retrieval

system in Tank 102-SY. Pending the outcome of the technical initiative

to resolve the tank waste criticality safety issue, transfers of wastes

through Tank 102-SY will be limited to non-complexed wastes.

Mitigation

All practical means to avoid or mitigate environmental impacts from

the actions to be implemented by this ROD have been adopted by DOE.

With the exception of habitat losses and dust generation from

construction activities, and the potential to encounter cultural

resources during subsurface disturbance, all potentially significant

impacts have been avoided.

Construction of the RCSTS will result in impacts that can be either

avoided or minimized through the implementation of mitigation measures.

The surface and subsurface disturbance required for the installation of

the RCSTS, a 10 kilometer (6.2 mile) double-wall pipeline, has the

potential to affect biota, dust emissions, and cultural resources.

Biota will be displaced due to the loss of habitat. Particulate

emissions in the form of dust releases from exposed soils will occur if

not mitigated. Cultural resources may be encountered during subsurface

excavations necessitating mitigation actions.

Impacts to biota resulting from the loss of habitat will be

mitigated through a program of transplantation of mature sagebrush from

the RCSTS construction corridor to a mitigation site located in close

proximity to the impacted area. In addition, tublings will be

cultivated and transferred to the mitigation site. For the 9 hectares

(23 acres) of mature sagebrush lost to the RCSTS construction, 27

hectares (69 acres) of sagebrush habitat will be planted.

Dust emissions will be mitigated by a combination of watering and

reseeding of disturbed areas. In areas of active construction, water

will be applied at frequencies sufficient to prevent unacceptable

releases of dust. After RCSTS construction is completed, those areas

not required for routine access or maintenance will be reseeded with

native grass species.

No archaeological or historical sites were identified in the

corridor to be disturbed by RCSTS construction. However, one potential

archaeological site was identified within the compensation area to be

utilized for habitat mitigation. Impacts to this site will be mitigated

through avoidance. All ground-disturbing actions that occur during

RCSTS construction or habitat mitigation activities will be monitored.

A qualified archaeologist identified by DOE will assess the

significance of any resources uncovered. The archaeologist will

coordinate with DOE to initiate consultation with the State Historic

Preservation Officer (SHPO) and the appropriate tribal representatives,

including members of the Wanapum People, Yakama Indian Nation,

Confederated Tribes of the Umatilla Indian Reservation, and Nez Perce

Tribe. To the extent possible, all materials determined significant

will be avoided during subsequent activities and will be left in place.

If this is not possible, removal will be conducted in consultation with

DOE, the SHPO, and appropriate tribal representatives.

In accordance with Sec. 1021.331(a) of the DOE regulations

implementing NEPA (10 CFR part 1021), a Mitigation Action Plan (MAP)

will be prepared that addresses mitigation actions associated with the

course of action directed by this ROD.

Issued

The State of Washington concurred on this Record of Decision via

letter to the Department of Energy on November 21, 1995. This Record of

Decision for the Safe Interim Storage of Hanford Tank Wastes is issued

by the Department of Energy, Richland Operations Office, Richland,

Washington on November 21, 1995.

John D. Wagoner,

Manager, DOE Richland Operations Office.

[FR Doc. 95-29313 Filed 11-30-95; 8:45 am]

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