ML20198D014
| ML20198D014 | |
| Person / Time | |
|---|---|
| Issue date: | 03/28/1988 |
| From: | NRC |
| To: | |
| Shared Package | |
| ML20198D008 | List: |
| References | |
| REF-WM-3, TASK-TF, TASK-URFO NUDOCS 9801080113 | |
| Download: ML20198D014 (13) | |
Text
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IdAR t i 1986 DRAFT TECHNICAL POSITION INFORMATION NEEDS TO DEMONSTRATE COMPL!AhCE WITH EPA'S PROPOSED GROUNDWATER FROTECTION STANDAPCS IN 40 CFR FART 192, SUBPARTS A-C 1
INTRODUCTION
'his technical position provides guidance on the types of informatien and essessments that the NRC staff considers accept 6ble to demonstrate compliance with the EPA standard: for groundwater protection at inactive uranium mill tailings sites.
These stancards are contained in proposed revisions to Subparts A-C of 40 CFR Part 192 undet Title 1 of the Uranibm Mill Tailings Radiation Control Act of 1978 (UMTPCA), as amended.
Under Section 108 of LHTRCA and Section 275 of the Atomic Energy Act, remedial action taken by the U.S. Departnient of Energy (00E) must comply with these proposed standards untti EPA promulgates them in final form.
This technical position may be revised q
after EPA promulgates final standards for groundwater protection, wi The kRC staff will review the groundwater protection information and assessments subnitted by DCE in Remedial Action Plans (RAPS) using relevant procedures and acceptance criteria provided in Chapter 4 of the staff's Standard Review Plan for UMTRCA Title i Mill Tailings Remedial Action Plans (SRP).
The NRC staff intends to revise the SRP af ter EPA promulgates final groundwater protectiun standards for designated processing sites under Title I cf UMTRCA, Consistent with EPA's standards, the NRC staff distinguishes between groundwater protection aspects of the disposal of residual radioactive material disposal sites (either new sites or designated processing sites) and the at cleanup of existing groundwater contamination at designated processing sites.
Section 2 of this position describes the information and assessments that the NFC staff finds acceptable to demonstrate compliance with the disposal standards in Subparts A and C of 40 CFR Part 192.
Section 3 describes the
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inforrcation and assessments that the NRC staff finds acceptable to demonstrate
~
compliance with the groundwater cleanup standarcs in Subparts B and C of Part 192.
The final section describes the assessments and information that can be used to justify application cf supplemental standards in lieu of the standards in Subparts A and B, and to select apprcpriate remedial activities to demonstrate compliance with alternative supplemental standards.
2 DISPOSAL AND CONTROL OF RESIDUAL PADI0 ACTIVE MATERIAL EPA's proposed standards in Subparts A and C of 40 CFR Part 192 require information and a s ses sn.ents to demonstrate that the disposal of residual radioactive material complies with site-specific groundwater protection and clnsure performance standards.
The information and assessments needed for each site can be categorized into four components: (1) the groundwater protection standard, (2) a performance assessment, (3) a closure performance standard, and (4) a monitoring and corrective action program.
The purpose of the groundwater prctection and closure performance standards is to establish the minimum acceptable performcnce of the disposal and control of residual radioactive material in preventing or controlling future releases of hazardous constituents.
The monitorirg and corrective action program provides the basis 9001000113 080329 PDR WASTE WM-3 PDR 1
for the performance assessment, confirms the acequacy of disposal units, and provides for corrective actions that may be recessary if disposal units ao not perform adequately.
2.1 GROUNDWATER PROTECTION STANDARD EPA's standards in 40 CFR Part 192.02(a)(3) require that disposal units be designed to c m,rol residual radioactive material in conformance with site specific graundwater protection standaros established under 40 CFR Part 264.92 95.
The groundwater protection standard applies tu the uppermost acuifer hydraulically downgracient from the disposal uhit for residual radioactive material.
The NPC staff considers that the definitions of uppermost aquifer and aquifer provided in Appendix A to 10 CFR Part 40 should be used to impler:ent the groundwater protection standards in 40 CFR Part 192, Subparts A-C to maintain consistency betwecn groundwater protection programs at inactive and active uranium mill sites.
An aquifer is defined as a geologic formation, i
~~N group of formations, or part of a formation capable of (V
yielding a significant amount of groundwater to wells or springs.
The uppermost aquifer means the geologic formation nearest the natural ground surface that is an aquifer, as well as lower aquifers that are hydraulically connected with this aquifer within the boundary cf the site.
Any saturated zone created by uranium recuvery operations at cesignated processing sites should not be considered an aquifer unless the zone is or potentially is (1) hydraulically interconnected to a natural aquifer, (2) capable of discharge to i
surf ace water, or (3) reasonably accessible because of migration beyond the vertical projection of the t'cundary of land transferred for long-term government ownership and care [ Introduction to Appendix A of 10 CFR Part 40].
Groundwater protection standards consist of three components: (1) a list of hazardous constituents
(?) a corresponding list of concentration limits for the constituents, and (3) a point of compliance.
Although 40 CFR Part 264.92 provides for the establishment of the groundwater protection stancard only af ter hazardous constituents have entered the grouncwater from a regulated unit, the NRC staff ccrsiders that the groundwater protection standard should g) be established prior to construction of the disposal units to facilitate cesign and construction of the units in compliance with 40 CFR Part 192.02(a)(3).
For example, the staff consicers that hczardous constituents at cisposal sites can be identified prior to their detection in groundwater beneath the sites if they are reasonably expected to be in residual radioactive material and they are listed in Appendix VIII of 40 CFR Part 264 as amended by 40 CFR Part 192.
00E may propose groundwater protection standartis in the Remedial Action Plan for each disposal site considering characteristics of the esidual radioactive ruaterial, disposal unit design, hydrogeology, and other aspects that affect the hazaros posed by residual radioactive material to humans and the environment.
Upon approval of DOE's proposal, the NRC staff will concur with proposed groundwater protection standards anc specify the hazardous constituents, corresponding concentration limits, ano the poirt of compliance.
2.1.1 Hazardous Constituents Hazardous constituents should be selected based on DOE's characterization of the presence of listed constituents at designated processing sites.
Hazardous I
constituents shoulo satisfy the folicwing two criteria [40 CFR Part 264.93(a)]:
I
1 They are reasonably expected to be in ur derived frcm the residual radioactive material to be stabilized at the disposal site, and
- They are radium 226/228, uranium-234/238, nitrate, molybdenum, gross alpha particle activit or listed in Appardix VI!! of 40 CFR Part 261 (40 CFR Pt,*t 192.02(y,(3)(i)).
a)
Thus, hazardous constituents may include any of the 375 constituents listed in Appendix VI!! of 40 CFR Part 261, along with molybcenum, radium, uranium, nitrate, and gross alpha particle activity.
The addition of gross alpha to the list of potential ecostituents is considered by the NRC staff to be consistent with EPA's intent in providing a concentration limit for gross-alpha in 40 CFR Part192.02(a)(3)(ii).
DOE should identify hazardous constituents for each disposal site based on p
characterization of the composition of residual radioactive
- material, groundwater quality data, description of the processes ano reagents used in t
processing uranium, anc assessment of whether constituents are reasonably expected to be in or derived from residual radioactive material at the designated processing site.
Sections 4.2.2.1.1, 4.2.2.1.3, and 4.3.2.3 of NRC's SRP provide relevant acceptance criteria and review procedures for determining the extent and distribution of constituents in contaminated material.
2.1.2 Concentration Limits DOE should propose a enneentration limit for each hazardous constituent identified under 40 CFR Part 264.93.
These limits constitute maximum concentrations of hazardous constituer.ts that may not be exceeded in grounowater in the up:ermost aquifer hydraulically downgradient from the disposal unit.
As prov<ded in 40 CFR Part 264,94(a), the concentration limits may be established as either background concentrations, maximum constituent O
levels,.or alternete concentration limits.
For each hazardous constituent, 00E d
should provice a limit and the justification for its selection cs described below.
2.1.2.1 Background Limits DOE may propose background limits for hazarcous constituent concentrations in croundwaterintheuppermostacuifer[40CFRParts192.02(a)(3)and264.94(a)).
!ackground concentration is defined in this technical position as the observed concentration At the new disposal site where there is no pre existing contamination.
At designated processing sites where residual racioactive material will be stabilized
- onsite, background concentration is the concentration that would be expected in groundwater in the uppermost acuifer if contamination had not occurred at the site.
At new disposal sites. DOE may propose background concentration limits based on groundwater quality characterization information collected as part of the disposal site monitoring program (40 CFR Part 192.02(a)(3)(iv)].
At designated processing sites where contamination currently exists, DOE may propose background concentrations based on-groundwater quality characterization in adjacent areas that have not been af'ected by uranium recovery operations and on appropriate geochemical and hydrogeologic assessments of the processing site
[40 CFR Part
192.02(a)(3)(iv)).
For each proposed backgrcund concentration limit. DOE should submit sufficient information to demonstrate that the specified background concentration is representative of background groundwater cuality.
Such demonstrations should consider both temporal and spatial variability of groundwater quality based on analysis of site specific groundwater monitoring
- Sections 4.2.2.1.3 and 4.3.2.1 cf hRC's SRP describe information r. teds data.
1 and review procecures for determining beckground groundwater quality.
2.1.2.2 Maximum Constituent levels DOE may propose l'aximum Constituent Levels as concentration limits for hazardous constituents in groundwattr in the uppermost aquifer (40 CFR parts 192.02(a)(3) and 264.94(a);.
These levels are listed in Table 1 of this technical position.
00E does not neea to justify the limits in Table 1.
If a Haxirnum Constituent Level has not been established for a particular hazardous constituent, DOE should either propese a backgrcund limit under Section 2.1.2.1 or an ACL under Section 2.1.2.3 for that constituent.
O Tabie 1.
saximum Constitueat teveis for nazardous Constituents (40CFRParts192.02(a)(3)and264.94(a))
C_cnstituent flaximum Con _centratioli Arsenic 0.C5 mg/l Barium 1.0 mg/l Cacmium 0.01 mg/l Chromium C.05 mg/l Cross-Alpha Particle Activity (ex Rn and V) 15 pC1/1 Lead 0.05 mg/l fiercury 0.002 mg/l Molybdenum 0.1 mg/l Nitrate 10 mg/l Selenium 0.01 mg/l O' -
Endrin 0.0002 mg/l Lindane 0.004 mg/l l'ethoxychlor 0.1 mg/l Radium-226/228 5 pC1/1
-Toxaphene 0.005 mg/l Uranium-234/238 30 pCi/1 2,4-0 0.1 mg/l 2,4,5 TP Silvex 0.01 mg/l P.1.2.3 Alternate Concentration Limits
' DOE may propose Alternate Concentration Limits (ACLs) for hazardous constituents in groundwater in the uppermost aquifer
[40 CFR Parts 192.02(a)(3)(v) and 264.94(a and b)).
For each proposeo ACL, DCE should demonstrate (1) that the hazardcus constituent wi'1 rct pose a substantial present or potential hazard to human health or the environment as long as the ACL-is not exceeded and (2) that the ACL is as low as reasonably achievable considering practicable corrective actions that cuuld be implemented to improve the perforniance of disposal units.
4
l Information needs for ACL applications are described in f4C's draf t Technical t
Position on Alternate Concentraticn Limits for Vraniun Mills (in preparation).
The ACL Technical Position provides guidance about the standard format and content for ACL applications at active ard inactive uranium mill sites and corresponding standard review procecures.
The ACL Technical Fcs4 tion has been develtpeo primarily for use at active uranium mills regulateJ under UMTRCA 1
l Title 11.
Use of the ACL Technical Position at inactive uranium sites is appropriate because the ACL provisions in 40 CFR Part 192.02(a)(3)(v) and 10 CFR Part 40, Appendix A, Criterion SB(6) are essentially identical.
2.1.3 Point of Compliance DOE should propose a polni of compliance for each disposal site (40 CFR Part 192.02(a)(3) and 264.95).
The point of compliance is a vertical surface that extends downward into the upperriost equifer along the hydraulically downgradient limit of the disposa; area, in general, the point of compliance concept is implemented by irstalling a series of monitoring wells along this h,
surface.
The disposal area contains disposal units for residual radioactive material as well as components of the engineered system that are intended to promote long term containment of the n,ateriai.
00E should select a point of compliance that is as close to the disposal area as practical and that provides access for monitoring groundwater quality without disturbing engineered i
components intended for long-term isolation of the residual radioactive l
material.
DOE's selection of the point of ecmpliance should include a i
demonstration that groundwater monitoring at the point of compliance will provide early warning of the release of hazardous constituents to the uppermost aquifer.
2.2 PERFOR!iA!!CE ASSESSMENT 00E should deroonstrate that the performance of the disposcl unit for residual radiunctive material will comply with the site-specific groundwater protection standard [40CFRPart192.02(a)(3)].
Such demonstrations should consist of (1) n an assessment of hydrogeologic characteristics of the site, (2) design analysis V
of the disposal unit, and (3) performance assessment of the disposal site.
DOE should provide an assessment of hydrogeologic characteristics of the disposal site that is sufficient to support analysis of dispcsel unit designs and performance assessment.
Site characterization shculd include determination of existing and anticipated rates and directions of groundwater flow and hazardous constituent transport in both the unsaturated and saturated zones.
Sections 4.2.2.1.3 and 4.3.2 of the SRP provide relevant guidance on the types of information and assessments that should be included in assessments of the hydrogeologic characteristics of disposal sites.
00E should also analyze the performance of the disposal unit design for groundwater protection and considtr relevant aspects of Stotechnical stability, erosion protection, and radon emission control.
The analysis should specify the design necessary to assure compliance with the groundwater protection stand 6rd.
The analysis should estimate the inventory of residual radioactive raterial and hazardous constituents to be disposed in the cisposal units.
The cesign analysis should also ccnsider (1) elimination of free liquids in residual radioactive material, (2) stabilization of residual radioactive material to a bearing capacity sufficient to support the final cover, and (3) infiltration of liquids through the cover into stabilized residual radioactive material excess of their spec [ific retention or40CFRPart192.20(a)(3)].
If tailings contain water in the tailings are slurried to a new
l location, DOE's design analysis should consider the perfortrance of a liner or an ecutvalent barrier in disposal unit designs to prevent contamination of grounc; ster (40CFRPart192.20(a)(2)].
Further. 00E shculd sufficiently assess the performance of the disposal site to demonstrate that dispesal units for residual radioactive material have been designed to assure that the groundwater protection stancard Will be tret.
Such assessments sbculd evaluate the distribution and amounts of precipitation, rates and distributions of infiltration into disposal u t.i t s,
rates and distributions of water exfiltration from disposal units, leaching of hazardous constituents from restoual radicactive material, transport of the constituents in the unsaturated zone hydraulically downgredient from the disposai unit, and transport of hazardous constituerts in the uppermost acuifer.
The performance assessment shoulc
?rovide estimated hazardous constituent concentrations in the uppermost acuifer downgradient frcm disposal units for the design life of the units (e.g.,
1000 years).
These estimates shculd be compared with concentration limits in the groundwater protection standard to temonstrate l
-compliance with 40 CFR Part 192.02(a)(3).
Sections 4.2.2.1.3 ard 4.3.2 of the
(
SRP provide additional guidance about the types of environmental transport assessments that shoulo be used to demonstrate satisfactory performance of oisposal unit designs relative to the groundwater protection standard.
2.3 CLOSURE PERFORMANCE STAT.DARD 00E should oemonstrate compliance with the closure performance standard by showing that the need for further maintenance of the dispcs&1 site has been minimized (40 CFR Part 264.111(a)), and that the disposal unit controls, minimizes, or eliminates releases of hazardous constituehts to groundwater, surface water, and the atmosphere to the extent necessary to protect human health and the environment (40 CFR Part 264.111(b))[40CFRPart192.02(a)(a)].
L0E's demonstration cf compliance with the long-term stability standards in 40 CFR Part 192.02(a) generally constitutes - compliance with the requirement for minimizing maintenance in 264.111(a).
00E should comonstrate that design features for groundwater protection do oct rely upon maintenance to assure pd compliance with groundwater protection stancards.
Demonstration of compliance with the groundwater protection standarc contitutes compliance with groune; water aspects of the cl0sure performance standard in 264.111(b).
Compliance with -the air and surface water aspects uf the closure performance standard in 264.111(b) will be reviewed on a case by case basis.
2.4 GROUNDWATER MONITORING AND CORRECTIVE ACTION PROGRAM DOE should describe an integrated groundwater monitoring prcgram to be conducted. before, during, and after ccer.pletion of the disposal action.
The purpose of this program is to demonstrate that initial performance of the disposal' unit ccmplies with the groundwater protection and closure performance standards under 40 CFR Parts 192.02(a)(3) and (4).
The monitoring program should be based in part on the results of the site-specific performance 6
assessment to assure that the progran is capable of monitoring critical aspects of site perfurmance and provirang early detection cf aberrant performance.
Such programs may include rnonitoring in the uriseturated and saturated Zones to demonstrate that initial perfornance of disposal units is acceptable and to confirm significant assumptions invoked in support of performance assessrenth.
The program should describe or incorporate by reference procedures for collecting, handling, and analyzing groundwater samples, as well as general characteristics of the progran such as the nurnber, locaticn, and types of nonitoring installations rronitcring f reciuercy; procedures for evaluating incnitoring results ar'd action leveis that rney trigger implementatiun cf more extensive monitoring or indicate the reed for further action.
The monitoring program should consider phased irnpiementation of more detailed monitoring that be necessary if monitoring data indicate aberrant performance.
The may cisposal site monitoring program should also be integrated, to the raximum extent practical, with centingent corrective actions for disposal units and
(]
cleanup activities as described below.
Sections 3. 3, 4.1, 4.2, 5.1, and 5.2 i
of HRC's " Draft Technical Positicn Pa per on Environmental Monitoring of Luw-Level Radioactive Weste Disposal Fac'lities" provide relevant guidance on the types of groundwater monitoring programs that should be developed to cemonstrate performance of disposal units.
DOE should provide an evaluation of alterrative corrective actions that could be impleniented if the disposal nionitoring program indicates that disposal units are not performing adecuately [40 CfR Part 192.02(c)].
Although the NRC staff realizes that corrective actions cannot be completely designed before contamination is detected, the staff censiders that DOE should consider whether currective actions would be effective in restoring performance of disposal units in accordance with the groundwater protection standaro and, as necessa ry, in cleaning up groundwater in accurdance with the groundwater cleanup standard as modified te apply at the disposal site.
DOE should consider reasonable failure scenarios of the disposal unit and deir.onstrate o
that corrective actions could be implemented no later than 18 n.ct:ths after a i) finding of exceedence of the groundwater protection stancard.
m 3 CLEAN Op AND CONTROL OF EXISTING CONTAMINATION The purpose of the groundwater cleanup evaluation is to demonstrate compliance with EPA's proposed standards in Subparts B and C of 40 CFR part 192.
L'nli ke the disposal evaluation, the cleanup defronstration focuses on cleaning up or otherwise controlling existing grounowater contarination at designated processing sites including vicinity properties.
The restoration evaluation consists of three components:
the groundwater cleanup standard, cleanup demonstration, and cleanup ronitoring program.
The standard specifies target concentrations for cleanup of hazarcous constituents in contaminated groundwater, whereas the cleanup demonstration shows how planned remedial action will attain the target concentrations.
The cleanup monitoring program defines the extent of groundwater contamination, provides feecback on the effectiveness of the cleanup program, and monitors compliance with the groundwater cleanup standard.
The NRC staff considers that groundwater cleanup may be deferred until after EPA proniulgates final grounowater protection standards provided that DOE a
cemonstrates that disposal may prcceed independently of cleanup.
Such demor..trations may be particularly cumplicated at designated processing sites where residual radioactive material will be stabilized onsite.
Nevertheless, the staff will review proposed disposal utivities at designated processing site: to ensure that they do not preclude or preernpt future cleanup activities j
to attain compliance with EPA's prososed standarcs in Subparts B and C of 40 CFR part 192.
Thus, disposal anc cleanup activities should be integrated unless 00E demcnstrates that disposal and cleanup may be evaluated said performed independently.
3.1 GROUN0 WATER CLEANUP STA W RD I
I DOE shoulo specify a groundwater cleanup standard for designated processing sites (40 CFR part 192.12(c)).
Analogcus to the groundwater protection standard for disposal
- sites, the groundwater cleanup standard specifies hazardous constituents and corresponding concentration limits.
The groundwater cleanup standard should be generally consistent with the groundwater protection Q
standard at sites where residual radioactive materials are being stabilized on V
site.
Upon approval of DOE's proposed cleanup standerc, the NRC staff will concur with the proposal and specify the groundwater cleanup standard, i
3.1.1 Hazardous Constituents DOE should identify hazardous constituents present in residual radioactive material, contaminated groundwater, and soils contaminated by releases from resioual radioactive material [40 CFR Part 192.12(c)).
This identification should be tased on a groundwater characterization program that adequately identifies the presence cf hazardous ccris tituents released from residual radioactive material f[ollowing 40 CFR Part 192.12(c)(1)].
Hazbrdous constituents should satisfy the three criteria
[40 CFR Parts 264.93 and 192.12(c)):
1.
They should be reasonably expected to be in or derived from residual radioactive material at the designated processing site.
2.
They shoulo b4 present in groundwater in the upperriost equif er at the designateo processin site as detected in site specific groundwater monitoring programs g 3.
They should be radium-226/228, uranium 234/238, nitrate, molybdenum, gross-alpha particle activity, or listed in Appendix VIII of 40 CFR Part 261.
In addition to site-specific characterization data, DOE may use information such as descriptions of milling processes to assist in the assessment of which hazardous constituents are expected to be in or derived from residual radioactive material at processing sites.
3.1.2 Concentration Limits Similar to the concentration limits established under the groundwater protection standard. DOE should specify a concentration limit for each hazardous' constituent [40 CFR Part 192.12(c)). The limits constitute maximum concentrations that shoulo r.ot be exceeded in grouncwater in the uppermost a
aquifer.
These limits may be proposed as backgrounc limits. Maximum Constituent levels, or ACLS as previous!y cescribed in Section 2.1.2 of this technical positicn.
00E should justify the selection of numerical values for the concentration limits.
Unlike proposals for ACLs at disposal sites proposals for cleanup ACLs should consider practicable corrective actions for, clear,up of contamir.ated groundwater.
3.0 CLEANUP DEMONSTRATICH DOE chould demonstrate that the proposed reedial action is sufficient to cleanup hararcous constituent concentrations to below limits established in the site. specific grourdwater cleanup standard (40 CFR Part 192.12(c)].
The den,cnstration should identify and assess alternative corrective actions for groundwater clearup and control, select feasible corrective acticns and provice a plan for implementing the actions to attain com>11ance with the groundwater cleanup standard.
The demonstration should descr< be the extent of
]
groundwater contamination due to releases from residual radioactive material k
prior to disposal under Subpart A of 40 CFR Part 192.
The demonstration shoula include identification and location of hazardous c.)nstituonts and assessment of the rate and direction of movement of contaminated groundwater (40 CTR Part 192.20(b)(4).
have been c)ontaminated with hazardous constituents becauseThe asse they may be a icng term source of contamination for groundwater.
DOE should also demonstrate that proposed cleanup activities are adequate to attain compliance with the grounowater cleanup standard.
The demonstration should include an assessment of the effectiveness and efficiency of selected cleanup activities in attaining compliance.
The demonstration should also cescribe the schedule ano steps necessary to cca:plete cleanup of contaminated groundwater at designated processing sites.
Planned cleanup activities should be integrated, to the maximum extent practicable with disposal activities.
The demonstration should consider future plume mov,ement, including evaluation p
of such processes as dilution, scrption, complexation, and precipitation.
v Sections a.2.2.4 and 4.3.5 cf the SRP provide relevant acceptance criteria and NRC staff review procedures for groundwater cleanup and control activities.
To accommocato cleanup activities. DOE may(40 CFR Part 192.12 propose to extend the remedial period by an amount not to exceed 100 years Based on EPA's definition of rer.edial period in 40 CFR Part 192.01(g), the NRC staff considers that the remeolal period extends from March 7, 1983, until COE's authority to conduct remedial action other than groundwater cleanu) activities expires under Section 112 of UMTRCA or as otherwise specified(1)y the U.S.
Congress.
In such proposals. DOE should osmonstrate that hazardous constituent concentrations will not exceed the limits specified in the groundwater cleanup standard at the end of the period, (2) institutional ccntrols will be implemented effectively to protect public health and satisfy beneficial uses of groundwater during the period, (3) affected groundwater is not currently and is not projected to become a source of supply for public drinking water subject to the provisions of the Safe Drinking Water Act, and (4) oisposal of residual radioactive raterials will be completed in com311ance with the standards in 40 CFR Part 192.02 within the time period specified by the U.S.~ Congress.
DOE should demonstrate that institutional controls will be effective in 3reventing exposure of human and environmental repulations (e.g., wildlife) to lazardous constituents and that the controls encompass the extent of groundwater that has been or may be contaminated in excess of the groundwater cleanup standard.
DOE should demcnstrate that the controls include menitoring programs that are sufficient to verify projections of plume rr.ovement and to determine when the controls sbculd be terminated.
In addition DOE should demonstrate that the controls will be enforced by a durable loca,l, state, or federal agency with sufficient authority and comitrent for enforcement.
Proposals to extend the remedial period shculo also demonstrate that affected groundwater is not, and is not projected to become, a source of supply for public drinking water subject to the provisions of the Safe Drinking Water Act.
The NRC staff considers that underground sources of orinking water constitute sources of supply of public drinking water under the Safe Drinking Water Act.
As defined in 40 CFR Part 144.3, an undergrcund source of drinking water is an aquifer or its portion that (1) supplies any public water system, or (2)
O coataia$ a 'uffici'at a'aatity of 9rooaawat'r to iura'r a aub'ic wat'r $vit'=
and currently supplies drinking water for human consumption, contains fewer than 10,000 mg/l total dissolvec solids, and has not been exempted under the procedures in 40 CFR Part 144.7 using the exemption criteria in 40 CFR 146.4 A public water system provides piped water to the public for human consumption and has at least 15 service connections or regularly serves an avera 25 individuals daily at least 60 days per year (40 CFR Part 141.2(e)ge at least
).
As provided in 40 CFR Part 146.4, an aquifer or any portion thereof may be designated as an exempted equifer if it (1) contains groundwater with a total dissolved solids concentration more than 3 000 mg/l and less than 10 and is not reasonably Maued to supply a,pubile water system or (2),000 mg/l does not currently serve as a souma of public drinking water and cannot now, and will not in the future, serve as a source of drinking water because the aquifer satisfies any of the following criteria:
-X A.
It commercially prcduces or can produce n.ireral, hydrocarbon, or U
geothermal energy resources.
B.
It is situated at a depth or location that makes recovery of water for drinking purposes economically or technoingically impractical.
C.
It is so contaminated that it would be economically or technologically impractical to render the water fit for human consumption.
D.
It is located over a Class 111 well mining area subject to subsidence or catastrophic collapse.
-3.3 CLEANUP MONITORING PROGRAM DOE should specify and implement a monitoring program adecuate to define the extent, of groundwater contamination by hazardous constituents from residual radioactive material, to assess the effectiveness of remecial action activities for groundwater cleanup and control, and to monitor compliance with the groundwater cleanup standard [40 CFR Part 192.12(c)(1)].
The secpe of the program shculd include ron M oring activities prior to, curing, and af ter completion of groundwater cleang and control activities.
The programs should l
w
4 be integrated to the maximum extent practical, with trenitoring programs to assess plume m,ovement and cttenuation thruughout the remedial priod [40 C Part 192.20(b)(4) disposal is in ac)cordance with g]roundwater prot and the programs to demonstrate that initial performance of standards (40CFRPart192.02(b).
The program should include an appropriate combination of groundwater rnonitoring, surface water tr.onitoring, and soil and sediment tr.onitoring te evaluate performanco of cleanup and control activities.
Program descriptions should detail or incorporate by reference procedures for collecting, handling, and analyzing monitoring samples, as well as the general characteristics of the monitoring programs such as the number, location, and types of monitoring installatiens; monitoring frequencies; procedures for evaluating menitoring results; and action levels that may trigger irnplementa tion of enhanced monitoring activities or revisions tu cleanup activities.
Sections 3.2 3.3, 4.1, 4.2, 5.1, and 5.2 of NRC's "Draf t technical Position Paper on, Environtrental Monitoring of tow tevel Radioactive Waste Disposal Facilities" provide relevant guidance about acceptable cleanup monitoring programs.
O 4 SurPttstatat Stier4R05 EPA's standards in Subpart C of 40 CFR Part 192 provide for implementation of suppleniental standards for groundwater protection in lieu of 'he standards in Subparts A or B if any of the folicwing criteria apply [40 CFR Part 192.21]:
1.
Remedial actions recuired to satisfy the standards in-Subparts A or 8 of 40 CFR Part 192 would pose a clear ano present risk of injury to worker s or to merrbers of the public, notwithstanding reasonable measures to avoid or reduce risk [ Injury Critericn].
2.
Groundwater cleanup under 40 CFR Part 192.12(c) or acquisition of nuterials recuired to control residual radioactive material under 40 CFR Part 192.02(a)(3) woulo directly produce environtrental harm that is clearly excessive compared with potential health benefits to persons livingonorrearsites[ExcessiveHarmCriterion].
3.
Groundwater cleanup at a designated processing site under 40 CFR Part 192.12(c) is technically impracticable frorn an engineering perspective [!mpracticability Criterion:.
4 Groundwater that has been or may be contaminated by hazardous constituents released from resioual radioactive material is Class !!!
[ClassIIICriterion).
00E may propose implementation of supplemental standards on a site-specific basis for groundwater protection if it determines that these criteria apply.
The proposal shculo demonstrate satisfaction of at least one of the criteria, propose supplerr. ental standards to be applied in lieu of the standards in Subpart A or B, specify the reraecial action proposed to conply with the supplemental stancards, and justify the selection of supplemental stardards and remedial action activities.
In all cases, rerr,ecial action to comply with supplemental standards should come as close to meeting the otherwise applicable standarc as is reasjnable under the circumstances.
If the Impracticability or Class 111 criteria apply 00E should also ensure that the proposed remedial action is sufficient to protect human health and the environment.
U
i The injury Criterion applies to both control of residual radioactive material s
and cleanup of contamir.ated groundwater uncer Subparts A ono B of 40 CFF. Part 192.
DOE's demonstration that the Injury critecico applies stould ider.tify ard assess the natur6 and aniount of the risk of irjuries to workers cr the general sublic that ray be associated with the perforrance of the reredial action.
00E's demonstration shculd consider implementation of reasonable measures that moy reduce or eliminate risks to we'kers and the public that are assuciattc with the performance cf the remedial action.
The Excessive Harm Criterion applies to groundwater cleanup activities under 40 CFR Part 192.12(c) and the acquisiticn of materials such as radon barrier or
'ilter materials required for disposal unoer 40 CFR Part 192.02(a)(3).
DOE's denionstra tion that the Excessive Harm Criterion applies may compare potential health benefits to be gained by disposal or cleanup with the environmental harm associated with the remedial action.
The comparison should consider implementation of casonable measures to reduce or limit harm associated with the remedial action.
A clear excess of environmental harm is that which is long term, manifest, and grossly disproportionate to health O
benefits that snay reasonabiy be expected from the rerudial action.
The NRC
\\
staff will assess the ccrparison of environinental harm and benefits 90 a site specific basis.
For application of the Excessive Harm Criterion, the staff considers long& term to mean longer than several decades.
The harm should also be readily apparent and reasonably predictable.
The comparison sbculd atten.pt to characterize potential harm and benefits using a consnon indicator, such as money or health effects.
00E should justify appropriate harm to-benefit ratios on a case s & cific basis.
Technical impracticability of grw,1dwater clear.up actions should also be determined on a case specific basis.
As discussed by EFA in the supplementary information that accompanies the proposed standards, impracticable means unable to be put into practice rather than cost effective 52FR36004).
Therefore, DOE may demonstrate the applicability of the Impr(acticability Criterion by showing its inability to implement cleanup activities rather than by comparing costs and benefits associated with alternative corrective actions.
O with respect to aapirins the class tit Cr4terica, DOE may eemonstrate thet aquiters or portions of aquifers that have been or may be contaminated with hazarcous constituents released from residual radioactive materdal are Class 111 grourdwater.
As-defined in 40 CFR Part 192.11(e), Class 111 3roundwater is not a current or potential source of drinking water because 1.
The concentration of total dissolved solids exceeds 10,000 mg/1; 2.
Widespread, ambient contamination unrelated in uranium recovery activities exists at the site and cannot be cleaned up using treatiner.t methods reasonably employed in public water-supply systems; or 3.
The quantity of groundwater available from the aquifer is less than 150-gallons per day.
DOE should compare background Total Dissolved Solids (TDS) concentrations in groundwater with the 10,000 mg/l TDS limit in the definition.
With respect to the second part of the cetinition, DOE should demonstrate that existing natural or anthropic contamination unrelated to uranium nilling has caused increases 12
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in constituent concentrations over a large area that wculd sufficienti) oiscourage use of the groundwater as a sourc6 of supply for public water systems.
The demonstration shculd consider the capabilities of treatment methods reasonably employed in current public water supply systems.
These methods are described in Section 4.6 of EPA's " Guidelines for Grctod Water Classification under the EPA Ground Water Protectico Strategy" (Final Orof t),
Decenter 1906.
DOE demonstrations relative to the productivity portion of the definition should consider production rates from representative domestic, municipal, agricultural, and industrial wells in the region surrouncing the cesignated processing site, 5 _ CONCLUSION Under Section 108(a)(3) of the Urar. fur.1 hill Tailings Radiation Control Act of 1978, as amenced, and Section 175(a) of the Atomic Energy Act of 1954, amended DOE's remedial action project at designated processing sites shotic as comply with EPA's proposed grouncwater protection stancards in Subparts A C of 40 CFR Part 19E, until EPA promulgates the standards in final form.
DOE can O
demonstrate compliance with the standards by submitting the information and assessments described in this technical position in Remedial Action Plans for V
oesignated sites.
NRC staff will not concur, even conditionally, with DOE's proposed remedial action without demonstrations of compliance with the proposed groundwater protection standards.
However, NRC may concur conditionally with proposed remedial action if DOE demonstrates that groundwater protection activities at disposal sites can proceed independently of groundwater cleanup ectivities.
6 REF,ERENCES U.S. Envircrimental Protection Agency,1986, Guidelines on Ground-Water Classification under the EPA Ground Water Protection Strategy (Final Draft).
U.S.
Nuclear Regulatcry Commissien 1985 Standard Review Plan for UMTRCA Title 1 Mill Tailings Remedial, Action Plans:
Chapter 4, Water Resources Protection.
U.S. Nuclear Regulatory Comission, 1987 Draf t Technical Position Paper un Environmental Monitoring of low-level Radioactivo Waste Disposal Facilities.
U.S. Nuclear Regulatory Comission,1988, Draf t Technical Position on Alternate Concentration Limits for Uranium Mills (in preparation).
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