ML20247D896
| ML20247D896 | |
| Person / Time | |
|---|---|
| Issue date: | 07/24/1989 |
| From: | Fliegel M NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| To: | Lohaus P NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS) |
| References | |
| REF-WM-54, REF-WM-62, REF-WM-68 NUDOCS 8907250327 | |
| Download: ML20247D896 (14) | |
Text
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-1 QU{241?S MEMORANDUM FOR: Paul H. Lohaus, Chief Operations Branch Division of Low-Level Waste Management and Decommissioning, NMSS FROM:
Myron Fliegel Operations Branch Division of-Low-Level Waste Management and Decommissioning, NMSS
SUBJECT:
REPORTS OF VISITS'TO GREEN RIVER; RIFLE,'AND GRAND JUNCTION SITES' i
During the week of June 12, 1989, D.-Gillen,'T.. Johnson, M.-Weber'and I l-visited the subject sites for various purposes. We were accompanied by NRC consultant, Dr. Steven Abt, during the Green River and Rifle portions of the l
trip. Enclosed for your information are trip reports for.the Rifle and Grand l
Junction site visits, and an inspection report for the Green River
- j construction inspection.
l Original SP ; by
-l Wron H. F11egel
.q I
Myron Fliegel i
Operations Branch i
Division of Low-Level Waste Management and Decommissioning, NMSS
Enclosures:
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l ENCLOSURE 1
{
l On-Site Construction Inspection Report I
i Facility Name:
Green River Processing and Disposal Site Uranium Mill Tailings Remedial Action i
Project Site Green River, Utah Inspection Conducted:
June 13, 1989 NRC Personnel:
Myron Fliegel Ted Johnson Daniel Gillen Steve Abt, Colorado St. University Mike Weber Inspection Summary:
Area Inspected:
D. Gillen and M. Weber conducted.a routine, announced inspection including review of scope of construction activities, site condition, quality control records, and borrow sources..In conjunction with the inspection, M. Fliegel, T. Johnson and S. Abt observed alternate sources of rock riprap and bedding r.aterial at Freemont Junction, Hastings Pit, and West Bank.
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Details-I 1.
Persons Contacted.
- John Singleton, Site Manager, Morrison-Knudsen, Inc.
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- Steve Martz, QA Supervisor, MK Steve Dike, QC Level III Inspector, MK Dan Lewis, Site Engineer, MK Bob' Peel, Project M: nager, Jacobs Engineering
- Richard Richey, Project Manager, U.S. DOE j
- Chris Watson, Project Manager, U.S. DOE l
- Mark Day, State of Utah
- Larry Anderson, State of Utah i
1
- present at exit interview i
I
2 2.
Hastings Pit Borrow Source DOE plans to produce radon barrier and bedding materials from the Hastings Pit north of the Green River. site. The inspectors observed the physical characteristics of the radon barrier and bedding materials in situ, as well as a test pad, where the Remedial Action Contractor (RAC) mixed sodium bentonite into the radon barrier material. The radon barrier material is composed of calcareous silty clay that appears to have been deposited at the borrow pit by overland flow from outcrops of the Mancos Shale north and east of the pit.-
Shale fragments were not observed in-the silty clay, although the deposit contained minor discontinuous pockets of gravel and cobbles. The clay deposit is underlain by coarse gravels 'and cobbles of the terrace alluvium.from which the bedding material is to be obtained. The cobbles are well-rounded, up to 10 inches in maximum dimension, and mostly composed of competent sandstone' and limestone lithologies (see rock sources section).
3.
Processing Site / Disposal Site Inspectors observed general conditions of the processing site and the disposal cell for contaminated materials. The site loots clean 6nd orderly. The only construction activity observed during the inspection was the backfilling of the former tailings pond area with clean fill. A Quality Control inspector and field engineer supervised placement of the clean fill.
All contaminated materials have been placed in the disposal cell.
Placement of the radon barrier material on top of the contaminated enterials should begin within 2 weeks. The upper surface of the contaminated materials in the disposal cell appeared smooth, crusted, and stable. However, contaminated materials on the 2:1 slope were less dense, rutted, and less stable than on the 5:1 top sicpe. The RAC intends to apply a soil binder (CPB-12 vinyl acrylic copolymer emulsion) to reduce fugitive dust emissions from the disposal cel,1 before placement of the radon barrier. The contaminated materials are sandy, relatively homogeneous, and contain minor gravel, vegetation, and construction rubble (e.g., scrap steel). Some contaminated material has been aroded from the disposal cell and transported on top of the select fill-A layer in the trenches surrounding the d$sposal c=11 l
4.
Records Review l
Inspectors reviewed the following quality control records to ensure compliance with current versions of the construction specifications, Remedial Action l
Inspection Plan, and the Remedial Action Plan:
(1) comparisons of moisture content determinations (oven vs. microwave) for tailings, vicinity property material, radon barrier material, and Types A and B fills; (2) microwave / oven correlation and evaluation logs for general fill, contaminated material,.
subgrade material, special fills A and B,-and radon barrier material; (3) moisture content determinations for contaminated materials; (4) Quality i
Control Photograph Album; (5) frequencies and-results of density testing of I
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3 tailings /vp material- (6) frequency and results of moisture and density testing of buffer material; [7) frequency and results of gradation testing of buffer material;and(8)frequenciesofproctortests.
Review indicated that a sufficient number of correlations between microwave oven (ASTM D4643) and conventional oven (ASTM D2216) moisture content.
determinations were performed in accordance with the RAIP for materials that have'already been placed in the disposal cell. These correlations indicate that moisture contents from the two methods are comparable (within +/- 15).
Review indicated that a sufficient number of moisture content determinations and density checks were performed for. the contaminated materials placed in the cell in accordance with the RAIP.
Sample locations for density and moisture content deterininations were evenly distributed across the disposal cell, with at least 1 sample per quadrant for each lift. The average in-situ moisture content of the windblown and vicinity property meterial' complies'with Agreement Number-4 of the NRC-DOE meeting of April 5, 1989 based on review of-records CM-M-1 to -141~and CM-M-249 to -254. However, review of records CM-M-142 to -248 indicates that the average in-situ moisture content of the
. tailings does not comply with Agreement Number 4 of the NRC-DOE meeting of April 5, 1989. Based on these records and.the "information only tests," the average volumetric moisture content of the tailings is greater than 7%, which exceeds the limit by 25.
Review indicated that the buffer material was sufficiently tested for moisture, density, and gradation in accordance with the RAIP and SPECS.
The Quality Control Photograph Album is an effective technique to document progress in construction of the disposal cell. Similar photographic documentation should be considered for other UMTRAP disposal sites.
5.
Rock Source Observation Freemont Junction Mr. Johnson, Dr. Fliegel and Dr. Abt, escorted by the MK rock quarry technician, traveled to Fremont Junction, proposed source of the riprap rock for the slopes of the pile. The quarry is approximately 75 miles west of Green River, Utah.
Several sections of the highway are currently under construction, Several portions which results in slow traffic and numerous delay)s.
of the highway appeared to be steep (approx. 6%. Concern we.s expressed by the State of Utah,- DOE, and MK personnel as to the safety hazards and potential dangers of the haul route. The NRC staff expressed the opinion that the haul ~ route will require the drivers to be experienced, have good equipment and exercise good judgment. Also, vehicle check stations and/or rest stops located at
4 or near steep gradients would be advantageous for safe haul operations. At the Fremont Junction quarry site, the NRC staff were met by Mr. Larry Anderson, S', ate ~of Utah, and Mr. Richard Richey, and others to observe the rr,ck source / quarry. The staff observed
~ hree test pits and two rock stockpiles.
t The rock is primarily a hydraulically-placed volcanic derivative embedded with conglomerate materials. The rock layer was 5-12 feet below the ground surface, in most cases. The MK technician indicated that overburden materials will be stripped and the rock layer exposed. Rock material will be mined, placed on an 8" grizzly and crushed. All material falling through the' grizzly will' be discarded. The usable, crushed materials will be checked for -
consistency, size and gradation..It is anticipated that the poorer quality rock will be pulverized in the crushing operations. DOE and MK propose that rock size and gradation again be checked at the quarry during loading-operations and spot-checked at the disposal site prior to. placement.
s The rock at Fremont Junction has been tested for quality and durability and scored an 80. Based upon the rock durability score and visual examination, the rock source at Fremont Junction appears to be acceptable. However, seams of very poor conglomerate rock were found at the quarry site, and it appears that care should be exercised to insure that only good rock is produced.
West Bank The staff traveled to the Westbank rock quarry, located near the disposal site. Mr. Anderson (state of Utah), Mr. Richey (DOE),
Mr. Singleton (MK), and others were also in attendance. - The Westbank quarry site appeared to be characterized by an abundance of poor grade calcitic' limestone. The rock could be indented and pulverized with little effort.
Mr. Anderson indic'ated that the rock scored only a 48 but that'it was acceptable to the State of Utah. The NRC staff indicated that the rock did not appear to be acceptable for long-term stabilization of the disposal site.. Mr. Singleton expressed that the good seams of limestone.might be acceptable if quarrying operations could separate the good from the poor. quality stones. ' Mr. ' Johnson.
indicated that: a) if _the good rock' achieved a score of 50 b)if the good rock could be separated from the poor rock,'and c),if enough rock is available to warrant quarrying: operations,-the Westbank quarry could be re-evaluated, should DOE propose to do so.
= _ _ _ - _ _ _ _ _ _ _ _ _ _ _ - _ - _ _ _
5 Hastings Road The staff traveled to the Hastings Road quarry located northeast of the Green River site. The quarry is an alluvial deposit of rounded rock with rock sizes ranging up to approximately 8" in diameter.
DOE proposes that the rock be crushed, screened and placed as bedding material at the disposal site. The rock scored a 68 using the agreed-upon scoring procedure. The staff observed nothing which would indicate that the rock is not acceptable for use at the site.
j The rock may also be acceptable for use on the pile as erosion protection.
6.
Exit Interview The inspectors and other NRC staff and a consultant met with representatives of DOE, State of Utah, and the RAC at the conclusion of the inspection. The inspectors summarized the scope and findings of the inspection, as well as observations from the alternate rock sources at Freemont Junction, West Bank, and Hastings Pit as follows (signed observations attached):
l Issues frem Previous Site Visits N/A Observations:
o Visual check of rock at the Freemont Junction source affirmed that it is suitable for use as riprap at the Green River site, y
o Visual check of rock at the Hastings Road source indicates no reason to believe that it would not be an acceptable source of bedding material.
o Records indicate that the average moisture content (by volume) of the in-place tailings was approximately 7%. This represents an average 2% above the 5% agreed to in the 4/05/89 DOE /NRC 1
meeting. The final RAP should address the impact of this on compliance with the EPA groundwater standards.
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o DOE intends to apply a binder material for temporary stabilization of the in-place contaminated material. Although application may be necessary, DOE should consider potential I
effects on constituent releases to groundwater and address this I
in the final RAP.
o In general, remedial action at the Green River site appears to be progressing in an excellent manner, based upon site
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appearance, exceptional records management, record results, and j
site personnel.
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l ENCLOSURE 2 Trip Report for Site Visit to the Rifle UMTRA Site R1T le, Colorado Date:
June 14, 1989 Place:
Rifle UMTRA Site, Rifle, Colorado
Purpose:
Observation of Rifle processing site, proposed disposal site, and potential ro'ck sources in preparation for review of the 4
remedial action plan.
M. Fliegel NRC Consultant -
S. Abt Attendees:
NRC D. Gillen (Colorado St. University)
T. Johnson DOE - F. Bosiljevac -
J M. Weber S. Hamp 1
RAC -
B. Zebick TAC - B. Taber i
T. Goering
)
i Discussion:
'l 1
On the morning of June 14, 1989, NRC staff and consultant. Steve Abt observed the geological and hydrological characteristics.of the Estes Gulch proposed disposal-site for contaminated materials from the Rifle processing site.
NRC staff included Myron Fliegel, Dan.Gillen Ted Johnson and Michael Weber and were accompanied by Frank Bosiljevac (DOE), Steve Hamp (DOE),
BillTaber(TAC),andTimGoering(TAC). During the afternoon, NRC staff members Fliegel and Weber observed demolition and construction activities at the Old and New Rifle processing sites and several vicinity properties located in Rifle. B111 Zebick, RAC site manager for Rifle, hosted the observations of the processing and vicinity property sites. Concurrently, Gillen, Johnson and i
Abt visited the Rifle Gap and Glenwood Springs sources of rock erosion protection.
Estes Gulch NRC_ staff observed geographical, geological, and hydrological aspects of the Estes Gulch site located north of Government Road (Route Numbers 13 and 789) northwest of Rifle, Colorado. Following l
i a site orientation by Bill Taber, the NRC staff walked the entire site from the diversion-ditch area near the top of the basin to the toe ditch area along the south edge of the disposal sib. Staff member Weber observed and aided TAC hydrologist Tim Goering in measuring water levels in site monitoring wells. Most of the wells were originally dry when they were drilled. Water levels in several of the wells have been artificially elevated as a result of water added last year during constant head injection tests.
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i Vegetation includes small grasses and forbs, sage, and other plants
-characteristic of.the semi-arid Colorado Upland area. The ground surface is mantled with. calcareous sandy to silty clay soils. The
. soils appear to be relatively dry to a depth of at least 10 feet, as i
evidenced in cuts recently exposed in arroyos..The soils and i
underlying colluvial / alluvial deposits have been incised by steep arroyos that are actively eroding back towards the proposed disposal area. The easternmost arroyo on the disposal cell footprint has been dammed by an earth dam to form a stock watering pond downgradient of the disposal cell near.the power lines. During the site visit, approximately 1 foot of water was ponded in the.
stock pond. The increased availability of water near. the stock pond has supported increased growth of sage,' juniper, salt cedar, marsh grasses, and _other vegetation.
The site appears to be underlain.by steeply dipping, variegated shales, mudstones, siltstones, and sandstones of the Tertiary -
Wasatch Formation. This formation is exposed in the canyon west of the disposal. site. An abrupt change.in the orientation of the bedrock to a.more gentle dip is apparent in the eastern wall of the canyon west' of the disposal site in the southwestern quadrant of Section 14. This abrupt change may indicate the' presence of a fault or other structural' feature. DOE has constructed several monitoring wells along the trace.of this feature south of the disposal site to determine its effect on groundwater flow.
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Rifle Gap Rock Source NRC staff members Fliegel, Johnson, and Gillen and Dr. Abt visited the Rifle Gap quarry located.approximately 12 miles northeast of Rifle, CO. The quarry was primarily. limestone embedded with very 4
poor cong1cmerate material. The good limestone scored approximately I
70 for rock quality, according to Mr. Taber. The staff noted the l
1 presence of some apparently poor-quality rock which would probably need to be separated during quarry operations.. It appeared that adequate rock'is available.
l Glenwood Springs Rock Source i
Mr.. Johnson, Mr. Gillen and Dr. Abt accompanied Mr. Taber and Mr. Bos11jevac to the Glenwood Springs, C0 quarry located l
approximately 35 miles east of Rifle, CO. The proposed rock from this source is a limestone embedded with conglomerate materials.
Mr. Taber indicated that the limestone scored between 70-80 for rock
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quality. However, it appeared that careful supervision.and examination would be needed to separate the limestone.and conglomerate materials during quarrying and to assure that rock of i
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1
, l acceptable quality is produced. NRC staff recomended that if this quarry serves as the source of riprap for the Rifle disposal site, a comprehensive plan for separating good quality and poor quality rock materials should be formulated.
Processing Sites Bill Zebrick, RAC site manager, escorted NRC staff members Fliegel and Weber on a tour of the demolition and construction activities at the New and Old Rifle processing sites. NRC staff were also accompanied l
by Steve Hainp (DOE) and Tim Goering (TAC). After a brief tour of I
the contractor office's at the New Rifle site, NRC staff observed the waste water collection system between the tailings cell and Interstate 70, including an 0.8 million gallon retention pond snd lined collection ditches. The 30 mil PVC synthetic membrane. pond and ditches were lined with Staff also observed general demolition activities, including destruction of a large tank and l
superstructure that was once part of the solvent extraction circuit i
of the uranium mill.
The demolition activities are generating large l
volumes of contaminated rubble, which will be disposed of in the i
tailings disposal cell at Estes Gulch. The RAC has retained a subcontractor for removing and managing hazardous waste (e.g.,
vanadium oxide) and asbestos wastes.
Charles Siberling (RAC) sumarized the uranium and vanadium extraction circuits of the New Rifle mill. Mr. Siberling noted that Nacl was added to the crushed ore to facilitate metal extraction in i
the roaster. The mill also used ammonium sulfate for pH control.
Organics used in the process included kerosene, isodecanol, and l
tertiary amines; these organics were periodically decanted to 4
skimming ponds located to the east of the tailings pile. During the i
site visit, the RAC was irrigating the tailings pile to control fugitive dust emissions and promote vegetation.
Staff observed the Old Rifle processing site from the side of Route 6 without entering the site. During the site visit, the RAC was constructing a new entrance ramp to the site using clean fill, as well as a we:tc water collection and retention system and a decontamination pad with sumps. The waste water retention pond can contain about 0.75 million gallons and is lined with 30 mil PVC.
Contaminated foundation rubble has been excavated from the eastern l
portion of the site and stockpiled on the tailings. After the visit to Old Rifle, NRC staff observed cleanup and restoration activities at several private residences located on the bluf.f northwest of the Old Rifle site. These properties have been contaminated by windblown contamination from the site. Restored properties appeared neat and orderly compared with properties that have not yet been cleaned up.
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l ENCLOSURE 3 Trip Report for Site Visit to the Grand Junction UMTRA Site 1
j Grand Junction. colorado Date:
June 15, 1989 i
Place:
Grand Junction UMTRA Disposal Site f
Cheney Reservoir, C0 i
Purpose:
Observation of Grand Junction Cheney Reservoir disposal site and recently constructed site characterization trenches in j
preparation for review of the remedial action plan.
' l Attendees:
NRC: M. Fliegel DOE: J. Szenasi*
TAC: K. Agogino*
D. Gillen M. Matthews*
L. Koons T. Johnson
-L.'Damler*
3 M. Weber-D. Leske St. of Colorado:
S. Hamp.
P. Oliver BLM: B. Fowler
- RAC: J. Heitkamp
-Wn Nagle*
P. Martinek j
- Did not participate in staff observations of site and surrounding area i
Discussion:
On June 15, 1989, NRC staff members Fliegel, Gillen, Johnson.-and Weber i
observed the proposed tailings disposal site located near Cheney Reservoir east of Grand Junction, Colorado.
The primary purpose of the site visit was to observe and assess the extent of perched groundwater in shallow terrace alluvium and golluvium beneath the site and above the Mancos Shale.
1 DOE is conducting a comprehensive hydrogeologic characterization program to assess the perched groundwater, including excavation of large exploratory trenches.
I electromagnetic terrain surveying, infiltrometer testing, tracer. testing, drilling, coring, and monitoring well installation.
NRC staff members observed geographical, geological, and hydrogeological characteristics of the Cheney Reservoir disposal site along a traverse from the southeastern corner of Section 11 (T35, R2E), to the southwestern corner of Section 12, to the center of Section 12, northwest to the southeastern corner of Section 2, to the center of Section 11, and back to the southeastern corner of Section 11.
In the af ternoon, NRC staff members Weber and Gillen also observed site characteristics in the three trenches constructed on the 2
disposal site and along a traverse along the escarpment southwest of the site
.from the center of Section 15 (T35 R2E) to the center of the southern boundary of Section 14.
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1 The site is located on a gently sloping pediment surface.
Soils are sandy to l
silty, dry, and armored with basalt cobbles and gravel.
Local vegetation includes sage, grasses, forbs, cacti, greasewood, salt cedar, and other plants characteristic of a semi-arid upland setting environment. Vegetation is most abundant along arroyos, irrigation ditchos, in low' lying areas where water periodically ponds, and where groundwater discharges to the surface. NRC staff observed seeps, ponded water, and damp areas in natural arroyos southeast and northwest of the site.
Plant roots did not extend down into the surficial sediments in the trenches more than about ten feet.
NRC staff did not observe any seeps, damp areas, or areas of increased vegetation along the
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escarpment southwest of the disposal site.
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i The site is underlain by a thin residual soil (generally less than 1 foot),
alluvial and colluvial deposits, and Mancos Shale. The alluvial and colluvial deposits contain rounded basalt boulders up to 4 feet in maximum dimension, A sandy matrix and channel morphology are characteristic of the alluvial j
sediments, whereas the colluvial sediments are characterized by chaotic
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fabric, very poor sorting, and a clay matrix.
Discrete alluvial channels were better developed in Trench 3 than in the other.two trenches. NRC staff observed extensive gypsum mineralization in the u profile beneath the site and in the Mancos Shale,pper 8 feet of the sediment
,as exposed in the extended portion of Whiting's Ditch after its confluence with a natural arroyo north of the disposal site. The contact of the sediments with the underlying Mancos Shale is sharp, erosional, and undulatory. Across the width of the trenches, the contact elevation varied up to 3 feet. Similar variation in the elevation of the contact occurs along the long axis of the trenches.
i The Mancos Shale beneath the site consists of calcareous, montmorillonitic grey to buff colored shales and mudstones. The Shale dips gently (3 to 5 degrees) to the east.
It is fissile and well fractured in surface exposures. Shale exposures in the trenches, however, are much more competent i
and exhibit the plastic nature of the clay minerals that comprise the Mancos Shale. Exposures of the Shale weather to a characteristic grey " popcorn" surface that suggests the abundance of montmorillonite clay in the Mancos Shale.
Shallow groundwater is discharging from the alluvial and colluvial sediments above the contact with the Mancos Shale in the trenches. Groundwater fluxes into Trenches 1, 2, and 3 are about 1.3, less than 1, and 2 ';allons per minute, respectively.
Most of the seepage and damp areas occur on the' northern faces-of the trenches. Groundwater generally seeps from the trench faces at discrete locations at low points in the bedrock surface. NRC staff members tasted the i
water in Trench 3.
This water was cool and relatively soft with low concentrations of dissolved salts. The RAC is collecting, measuring, and periodically pumping water from sumps in the bottom of the trenches.
In addition, the RAC and TAC are mapping the stratigraphy observed in the trenches.
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Ms 3
Meeting:
Concurrent with the afternoon site observations, NRC staff members F11egel and Johnson met with staff of Senators Wirth and Armstrong of Colorado and representatives of BLM and Mesa County, at their request.
As a result of increased local interest and involvement in DOE's plans for remedial action of the Grand Junction tailings, the NRC staff was asked to discuss NRC's role in the UMTRA Program.
The staff explained the NRC's concurrence role as mandated by UMTRCA and described the EPA standards which govern NRC's concurrence actions.
In response to questions, the staff expressed their opinion that there probably is sufficient rock available at the Cheney Reservoir site for erosion protection.
Anticipated schedules for completion of site character-ization and subsequent preparation of reports by DOE and review by NRC were also discussed.
Meeting Attendees M. Fliegel NRC T. Johnson NRC A. Berry Sen. Tim Wirth)
J. Pepin RAC)
K. Fife Mesa County)
K. Hall fSen.BillArmstrong)
J. Dougan BLM L. Porter BLM B. Conrad BLM
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