DRC-2012-001096 - 0901a068802a9da8

State of Utah
GARY R HERBERT
Governor
GREG BELL
Lieutenant Governor
Department of
Environmental Quality
Amanda Smith
Executive Director
DRC-2012-001096
DIVISION OF RADIATION CONTROL
Rusty Lundberg
Director
TO
FROM
DATE
SUBJECT
MEMORANDUM
File
THROUGH Phil Goble Compliance Section Manager
'2-/2 Tom Rushing PG
February 2 2012
Review ofthe 1' Quarter 2011 (dated May 27 2010) 2 ' Quarter (dated August 31
2011) and 3' Quarter 2011 (dated November 30 2011) Routine Groundwater
Monitoring Reports Groundwater Discharge Permit (Permit) UG370004 Denison
Mines (USA) Corp (DUSA) White Mesa Mill Blanding Utah
This is a summary of DRC staff review of three DUSA monitonng reports for the 1' Quarter (January
March)*^ 2 Quarter (Apnl June)^"^ and 3 Quarter (July September)'-' 2011 sampling events and all
accelerated monitoring dunng those quarters as conesponds to the DUSA reports dated May 27 August
31 and November 30 2011 cited above
1 Summarv of Findings
DRC staff findings are as follows
1 The DUSA 1' Quarter 2 ' Quarter 3rd Quarter 2011 Groundwater Monitoring Reports were
received by their respective due dates June 1 September 1 and December 1 respectively
2 There was failure to implement accelerated samplmg at monitoring well MW 35 for several
single violation or OOC parameters mcluding Manganese Thallium Uranium Adjusted
Gross Alpha and Field pH
3 Time concentration plots were incorrectly plotted for Uranium at Monitonng Well MW 5
4 Turbidity values >5 NTU are still evident in several wells
5 Current QAP and field protocols for field readings at low yield wells (wells which are
pumped dry) are not consistent with the 1986 RCRA TEGD
6 THF at well MW 11 retum to baseline compliance monitonng is pending DUSA response to
a January 25 2011 DRC RFI
7 Monitoring wells in OOC (PotenUal GWCL Revisions) will be investigated per DUSA Plan
and Time Schedules currently under Executive Secretary Review
8 DUSA protocols regarding follow up when a blind duplicate analysis does not conform to the
20% RPD cntena in the QAP were not undertaken and do not appear to be appropnate
9 Discussion of the apparent violations is provided below
168 North 1950 West SaltLakeCity UT
Mailing Address PO Box 144850 SaltLakeCity UT 84114 4850
Telephone [phone] Fax [phone] TDD [phone]
www d q t h g
Pr t d 100% y I d p p
Denison Mines Groundwater Reports
1 st 2nd ^ 3rd 2011
DRC Review Memo
Page 2
2 Accelerated Monitoring and POC Wells Exceeding GWCL
When a monitonng well has a pollutant that exceeds a GWCL set forth m Table 2 of the Permit it is in
Probable Out of Comphance (POOC) status DUSA is then required to immediately initiate accelerated
sampling of that pollutant (see Permit Part IG 1) When monitonng wells have parameters that have
exceeded the Ground Water Compliance Limit (GWCL) two or more consecutive times they are in Out of
Compliance (OOC) status (see Permit Part IG 2)
In the event a consUtuent is in OOC status DUSA is required to prepare and submit within 30 calendar
days to the Executive Secretary a plan and a time schedule for assessment of the sources extent and
potential dispersion of the contamination and an evaluation of potential remedial action to restore and
mamtam groundwater quality to insure that Permit limits will not be exceeded at the compliance
monitonng point and that DMT or BAT will be reestablished m accordance with Part IG 4(c) of the
Permit
In the tables listed below are monitonng wells with parameters currently m accelerated OOC or POOC
status
Table 1 Wells Monitored Quarterly Accelerated to Monthly Monitoring
Well Class *Position Parameter Date of First
Exceedance of
GWCL
Date Accelerated
Monitormg First
Required
MW 11 Class II water D 3 Manganese
Tetrahydrofuran (THF)
Febmary 2010
February 2010
May 2010
May 2010
MW 14 Class III water D-4A Field pH February 2010 May 2010
MW 25 Class III water C 3 Field pH
Uranium
4"^ Quarter 2010
September 2010
January 2011
November 2010
MW 26^"^ Class III water C2
Field pH
Nitrate -1- Nitnte (as N)
Chloroform
Uranium
Chlonde
Dichloromethane
TDS
February 2010
Febmary 2010
February 2010
February 2010
February 2010
April 2010
September 2010
May 2010
May 2010
May 2010
May 2010
May 2010
June 2010
January 2011
MW30 Class II water D 2
Nitrate -1- Nitnte (as N)
Chlonde
Selenium
Field pH
February 2010
V Quarter 2011
Apnl 2010
2''Qtr 2011
May 2010
May 2011
July 2010
July 2011
MW 31 Class III water D 2
Nitrate -1- Nitnte (as N)
Chlonde
Sulfate
TDS
Field pH
Febmary 2010
1 'Quarter 2011
4"^ Quarter 2010
September 2010
2nd Quarter 2011
May 2010
Apnl 2011
January 2011
January 2011
July 2011
MW 35 Class II C-4B
Uranium
Manganese
Thallium
2nd Quarter 2011
2nd Quarter 2011
3'Quarter 2011
July 2011
July 2011
October 2011
Denison Mines Groundwater Reports
jst 2"''&3''*2011
DRC Review Memo
Page 3
Well Class *Position Parameter Date of First
Exceedance of
GWCL
Date Accelerated
Monitoring First
Required
Adjusted Gross Alpha 3'Quarter 2011 October 2011
D = Down gradient U = Up gradient C = Cross gradient 1 2 3 4A = Cell #
a = Monitonng well MW 26 is a pumping well for the Chloroform investigation
Wells Monitored Semi annually Accelerated to Quarterly Momtormg
Well Class *Position Parameter
Date of First
Exceedance of
GWCL
Date Accelerated
Monitoring First
Required
MW2 Class III water C 3 Adjusted Gross Alpha 4"^ Quarter 2010 1 'Quarter 2011
MW 3 Class III water D4A
Selenium
Field pH
Fluonde
2 ' Quarter 2010
2 ' Quarter 2010
2'Quarter2010
3'Quarter 2010
3' Quarter 2010
3' Quarter 2010
MW 3A Class in water D-4A
Field pH
Sulfate
TDS
2'Quarter2010
2'Quarter2010
2'Quarter2010
3 ' Quarter 2010
3'Quarter 2010
3'Quarter 2010
MW 5 Class II water D 3 Uranium 4"^ Quarter 2010 1 'Quarter 2011
MW 12 Class in water D 3 Field pH
Selenium
4^^ Quarter 2010
2 'Quarter2010
r Quarter 2011
3' Quarter 2010
MW 18 Class III water U 1
Thallium
Field pH
Sulfate
TDS
V Quarter 2010
2'Quarter2010
2 'Quarter2010
2 ' Quarter 2010
2 ' Quarter 2010
3'Quarter 2010
3'Quarter 2010
3' Quarter 2010
MW 19 Class III water U 1 Field pH 2 ' Quarter 2010 3' Quarter 2010
MW 23 Class III water D 3 Field pH 2 ' Quarter 2010 3'Quarter 2010
MW 24 Class III water D 1
Cadmium
Thallium
Field pH
2' Quarter 2010
2 ' Quarter 2010
2 ' Quarter 2010
3'Quarter 2010
3'"' Quarter 2010
3' Quarter 2010
MW 27 Class III water U 1
Nitrate -i- Nitnte (as N)
Sulfate
TDS
Chloride
Field pH
2 ' Quarter 2010
2 ' Quarter 2010
V Quarter 2010
V Quarter 2010
3'Quarter 2011
3' Quarter 2010
3'"'Quarter 2010
2"' Quarter 2010
2' Quarter 2010
4'*' Quarter 2011
MW28 Class III water D 1 Field pH
Chlonde
2 ' Quarter 2010
2 ' Quarter 2010
3' Quarter 2010
3' Quarter 2010
MW 29 Class III water D2 Field pH
Iron
4^^ Quarter 2010
2' Quarter 2011
r Quarter 2011
3'Quarter 2011
MW 32 Class III water C 2 Gross Alpha
Field pH
2' Quarter 2010
2 ' Quarter 2010
3'Quarter 2010
3'Quarter 2010
D = Down gradient U = Up gradient C = Cross gradient 1 2 3 4A = Cell #
Table 1 above is a comprehensive list of all Groundwater Monitonng Wells in Accelerated Status DUSA
IS required to notify the DRC on a quarterly basis regarding wells and parameter s which went mto
Denison Mines Groundwater Reports
jst 2"d&3''^2011
DRC Review Memo
Page 4
accelerated monitoring dunng the penod IPart I G 1(a) Accelerated Monitonng Status Reports (AMSR)]
For the three quarters of monitonng reviewed the reports have been received as follows
1 AMSR received for the 1'* Quarter Report dated May 13 2011 and received by DRC on
May 17 2011
2 AMSR received for the 2 ' Quarter Report dated August 8 2011 and received by DRC on
August 15 2011
3 AMSR received for the 3 ' Quarter Report dated November 3 2011 and received by DRC on
November 4 2011
Following IS a summary of each parameter which went into accelerated dunng each of the penods
reviewed for this memo as included in the Report (Note that DRC review of the report completeness and
agreed upon investigations and actions between DRC and DUSA regarding parameters/wells currently in
OOC status including dates of agreements and documents are detailed in number 8 below) DUSA and
the Executive Secretary will enter into a Stipulated Consent Agreement specifying conective actions for
the OOC parameters once the studies and objectives have been agreed upon
DRC will ensure that wells/parameters which have recently gone into OOC status are included in the
study plans
3 Summarv of May 13,2011,1'^ Quarter Data Results AMSR
New Accelerated Well or Start OOC Status and Parameter
Semi Annual Baseline to Quarterly Accelerated
No New Accelerated
Semi Annual Wells with Two Successive Exceedances beginning Ql (Out of Compliance)
MW 12 Field pH
MW 29 Field pH
Quarterly Baseline to Monthly Accelerated
MW 30 Chlonde
MW 31 Chlonde
Quarterly Wells with Two Successive Exceedances beginning Ql (Out of Compliance)
MW 25 Field pH
4 Summary of August 8,2011,2"' Quarter Data Results AMSR
New Accelerated Well or Start OOC Status and Parameter
Semi Annual Baseline to Quarterly Accelerated
Demson Mines Groundwater Reports
^st 2"'*& 3^^2011
DRC Review Memo
Page 5
MW 29 h-on
Semi Annual Wells with Two Successive Exceedances beginning Ql (Out of Compliance) '
MW 18 TDS
MW 29 Field pH
Quarterly Baseline to Monthly Accelerated
MW 30 Field pH
MW 31 Field pH
Quarterly Wells with Two Successive Exceedances beginning Ql (Out of Compliance)
MW 25 Field pH
MW 30 Chlonde
MW 35 Manganese
MW 35 Uranium
5 Summary of the November 3,2011,3 " Quarter Data Results AMSR
New Accelerated Well or Start OOC Status and Parameter
Semi Annual Baseline to Quarterly Accelerated
MW 27 Field pH
Semi Annual Wells with Two Successive Exceedances beginning Ql (Out of Compliance)
No New OOC
Quarterly Baseline to Monthly Accelerated
MW 35 Thallium
MW 35 Gross Alpha
Quarterly Wells with Two Successive Exceedances beginning Ql (Out of Compliance)
None
6 VIOLATION - Failure to Report or Accelerate Groundwater Momtormg at Well MW 35
Based on DRC review of the Accelerated Monthly Status Reports relevant to the review penod the
following violation was noted
Denison Mines Groundwater Reports
jst 2"''& 3'^ 2011
DRC Review Memo
Page 6
Ground Water ConcentraUon Limits (GWCL s) were set for Monitoring Well MW 35 in the Febmary 15
2011 Permit Modification The GWCL s were mcluded m the Permit and are enforceable (It is noted that
the current GWCL s at well MW 35 were calculated by multiplying the Ground Water Quality Standard
(hereafter GWQS) by a factor of 0 25 as allowed by UAC R317 6-4 5(B)(2) and are intenm pending
submission of background statistics and revision/approval of the GWCL s)
DRC noted that the GWCL s for the following Parameters were exceeded during the reviewed quarters of
data
Table 1 - Groundwater Well MW 35 Parameters Exceeding GWCL s P' 2 ' 3 ' Qtr s 2011
GWQS GWCL
Contaminant (Class II) (Class II) 1st Qtr
2011
2nd Qtr 2011 3rd Qtr 2011
Sample Date 2/15/2011 4/12/2011 8/2/2011
Manganese 800 200 248 580 267 R^'^
Thallium 2 05 <0 50 <0 50 0 52 R^*^
Uranium 30 75 12 7 19 9 18 3 R^'^
Gross Alpha 15 3 75 2 6(-i-/ 0 2) 4 4(+/ 0 5) 4 5 (+/ 0 5)
Field pH (S U ) 65 85 7 17 6 60 6 24
(1) Resampled 8/30/2011
Since MW 35 is required to be monitored quarterly accelerated monthly monitormg should have been
implemented within 30 days of receipt of the data results per Part IG 1 of the Groundwater Permit
Based on dates of lab packet receipt the affected parameters should have been accelerated as follows
Table 2 Dates that Accelerated (Monthly) Monitonng Required to be Implemented at MW 35
Parameter/ Quarter of
First GWCL
Exceedence
Date of Lab
Report
Monthly Accelerated
Monitonng Required
Starting
Date Accelerated
Monitonng
Implemented
# of Monthly
Violations
(Days)
Manganese/1^' Qtr 3/24/2011 4/2011 7/2011 3 (90 days)
Thallium/ 3" Qtr 10/4/2011 11/2011 NA
Uranium/r' Qtr 3/24/2011 4/2011 7/2011 3 (90 days)
Adjusted Gross Alpha/
3'Qtr
9/19/2011 10/2011 NA
Field pH/ 3' Qtr Field Sheet Date
8/2/2011
9/2011 None 1 (30 days)
Per DRC review of the associated AMSR s for the above violations DUSA did report the parameters
which went into out of compliance status dunng the period
Based on these findings and timelines DUSA violated Groundwater Permit No UGW370004 Part I G I
Failure to implement accelerated monthly monitonng at well MW 35 for Manganese Uranium and Field
pH
Denison Mines Groundwater Reports
jst 2°'^&3''*2011
DRC Review Memo
Page 7
Per the 2 ' Quarter 201 IReport Section 2 12 Accelerated Groundwater Monitoring DUSA did
identify the exceedences during the 1' Quarter 2011 According to DUSA It should be noted that during
Ql MW 35 was sampled on Feburary 14 2011 prior to Denison s receipt on February 18 2011 ofthe
revised GWDP containing GWCL s dated February 15 2011 At the time ofthe Ql sampling the current
GWCL s were not applicable to MW 35 Therefore sampling results from MW 35 were not addressed in
the Ql Exceedence Notice dated May 13 2011 because the GWCL s for this well were not in effect at the
time of sampling
Enforcement discretion is granted based on
1 DUSA s idenUfied and discussed their interpretation of the GWCL exceedences
2 DRC recognizes that there was confusion regarding whether the GWCL exceedences were m
force due to GWCL s being incorporated into the permit dunng the same quarter
Note Per the DUSA field sheets well MW 35 was purged on 2/14/2011 to dryness and sampled on
2/15/2011 not 2/14/2011 as stated by DUSA m the quote above
7 1^* and 2"' Qtr, 2011 Sample for Well MW 22
Monitoring Well MW 22 is not a compliance well but a general monitonng well with a semi annual
monitonng frequency DUSA has been sampling the well on a quarterly basis but has decreased the
frequency to semiannual DRC notes that DUSA monitored well MW 22 during the 2 ' Quarter in order
to keep It on the same schedule as other semiannual frequency wells
8 Discussion of Current DUSA/DRC Agreements and Plans to Evaluate OOC Parameters
DRC issued a NoUce of Violation and Order to DUSA Docket UGWl 1 02 which included a violaUon
Violation 5 for failing to submit a plan and schedule regarding OOC parameters listed m the groundwater
reports for the T 2 ' and 3 ' Quarters of 2010
Part IG 4(c) ofthe Permit for failing to provide a plan and schedule for assessment ofthe sources
extent and potential dispersion ofthe contamination and an evaluation of potential remedial action to
restore and maintain groundwater quality to insure that Permit limits will not be exceeded at the
compliance monitoring pomt and that DMT or BAT will be reestablished
Based on this violation DUSA has submitted several documents with plans to assess the source of the
listed contaminants AddiUonally the plans and time schedules address the OOC parameters included m
the 2011 reports listed in parts 3 4 and 5 above Figure 1 below depicts the generation and flow of the
submitted documents
Denison Mines Groundwater Reports
^st -2nd ^ 3rd 2011
DRC Review Memo
Pages
Figure 1 - Flow Chart of Submitted Documents Regarding Reporting and Investigation of Parameters in
OOC Status
February 1 2011 DUSA
Proposed Submittal Date
Revised GWCL s for pH Report
to be submitted end of 2 ' Qtr
2011
DRC Notice of Violation Docket No
UGWll 02 Issued May 9 2011
T
June 13 2011 Plan and Time Schedule for
violations cited m UGWll 02 violations
pertinent to Groundwater Monitoring Reports
for the 1 • 2nd 3"* and 4* quarters of 2010 the
Plan and time schedule also includes acUons
for additional GWCL exceedences in the 1 '
quarter of 2011 Groundwater Monitoring
Report
September 7 2011 Plan and Time Schedule
for violations cited m the 2 ' quarter 2011
Groundwater Monitonng Report (Note that all
previous GWCL exceedences which were not
removed from accelerated monitoring status
are carried forward from the June 13 2011
(Plan and Time Schedule)
I January 20 2011 Plan and Time Schedule
I under Utah Ground Water Discharge Permit
I UGW370004 Part 1 G 4 d-Note Based on
j DUSA/DRC Conference Calls
i Decembers 2011 and December 19 2011
February 14 2011 DRC E mail
agrees with DUSA timeline for
submittal of report
June 20 2011 DUSA Request
for Extension of the Submittal
Date for a report on Proposed
Correction or GWCL s for pH
May 13 2011 DUSA
Notice of GWCL
Exceedences for the 1'
Quarter 2011 Groundwater
Monitoring Report
Augusts 2011 DUSA
Notice of GWCL
Exeedences for the 2 '
Quarter 2011 Groundwater
Monitonng Report
Novembers 2011 DUSA
Notice of GWPL
Exceedences for the 3 '
Quarter 2011 Groundwater
Monitonng Report
Note that the most recent document to be submitted was the DUSA January 20 2011 Plan and Time
Schedule which was based on 2 telephone conversations regardmg the plan and schedule documents to
date
Based on approved actions DRC will enter into a stipulated consent agreement with DUSA including a
schedule regarding the assessment of whether the violations are due to natural background fluctuations m
which case DUSA will prepare revised staUstics and propose GWCL changes to the Executve Secretary
or if the OOC is caused by an on site source & future corrective action is needed Additional specifics
related to the current study plans and objective:^ is included in item 9 below
The transmittal letter for the review of the subject reports will include a bnef clanfication that the review
was conducted with consideration of these cunent actions
Denison Mines Groundwater Reports
^st 2"^&3''*2011
DRC Review Memo
Page 9
9 General Discussion/Summary of the DUSA Plan and Time Schedule to Address OOC
Parameters
The June 13 2011 and September 7 2011 DUSA Plan and Time Schedule Documents Categonze the
OOC parameters into 3 categones
1 Wells with OOC parameters related to decreasing pH trends
2 OOC parameters related to active groundwater pumping for remediation of the chloroform plume and
3 pH trends
DUSA Recommended Actions for Studies Related to the Decreasing pH Trends
MW 3 MW 3A MW 5 MW 11 MW 18 MW 27 MW 30 MW 31 - Pre existing Rising Trends
The June 13 2011 DUSA letter states that rising trends noted m the applicable well set (above) have been
explained as natural nsmg background in the cunent background groundwater quality report cited below
A Revised Background Groundwater Quality Report Existing Wells for Denison Mines (USA) Corp s
Mill Site San Juan County Utah October 2007 prepared by INTERA hic (INTERA 2007)
DUSA states that per the report conclusions there are increasing and decreasing trends in consUtuents in
upgradient and far downgradient and Mill site wells which provide evidence that there are natural
forces at work that are impacting groundwater quality across the entire site Denison cites this
reference to indicate a natural source for the concentration trends
Additionally DUSA cites the University of Utah Study at the White Mesa Mill
Summary of Work Completed Data Results Interpretations and Recommendations for the July 2007
Sampling Event at the Denison Mines USA White Mesa Uranium Mill Near Blanding Utah Prepared by
T Grant Hurst and D Kip Solomon Department of Geology and Geophysics University of Utah May
2008
Specifically DUSA points to the conclusions of the Study which states Stable isotope fingerprints do not
suggest contamination of groundwater by tailings cell leakage evidence that is corroborated by trace
metal concentrations similar to historically observed concentrations
For the applicable set of wells DUSA recommends a re evaluaUon of the concentration trends to
include
1 Geochemical Analysis
2 Mass Balance Analysis
3 Hydrogeologic analysis for wells distant from the Mill s tailmgs cells
The purpose of these studies would be to evaluate the behavior ofall the constituents in the well in
question to determine ifthere are any changes in the behavior of applicable constituents as compared
with the past studies
Denison Mines Groundwater Reports
jst 2"''&3''^2011
DRC Review Memo
Page 10
If significant changes are identified then DUSA would propose to the Executive Secretary further
analysis to identify the source and the extent of the contanunation
If no significant changes are identified then DUSA would propose changes to the GWCL s for the wells
and elements of concem
DUSA Recommended Study for OOC Related to Chloroform Contanunation Mitigation Groundwater
Pumping
MW 26-Pumping Well
The June 13 2011 DUSA letter proposes certain acUons for monitonng well MW 26 which is curtendy
being utilized as a pumping well for active remediation of the chloroform plume and which is in OOC
status for the following parameters
Nitrate -t- Nitnte (as N) Uranium Chloroform Chloride Field pH Dichloromethane (Methylene
Chlonde) TDS and Adjusted Gross Alpha
DUSA points out in the June 13 2011 letter that vanaUon m consUtuents (geochemical parameters) in a
pumping well is expected DUSA also states that this detemunaUon was agreed upon by the Co
ExecuUve Secretary in a September 2009 Statement of Basis DUSA proposes the following activities in
relation to the OOC status at MW 26
1 Geochemical Analysis
2 Mass Balance Analysis
The overall objective of the study will be to identify if significant changes are identified in the Source
Assessment Report that cannot be attnbuted to the pumping itself or to background influences If such
evidence is found then DUSA proposes that further study will be initiated as agreed to by the Co
Executive Secretary DUSA will also evaluate whether additional remedial actions may be appropnate
DUSA Recommended Action for Studies related to Decreasing pH Trends
MW 3 MW 3A MW 5 MW 11 MW 18 MW 30 - Decreasing pH Trends
DUSA proposes a separate line of study for groundwater monitoring wells which DUSA feels are being
impacted by decreasing trends m pH
1 Geochemical Analysis
2 Mass Balance
3 Hyrogeologic analysis for wells distant from the Mill s tailings cells
Per the DUSA June 13 2011 letter the purpose of the studies would be to
Geochemical Analysis Study to evaluate indicator constituents to determine changes m behavior for
each well since the date of the Existing Wells Background Report
r
Denison Mines Groundwater Reports
^st 2"'^&3'^2011
DRC Review Memo
Page 11
Mass Balance Analysis EvaluaUon of concentration in the groundwater in comparison with the Mill
tailings and an evaluation of any mounding at the location of the well in question
Hydrogeologic Analysis Evaluation to determine the plausibility of impact from Mill tailings
In the June 13 2011 letter DUSA refers to a letter dated Febmary 1 2011 which was submitted to
propose revision of GWCL for pH m the Groundwater Permit Per DRC review of that letter it was noted
that DUSA proposed to submit revised GWCL s for all on site wells uUhzing the pH data developed
from the Ume of initiation of the GWDP and its associated Quality Assurance Plan m 2005 to the
present Additionally the February 1 2011 letter proposed that the revised GWCL s would be generated
according to the process flow diagram m Figure 17 of the Background Study Report including box and
whisker plots statistical distnbuUon analyses and trend analyses This revision to the pH GWPL s was
based on DUSA s concem that the existing GWPL s were based on data generated at the contract
laboratory and not from field data DUSA also quotes the EPA 1986 Technical Enforcement Guidance
Document for RCRA groundwater monitonng to support the re evaluation
DRC notes that the results of that evaluation were never submitted to DRC but does note that addiUonal
correspondence occurred regarding the evaluation and that in the June 30 2011 letter DUSA states that
Denison completed this evaluation in anticipation of providing a report including revised GWCL s by
June 30 2011 a date proposed by Denison in the February 1 2011 letter Following the statistical
evaluation ofpH data by Denison s geochemical consultant INTERA Inc Denison compared the Mill s
most recent groundwater pH data from the second quarter of 2011 including accelerated sampling
results as recent as June 2011 and noted that all ofthe June 2011 groundwater results and many ofthe
other results from the second quarter were already outside the revised GWCL s to be proposed It
appears that this site wide phenomenon of decreasing pH trends may render the Logic Flow Diagram
inappropriate for setting GWCL sfor pH at the site
The DUSA June 30 2011 letter goes on to discuss the revised root cause of the pH exceedences since
It was shown that re evaluation of background values based on field pH did not resolve the issue
Denison proposed that the root cause is the dissolution of pynte in the formation mineralogy surrounding
the affected monitonng well screened intervals and states that the groundwater in contact with pyrite has
been oxygenated by surging bailing and over pumping for redevelopment ongoing pumping dunng
routine monitoring (and for some wells more frequent pumping stresses due to accelerated monitonng)
The June 30 2011 letter also states that chloroform pumping wells have been subjected to the additional
stresses of on and off pumping cycles for chloroform capture pumping Denison also states that effects of
drought regional recharge water pH and field instmmentation are being evaluated as potential
contnbutors to the pH depression phenomenon
Based on DRC Findings related to review of the Plan and Time Schedule Documents (DRC Review
Memo Dated November 14 2011) there was an agreement that the above DUSA plan of action is
appropriate however there were additional needed elements of the study that were identified by DRC
and discussed dunng a December 5 2011 Conference Call these included
1 Quantification of iron pynte concentration in core samples at the screened intervals of
affected momtormg wells to support the claim that pH trends are due to iron pynte
dissolution caused by well overpumpmg and bailing
Denison Mines Groundwater Reports
^st 2"''&3''^2011
DRC Review Memo
Page 12
2 VerificaUon that any statistical analyses will be conducted according to the approved
flow chart and/or any altemate statisUcal processes need to be submitted to DRC and
approved by the Executive Secretary
3 ElimmaUon of potential oxygenation of the aquifer by recharge from the upper wildlife
ponds should be actively eliminated by lining the ponds to avoid infiltration
4 A revised plan and time schedule will be submitted to address the discussed issues
5 A Stipulated Consent Agreement will be issued based on revision to the study plan
Based on a follow up phone conference on December 19 2011 DUSA stated that active recharge from
the upper wildlife ponds had been eliminated by shutting off the inflow valve (which delivers water from
recapture reservoir) DUSA additionally agreed that if the ponds were needed in the future (to deter
animals from using the tailmgs ponds) then the ponds would be lined
Per discussions regarding the quantification of iron pyrite in formation DUSA agreed to inspect the
existing core borings (in the White Mesa Core Bam) to determine if the analysis could be done with
existing core and/or propose additional core locations for the determination It was agreed that the
findings of such analysis would be included m a revised Plan and Time Schedule to be submitted on or
before January 20 2011
DRC received the January 20 2011 Plan and Time Schedule which is currently under review
10 THF at momtormg well MW 11
Per the DRC Review Memo for the 1' 2 ' and 3 ' Quarter 2010
''THF well MW 11 didn t have any parameters in accelerated status prior to the January 20 2010
Permit Modification THF had only been observed in well MW 11 one time before the 1' Quarter 2010
monitoring event (3 2 fig/L m 2 Quarter 2009) Since the initial exceedances of 12 fig/L all other THF
samples in well MW 11 have been below the GWCL of 11 5 jXg/L therefore well MW 11 is in POOC
status for THF
DUSA has previously argued that PVC well casing solvents and glues are the source ofthe THF detected
in monitor wells MW 1 MW 3 MW 5 and MW 12 however they have not made the same argument for
well MW 11 Ina letter dated January 12 2011 DUSA submitted a request that accelerated monitoring
for THF in well MW 11 be retumed to quarterly monitoring rather than the accelerated monthly
monitormg due to THF concentrations in well MW 11 being below 115 (ig/L in nine consecutive
sampling events since the initial exceedance of 12 {ig/L in the 1' Quarter 2010 The DRC denied this
request for thefollowing reasons 1) Due to the history of THF in groundwater at the White Mesa
Uranium Mill 2) Presence of THF recently identified in tailings wastewater 3) Historic DUSA claims on
a THF source is now suspect and 4) Groundwater hydraulic considerations at well MW 11 The DRC
documented these reasons in a January 25 2011 Request for Information (RFI) letter In the January 25
2011 RFI the DRC stated Although DUSA has previously claimed that THF is not used in its mill
operations concentrations of THF were detected above the Utah GWQS (46 [ig/L) in the Tailing Cell 4A
LDS in two consecutive samples Since Tailings Cell 4A is the current tailing cell being used by DUSA it
appears that the mill is currently using THF in its operations DUSA has not yet responded to this RFI
Denison Mines Groundwater Reports
jst -2nd ^ 3rd 2011
DRC Review Memo
Page 13
DRC notes that for the l" 2 ' and 3' Quarter 2011 monitonng THF at well MW 11 has been completed
monthly (9 monthly samples) and that the laboratory results for all months was reported below the
reporting limit (<1 0 |ig/L) Action related to retum to baseline monitonng for THF at MW 11 is pending
response to the January 25 2011 DRC RFI regarding the use of THF in the Mill operaUons
11 V\ 2°*^, and 3 Quarter Groundwater Momtormg Reports Received bv Respective Due
Dates
The DUSA 1' Quarter 2 ' Quarter 3rd Quarter 2011 Groundwater Monitoring Reports were received by
the Division of Radiation Control (DRC) by their respective due dates June 1 September 1 and
December 1 respecUvely as summanzed on the table below
Title ofthe Report Report Due Date Date DRC Received the Report
1st QTR 2011 GW Report 1 Jun 31 May 11
2nd QTR 2011 GW Report 1 Sep 31 Aug 11
3rd QTR 2011 GW Report 1 Dec 1 Dec 11
12 Analytical Laboratories Used by DUSA Certified by State of Utah to Perform Analysis for
all Analytes
The analyUcal laboratones (Energy Labs Casper and Amencan West Analytical Lab) used by DUSA to
perform analysis on the samples collected dunng the 1' 2 ' and 3^' Quarter 2011 monitoring events
were certified by the Utah Bureau of Laboratory Improvement for the parameters on which they
performed analysis
EnergyLabs Utah CertificaUon current valid through 6/30/2012 for affected parameters No 3072350515
Amencan West Analytical Utah CertificaUon current valid through 6/31/2012 for affected parameters
13 Monitoring Wells Purged for Two Casing Volumes Before Sample Collection
As stated in SecUon 6 2 7(d)(v) of the DUSA QAP two casing volumes must be evacuated from the well
before the sample is collected The DUSA QAP directs DUSA to first calculate the amount of time to
evacuate two casing volumes and then pump for that length of time After review of the 1 ' 2 ' and 3 '
Quarter 2011 reports it appears DUSA evacuated the required two casing volumes m each well pnor to
sample collecUon dunng the 1' 2 ' and 3 ' Quarter 2011 with the exception of wells which were purged
to dryness
Well MW 35 was evacuated to dryness durmg the 1' Quarter Approximately 1 well volume in 26
seconds The pump rate was 17 gpm during the 1' quarter sampling However well MW 35 was
pumped at a lower rate during the 2 ' and 3 ' quarters (Approx 0 2 GPM) allowing 2 casing volumes to be
purged pnor to sampling
Denison Mines Groundwater Reports
^st 2"''& 3™ 2011
DRC Review Memo
Page 14
DRC does not agree with the DUSA acUon of pumping the well dry dunng the 1" quarter sampling
Based on the well charactenstics a lower pumping rate should have been used for the purge and
stabilized field readings should have been venfied prior to sample collection Sampling during the 2 '
and 3' quarters at well MW 35 which followed the QAP showed collecUon of the sample during the 1'
quarter was in violation of the QAP Part 6 2 7
14 Stabilization of Indicator Field Parameters Not Reached Before Sample Collection
DRC has concems regarding purge technique when well were evacuated to dryness (low yield wells) and
only one set of field parameters were taken dunng the initial purge In these cases there was no
venfication that the field parameters were stable pnor to or dunng sampling Additionally DRC noted
that well MW 20 was purged then allowed to recharge for 5 days pnor to sampling These wells are
summarized on the table below
rd
Well No Samphng Qtr Issue
MW 35 I'Qtr 2011 Well purged dry but only one set of field parameters taken during
purging
MW 20 2'QU 2011 Well purged on 4/6/2011 field parameters taken on day of purge
Sample not collected unUl 4/11/2011 (5 days later)
MW 3A 3" Qtr 2011 Purged dry only one set of field parameters taken dunng purging
MW 12 3'Qtr 2011 Purged dry only one set of field parameters taken dunng purging
MW 24 3'Qtr 2011 Purged dry only one set of field parameters taken dunng purging
MW 37 3'QU 2011 Bailed dry only one set of field parameters taken from bucket'^
In cases where the well is purged dry due to low yield the QAP 6 2 7(d)vii requu-es that the well be
evacuated to dryness and that the number of gallons purged by recorded on the field sheet DUSA is then
required to measure and record depth to groundwater on the field sheet DRC venfied that in cases where
the monitormg well was evacuated to dryness^^the number of gallons evacuated was recorded for the 1'
2 ' and 3 ' Quarter 2011 reports Also DRC venfied that depth to groundwater was measured and
recorded (comments field) on the field sheet Therefore DUSA has complied with the cunent QAP
requirements however these activities are not consistent with low yield sampling procedures in the
United States Environmental Protection Agency September 1986 RCRA Ground Water Monitoring
Technical Enforcement Guidance Document (TEGD) as follows
According to the TEGD Part 4 2 3 Well Evacuation in the case when evacuating low yield wells
(wells that are incapable of yielding three casing volumes) the owner/operator should evacuate wells to
dryness once As soon as the well recovers sufficiently the first sample should be tested for pH
temperature and specific conductance Samples should then be collected and containenzed in the order
ofthe parameters volatilization sensitivity The well should be retested for pH temperature and specific
conductance after sampling as a measure of purging efficiency and as a check on the stability ofthe
water samples over time
DRC will request that DUSA update and submit a revised White Mesa QAP to include procedures for
field sampling low yield wells consistent with the TEGD procedures to the DRC within 30 calendar days
of receipt of an RFI letter Specifically the QAP needs to clarify that in the case where a monitonng well
has been determined to be low yield and is evacuated to dryness
Denison Mines Groundwater Reports
jst 2"d& 3rd 2011
DRC Review Memo
Page 15
a DUSA will collect the currently requu-ed field parameters (pH specific conductance
temperature) as soon as the well recovers sufficiently for sample collection (cunently defmed as
recovery to within at least 90% of the measured groundwater static surface before sampling)
pnor to collection of the sample volumes
b DUSA will then collect field parameters directly after sample collection to ensure that the
parameters show stabilization (according to the cntena currently outlined m the QAP Part 6 2 6)
15 Groundwater Samples Collected with Turbidity Measurement > 5 NTU
As stated in Section 6 2 7(d)(v) of the DUSA QAP turbidity measurement in the water should be<5
NTU prior to sampling unless the well is characterized by water that has a higher turbidity Dunng the
1' 2 ' and 3 ' Quarter 2011 monitonng events there were 20 wells where DUSA collected
groundwater samples above the 5 NTU standard (see table below)
Table 3 Groundwater Samples Collected with Turbidity Measurement > 5 NTU
Groundwater
Monitoring Event VS^ell Turbidity^^
1 Qtr 2011 MW 5''^ 162
1 Qtr 2011 MW 12*'^ 79
1 Qtr 2011 MW 20^'^ 75
1 Qtr 2011 MW 32*'^ 86
1 Qtr 2011 MW 34^'^ 111
2 " Qtr 2011 MW 1 29 4
2 "Qtr 2011 MW 5 82
2 " Qtr 2011 MW 12 87
2 " Qtr 2011 MW 22 68
2 Qtr 2011 MW 29 98
2 " Qtr 2011 MW 34 256 0
2 " Qtr 2011 MW 25 100
2 " Qtr 2011 MW 25 62
3*'Qtr 2011 MW 5 ^"^^ 100
3"' Qtr 2011 MW 11 162
3''Qtr2011 MW 23 22 1
3 Qtr 2011 MW 29 17
3 "Qtr 2011 MW 32 ^""^ 169
3 " Qtr 2011 Resample MW 32 80
3 " Qtr 2011 MW 11 41 1
Footnotes
Data for this well was obtained from Tab B of the 1 Quarter 2011 Groundwater Monitonng Report
Data for this well was obtained from Tab B of the 2 Quarter 2011 Groundwater Monitonng Report
Data for this well was obtamed from Tab C of the 2 " Quarter 2011 Groundwater Monitonng Report
Accelerated Monitonng Field Sheets
Data for this well was obtained from Tab B of the 3 " Quarter 2011 Groundwater Monitonng Report
Data for this well was obtamed from Tab C of the 3 " Quarter 2011 Groundwater Monitonng Report
Accelerated Momtonng Field Sheets
DUSA undertook a redevelopment project for groundwater monitonng wells dunng calendar years
2010/2011 in response to a DRC letter dated June 1 2010 A redevelopment report was prepared and
submitted to DRC on September 30 2011 (Received by DRC on October 3 2011) The redevelopment
report is currently under DRC review
A summary of these findings will be included in the DRC transmittal to DUSA
Denison Mines Groundwater Reports
jst 2"''&3''*2011
DRC Review Memo
Page 16
16 Relative Percentage Difference Calculations for Blind Duplicate Analysis
DRC conducted a review of the blind duplicate samples collected dunng each of the monitonng quarters
Per the facility QAP one blind duplicate must be collected with each sample batch DRC confirmed that
one blind duplicate was collected for each batch
The duplicates must be within 20% Relative Percent Difference (RPD) per the QAP Part 9 1 4 if any of
the samples do not meet this comparison cntena then DUSA must conform to the procedures for
cortective action listed in the current QAP (Per the current language in Part 10 1 a of the QAP) these
include
a Identify and define the problem
b Assign responsibility for investigating the problem
c Investigate and determme the cause of the problem
d Determine a corrective action to eliminate the problem
e Assign and accept responsibility for correcting the problem
f Implement the cortective action and evaluate its effectiveness
g Verify that the conective action has eliminated the problem
The results ofthe 3rd quarter of 2011 (MW 26/MW 65 8/30/2011) blind duplicates for Uranium did not
meet the 20% cntena (RPD value was 38 98%) DRC notes that the nonconformance was identified by
DUSA in SecUon 3 4 7 of the 3rd Quarter Monitonng Report as well as on Table G7 A in appendix G of
the report However no conecUve action was taken regarding the non conformance as required by
Section 10 1 & 10 2 ofthe QAP
Histoncally DRC has not considered an occasional deviation from the 20% RPD cntena an issue and
has not required the full cortective action as specified by the QAP It is recognized that the standard
conective acUons are not applicable to the blind duplicate analysis since it is an independent test ofthe
laboratory precision However DRC does see a need for the QAP to be updated to specify conecUve
acUons when the 20% RPD cntena is not met DRC recommends the following actions
a DUSA notification of the discrepancy to the laboratory
b DUSA request for venfication from the laboratory that no transcnption errors occurred dunng
analysis and reporting of the affected parameter
c Potential re analysis of the sample for parameters of concem if the sample is still within holding
time
DRC will request an updated QAP for the White Mesa Uranium Mill within 30 calendar days of receipt of
an RFI letter including an updated protocol for requu-ed conective acUon when blind duplicate analysis
does not meet RPD requirements
Denison Mines Groundwater Reports
jst 2"^&3'''2011
DRC Review Memo
Page 17
17 Laboratory QA/QC Flags -1^* Quarter 2011
QA/QC problems for the 1^' Quarter 2011 are summarized below
Non Conformance
Summary
Self
Identified'?
DUSA Cortective Action
Summary
DRC Findings
WellMW 11 Counting
Error > 20% Gross Alpha
Y DUSA Venfied that data
results were below the
GWCL
Gross Alpha result was
2% of the GWCL
MW 14 Counting Enor >
20% Gross Alpha
Y DUSA Venfied that data
results were below the
GWCL
Gross Alpha result was
5% ofthe GWCL
MW 30 Counting Error >
20% Gross Alpha
Y DUSA Venfied that data
results were below the
GWCL
Gross Alpha result was
5% ofthe GWCL
Matnx Spike MW 3
outside of recovery limits
for Silver
Y Recorded Discrepancy Recovery was 69%
MaUix Spike for Tin MW
11 was outside of recovery
limits
Y Recorded Discrepancy MS Recovery was 61%
Uranium Matnx Spike
recovery was not recorded
forMW 20
Y Uranium Concentration
in the Sample was 4 times
the spike level
Manganese Matnx Spike
recovery was not recorded
forMW 24
Y Manganese ConcentraUon
in the Sample was 4 umes
the spike level
Method Blank Bicarbonate
and Sulfate concentraUons
reported above the QAP
required RL
Y
• • • ^
Reported
Accelerated Monitormg
Uranium Matnx Spike
Recovery Not Recorded
Y Uranium Concentration
in the Sample was 4 Umes
the spike level
Accelerated Monitonng
Tnp Blank for 1 2
Dichlorobenzene abouve
lab range for sunogate %
recovery
Y QAP does not specify a
required range
Recovery was 121%
QAP required Repc)rting Limit The approved QAP is curtently silent on how field blanks results should
have a beanng on groundwater sample mterpretaUon
Note DRC reviewed the holding time summary chart no exceedences of holding times were noted
Denison Mines Groundwater Reports
^st 2"''&3''^2011
DRC Review Memo
Page 18
18 Laboratory QA/QC Flags 2°" Quarter of 2011
QA/QC problems for the 2 ' Quarter 2011 are summarized below
Non Conformance
Summary
Self
Identified'?
DUSA CorrecUve Action
Summary
DRC Fmdings
Routine Reporting Limit
Check found discrepancy
regarding some parameters
which were raised due to
dilution of the sample
(sample matnx
interference)
Y Discrepancies were
reported
Raising RL s due to
sample matrix is
common It may be
appropnate to raise the
RL s in the facility
QAP
MW 1 MW 2 MW 3
MW 3A MW 5 MW 11
MW 12 MW 14 MW 15
MW 17 MW 18 MW 19
MW 20 MW 23 MW 24
MW 25 MW 28 MW 30
MW 34 Counting Errors
for Adjusted Gross Alpha
were >20%
Y DUSA Venfied that data
results were below the
GWCL
DRC venfied that all
affected results were
approx 2 5 % of the
GWCL Also noted
that higher
concentration results
for Adjusted Gross
Alpha in other wells
showed much lower
counting ertors
Low Matrix Spike
Recoveries for Silver Tin
and Chloromethane
Y Recorded the
Discrepancy
No requirements in
curtent approved QAP
High Matrix Spike
Recovery for Chloroform
Y Recorded the
Discrepancy
No requirements in
curtent approved QAP
Matrix Spike Recovery not
Calculated for Uranium
and Vanadium
Y Uranium Concentration
in the Sample was 4 Umes
the spike level
High Surtogate Recovery
for 1 2 Dichlorobenzene
p Bromofluorobenzene
and Toluene
Y Recorded the
Discrepancy
No requirements m
curtent approved QAP
Method Blank Bicarbonate
concentrations reported
above the QAP required
RL
Y Recorded
Accelerated Monitonng
Uranium and Manganese
Matrix Spike Recovery
Not Recorded
Y Uranium and Manganese
Concentrations in the
Sample was 4 times the
spike level
High Matrix Spike
Recovery for Selenium
Y Recorded the
Discrepancy
No requirements in
curtent approved QAP
Note DRC reviewed the holding time summary chart no exceedences of holding times were noted
Denison Mines Groundwater Reports
jst 2"'* & 3''* 2011
DRC Review Memo
Page 19
19 QA/QC Sample Data Problems - 3 ^ Quarter of 2011
QA/QC problems for the 3' Quarter 201 are summarized below
Non Conformance
Summary
Self
Identified'?
DUSA Conective Action
Summary
DRC Findings
Routine Reporting Lirmt
Check found discrepancy
regarding some parameters
which were raised due to
dilution of the sample
(sample matrix
interference)
Y Discrepancies were
reported
Raising RL s due to
sample matnx is
common It may be
appropriate to raise the
RL s in the facility
QAP
MW 11 MW 14 MW25
MW 27 MW 30 MW 31
MW 36 Counting Enors
for Adjusted Gross Alpha
were >20%
Y DUSA Venfied that data
results were below the
GWCL
DRC venfied that all
affected results were
approx 2 5 % of the
GWCL
Low Matnx Spike
Recovenes for Silver
Adjusted Gross Alpha and
Napthalene
Y Recorded the
Discrepancy
No requirements in
current approved QAP
Matnx Spike Recovery not
Calculated for Manganese
Y Uranium Concentration
in the Sample was 4 Umes
the spike level
High Surrogate Recovery
for p Bromofluorobenzene
Y Recorded the
Discrepancy
No requirements in
current approved QAP
High Matrix Spike
Recovery for Manganese
Y Recorded the
Discrepancy
No requirements in
current approved QAP
Note DRC reviewed the holding time summary chart no exceedences of holding times were noted
20 Review of Time Concentration Plots
The Permit Part IF 1 g requires DUSA to submit Time Concentration Plots for each monitonng well for
chlonde fluoride sulfate and uranium
The Uranium Time Concentration Plot for monitonng well MW 5 included in the 3' Quarter 2011 is
incortect (does not match the 2011 reported laboratory results)
Failure to provide a curtent updated Time Concentration Plot for Uranium at monitoring well MW 5 is a
violation of Part IF 1 g of the groundwater permit
NOED Justification
It IS recommended that the Executive Secretary grant enforcement discretion based on
Denison Mines Groundwater Reports
jst 2"'*&3'''2011
DRC Review Memo
Page 20
1 Uranium monitoring at well MW 5 was accelerated from Semi Annually to Quarterly starting the
1'' Quarter 2011 (IniUal exceedence was dunng thel'' Quarter 2010) Additionally well MW 5
was included in the DUSA June 13 2011 Plan and Time Schedule under Utah Groundwater
Discharge Permit UGW370004 Part I G 4(d) white Mesa Mill Specifically well MW 5 is
included m a category with wells which have conUnued rising trend and will be evaluated to
insure that the continued trend is consistent with previous analysis Thus the nsmg trend has
been documented in other reports and evaluation has been initiated
2 This IS the first noted violaUon regarding the Groundwater Time ConcentraUon Plots Future
violations will be subject to formal enforcement
21 Violations Where a Notice of Enforcement Discretion is Recommended
1 MW 35 Failure to Accelerate - Per Item Number 6 Above
2 Time Concentration Plot for U at MW 5 - Per Item Number 20 Above
22 Requests for Information
1 Procedures regarding field parameter stabilization for wells pumped dry - Per Item Number 14
Above
2 Response to DRC letter regarding THF Per Item Number 9 Above
3 Advisory regarding non conformance for blind duplicate MW 26/MW 65 8/30/2011 - Per Item
Number 16 Above
23 Advisories
1 Redevelopment Plan curtently under review Turbidity Findings - Per Item Number 15 Above
References
^ Denison Mines (USA) Corp May 27 2011 1' Quarter 2011 Groimdwater Monitonng Report
Groundwater Discharge Permit UGW370004 White Mesa Uranium Mill
^ Denison Mines (USA) Corp August 31 2011 2Quarter 2011 Groundwater Monitonng Report
Groundwater Discharge Permit UGW370004 White Mesa Uranium Mill
^ Denison Mines (USA) Corp November 30 2011 3^^ Quarter 2011 Groundwater Monitoring Report
Groundwater Discharge Permit UGW370004 White Mesa Uranium Mill
"^Denison Mines (USA) Corp March 22 2010 White Mesa Uranium Mill Ground Water Monitoring
Quality Assurance Plan (QAP) Revision 6
Hydro Geo Chem Inc September 30 2011 Redevelopment of Existing Perched Monitoring Wells
White Mesa Uranium Mill Blanding Utah