SECTION IV -- The Dirt Cover Remedy

SECTION IV -- THE DIRT COVER REMEDY IMPLEMENTED BY SANDIA NATIONAL LABORATORIES AND APPROVED BY THE NEW MEXICO ENVIRONMENT DEPARTMENT IS INADEQUATE TO PROTECT THE ENVIRONMENT AND DOES NOT MEET REGULATORY REQUIREMENTS

 

  1. The description of the Sandia MWL as a "landfill" in reports by DOE/Sandia and NMED is incorrect and misleading. A landfill is an engineered facility that has liners, leachate detection and leachate removal capabilities. 40 CFR 264.301. The MWL has none of these engineered features. In fact, the Sandia MWL dump was named the "TA-3 low-level radioactive waste dump" during the 30 years of waste burial operations from March 1959 through December 1988.

    An example of the mischaracterization of the MWL functions as a landfill in testimony by DOE staff person, Mr. John Gould, at the NMED December 2004 Public Hearing. Mr. Gould stated: "Landfills have a purpose. The purpose of landfills is to contain waste and isolate it to prevent impacts on human health and the environment (Transcript, v. I, p. 34, l.17, 18 & 19).

    The historical record shows that the design and operation of the Sandia "mixed waste landfill" is as a dump with the wastes haphazardly buried in unlined pits and trenches. Wastes were often not inventoried and were randomly cast into the dump in paper cartons, plastic bags and wooden crates.  DOE/Sandia and the NMED have not recognized that the monitoring well data show the release of wastes buried in the MWL dump have contaminated the groundwater. Cadmium, chromium, nickel and nitrate were found. In addition, the DOE/Sandia computer modeling studies in 1995 and 2007 identified that the wastes released from the MWL dump may have contaminated the groundwater with the highly toxic solvent tetrachloroethene (PCE).

  2. The wastes in the MWL dump were not adequately characterized. For example, Comment Responses to USEPA Notice of Deficiency (November 1994) stated:

Comment 6 Response: "Hazardous constituents which may have been disposed of at the MWL include lead shielding, barium, beryllium, and chromium, as well as organic wastes containing TCE, carbon tetrachloride, organic acids, and toluene-based scintillation cocktails.

"The actual concentrations and quantities of hazardous wastes disposed of at the MWL are unknown, and may never be known. Unfortunately, many of the records on the wastes disposed of at the landfill have been purged, and the existing records contain limited information on the quantities, concentrations, and location(s) of hazardous constituents disposed of at the MWL." (Administrative Record AR 06511). 

  1. There is great uncertainty in the amount and type of wastes buried in the Sandia MWL dump. At the MWL dump, a large and poorly documented inventory of commingled hazardous wastes, low-level radioactive wastes, and mixed wastes (i.e., radioactive wastes with a component of hazardous wastes) were carelessly buried in unlined trenches and pits. (See Figures 3, 4 and 5). The contradictory information on the total quantity of wastes buried in the MWL dump ranges from 100,000 cubic feet to greater than 780,000 cubic feet and up to 1,500,000 cubic feet. The NMED April 29, 2004 Compliance Order on Consent (Consent Order) lists the hazardous wastes buried in the MWL dump to "include acids, metals, organic solvents and other organic compounds" (p. 43). The solvents include in part cancer and disease causing tetrachloroethene (PCE), trichloroethene (TCE) and dichlorodifluoromethane (CFC-12). The metals include in part beryllium, cadmium, chromium, nickel and lead.

     

    The DOE/Sandia 2007 fate and transport computer model (FTM) Report 2 lists the radioactive wastes buried in the MWL dump to include in part amercium-241, cesium-137, cobalt-60, plutonium-238, plutonium-239, radium-226, radon-222, strontium-90, thorium-232, tritium and uranium-238 (p.3).

  2. The poorly managed disposal and maintenance practices at the Sandia MWL dump allowed a large amount of water to enter the buried wastes. In 1967, 271,000 gallons of reactor coolant water was disposed in Trench D. FOIA documents reveal a DU fire occurred at the MWL in 1974. The precipitation and uncontrolled surface water flows onto the MWL dump introduced a large and unknown amount of water into the buried wastes increasing the likelihood of contaminant transport to the groundwater. There was poor control of precipitation and surface water run-in to the wastes dumped into the unlined trenches and pits 1). during the 30 years of disposal operations from March 1959 through December 1988 and 2). during the 18 years from 1989 to 2006.

     

    The annual amount of precipitation that fell on the MWL dump was 8.5 inches. The poor control of water entering the buried wastes at the MWL dump is illustrated by a memorandum dated November 20, 1996 from Sandia staff person Mr. Jerry Peace to DOE staff person Mr. John Gould. The pertinent excerpt from the memo follows:

    "Pit caps in the classified area [of the MWL dump] are in serious need of repair. Many concrete caps have collapsed under their own weight because they were not formed, reinforced, or finished when poured. Plywood caps need immediate attention because they are rotting and slumping into the pits. These collapsed pit caps act as funnels, channeling precipitation into buried waste [Emphasis supplied]. These caps have collapsed because backfilled soils have settled over time, leaving a void directly beneath the concrete or plywood cap."

    In 2006, berms were installed around the perimeter of the Sandia MWL dump to prevent surface water from rain storms from flowing on to the MWL dump during the installation of the subgrade layer of compacted dirt over the surface of the MWL dump. Citizen Action used the Freedom of Information Act (FOIA) process to obtain Stormwater Pollution Prevention Plan Inspection and Maintenance Report Forms that document the berms installed around the MWL dump were breached on August 16, 2006 by a rain storm. The Stormwater Form dated August 16, 2006 stated :

    Major rain event exceeded design criteria [for the berms]. Berms breached on east and west side. Three breaches on west side [of MWL dump]. Minor breaches on east side. Little ponding remains.

    The surface water flows from rain storms breached the berms and flowed onto the MWL dump. The large volume of surface water that flowed onto the MWL dump in 2006 during the construction of the subgrade layer shows that large volumes of surface water were allowed to flow onto the MWL dump for 50 years from 1959 to 2006.

  3. The NMED decision in 2005 to leave the commingled hazardous, mixed and radioactive wastes in place below a dirt cover was based on unreliable data from defective groundwater monitoring wells. The data came from a network of groundwater monitoring wells that were described by government scientists as being in the wrong locations, insufficient in number and not in compliance with RCRA.

 

The minimum requirement in RCRA is for a network of three downgradient contaminant detection monitoring wells and one upgradient background water quality monitoring well. The first four monitoring wells installed in 1988 and 1989 at the Sandia MWL dump (i.e., wells MWL-MW1, -MW2, -MW3 and -BW1) were installed at the wrong locations.  See here -- replace BW1 to the east and more directly upgradient of the MWL, consistent with normal practice for installation of background wells. The incorrect assumption had been made that the direction of groundwater flow at the water table below the MWL dump was to the northwest. (See Figure 8). (See here -- recognizing that groundwater flows west-southwest). The reports below show that it was conclusively recognized beginning in 1991 that the direction of groundwater flow below and downgradient from the MWL dump was to the south or southwest. This meant that monitoring well MWL- MW3 was the only downgradient monitoring well and that no upgradient background monitoring well existed. But the only downgradient well MWL-MW3 did not produce reliable and representative water samples for other factors. 

Nevertheless, DOE/Sandia continued to offer data and NMED continued to accept data from the improperly positioned wells for decision making up to the present.

The reports describing the defective groundwater monitoring wells were issued during the period from 1991 to 1998 by scientists from the DOE Tiger Team, Los Alamos National Laboratory, NMED and the U.S. Environmental Protection Agency (EPA). Four of the reports that described the requirement to replace all of the seven monitoring wells installed at the MWL dump over the period 1988 to 2007 are summarized here:

    • The Los Alamos National Laboratory (LANL) wrote a report in 1991 (Rea, 1991) that described the southwest direction of the groundwater flow and the failure of the monitoring well network at the Sandia MWL dump to be in compliance with RCRA. The LANL report stated:

       

       

      "It is stated that "three additional wells were installed, two downgradient and one upgradient…" It would be appropriate to mention here that the data from these [four] wells indicated that the network has in fact only one downgradient well [i.e., well MWL-MW3] and no wells that are definitely upgradient."

      The data from the present monitoring well network indicates that there is only one downgradient and no upgradient wells. This in itself establishes the inadequacy (under RCRA) of the present well network.

    • A 1993 NMED report by NMED staff Mr. Will Moats and Ms. Lee Winn (Moats and Winn, 1993) describes the fact that the direction of groundwater flow at the water table below the MWL dump was to the south or southwest rather than the northwest. This made the monitoring well network "inadequate" as follows:

      The hydrogeologic conditions at the MWL have not been adequately characterized. . . Water level data from July 1992 indicate south-directed or southwest directed flow. However, the gradient and direction of ground-water flow are not known with reasonable certainty (p. 3).

      The detection monitoring system that currently exists at the MWL is inadequate because the direction and speed of ground-water flow can not be determined with reasonable certainty (p.7). The 2008 DOE/Sandia Report continued the mistake that the direction of groundwater flow at the water table below the MWL dump is to the northwest even after the NMED HWB issued a letter on July 2, 2007 that the direction of groundwater flow was to the southwest.

    • The Environmental Protection Agency (EPA) Region 6 issued a Notice of Deficiency (NOD) Report on September 22, 1994 (EPA, 1994) for the March 1993 DOE/Sandia Phase 2 RCRA Facility Investigation (RFI) Work Plan for the Sandia MWL dump. Despite the EPA 1994 NOD Report, DOE/Sandia described the defective and unreliable monitoring well network at the Sandia MWL dump as a reliable network of monitoring wells in the 1996 Phase 2 RCRA Facility Investigation (RFI) Report. The 1994 EPA Region 6 NOD Report rejected the DOE/Sandia description of a reliable network of monitoring wells in the following pertinent excerpt:

      Comment no. 11. On page 2-31 [in the RFI Work Plan], the third paragraph states that regional potentiometric maps indicate that the hydraulic gradient at the MWL is toward the west and northwest. As shown in Figure 2-21, the MWL monitoring well network (i.e., MWL-BW1, MWL-MW1, MWL-MW2, and MWL-MW3) has been installed based on the assumed regional hydraulic gradient. However, the third paragraph further continues to state water level data collected from the MWL monitoring wells suggests the hydraulic gradient is to the southwest (p.5).

      Based on the southwest gradient flow of groundwater, the MWL monitoring wells are located cross gradient instead of downgradient from the MWL; therefore, contaminants emanating from the MWL may not be detected in the monitoring wells.

      The EPA 1994 NOD Report presented findings that the monitoring well network installed at the MWL dump was not reliable to detect groundwater contamination from the wastes buried in the dump. However, the network of monitoring wells was not improved at any time from the network identified as unreliable in the EPA 1994 NOD Report and in the earlier reports by LANL (REA, 1991) and the NMED HWB (Moats and Winn, 1993).

      • 1988 – well MWL-MW1 / The defective monitoring well was plugged and abandoned in 2008.

      • 1989 – wells MWL-MW2, -MW3 and -BW1 / The three defective monitoring wells were plugged and abandoned in 2008.

      • 1993 – well MWL-MW4 / The defective monitoring well is in the current network.

      • 2000 – wells MWL-MW5 and -MW6 / The two defective monitoring wells are in the current network.

      • 2008 – wells MWL-MW7, -MW8 and -MW9 / The three defective monitoring wells are in the current network.

      • 2008 – well MWL-BW2 / The new background water quality well may be defective because the drilling and well construction requirements in 

 

In 1998 the NMED HWB issued a Notice of Deficiency (NOD) Report for the 1996 DOE/Sandia Phase 2 RCRA Facility Investigation (RFI) Report. The NMED 1998 NOD Report described the overall failure of DOE/Sandia to install a reliable network of monitoring wells at the Sandia MWL dump. The NMED 1998 NOD Report (Garcia, 1998) identified the following five deficiencies with the 1996 Phase 2 RCRA Facility Investigation (RFI) Report for groundwater protection at the MWL dump:

#1 deficiency. Well MWL-MW3 was the only downgradient monitoring well. The pertinent excerpt from the 1998 NMED NOD Report follows:

The water-table map indicated that there is only one downgradient monitor well at the Mixed Waste Landfill [i.e., well MWL-MW3]. Normally, a minimum of three downgradient wells is required for an adequate detection monitoring system.

The 1998 NMED NOD Report required DOE/Sandia to install two new monitoring wells west of the MWL dump with the well screens installed across the water table in the fine-grained alluvial fan sediments. Accordingly, wells MWL-MW5 and -MW6 were installed west of the MWL dump in 2000. However, the geologic cross-section in Figure 6 shows that the screens in the two monitoring wells were installed too deep for the intended purpose to monitor at the water table in the fine-grained alluvial fan sediments.

The NMED Hazardous Waste Bureau (HWB) has not, but should require replacement of the unreliable monitoring wells as is required by the April 29, 2004 Consent Order (p.63) for monitoring wells that do not serve their intended purpose. Figure 7 shows that the two unreliable monitoring wells MWL-MW5 and -MW6 are in the current network of monitoring wells. In addition, DOE/Sandia proposes to use the two unreliable monitoring wells that do not allow accurate assessment of groundwater contamination in the long-term monitoring and maintenance plan for the MWL dump (DOE/Sandia, 2007).

#2 deficiency. The upper screen in the onsite monitoring well MWL-MW4 was installed too deep below the water table for the well to measure the elevation of the water table or detect groundwater contamination at the water table. The pertinent excerpts from the 1998 NMED NOD Report follow:

The top of the upper screen of MWL-MW4 is located approximately 22 ft below the water table. Because of the vertical gradient and the way the well is constructed, MWL-MW4 is of no value for determining the elevation of the water table (and therefore, the horizontal direction of ground-water flow and the horizontal gradient.

Also, because the top of the upper screen of MWL-MW4 is located 22 ft. below the water table, the well is of little value for detecting any groundwater contamination (if any exists) that may be present in the saturated zone just below the water table.

The installation of the upper screen in well MWL-MW4 too deep below the water table is displayed on Figure 6. The NMED has not, but should require replacement of the defective monitoring well. Many DOE/Sandia reports present the unreliable water quality data collected from the defective well MWL-MW4 for the incorrect conclusion that the MWL dump has not contaminated the groundwater below the Sandia MWL dump.

#3 deficiency. The NMED 1998 NOD Report required DOE/Sandia to prove on a technical basis that the high nickel concentrations measured in the groundwater samples collected from monitoring wells MWL-MW1 and -MW3 were only from the corrosion of the stainless steel well screens as follows:

"DOE/SNL must support their position on a technical basis that the elevated nickel levels detected in groundwater samples from monitor well MWL-MW1 (and MWL-MW3) are a result of the corrosion of 304 stainless steel well screen; otherwise, such elevated levels of nickel will be attributed to a release of contaminants from the landfill."

DOE/Sandia did not prove that the high nickel concentrations in the groundwater samples collected from monitoring wells MWL-MW1 and -MW3 were not from the nickel wastes buried in the MWL dump. DOE/Sandia continued the incorrect assumption and unproven conclusion that the high concentrations of dissolved nickel were only from corrosion of the stainless steel well screens.

The nickel concentrations measured in the groundwater samples collected from the four monitoring wells at the MWL dump that had stainless steel screens are listed in Table ES-2 that can be found at p. 29 of Citizen Action's Executive Summary. The nickel data in Table ES-2 show the remarkably high dissolved nickel concentrations measured in the groundwater samples collected from the contaminant detection monitoring wells MWL-MW1 and -MW3 located close to the MWL dump compared to the low dissolved nickel concentrations measured in the groundwater samples collected from the two background monitoring wells MWL-BW1 and -MW2 located distant from the MWL dump.

The high dissolved nickel concentrations measured in the groundwater samples collected from monitoring wells MWL-MW1 and -MW3 are statistically significant evidence under RCRA criteria of groundwater contamination from the nickel wastes buried in the unlined pits and trenches at the Sandia MWL dump.

Table ES-2 shows the high dissolved nickel concentrations measured in the first groundwater samples collected from monitoring well MWL-MW1 in the early 1990s before the assumed onset of corrosion in the stainless steel well screens beginning in 1992 (Pruett, 2005). RCRA requires replacement of monitoring wells with corroded screens that prevent reliable detection of contamination.

The NMED HWB continued acceptance of the unreliable data that were not in compliance with RCRA and the NMED Consent Order up to the DOE/Sandia Report issued in 2008. The NMED HWB did not require replacement of the unreliable monitoring wells MWL-MW1 and -MW3 until a letter issued by NMED HWB Chief James Bearzi on July 2, 2007 as follows: Additionally, both wells are also constructed with stainless steel screens, which are suffering corrosion to such a degree that the wells can no longer produce water samples that are representative of aquifer conditions for chromium, iron, and nickel.

In fact, the NMED knew in 1992 that the two corroded monitoring wells MWL-MW1 and -MW3 did not produce reliable and representative groundwater samples for detection of chromium, nickel, other RCRA metals and many radionuclides including americium and plutonium.

      <p">Nevertheless, NMED relied on 12 years of data from the unreliable monitoring wells to recommend leaving the MWL dump wastes buried below a dirt cover. This is shown by Finding of Fact 81 in the Hearing Officer's Report (Pruett, 2005) as follows:
81. Elevated levels of nickel and chromium have been detected since 1992 in MWL-MW1, MWL-MW2, MWL-MW3 and MWL-BW1, which wells are all constructed with stainless steel well screens. NMED attributes these elevated levels to corrosion of the stainless steel well screens.

There are four issues in Finding of Fact 81:

    • First, DOE/Sandia did not provide a technical basis for the incorrect assumption that the elevated levels of nickel measured in groundwater samples collected from wells MWL-MW1 and -MW3 were only from corrosion. Therefore, the NMED 1998 NOD Report attributed the elevated levels of nickel in the water samples collected from the two wells to groundwater contamination from the wastes buried in the MWL dump.

    • Second, the very low median dissolved nickel concentration of 1.2 ug/L measured in the groundwater samples collected from the new background monitoring well MWL-BW2 DOE/Sandia, 2009, 2010) satisfy RRA criteria that the high dissolved nickel concentrations measured beginning in the early 1990s from monitoring wells MWL-MW1 and -MW3 are evidence of nickel groundwater contamination from the wastes buried in the MWL dump.

    • Third, beginning with the first water samples collected in 1990, RCRA criteria identified that the elevated levels of cadmium, chromium, nickel and nitrate in the water samples collected from wells MWL-MW1 and -MW3 compared to the low or not detected concentrations in the background monitoring well MWL-BW1 as evidence of groundwater contamination from the wastes buried in the MWL dump. DOE/Sandia and the NMED HWB claim that the septic systems in TA-3 are the source of the high nitrate concentrations that are present in the groundwater at the water table below the MWL dump. The distant TA-3 septic systems can not be the source of the nitrate contamination unless the lateral speed of groundwater travel in the fine-grained alluvial fan sediments is several orders of magnitude greater than 0.17 feet/year.

    •  

      Fourth, The corroded well screens prevented the four monitoring wells from producing reliable and representative groundwater samples. RCRA and the NMED Sandia Consent Order require replacement of monitoring wells that do not produce reliable and representative water samples. The above Finding of Fact 81 in the Hearing Officer's Report is evidence that RCRA required replacement of the defective monitoring wells MWL-MW1 and -MW3 in 1992. However, the two unreliable monitoring wells were not replaced until 2008 (The replacement wells are also unreliable – see Section Executive Summary- p.15, #4 deficiency..

The NMED 1998 NOD Report recognized that the data collected from pumping tests were unreliable and not usable to calculate the speed of groundwater travel below the MWL dump as follows:

The pumping tests for monitor wells MWL-MW1, MWL-MW2, MWL-MW3, and MWL-MW4 appear to have failed because the yield of each well was too small to permit a successful pumping test to be conducted. The pumping test conducted on MWL-MW4 (Lower) also appears to have failed, . . . none of the drawdown curves appears to have a form which matches that of a type curve. Therefore, the reported values for hydraulic conductivity and transmissivity are not considered by the HRMB [now the NMED HWB] to be reliable [Emphasis added](p. 7-8).

In addition, the NMED 1993 Report (Moats and Winn, 1993) recognized that the three mud- rotary monitoring wells MWL-MW2, -MW3 and -BW1 did not produce reliable data on hydraulic properties as follows:

The use of mud-rotary drilling methods should be avoided in any future monitor well installations at the MWL. Mud rotary is not a preferred drilling technology due to its potential detrimental impacts to ground-water quality and the hydraulic characteristics of an aquifer (p. 3). Nevertheless, DOE/Sandia used the unreliable pumping test data that was rejected by the NMED 1998 NOD report and the unreliable hydraulic properties measured in the three mud-rotary wells (Moats and Winn, 1993) to calculate incorrect values for the speed of groundwater travel below and away from the MWL dump (Goering et al., 2002).

#5 deficiency. The NMED 1998 NOD Report required a risk assessment of the potential impacts of the Sandia MWL dump on local and regional groundwater quality as follows:

The nature and extent of subsurface contamination indicate that some contaminants are a potential threat to ground-water quality beneath and downgradient (west) of the MWL. A simple screening comparison of contaminant concentrations in subsurface soils against available EPA soil screening levels (SSL's) developed for the protection of ground-water resources demonstrates exceedences for cadmium and nickel (U. S. EPA, 1996, Soil Screening Guidance: Technical Background Document, EPA/540/R-95/128. Office of Emergency and Remedial Response, Washington, DC. PB96-963502) (p.4).

Therefore, the risk assessment for the MWL must evaluate potential impacts of cadmium, nickel, and other contaminants (metals such as cobalt and copper, and radioactive materials such as uranium and tritium, for which SSL's are not available at this time) on local and regional ground-water quality (p.4-5).

The risk assessment required by the NMED 1998 NOD Report was not performed. The risk assessment is a requirement under RCRA because the MWL dump has contaminated the groundwater. The nature and extent of the groundwater contamination is not known because a reliable network of monitoring wells was not installed at any time.

There are two different zones of saturation beneath the MWL dump, the fine-grained alluvial fan sediments and the deeper highly productive Ancient Rio Grande (ARG) sediments. The risk assessment should be performed after the required networks of monitoring wells are installed in the two zones of saturation beneath the MWL dump and sufficient water

quality data are collected from the two networks. None of the deficiencies in the NMED 1998 NOD Report (or in the EPA 1994 NOD Report) were resolved to the present time in 2011. 

The NMED HWB did not require DOE/Sandia to replace the two defective monitoring wells MWL-MW5 and -MW6. Instead, the NMED HWB accepted the water quality data from the two defective monitoring wells as reliable and representative over all time to the present in 2011. These two defective wells are still in the current network and proposed for long term monitoring wells.

The U. S. Congress commissioned a study of contamination issues at the Sandia MWL Dump by WERC. WERC (A Consortium for Environmental Education and Technology Development at the New Mexico State University) performed two expert reviews of contamination issues at the Sandia MWL dump (WERC, 2001, 2003). DOE/Sandia staff knowingly presented false information to two expert peer review panels performed by WERC in 2001 and 2003. The false information presented was that there was a reliable network of monitoring wells at the Sandia MWL, that BW-1 was an upgradient monitoring well, that that MW1, MW 2, MW5 and MW6 were down gradient wells and a large number of water samples collected from the wells over a period of ten years showed that the MWL had not contaminated the groundwater. DOE/Sandia did not address that onsite monitoring well MW4 was screened too deep below the water table.

The information contained in the six reports showing that there was only one downgradient well and no background monitoring well was omitted from the DOE/Sandia presentation to WERC. The presentation of the Groundwater Monitoring Program Overview by on March 22, 2001 included in the final WERC Report as reference #108 presented background well BW-1 as Upgradient and MW1, MW2, MW3, MW5, MW6 as Downgradient. In fact, DOE/Sandia did not provide any of the six reports written over the years 1991 to 1998 that described the monitoring well network as inadequate to detect groundwater contamination from the MWL dump. 

The WERC did not consider data quality but only assumed that DOE/Sandia was presenting accurate information.

The statement in the WERC report that monitoring wells were installed in the "underlying aquifer" is incorrect. A monitoring well network was not installed in the underlying aquifer in the highly productive ARG Deposits. Installation of a network of monitoring wells in the productive ARG Deposits is a requirement of RCRA and the NMED Sandia Consent Order.

The NMED Administrative Record (AR) shows that at the time of the public hearing, NMED omitted from testimony that there was not a RCRA compliant and reliable well monitoring network at the MWL. Testimony at the Public Hearing in December 2004 was that groundwater flow was to the west-northwest. (Hearing Officer "HO" Findings, #41, p.8). However, NMED knew from 1993 to the present that groundwater flow was to the south- southwest. Therefore, at the public hearing NMED knew the monitoring wells were not in the required upgradient and downgradient locations from the reports issued during the period from 1991 to 1998 by scientists from the DOE Tiger Team, Los Alamos National Laboratory, NMED and the U.S. Environmental Protection Agency (EPA).

NMED incorrectly asserted at the 2004 public hearing that there was "No contamination of the groundwater" even though NMED knew there were no reliable groundwater monitoring wells at the Sandia MWL at any time. (Hearing Officer HO #69, p.13 - HO #77 & #79, p.14). "[T]he landfill presents little risk of groundwater contamination…" (HO #73, p.13) However, NMED knew risk could not be evaluated because the monitoring network was not adequate.

At the 2004 public hearing, NMED knew the MWL monitoring wells were at wrong locations, well screens were misplaced, wells were constructed and sampled incorrectly and that corroded well screens existed.

At the 2004 public hearing, NMED knew the monitoring well data were inadequate to select the dirt cover as a remedy based on the data from a defective monitoring well network. In fact, the NMED 2007 Fact Sheet for LANL MDA H shows that NMED knows that a soil cover will not be protective of a) surface pathways for contamination or b) for groundwater protection. The NMED contaminants of concern at both MDA H and the MWL are tritium and solvents (VOCs). Excerpts from the NMED Fact Sheet for MDA H are pasted below: 

"However, NMED's assessment indicates that the ET cover can only partially prevent intrusion of deep-rooting plants and burrowing animals. In addition, this alternative does not address the current and future releases of VOCs and tritium to the subsurface at MDA H [emphasis supplied]. -- NMED questions the long- term reliability of the engineered ET cover in preventing the intrusion of deep- rooting plants and burrowing animals. -- The potential for biointrusion to the shafts from the surrounding areas poses not only the risk of transport of waste to the surface, but also the risk of creation of conduits that could channel water through the [unlined disposal] shafts." (p. 11, NMED Fact sheet for MDA H)

Additionally, NMED was informed by the 2006 TechLaw, Inc. report that the dirt cover for the MWL dump would not maintain its integrity for the 1000 year period required. 

The NMED Final Order (Curry 2005) required that a Fate and Transport Model be made to model contaminant movement beneath the dump. During discussions between Citizen Action and Southwest Research and Information Center (SRIC) and the NMED about the Fate and Transport Model, NMED withheld a 2006 TechLaw, Inc. report from the public by NMED until late 2009. When Citizen Action requested the TechLaw report in 2006, NMED sued Citizen Action to prevent the release of the TechLaw report that cast further doubt on the NMED decision for the dirt cover remedy.  The TechLaw Report identified issues with:

  • 1). the incorrect design of the dirt cover,

  • 2). the poor long term viability of the dirt cover, and

  • 3). the deficiencies in the DOE/Sandia computer model used for contaminant movement modeling.

The January 31, 2006 report by TechLaw, Inc. advised the NMED that the neutron probe access holes installed below the buried wastes were a mistake because they did not monitor the breakthrough of moisture directly under the cover. The TechLaw Inc. report recommended the installation of instrumentation in the dirt cover to measure the breakthrough of moisture but the dirt cover installed over the dump did not include the instrumentation. 

 

A $275,000 April 14, 2010 Environmental Protection Agency Office of Inspector General (IG) Audit Report found that EPA Region 6 staffers had concerns similar to Citizen Action and Registered Geologist Robert Gilkeson about the lack of effective groundwater monitoring at the Sandia MWL dump. The EPA IG also found that the oversight report of the EPA Region 6 staff's for MWL dump groundwater monitoring concerns are still being withheld from Citizen Action and the public. The EPA Region improperly stamped its Oversight Report "Confidential" for national security purposes according to the OIG. Page 3 -- "Region 6 withheld information from the public regarding the MWL monitoring wells through:

  • discontinuation of record keeping,

  • misleading communications, and

  • inappropriate classification.")

The EPA IG found further that NMED and EPA Region 6 agreed that discussions about concerns for the monitoring well network at the MWL dump would not be documented in writing to avoid discovery of the documents by Citizen Action under the FOIA. (OIG report p.3 – "EPA conveyed its Oversight Review concerns regarding the MWL monitoring wells to NMED orally, and NMED was not required to formally respond to the technical team's concerns regarding the MWL monitoring wells.") Thus, EPA and NMED prevented public participation and withheld relevant facts from the public during the RCRA process for corrective measures. As reported by the EPA IG, EPA Region 6 stamped the oversight report "Confidential" thereby making the report unavailable under the Freedom of Information Act. 

Withholding relevant facts and reports allowed NMED and DOE/Sandia to proceed with constructing the dirt cover without opposition from an uninformed public without access to the facts. Citizen Action still has not obtained the Oversight Report from EPA Region 6.

(See, U.S. EPA Office of Inspector General, April 14, 2010. Hotline Report – Region 6 needs to improve Oversight Practices. Report No. 10-P-0100, April 14, 2010. ). 

A reliable network of groundwater monitoring wells was not provided at the Sandia MWL dump from the first well installed in 1988 to the four new wells installed in 2008. A total of nine contaminant detection monitoring wells and two background water quality monitoring wells were installed at the MWL dump over the 20-year period from 1988 to 2008. Table 1 below on the next page is a summary of the year of installation and current status for the eleven defective monitoring wells at the MWL dump. The unreliable monitoring wells MWL-MW1, -MW2, - MW3 and -BW1 were plugged and abandoned in 2008 and replaced with the four new unreliable monitoring wells MWL-MW7, -MW8, -MW9 and -BW2, according to Registered Geologist Robert Gilkeson.

(http://www.radfreenm.org/old_web/pages/GroundWaterProtection/SANDIA_MWL_DUMP_TEXT_JANUARY_2011.pdf pp-29-44). All of the six contaminant detection monitoring wells in the current monitoring well network (wells MWL-MW4, -MW5, -MW6, -MW7, -MW8 and –MW9 are unreliable and require replacement. See the following Table 1.

There are two zones of saturation below the Sandia MWL dump that require networks of monitoring wells. A reliable network of monitoring wells was not installed in either of the two zones. Figure 6 is a geologic cross section that shows the two zones of saturation below the MWL dump that require networks of monitoring wells. The upper zone is the water table in the fine-grained alluvial fan sediments. The deeper zone is the Ancestral Rio Grande Deposits (ARG Deposits) that are below the layer of fine-grained alluvial fan sediments that form a leaky confining bed above the ARG Deposits.

Table 1. Sandia MWL Dump Monitoring Wells

* The locations of the eleven monitoring wells are displayed on Figures 7. Year of Installation Well No. / Current Status the NMED 2004 Consent Order were not followed.

Reasons the monitoring wells do not furnish reliable and representative groundwatersamples.

  • Wells MWL-MW1 and -MW3 were the only two monitoring wells with any capability to detect contamination from the MWL dump.

  • Wells MWL-MW2, -MW5, -MW6 and -BW1 – four wells installed at incorrect locations and too distant from MWL dump to detect groundwater 

    contamination.

  • Wells MWL-MW1, -MW2, -MW3 and -BW1 – corroded stainless steel well screens prevented the detection of many contaminants.

  • Wells MWL-MW2, -MW3 and -BW1 – mud-rotary drilling method contaminated the three wells with bentonite clay drilling muds that prevented the detection of 

    many contaminants and prevented collection of reliable data on speed of groundwater travel.

  • Wells MWL-MW4, -MW5 and -MW6 – three wells with screens installed too deep to detect contamination at water table and measure elevation of water table.

  • Well MWL-MW5 – screen installed across two zones of saturation prevented well from having any use. In addition, the screen is contaminated with 

    bentonite clay/cement grout with properties to prevent the detection ofncontamination and prevent collection of reliable data on speed of groundwater travel.

  • Wells MWL-MW7, -MW8 and -MW9 – three wells installed in 2008 were drilled with improper methods with 30-ft screens installed too deep to detect 

    contamination and measure the elevation of the water table below the MWL dump.

     

  • Wells MWL-MW1, -MW2, -MW3, -MW4, -MW7, -MW8, -MW9 and -BW1 – the high-flow pumping methods purged the wells dry and highly aerated

    water samples were collected up to a week later. This sampling method removes volatile and trace metal contaminants from the collected water samples.

A DOE/Sandia 2008 field investigation showed a new large release of tritium and solvent contamination from the unlined trenches and pits at the Sandia MWL dump that was not investigated. DOE/Sandia performed a limited and incorrectly designed field investigation in 2008 that discovered a 10-fold increase of tritium contamination released from the wastes buried in the unlined trenches and pits at the MWL dump. The new release of contamination should have required implementing a comprehensive investigation to determine the nature and vertical and horizontal extent of the contamination in the vadose zone below the MWL dump before the dirt cover was installed over the wastes that were releasing the contamination.

The required careful investigation of the new contamination discovered in the vadose zone below the unlined trenches and pits was not performed. Instead, DOE/Sandia issued a final report (DOE/Sandia, August 2008) that did not recognize the new contamination and recommended the installation of the dirt cover above the buried wastes. The pertinent incorrect conclusion in the DOE/Sandia Report follows:

Because the findings of this investigation are consistent with the conceptual model of the MWL, the [dirt] cover should be constructed (p. ii). 

The findings of the 2008 field investigation were not consistent with the conceptual model of the Sandia MWL dump. The conceptual model was that the 10-fold increase in tritium contamination in the vadose zone below the MWL dump that was discovered in the 2008 field investigation was evidence that the unlined pits and trenches were still releasing contamination which may include other contaminants in addition to tritium. The dirt cover should not have been constructed until the nature and extent of the new contamination in the vadose zone below the MWL dump was fully understood.

The large increase in tritium concentrations measured in the DOE/Sandia 2008 field investigation is displayed in Figure 9 and is direct evidence of a new large release of tritium contamination and possibly other contamination including VOCs and heavy metals from the wastes buried in the unlined pits and trenches at the MWL dump. The actual increase in tritium and other contamination below the MWL dump is not known because of the sparse number of boreholes in the 2008 field investigation. None of the six boreholes were

  • 1). located close to the previous boreholes where high tritium concentrations were measured,

  • 2). located close to Trench A in the unclassified area and the 12 pits in the classified area where the large inventory of tritium wastes are buried or

  • 3). drilled to a sufficient depth to characterize the vertical extent of tritium and VOC contamination.

A new comprehensive investigation of the nature and extent of contamination in the vadose zone below the MWL dump is a requirement to protect public health and the environment and to ensure that the required network of monitoring wells are installed in the vadose zone below the unlined trenches and pits at the MWL dump for early detection of new releases of contamination for the required long-term monitoring.

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