SECTION III – THE DIRT COVER REMEDY CHOSEN FOR THE MWL DUMP IS INADEQUATE TO PROTECT HUMAN HEALTH AND THE ENVIRONMENT
A brief history of permitting reports for the MWL dump is as follows:
In September 1990, Sandia/DOE published the Report of the Phase 2 RCRA Facility Investigation of the Mixed Waste Landfill.
In September 1996, Sandia/DOE published the Report of the Mixed Waste Landfill Phase 2 RCRA Facility Investigation.
In May 2003, Sandia/DOE published the MWL Corrective Measures Study.
- In November 2005, Sandia/DOE published the MWL Corrective Measures Implementation Plan http://www.nmenv.state.nm.us/hwb/snlperm.html#CMIWP
In November 2005, Sandia/DOE published the Long Term Monitoring and Maintenance Plan. http://www.nmenv.state.nm.us/hwb/snlperm.html#LTMandMPlan
[Note: the LTMMP was issued in advance of the Corrective Measures Implementation Report and must be reissued.]
In January 2010, Sandia/DOE published the Corrective Measures Implementation Report.
The NMED sent Sandia/DOE a revised draft permit dated April 12, 2011, but did not provide notice to the public about the revised draft permit being sent to Sandia/DOE. The revised draft permit is not referenced or available on the main NMED website. ftp://ftp.nmenv.state.nm.us/hwbdocs/HWB/snl/SNLRevised_Draft_Permit/
The New Mexico Environment Department (NMED), Sandia Labs and DOE's remedy decision for the MWL dump has been limited to the installation of a dirt cover over the wastes, Long-term Maintenance and Monitoring and Stewardship. Earlier information about defective groundwater monitoring wells that provided unreliable and unrepresentative data for the decision to leave the radioactive and hazardous mixed waste in the MWL was not included in the above reports. There were numerous internal documents of the Department of Energy, the NMED, the US EPA, and Los Alamos National Laboratory that contained information about the MWL dump's groundwater monitoring network that did not meet state and federal regulatory standards for groundwater monitoring.
In 1998 a decision was made by NMED to treat the MWL dump as a Solid Waste Management Unit ("SWMU") rather than as a "regulated unit." The DOE/Sandia annual groundwater report describes the requirements for RCRA Corrective Action as follows:
2.0 REGULATORY CRITERIA
Historically, the NMED Hazardous Waste Bureau has provided regulatory oversight of the MWL as Solid Waste Management Unit (SWMU) 76 under the Hazardous and Solid Waste Amendments module of the facility Resource Conservation and Recovery Act [RCRA] permit. The NMED confirmed that the MWL is properly designated as a SWMU (Dinwiddie June 1998) and, as such, must comply with the corrective action program defined in Title 20, New Mexico Administrative Code, Section 4.1.500, incorporating Title 40, Code of Federal Regulations, Section § 264.101. The requirements for corrective action at the MWL, including those for groundwater monitoring, are established through the corrective measures process (p. 2-1).
The MWL dump is actually a "regulated unit" by definition because it received hazardous waste after July 26, 1982. (40 CFR § 264.90(a). In the author's opinion, the MWL dump has been improperly classified as a Solid Waste Management Unit (SWMU) for closure under Corrective Action. Special requirements for closure and post-closure permits apply to regulated units especially where the regulate unit is leaving wastes in place. 40 CFR §270.1 (c) requires that owners and operators of landfills that received waste after July 26, 1982 must have post-closure permits, unless they demonstrate closure by removal or decontamination or obtain an enforceable document in lieu of a post-closure permit. If a post-closure permit is required, the permit must address groundwater monitoring, unsaturated zone monitoring, corrective action and post closure care requirements. No post closure permit has been submitted for the MWL dump which is leaving wastes in place.
The 2004 Consent Order does not constitute an enforceable document to be used "in lieu of" a post closure permit for the MWL dump. The Consent Order provides that its use is limited to corrective action and that the closure and post-closure requirements of 40 CFR Part 264, Subpart G [40 CFR §264.118 et seq.] for operating units will be addressed in the future Hazardous Waste Facility Permit and not in the Consent Order. (Consent Order III.W.1(2), p.33). The Consent Order precludes itself from being used in lieu of the closure and post closure requirements.
The Consent Order (p.4) states that the MWL is an un-permitted landfill. Thus by its own terms the Consent Order does not constitute a substitution for a RCRA permit for the MWL. A valid RCRA permit consists of a Part A application and a Part B final permit. (40 CFR 270.1(b)). The purposes and scope of the Consent Order encompass only those of corrective action.
The Consent Order does not address radionuclides or the radioactive portion of mixed waste. (III.A, p.14). DOE Orders 435 (Performance/Composite Analysis), 450.1 (Environmental Management System), and 5400.5. Radionuclides disposed of at the MWL dump have not been adequately addressed.
Transuranic Waste (TRU)—the SWIMS database indicates that about 50 cu ft of TRU waste containing 1.2 mCi of total activity was disposed of at the MWL. Memoranda and Waste Management Site Plans from the early 1970s indicate that the amount of TRU waste could be as high as 600 cu ft. The major contaminants included in this waste category are Pu-238 and Pu-239. (A Preliminary Human Health Risk Assessment for the Mixed Waste Landfill, Sandia National Laboratories, 1995, p. 12)
Pu-238 and Pu-239 in the surface run-off pathways away from the MWL dump were not investigated. With a half-life of 87.7 years for Pu-238 and 24,100 years for Pu-239, both of these contaminants should be of concern along the surface soil pathway.
Characterization was not done with the surface soil samples for plutonium as required in the Work Plan at the Mixed Waste Landfill during the RCRA Facility Investigations (RFI) Phase 1 and Phase 2. The Phase 1 Work Plan for an Expanded Site Assessment at the Mixed Waste Landfill (July 1989) by Ecology and Environment, Inc., (Table 3-2, p. 3-11) stated 197 surface soil samples were to be collected for Tritium, Gross Beta, Gamma Spectrometry, Isotopic-Uranium, and Strontium 90 if gross beta and the gamma isotopic scan indicate its presence.
The number of surface soil samples collected did not meet the 1989 Work Plan requirements and many samples were lost. The Phase 1 Report (p.3-24) states:
"A total of 164 surface soil samples including duplicates and blanks were collected at the MWL. The workplan specified the collection of 182 samples. Samples could not be collected where surface obstacles prevented access (i.e., above ground storage casks, disposal pits and associated concrete, steel, or wood caps, unyielding ground), or near areas of excessively high radiationmarked areas (previously roped off by SNL). Originally, all of the samples were to be analyzed for tritium, gross beta activity, gamma emitters (gamma spectroscopy), isotopic uranium, and isotopic plutonium. Ten Percent of the samples (randomly selected) were analyzed to determine if the radiological parameters could be determined. The remainder of the samples were lost bythe laboratory. The actual analyses were for tritium, gross beta activity, gross alpha activity, gamma emitters, and isotopic uranium." (Emphasis added).
On the contrary, however, The RFI Phase 1 Report at Table 5-6 (p. 5-11) shows that gamma emitters were not analyzed. In addition, the analytic results for gamma emitters are not presented anywhere in the RFI Phase 1 or Phase 2 Reports.
This statement is an indication that high levels of surface soil contamination were present and were not characterized for plutonium and many other contaminants, especially given the fact that only ten samples were analyzed. The ten samples, moreover, did not analyze for nuclear weapons related contaminants other than tritium, Ra-226, U-234, and U-238 (Table 5-6, p. 5- 11).
None of the later sampling in the RFI Phase 2 looked for plutonium or other radionuclides, with the exception of tritium. Plutonium was detected in the surface soils from a limited study of the closure of an Interim Status Storage Unit. (Also, see below). The gamma isotopic scan was not performed as required by the RCRA Phase 1 Workplan. The Phase 1 Report (p.3-25 and Table 3-4) showed that the Workplan activity for Surface Soil Sampling was for -- "182 Samples to be collected for analyses for Tritium, Gross Beta, Gamma Spectrometry, Isotopic-Uranium , and Isotopic Plutonium. 100% Analysis of samples." The Completed work was -- "164 samples collected for Analyses for Tritium, Gross Alpha/Beta activity, Gamma Spectrometry, and Isotopic Uranium. Iso-Plutonium only if elevated gamma readings noted. Only 10% analyzed in 1989. Remainder to be analyzed in Phase II."
The remaining 90% of the samples were supposed to be analyzed in Phase 2. Apparently the laboratory lost the samples. (See fn 1). In the Phase 2 (p. 4-29) surface soil sampling, however, there is indication only that surface soil samples were collected for tritium. The remaining analysis of Phase 1 sampling was apparently not accomplished.
The failure to accomplish the RCRA Workplan for Phase 1 and 2 gives no confidence that soil surface contamination from plutonium or other radionuclides does not exist because only 10 samples were actually analyzed and for a limited analytical suite.
Failure to conduct adequate surface soil sampling precluded risk analysis for both the surface runoff pathway and for airborne emissions inhalation pathway. The Preliminary Human Health Risk Assessment for the Mixed Waste Landfill, Sandia National Laboratories, Albuquerque, New Mexico (January 1995) was based on the limited and insufficient data from the RFI phase 1 and 2 surface soil sampling. "No surface soil sampling was performed during the RCRA Facility Investigations Phase 1 and Phase 2 for RCRA heavy metals." (P.9).
The 1995 Risk Assessment states further: "In addition, the lack of surface soil data precludes modeling the potential airborne emissions from the site. The potential pathways of concern for the future resident include inhalation and absorption of tritium, external radiation, and ingestion of groundwater. Inhalation of radioactive air particulates was not assessed for the same reason as for the worker scenario. Incidental ingestion of soil, and ingestion of contaminated food also were not assessed because surface soil data have not been collected." (Emphasis supplied).
The RFI Phase 2 Report (p.7-6) states "Surface soil sampling for radionuclides showed all values to be below the 95thpercentile or UTL background level, with the exception of tritium." However, the only data presented in the Phase 1 and 2 reports is from 10 samples that did not adequately characterize for radionuclides other than tritium.
The DOE/Sandia has installed a dirt cover over the MWL dump wastes. Long-term monitoring and maintenance and stewardship have yet to be approved or implemented.
Dirt Cover. In December 2004 a public hearing was held for the NMED recommendation to leave the toxic wastes buried in unlined trenches and pits at the Sandia MWL dump below a dirt cover (Pruett, 2005). On May 26, 2005 NMED Secretary Ron Curry issued a Final Order approving a Corrective Measures Implementation Plan (CMIP) for the installation of dirt cover over the Sandia MWL dump to keep rain and moisture out.
The dirt cover is an experimental 3-ft. layer of soil called an "evapo-transpirative" cap that was installed by running heavy compaction equipment above the dump wastes. This simply means that any excess water will be evaporated using native vegetation that will take up moisture through their roots and suck it away from the landfill into the air. A fiber optic system will be installed in the soil layer in a snake-like fashion to measure the moisture in the soil. In the event subsidence occurs—the settling or caving in of soil due to underground air pockets—it will simply be taken care of by throwing more dirt on top of the cap. Air pockets can form as a result of un-compacted waste dumped into the landfill. Subsidence can also result from decreasing water levels in the aquifer and earthquakes.
Although a dirt cover has been placed over the dump, it will not be effective for long term protection of the long lived wastes in the dump that can enter air and water. The New Mexico Environment Department sued Citizen Action to keep a 2006 TechLaw, Inc. report secret until late 2009. The TechLaw report reveals flaws in the dirt cover construction for long term protection and rejects Sandia's computer modeling for movement of the dump's wastes. The TechLaw, Inc. report can be viewed at here.
In January 2010 a Corrective Measures Implementation Report ("CMI Report") regarding the details of completion of the installation of the dirt cover was provided to NMED by Sandia.
Citizen Action furnished comments on the CMI Report that may be reviewed here. The cover is ineffective. Dangerous wastes have already begun to enter the groundwater. Nickel, chromium, cadmium and nitrates appeared in older defective monitoring wells that were installed decades ago.
Solvents were placed in the MWL dump. Solvents can dissolve other waste substances found in the MWL dump and form a uniformly dispersed mixture.
"Chemical wastes include acids, solvents, trichloroehylene (TCE), carbon tetrachloride, and scintillation cocktails. Other wastes disposed of in the classified area include uranium, thorium, plutonium, enriched lithium, various (leaky and intact) sources, plutonium-contaminated wastes from various facilities, and plutonium-contaminated nuclear weapons test debris." - Appendix D, SNL Site Health and Safety Plan Form, 1992 (FOIA 116).
"Chemicals contaminated with radioactive materials were disposed of in the radioactive acid pit is pit until about 1969. Contaminated chemicals included solvents, acids, trichloroethylene and carbon tetrachloride." - Interview with former SNL employee Frank Statzula (FOIA 58).
Soil vapor studies conducted in 2007 show that cancer causing volatile organic solvents are moving deeper beneath the MWL dump. DOE/Sandia computer studies in 1995 and 2007 predicted the groundwater is contaminated now with PCE. The same type of solvent wastes found in the MWL dump such as TCE and PCE were placed in the Chemical Waste Landfill dump, contaminated the groundwater and had to be excavated.
The presence of the dirt cover can actually accelerate the movement of solvents to the groundwater. "However, it is ironic that a cover that is effective in minimizing soil moisture in the landfill can also contribute to an increase in vapor phase transport of volatiles such as tritium." (Review of Sandia National Laboratories/New Mexico Evapotranspiration Cap Closure Plans for the Mixed Waste Landfill by Tom Hakonson, Ph.D., Environmental Evaluation Services, LLC).
Hakonson addresses other problems for dirt covers:
"Buried waste can be mobilized to the ground surface through plant roots and animals and insect burrowing can dramatically increase infiltration of water into landfill with covers as thick as those proposed;
"Vertical transport of contaminants to the ground surface by biota may be small on a short time scale, but over many decades these processes may become dominant in mobilizing buried waste; " The long-term consequences of biointrusion into low level waste landfills located in arid areas estimated that doses to humans resulting from biological transport were as high as doses calculated from a human intrusion scenario (Pacific Northwest Laboratory).
Long-term monitoring. In addition to monitoring the ground water at the MWL dump, Sandia installed three angled holes drilled to a depth of 200 ft. on the east and west sides of the landfill. Probes inserted in the boreholes are supposed to monitor the area of unsaturated soil located between the surface and the ground water called the vadose zone. The vadose zone monitoring proposed in the DOE/Sandia Long-Term Monitoring and Maintenance Plan is inadequate because the three vadose zone monitoring wells are too few and are located distant from the hot spots in the MWL dump. Unfortunately, the NMED HWB has not required vadose zone monitoring beneath the unlined trenches and pits at the MWL dump.
A network of seven groundwater monitoring wells are proposed for long term monitoring. As discussed below, the proposed groundwater monitoring wells are defective and did not furnish evidence of no contamination to the groundwater. The data furnished from the groundwater monitoring network did not furnish a factual basis for leaving the wastes under a dirt cover.
The Sandia Long Term Monitoring and Maintenance Plan (LTMMP) preceded the issuance of the Corrective Measures Implementation Report for the MWL dump. The LTMMP is required to be submitted within 180 days after the NMED approval of the CMI Report. For this reason the LTMMP will need to be resubmitted for public comment. Citizen Action's public comments are on NMED's website here.
Stewardship. Stewardship is a term conceived by DOE that means instead of cleaning up contaminated sites, DOE will utilize physical and institutional controls - signs, fences, buffer zones, zoning ordinances, land use restrictions, environmental covenants, record-keeping, access control, surveillance - and other activities necessary to "protect human health and the environment at DOE sites that have residual waste or contamination" (DOE Report To Congress On Long-Term Stewardship p.1-2).
The period of stewardship for the MWL set by regulation is only for a period of 30 years. The MWL dump wastes will remain dangerous for tens of thousands of years due to the presence of transuranics such as depleted uranium, plutonium and americium. There are no long term trust funds in place for financial assurance for care the MWL dump. Sandia is treated as exempt from requirements for closure and post closure care financial assurance requirements.
RCRA requires that a landfill be closed by clean closure by decontamination and removal of wastes. If wastes are to be left in place a closure and post-closure permit are required or an enforceable document must be obtained. As described below, no closure/post-closure permit exists for the MWL dump.
Industrial land use. Sandia and DOE's long-term plan for the dump is to impose land use restrictions and designate the dump for industrial usage. This means that residential housing will not be allowed at the area of the dump; however, if the landfill is approved for industrial use people will be spending less time around the dump decreasing their chances of contracting cancer. The NMED has approved this method of dealing with waste sites.
A problem arises from the potential future intermingling of land for residential housing with land allowed for restricted industrial use. Allowing the degradation of the drinking water aquifer to an industrial standard where the groundwater will be used for residential usage creates a conflict.