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Selected Likely Key Issues in the Anticipated TA-54 Low-Level Waste Disposal Performance Assessment for Los Alamos National Laboratory
1/25/06 DRAFT Greg Mello
· Process issues:
o There has been no provision for independent experts or the Northern New Mexico Citizens Advisory Board (CAB) to be part of pre-publication formal peer review.
o The Performance Assessment (PA) is, upon information and belief, three years overdue. What penalty, if any will be imposed on the contractor for this delay? It is our judgment that the previous PA did not meet industry standards. Will this one? If it does not, what penalty will ensue?
o Upon information and belief, the primary author of the draft PA at Los Alamos National Laboratory (LANL) has been taken off the project just prior to completion. Why?
o How will the PA process and its incipient findings be integrated into the life-cycle cost analysis required by DOE and Congress, into closure and post-closure permitting under the Resource Conservation and Recovery Act, and into DOE’s own proposed expansion plans in an open and publicly-accountable manner?
o What steps, if any, will DOE take to break down the de facto secrecy that surrounds its environmental decisionmaking at LANL, including the development of this PA?
· Content issues:
o Will DOE analyze risks to a single representative individuals or the total risk (i.e. hazard) to populations? If the former case, “dilution [can appear to be] the solution to pollution.”
o Will the total hazard, if evaluated, be evaluated for 1,000 years, 10,000 years, or what period? Will the total hazard be integrated over time? Example: for Pu-239, the first 1,000 years comprises only ~ 3% of the integrated hazard over all time.
o Will the total hazard be evaluated for distal populations downstream and downwind? Will aerial resuspension, sediment transport, slow aqueous solution from sediments, and other processes be considered?
o Given that total loss of containment at Area G is certain, will the PA attempt to bound the shape of the loss vs. time curve with explicit assumptions and analyses?
o What are DOE’s assumptions for the duration of site maintenance and control? This was a particularly unrealistic aspect of the previous PA.
o What land use and intrusion scenarios will be considered? It is impossible to predict the probability of willed or inadvertent intrusion because these potential events are not subject to probability. Willed human actions are by their nature unpredictable. Farming and residential scenarios are historic, therefore realistic, and must be included, as must “mining” of waste pits for the metals, fissile materials, and other useful materials they contain by the ton.
o Infiltration through waste at Area G is enhanced today in parts of Area G by a cobble mulch and partially impervious covering (the tents), much to the hydrologic detriment of the site. What percent impervious covering will be assumed for the future, or will a “natural” surface, which is a possibility but by no means the only possibility, be assumed?
o What subsidence will be assumed for pits and shafts? Even massive concrete must be assumed to have a finite lifetime, at most 300 years.
o What role will be assigned to deflation by wind, followed by run-on into depressed zones?
o Burrowing animals can move great volumes of materials. To what extent will they do so here?
o Trees are currently absorbing and shedding radionuclides in the vicinity of Area G, as LANL studies have shown. Since the permeability of the waste cells will be orders of magnitude greater than the surrounding tuff, how will the intrusion of trees be permanently barred from the waste cells?
o The bottoms of the waste pits are 0 and 50 feet above the level of the stream and springs in Pajarito Canyon. How far is this waste, and how far will it be, from groundwater now, and in the future? The answer is not “900 ft.”
o The hydraulic conductivity of waste pits and shafts is likely to be roughly 3-5 orders of magnitude different than the surrounding tuff. This could have a number of implications, including: recurring higher moisture content in pits and shafts, preferential deep rooting by all types of plants, preferential choice by burrowing animals, and potential direct infiltration to groundwater.
o While mass wasting of these mesas is slow, it may not be slow in seismic events, renewed pluvial climates, or in the event of renewed volcanism. How will the integrity of caps weather such events, which are in aggregate quite likely, given a sufficiently long time?
o It has become impossible to predict the climate at this or any site. While drier climates are most likely, even a pluvial climate for North America, while not the most likely scenario, cannot now be dismissed for even 100 years from today, given the rapid melting of Greenland ice and observed 30% diminution of the North Atlantic current. (A recent Inter-Governmental Climate Panel (IGCP) study estimated that precipitation in New Mexico might be, in the coming century, 30% greater than today, just on the basis of warming, not counting any ocean circulation changes.) Aquifer recharge in arid and semi-arid situations is an extremely sensitive function of quantity, timing, an nature of precipitation; a 50% increase in precipitation could cause a many-fold increase in aquifer recharge at TA-54 – and hence in future aquifer contamination and biological activity at and in the dump sites and waste pits.
o It has proven impossible to model and predict fracture flow in semi-porous systems like tuff. This, in fine, is the conclusion of the National Academy of Sciences, of studies at Yucca Mountain, and the conclusion of a prestigious independent expert hired by the New Mexico Attorney General’s office.
In sum, there are three issues (shown in bold above) which cannot be resolved scientifically at TA-54, no matter how much money and time are spent. These uncertainties, taken as a whole, make it very difficult to bound the total risk at TA-54 below some large level based on worst-case scenarios.
· LANL environmental demerits relative to other disposal sites, in quick summary form:
o LANL is a much wetter site than NTS.
o NTS is already very badly and irrevocably contaminated.
o LANL overlies a public drinking water aquifer.
o TA-54 is upstream from surface water utilized as public drinking water source.
o TA-54 is immediately adjacent to springs, intermittent streams, and active flood plains.
o TA-54 consists of fractured, porous rock.
o TA-54 disposal pits have a demonstrated ability to convey contaminants to great depth.
o Aquifer contamination has already occurred near TA-54, for whatever reason.
o LANL is near growing population centers, and probably will be as long as the sky is blue and the Rio Grande continues to flow
o TA-54 is immediately adjacent to world-class antiquities and Indian sacred sites which are very important for cultural survival, some of these sites must even be destroyed to expand disposal facilities.
o The use of cap technology to overcome inherent problems at the site must be questioned in light of the site’s serious seismic history (the site is capable, according to LANL, of vertical acceleration > 1 g, and of earthquakes of magnitude 7).