TEPCO to test spent fuel pool water desalination system

19 August 2011

TEPCO is planning a test run of a reverse osmosis system that desalinates water in the Fukushima Daiichi unit 4 spent fuel pool. The system will reduce the risks of corrosion of the stainless steel pool liner after seawater was poured in it (and in the unit 2 and unit 3 spent fuel pools) for cooling.

Truck-mounted spent fuel pool desalting facilities
Truck-mounted desalting facilities for the Fukushima Daiichi 4 spent fuel pool


The system takes water (about 3t/hr) from the alternative spent fuel pool cooling system (after cooling) and runs it to equipment mounted on five trucks. TEPCO expects that desalination will take about two months.

TEPCO said that it would also treat unit 2 and unit 3 spent fuel pool water, but began with unit 4 because of lower radiological contamination. Provided the test goes well, TEPCO will start the system up on 20 August.

An earthquake measuring magnitude 6.8 on the Richter scale struck offshore of Fukushima province on 19 August. Following the earthquake, TEPCO reported no abnormalities in each unit's major parameters, nor outside power supply, reactor water and nitrogen injection and spent fuel pool water injection.

Also, the second caesium decontamination line ('SARRY') in the water treatment system has begun full-scale operation. TEPCO has estimated its decontamination factor as on the order of 10,000x. Full operational volume was 50t/hr.



Executive summary

NEI agrees with some of the fundamental decisions that EPA has made in the Proposed Rule. First, NEI concurs with EPA’s decision to reject Options 2 and 3, which would require the regulated community to adopt closed-cycle cooling technology. Second, NEI agrees with EPA’s decision not to adopt a national best technology available (“BTA”) to address entrainment mortality. Selection of BTA requires consideration of many site-specific factors and, thus, such decisions are best made by the permitting authority on a case-by-case basis.
While we agree with EPA’s decision to reject Options 2 and 3, as well as the agency’s general approach to regulating entrainment, NEI respectfully submits that other aspects of the Proposed Rule are seriously flawed and lack sufficient support on the basis of the facts, documents, and data collected in the record. NEI’s specific recommendations regarding the proposed impingement and entrainment standards are provided below in Sections II.I and III. NEI’s detailed comments will focus on the following points:
IMPINGEMENT
- The adoption of national numeric impingement criteria is inappropriate. EPA’s numeric limits fail to adequately consider the large degree of site-specific variability that EPA has acknowledged and that render national “one-size-fits-all” criteria irrational and unworkable. NEI recommends that the EPA promulgate a final rule that allows the permitting authority to select BTA for impingement on a site-specific basis – in the same manner as BTA for entrainment would be selected under the Proposed Rule. In the alternative, if EPA decides to maintain national BTA for impingement, then NEI recommends that the agency adopt a true technology-based standard. Under such an approach, compliance would be achieved through either installation of a single, national BTA of modified traveling screens with a fish handling and return system; or a BTA chosen from a suite of appropriate technologies identified by the EPA, based on consideration of site-specific factors.
- If national numeric impingement criteria are maintained, the final rule must provide compliance flexibility to reflect regional and site-specific differences. Should the EPA seek to impose a single national standard for impingement, despite the significant site-specific variability across regulated facilities, the Agency must provide for flexibility in the imposition of individualized permitting standards and compliance measures. Without such adaptability, any national standard would be arbitrary. In addition, explicit clarification is needed to articulate unambiguously that the impingement mortality standards apply only to “species of concern.”


EPA’s national numeric impingement numbers (Option 1) were miscalculated. Even if national impingement numeric limits were appropriate, the specific limits adopted in this Proposed Rule are arbitrary for four independent reasons. First, the EPA derived the monthly and annual limits using an insufficient sample of data. Second, the annual limit selected uses an inappropriate methodology that fails to account for sufficient deviation


from the mean, which makes it likely that a substantial number of facilities that adopt the recommended BTA will, nonetheless, exceed the annual limit. Third, the annual limit fails to account for year-to-year variability. Fourth, the parameter selected focuses inappropriately on the percentage of impinged fish that died. This approach may penalize facilities with small numbers of fish deaths, and fails to credit the prior adoption of effective technologies that have already substantially reduced total impingement.
- EPA’s maximum 0.5 ft/second velocity design standard is too prescriptive. The proposed 0.5 ft/second velocity design standard is overly conservative and does not adequately account for site-specific variations that may make compliance with the limit unnecessary. Power plants that use closed-cycle cooling systems (e.g., cooling towers) should be permitted to exceed the 0.5 ft/second design limit, where site-specific conditions allow a higher intake velocity. Also, the Proposed Rule specifies that “[t]he maximum velocity limit must be achieved under all conditions.” 76 Fed. Reg. 22,283 (proposed § 125.94(b)(2)(ii)). The phrase “under all conditions” is problematic because certain operating conditions may result in temporary increases in intake velocity. While such episodes do occur, they are relatively rare and short in duration, and, thus, excursions into through-screen velocities greater than 0.5 ft/second would have minimal incremental impact on fish impingement and associated mortality. NEI recommends that EPA delete the phrase “under all conditions” from the proposed § 125.94(b)(2)(ii) and that the final rule be aligned with the more reasonable velocity standard contained in the Phase I Rule applicable to new facilities.
- Plants using closed-cycle recirculating systems should not be burdened with additional compliance studies or equipment deployment. The Proposed Rule would require facilities that elect to comply with the maximum 0.5 ft/second velocity standard to install additional technologies to reduce the potential for entrapment of fish and shellfish in the cooling water intake system, and further reduce the impingement mortality of fish and shellfish by installing barrier nets or their equivalent and modifying existing traveling screens. Such additional requirements are unnecessary, would yield minimal incremental benefits in terms of reducing impingement mortality, and result in a more stringent set of requirements than those applicable to new facilities under the Phase I Rule. NEI recommends that the EPA revise this portion of the regulations to require additional protective measures (beyond closed-cycle cooling) only in situations where threatened or endangered species are present and susceptible to impingement.
- EPA has underestimated the costs associated with its national numeric impingement numbers (Option 1). EPA discussed, but failed to quantify, the ongoing compliance costs arising from the presumably available adaptive management associated with its selected BTA and stipulated as necessary to meet the annual and monthly numeric limits.
- EPA’s belated attempt to analyze the non-use benefits of its rule deprives the regulated community of a meaningful opportunity for public comment. Despite having at least 15 years to compile the relevant data, EPA still does not have sufficient data to estimate the non-use benefits associated with the impingement rule. It thus lacks a basis for having


already concluded that those benefits justify the costs of the Proposed Rule. Moreover, while EPA indicated it would incorporate the new survey data after the close of the comment period on the Proposed Rule through issuance of a Notice of Data Availability, the OMB did not approve EPA’s request for a national survey. Instead, OMB opted to approve only a regional pilot study at this time. Therefore, the national benefits data is unlikely to be available before the rule is finalized. It is unlikely that stakeholders will be given an adequate opportunity to comment on this additional data and, even if they are, it seems even more unlikely that EPA will have time to meaningfully consider such comments given the prescribed schedule for completion of the rulemaking. The regulated community must be provided an adequate opportunity to comment on that critical information and its effect on EPA’s selection of regulatory options.
- EPA has failed to provide any rational basis explaining how the costs of Option 1 are justified by the benefits. After professing the importance of conducting cost benefit analysis for its Section 316(b) rule, EPA has failed to explain how the impingement BTA costs under Option 1 are justified by the benefits, when the costs are 21 times the monetized benefits and the rule results in a negative net benefit of $366 million annually and negative net benefit of $9.5 billion in total over the next 50 years. Issuing the Proposed Rule, despite the drastic discrepancy between costs and benefits, is inconsistent with any reasonable reading of Executive Order 13,563, which “directs agencies to the extent permitted by law, to propose or adopt a regulation only upon a reasoned determination that its benefits justify its costs recognizing that some benefits and costs are difficult to quantify.” 76 Fed. Reg. at 22,207 (citing E.O. 13,563, Sec. 1(b)(1))(emphasis added).
ENTRAINMENT
- EPA must articulate a meaningful decision criterion to govern the site-specific, cost-benefit analyses required by the rule. Although NEI agrees with EPA’s site-specific approach to evaluating entrainment controls, the agency must specify that permitting authorities should impose such controls only if the quantifiable costs are comparable to the quantifiable benefits. More specifically, NEI believes that, at a minimum, the permitting authority should demonstrate that any additional entrainment control requirements will yield a positive net benefit before imposing such requirements.
- NEI agrees with EPA’s decision to reject Options 2 and 3, both of which would require adoption of closed-cycle cooling to address entrainment. As EPA acknowledged, requiring a retrofit of closed-cycle technology would be incredibly expensive and “is not practically feasible in a number of circumstances.” 76 Fed. Reg. 22,207. Moreover, a nationwide retrofit mandate would have serious adverse environmental consequences in terms of particulate matter air emissions and freshwater consumption. As described below, retrofitting of closed-cycle cooling technologies is especially problematic for nuclear reactor facilities, which deliver a steady flow of electricity output.

New units at existing facilities should be treated like existing units located at the same site, with the provision that impingement and entrainment BTA are determined simultaneously by the nine factors that must be considered for entrainment. Closed-cycle cooling should not be categorically designated as BTA for new units at existing facilities. The decision-making criteria used to determine entrainment BTA for existing units on the very same site as a proposed new unit are appropriately site-specific. If the Proposed Rule is finalized in its current form, a permitting authority may be forced to impose closed-cycle cooling as BTA for a new unit, after determining that – based on the nine site-specific factors required to be considered for entrainment – closed-cycle cooling is not appropriate for an existing unit at the very same site.





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