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A tunable solid state laser system, chromium-activated forsterite (Cr3+: Mg2SiO4), which has the potential for tunability from 850-1400 nm, is introduced. The characteristics of the host crystal are examined. Laser experiments and measurements are presented, including the observation of pulsed laser action at room temperature. The possibilities of the system are also considered.
While supergranules, a component of solar convection, have been well studied through the use of Dopplergrams, other datasets also exhibit these features. Quiet Sun magnetograms show local magnetic field elements distributed around the boundaries of supergranule cells, notably clustering at the common apex points of adjacent cells, while more solid cellular features are seen near active regions. Ca II K images are notable for exhibiting the chromospheric network representing a cellular distribution of local magnetic field lines across the solar disk that coincides with supergranulation boundaries. Measurements at 304 A further above the solar surface also show a similar pattern to the chromospheric network, but the boundaries are more nebulous in nature. While previous observations of these different solar features were obtained with a variety of instruments, SDO provides a single platform, from which the relevant data products at a high cadence and high-definition image quality are delivered. The images may also be cross-referenced due to their coincidental time of observation. We present images of these different solar features from HMI & AIA and use them to make composite images of supergranules at different atmospheric layers in which they manifest. We also compare each data product to equivalent data from previous observations, for example HMI magnetograms with those from MDI.
The fate of space-generated solid wastes, including trash, for future missions is under consideration by NASA. Several potential treatment options are under active technology development. Potential fates for space-generated solid wastes: Storage without treatment; storage after treatment(s) including volume reduction, water recovery, sterilization, and recovery plus recycling of waste materials. For this study, a microbial characterization was made on trash returned from four recent STS missions. The material analyzed were 'Volume F' trash and other bags of accompanying trash. This is the second of two submitted papers on these wastes. This first one covered trash content, weight and water content. Upon receipt, usually within 2 days of landing, trash contents were catalogued and placed into categories: drink containers, food waste, personal hygiene items, and packaging materials, i.e., plastic film and duct tape. Microbial counts were obtained with cultivatable counts on agar media and direct counts using Acridine Orange fluorescent stain (AODC). Trash bag surfaces, 25 square cm , were also sampled. Direct counts were approximately 1 x 10(exp 6) microbes/square cm and cultivatable counts ranged from 1 x 10 to 1 X 10(exp 4) microbes/ square cm-2. Aerobic microbes, aerobic sporeformers, and yeasts plus molds were common for all four missions. Waste items from each category were placed into sterile ziplock bags and 1.5 L sterile DI water added. These were then dispersed by hand shaking for 2 min. prior to inoculation of count media or determining AODC. In general, cultivatable microbes were found in drinks, food wastes, and personal hygiene items. Direct counts were usually higher than cultivatable counts. Some pathogens were found: Staphylococcus auerus, Escherichia coli (fecal wastes). Count ranges: drink pouches - AODC 2 x 10(exp 6) to 1 X 10(exp 8) g(sub fw) (exp -1); cultivatable counts variable between missions; food wastes: Direct counts were close to aerobic plate counts. Counts ranged from 10(exp 6) to 10(exp 9) per g(sub fw). Identities of isolates from cultivation media were obtained using a Biolog Microbial ID System or microSEQ molecular ID methodology using an ABI3130 gene analyzer.
This document presents a description of solid waste management unit (SWMU) assessment activities that will be used to identify additional locations where per- and polyfluoroalkyl substances (PFAS) may have been used at the Kennedy Space Center (KSC). The activities described herein will also be used to identify potential off-Center sources of PFAS and potential background locations for PFAS within KSC.
With the recent incorporation of Mars Extravehicular Activity (EVA) into the 2025 NASA roadmap, Rapid Cycle Amine (RCA) technology advancement within the Exploration Extravehicular Mobility Unit (xEMU) applies to both the upcoming Lunar Artemis missions and future human exploration of Mars. The incorporation of commercial spacesuit vendors to service NASA’s crewed-space programs since 2021 has increased the demand for regenerable, RCA-based carbon dioxide (CO2) and humidity control adsorbents. The regenerable RCA subunit is the most advanced, long-term solution for CO2 removal and humidity control, enabling both lunar and Martian EVAs. The adsorbent selected for use within the RCA unit must exhibit sufficient storage stability and operational efficiency for prolonged missions. As XploSafe worked to simultaneously develop both a recirculating sub-atmospheric test rig and adsorbents for the RCA system within the xEMU, several novel adsorbents were evaluated for long-term storage stability in support of future extended-duration missions. The chosen materials were periodically evaluated by nuclear magnetic resonance (NMR) spectroscopy, thermal desorption-coupled with gas chromatography/mass spectrometry (TD-GC/MS), and CO2 adsorption to assess long-term storage efficacy across various environmental storage conditions. NMR spectroscopy was utilized by extracting the active CO2 adsorbing chemical from the solid support with deuterated solvent and comparing the spectra over time for degradation and change. The solid adsorbents were also analyzed via TD-GC/MS to reveal any potential off-gassing chemicals over time. Additionally, XploSafe’s breakthrough test rig was utilized to dose the solid adsorbents with a 585 BTU/h metabolic rate flow-equivalent CO2 stream and monitored for 0–99% CO2 breakthrough. The performance metrics from the breakthrough analysis were compared over the storage study duration for CO2 removal and humidity control. Xplo-SA9T was evaluated for 24 months, whereas two additional adsorbent variants, MMPA-Sorbent and LPEI-Sorbent, were each evaluated for 12 months.
Cell walls were prepared from the growing region of cucumber (Cucumis sativus) hypocotyls and examined by solid-state 13C NMR spectroscopy, in both enzymically active and inactivated states. The rigidity of individual polymer segments within the hydrated cell walls was assessed from the proton magnetic relaxation parameter, T2, and from the kinetics of cross-polarisation from 1H to 13C. The microfibrils, including most of the xyloglucan in the cell wall, as well as cellulose, behaved as very rigid solids. A minor xyloglucan fraction, which may correspond to cross-links between microfibrils, shared a lower level of rigidity with some of the pectic galacturonan. Other pectins, including most of the galactan side-chain residues of rhamnogalacturonan I, were much more mobile and behaved in a manner intermediate between the solid and liquid states. The only difference observed between the enzymically active and inactive cell walls, was the loss of a highly mobile, methyl-esterified galacturonan fraction, as the result of pectinesterase activity.
Changes at solid-liquid interfaces caused by adsorption from solution are discussed paying attention to the following aspects: (1) stability of adsorbed films and the structure of metal-additive-film-liquid interface and effect of adsorbate orientation. (2) chemical versus physical adsorption, (3) heat of adsorption, (4) adsorption of additives, (5) activated adsorption, effect of activating adsorbates, (6) displacement phenomena at solid-liquid interfaces, (7) competition of antiwear additives, their solvents, and water, (8) effect of adsorption on the orientation of liquid in the interfacial region, and (9) relation between the chemical nature of solid surfaces and their interaction with liquid lubricants. The relevance of the above adsorption phenomena to lubrication is discussed, referring where possible to specific examples.
Even though the executive branch has proposed terminating the Advanced Solid Rocket Motor (ASRM) program, NASA is proceeding with all construction activity planned for FY 1992 to avoid schedule slippage if the program is reinstated by Congress. However, NASA could delay some construction activities for at least a few months without affecting the current launch data schedule. For example, NASA could delay Yellow Creek's motor storage and dock projects, Stennis' dock project, and Kennedy's rotation processing and surge facility and dock projects. Starting all construction activities as originally planned could result in unnecessarily incurring additional costs and termination liability if the funding for FY 1993 is not provided. If Congress decides to continue the program, construction could still be completed in time to avoid schedule slippage.
Recent near-infrared spectroscopy of Kuiper Belt objects and Centaurs indicates considerable spectral diversity among them. Some have entirely bland spectra with no discernible spectral features (e.g., Chiron), while 5145 Pholus has a very active spectrum with absorption bands of H2O, CH3OH, and probably the mineral olivine present. In addition, the strong red color of Pholus indicates the presence of organic solids. Among the KBOs, 1993 SC has an active spectrum with the probably presence of hydrocarbons and possibly the ices of H2O and N2. The diversity among these spectra and the implications that such diversity has for models of the formation of the formation of the planets will be discussed.
NASA future missions demand safe, high specific energy (>400 Wh/kg) batteries. Current state-of-the-art (SOA) lithium-ion batteries (LIBs) can only provide ~150-200 Wh/kg in energy capacity, which is unable to meet NASA's future energy goals, and also pose safety issues due to the use of liquid flammable electrolyte. There are intense on-going development activities to increase battery energy density. The use of Li metal as an anode material has emerged as one highly attractive option for achieving high-energy, next generation batteries. This is because Li has many advantages. It is the lightest metal, but also has the highest theoretical capacity. It also has the lowest potential, which boosts whole cell voltage, and Li metal is 100% active material and requires no binder. Thus, Li metal is an ideal anode material for high energy battery chemistries. Lithium metal based advanced battery chemistries are envisioned to be mission enhancing and, in many cases, mission enabling for future space and aeronautic applications. However, the reliable use of this exceptionally high capacity anode in a commercial rechargeable battery has not been achieved due to safety and reliability concerns resulting from thermal runaway and short-circuit issues due to dendritic growth on the Li metal anode from lithium plating during charge-discharge cycles. A solid state electrolyte, such as garnet/ceramic or solid polymer nanocomposite electrolyte, is a promising approach to make Li metal safely cycling. The solid state electrolyte is non-flammable and eliminates leakage and fire hazard by replacing the liquid flammable electrolyte. However, the low-ionic conductivity and high interfacial impedance are the key issues to be overcome. In this presentation, the research activities on solid state electrolyte development funded by the NASA Advanced Energy Storage System program and by the NASA Center Innovative Fund will be presented, and the progress and results will be also discussed.
The fate of space-generated solid wastes, including trash, for future missions is under consideration by NASA. Several potential treatment options are under consideration and active technology development. Potential fates for space-generated solid wastes are: Storage without treatment; storage after treatment(s) including volume reduction, water recovery, sterilization, and recovery plus recycling of waste materials. Recycling might be important for partial or full closure scenarios because of the prohibitive costs associated with resupply of consumable materials. For this study, we determined the composition of trash returned from four recent STS missions. The trash material was 'Volume F' trash and other trash, in large zip-lock bags, that accompanied the Volume F trash. This is the first of two submitted papers on these wastes. This one will cover trash content, weight and water content. The other will report on the microbial Characterization of this trash. STS trash was usually made available within 2 days of landing at KSC. The Volume F bag was weighed, opened and the contents were catalogued and placed into one of the following categories: food waste (and containers), drink containers, personal hygiene items - including EVA maximum absorbent garments (MAGs)and Elbow packs (daily toilet wipes, etc), paper, and packaging materials - plastic firm and duct tape. Trash generation rates for the four STS missions: Total wet trash was 0.602 plus or minus 0.089 kg(sub wet) crew(sup -1) d(sup -1) containing about 25% water at 0.154 plus or minus 0.030 kg(sub water) crew(sup -1) d(sup -1) (avg plus or minus stdev). Cataloguing by category: personal hygiene wastes accounted for 50% of the total trash and 69% of the total water for the four missions; drink items were 16% of total weight and 16% water; food wastes were 22% of total weight and 15% of the water; office waste and plastic film were 2% and 11% of the total waste and did not contain any water. The results can be used by NASA to determine requirements and criteria for Waste Management Systems on future missions.
The Congressional committees that authorize the activities of NASA requested that the National Research Council (NRC) review the testing and quality assurance programs for the Advanced Solid Rocket Motor (ASRM) program. The proposed ASRM design incorporates numerous features that are significant departures from the Redesigned Solid Rocket Motor (RSRM). The NRC review concentrated mainly on these features. Primary among these are the steel case material, welding rather than pinning of case factory joints, a bolted field joint designed to close upon firing the rocket, continuous mixing and casting of the solid propellant in place of the current batch processes, use of asbestos-free insulation, and a lightweight nozzle. The committee's assessment of these and other features of the ASRM are presented in terms of their potential impact on flight safety.
A wet pressurized pyrolysis (wet carbonization) process has been invented as a means of producing activated carbon from a wide variety of inedible biomass consisting principally of plant wastes. The principal intended use of this activated carbon is room-temperature adsorption of pollutant gases from cooled incinerator exhaust streams. Activated carbon is highly porous and has a large surface area. The surface area depends strongly on the raw material and the production process. Coconut shells and bituminous coal are the primary raw materials that, until now, were converted into activated carbon of commercially acceptable quality by use of traditional production processes that involve activation by use of steam or carbon dioxide. In the wet pressurized pyrolysis process, the plant material is subjected to high pressure and temperature in an aqueous medium in the absence of oxygen for a specified amount of time to break carbon-oxygen bonds in the organic material and modify the structure of the material to obtain large surface area. Plant materials that have been used in demonstrations of the process include inedible parts of wheat, rice, potato, soybean, and tomato plants. The raw plant material is ground and mixed with a specified proportion of water. The mixture is placed in a stirred autoclave, wherein it is pyrolized at a temperature between 450 and 590 F (approximately between 230 and 310 C) and a pressure between 1 and 1.4 kpsi (approximately between 7 and 10 MPa) for a time between 5 minutes and 1 hour. The solid fraction remaining after wet carbonization is dried, then activated at a temperature of 500 F (260 C) in nitrogen gas. The activated carbon thus produced is comparable to commercial activated carbon. It can be used to adsorb oxides of sulfur, oxides of nitrogen, and trace amounts of hydrocarbons, any or all of which can be present in flue gas. Alternatively, the dried solid fraction can be used, even without the activation treatment, to absorb oxides of nitrogen.
This Air Sparge (AS) System Construction Completion, Performance Monitoring, and Long-Term Monitoring (LTM) Report presents activities conducted at the Paint and Oil Locker (POL) (Solid Waste Management Unit [SWMU] 067) and Supply Warehouse #3 (SW3) (SWMU 088) sites located at the Kennedy Space Center (KSC), Florida. Activities include implementation and Year 1 (Quarters [Q] 1 through 4) and Q5 operation, maintenance, and monitoring (OM&M) activities and performance monitoring results for the AS Interim Measure (IM) in the POL Southern Treatment Area, LTM results for the POL Northern Area and SW3, and supplemental direct push technology (DPT) sampling at both sites to support the LTM and performance monitoring programs. The timeframe for activities included in this report extends from August 2019 to August 2022. The scope for these sites currently includes two main components, which are documented within this report: (1) LTM at SW3 and POL Northern Area where an AS system began operation at these sites in May 2009 and June 2013, respectively, and subsequently turned off for both sites in March 2018 (during the previous reporting period); and (2) Active AS operations and performance monitoring in the POL Southern Treatment Area where an AS system was installed and began operation in 2021. The AS IM in the POL Southern Treatment Area was implemented between 2019 and 2021 to treat a chlorinated solvent groundwater plume that resulted from historic operations supporting the National Aeronautics and Space Administration’s (NASA) Space Program. The objective of the AS IM is to remediate groundwater within the treatment zone to support transition to monitored natural attenuation (MNA). The overall Corrective Action objective is to reduce concentrations of trichloroethene (TCE), cis-1,2-dichloroethene (cDCE), trans-1,2- dichloroethene (tDCE), and vinyl chloride (VC) present in groundwater to levels below their respective State of Florida Groundwater Cleanup Target Levels (GCTLs). The AS IM was installed in the POL Southern Treatment Area to target the high concentration plume (HCP), which includes a source zone (SZ) area where TCE was found to exceed 11,000 micrograms per liter (µg/L), and extend to a depth of 30 feet below land surface (bls).
The STS-84 mission flight crew, Cmdr. Charles J. Precourt, Pilot Eileen M. Collions, Payload Cmdr. Jean-Francois Clervoy (ESA), Mission Specialists Edward T. Lu, Carlos I. Noriega, Elena V. Kondakova, and Jerry M. Linenger can be seen performing pre-launch activities such as eating the traditional breakfast, crew suit-up, and the ride out to the launch pad. Also, included are various panoramic views of the shuttle on the pad. The crew can be seen being readied in the white room' for their mission. After the closing of the hatch and arm retraction, launch activities are shown including countdown, engine ignition, launch, and the separation of the Solid Rocket Boosters. The rendezvous with the Mir Space Station, along with onboard activities, and landing are included. Also included are shuttle-to-ground transmission between the crew and Mission Control and various earthviews.
Spectroscopic and laser properties of chromium-doped forsterite (Cr:Mg2SiO4) are reviewed and future directions in development of other Cr(4+)-doped tunable solid-state lasers are discussed. The unique property of chromium-doped forsterite is that the lasing center was identified as tetravalent chromium (Cr(4+)) substituting for tetrahedrally coordinated Si(4+). Development of chromium-doped forsterite laser may stimulate the generation of a new class of tunable solid state lasers based on tetravalent chromium as a laser active ion for the near-IR eyesafe spectral range. The criteria for the development of new Cr(4+)-based tunable solid-state laser crystals are discussed. We also present current research efforts to identify potential low field host crystals, such as silicates, titanites, and germanates, that may be doped with Cr(4+) as an active ion. These new laser materials are expected to cover the wavelength region from 1 - 2 microns, which may be of great technological importance.
Synthesis of the results of the Mariner 9 mission, as they pertain to polar volatiles, and comparison of them with a description of the solid-vapor equilibrium relations believed to be presently active on Mars. The discovery by Mariner 9 of extensive volcanic deposits on portions of the Martian surface suggests that the total amount of CO2 liberated to the surface probably exceeds that now present in the atmosphere. Thus excess CO2 in the solid form is to be expected in the polar areas. Although the simplified model of Leighton and Murray (1966), which predicts a permanent CO2 cap, has significant deficiencies both theoretically and observationally, the seasonal caps are composed of CO2, as predicted, excess CO2 is quite likely, and a permanent deposit of solid CO2 evidently is in equilibrium with atmospheric CO2. It is suggested that there must be a large reservoir of solid CO2 in gaseous equilibrium with the atmosphere, but buried immediately below the exposed residual water-ice cap. This reservoir is believed to be located near the north pole. The principal effect of such a reservoir is to average out annual and longer-term fluctuations in the polar heat balance.
The 2023 Performance Monitoring and Construction Completion Report (PM-CCR) presents the findings, observations, and results for Air Sparging (AS) operations and expansion activities, as well as sitewide groundwater monitoring for Launch Complex 39B (LC39B), Solid Waste Management Unit (SWMU) 009, at Kennedy Space Center (KSC), Florida. The reporting period for activities covered under this PM-CCR is from January 1, 2023, to December 31, 2023. At LC39B, AS operations began in 2017 in the area west of the launch pad, in the liquid oxygen (LOX) tank area located northwest of the launch pad, and in an area outside of the perimeter fence to protect nearby Outstanding Florida Waters (OFW). The LC39B AS system was installed with 279 AS wells to depths ranging from 23 to 60 feet below land surface (bls), including the sump, correlating to top of screen depths ranging from 20 to 57 feet bls. In December 2022, a total of 22 AS wells were abandoned to support launch pad crane operations, and in November 2023, the system was expanded with five additional AS wells installed to 13 or 17 feet bls near the LOX tank. The remedial objective of the LC39B AS Interim Measure (IM) is to actively decrease concentrations of contaminants of concern (COCs) in groundwater, specifically trichloroethene (TCE), cis-1,2-Dichloroethene (cDCE), and vinyl chloride (VC), to less than their respective Natural Attenuation Default Concentrations (NADCs), so LC39B can transition into a Long-Term Monitoring (LTM) program. This PM-CCR presents the following information for LC39B: • AS system operations and maintenance (O&M) (Year 7 of operation) from January 2023 to December 2023, to include AS trailer relocation in March 2023 and subsequent replacement and re-start in June 2023. • Construction completion details for AS system expansion, which included installation of five new AS wells and one new monitoring well in November 2023. As part of expansion activities, soil samples were also collected for petroleum analysis; no exceedances were identified, and no further investigation for petroleum is warranted. • Performance monitoring results for groundwater sampling events conducted in May/June 2023 (30 wells) and November 2023 (31 wells) in the AS IM area and in the Low Concentration Plume (LCP) areas located north and east of the launch pad for volatile organic compound (VOC) analysis. • Sampling results for one monitoring well, LOX-IW0012S, which is sampled for aluminum on an annual basis (May/June 2023). This well was resampled in November 2023 for both total and dissolved aluminum. Due to a communication error with the laboratory, the May/June 2023 sample was analyzed for total aluminum only. • Groundwater sampling results for per- and polyfluoroalkyl substances (PFAS) collected from seven monitoring wells during the May/June 2023 event to further investigate the Former Sewage Treatment Plant #6 and Percolation Pond area, west of the launch pad. O&M and performance monitoring results show that the AS system at LC39B is operating as designed and meeting performance criteria. Overall runtime was 45 percent (%) during the reporting period (January to December), but the operational runtime was 78% during the timeframe when the system could run (June to December). The most significant downtime contributor was post-launch crane operations following the Artemis launch on November 16, 2022, which lasted until June 2023. During that timeframe, the AS trailer at LC39B was relocated to another KSC remediation site (Wilson Corners) and was subsequently replaced with the AS trailer from the Paint & Oil Locker (POL) remediation site at KSC to resume AS system operations. Performance monitoring results in the AS IM and LCP areas continue to show reduction in COC concentrations over time when compared to baseline levels. In 2023, only one monitoring well (MW0048) detected a COC exceeding its NADC (VC at 740 micrograms per liter [µg/L]), which marks the baseline result for this new well installed during system expansion. Across the rest of the site, VC concentrations have declined or remained stable during the 2023 sampling events. Excluding MW0048, the highest VC result in 2023 was during the May/June sampling event with a concentration of 63 µg/L at MW0032, which is located near MW0048 and the AS expansion area by the LOX tank. TCE was detected in select monitoring wells in the IM area in 2023, but only two locations exceeded the State of Florida Groundwater Cleanup Target Level (GCTL): MW0032 (21 µg/L in May/June 2023 and 9.1 µg/L in November 2023) and MW0036 (5.0 µg/L in November 2023). MW0036 is also located near the LOX tank, on the north side, where the AS system is still operational (Zone Z4). cDCE and trans-1,2-dichloroethene concentrations were less than laboratory method detection limits or their respective GCTLs in all wells sampled in 2023. Near the OFW located northwest of the launch complex, all COC concentrations were less than laboratory method detection limits from monitoring wells (MW0039, MW0040, and LOXTA0002S) sampled in 2023. Aluminum results from LOX-IW0012S, which has been sampled routinely since 2006, detected a total aluminum concentration of 3,900 µg/L during the May/June 2023 sampling event. Results from the November 2023 event detected 5,700 µg/L for total aluminum and 5,500 µg/L for dissolved aluminum. These concentrations slightly decreased from the previous year but remain relatively consistent with historical detections. Aluminum will continue to be sampled on an annual basis at this well as results still exceed the GCTL of 200 µg/L and the Upper Limit of the KSC Background Concentration of 280 µg/L. PFAS results detected nine different PFAS compounds (out of 32 analyzed) from seven wells sampled. Two PFAS compounds, perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), currently have FDEP Provisional GCTLs of 70 nanograms per liter (ng/L). All seven samples collected resulted in concentrations less than the FDEP Provisional GCTLs for both PFAS compounds; no exceedances were observed. PFOS and PFOA also have assigned United States Environmental Protection Agency (USEPA) Maximum Contaminant Levels (MCLs) of 4 nanograms per liter (ng/L). None of the PFOS results exceeded the USEPA MCLs. PFOA was detected in two samples above the USEPA MCL at concentrations of 5.8 ng/L (ECS-IW0009I) and 5.5 ng/L (ECS-IW0009S). Three other PFAS compounds, perfluorohexanesulfonic acid (PFHxS), perfluoro-n-nonanoic acid (PFNA), and hexafluoropropylene oxide dimer acid (GenX), currently have USEPA MCLs of 10 ng/L. PFHxS, PFNA, and GenX were not detected at concentrations greater than their respective USEPA MCLs in any of the seven wells. PFAS compounds without FDEP Provisional GCTLs or USEPA MCLs were screened against USEPA RSLs. No other detections exceeded their respective USEPA RSLs. Additional PFAS sampling will be conducted as part of a future PFAS Site Assessment. Based on O&M activities and performance monitoring, the following is recommended for LC39B: • Continue with Year 8 AS system operation within Zone Z4, which includes the AS expansion area. Zone Z3, which has been off since 2018, should remain off as no rebound has been observed. Zones Z1 and Z2, which were turned off at the end of 2022, will remain shut down as monitoring well results have consistently been below GCTLs or have low-level detections with stable or decreasing trends (Meeting Minute 2402-M10, Decision 2402-D30). • Continue with performance monitoring in 2024 with the same monitoring well network as 2023, except with the addition of MW0048 in both semi-annual events. Baseline concentrations for this well were collected during the November 2023 performance monitoring event. Semi-annual sampling should be planned for the May 2024 and November 2024 timeframes (Meeting Minute 2402-M10, Decision 2402-D31). • Continue sampling monitoring well, LOX-IW0012S, for aluminum (total and dissolved) on an annual basis in May 2024. It is also recommended to re-develop this well prior to the next sampling event (Meeting Minute 2402-M10, Decision 2402-D32). The above recommendations for LC39B were presented at the February 2024 KSCRT Meeting, with Team consensus reached on the path forward. The contents of this PM-CCR were also presented at this meeting.