THE CASCADE

Carries out the initial phase of the enrichment process. It is equipped with 80 cells, each of which has 8 isotopic stages, for a total of 640 stages. All cells contain the largest-size equipment in the system (designated X-33 or 000). As in the other two process buildings, the enrichment stages are on the second floor, and the control rooms and other auxiliary systems and equipment on the ground floor. The two floors provide a total of 65 acres of floor space.

A Low Assay Withdrawal Station (LAW) is located in the west-central section of the building. Installed during a cascade upgrading process, it provides a second station for the removal of reactor-grade material. (The original low-assay withdrawal station was the Extended Range Product Station in X-326.) LAW can also withdraw tails.

Carries out the intermediate stages of the enrichment process. Thus it handles UF6 uranium hexafluoride with higher and with lower assays than X-333. It is equipped with 1100 stages. Five hundred stages (50 cells) are equipped with X-31- or 00-size equipment, and six hundred stages (60 cells) with X-29- or 0-size equipment. Two floors provide a total of 55 acres of floor space.

A tails withdrawal station, located in the northeast corner of the building, was part of the original plant design. It has been modified to enable it to withdraw product as well as tails.

The Portsmouth cascade is capable of enriching uranium to 97% uranium 235. X-326 carried out the final and highest stages of the enrichment process. Thus it has the smallest process equipment. The building is equipped with 2340 stages, 720 stages (60 cells) with X-27-size equipment and 1620 stages, including purge stages, with X-25-size equipment. The building’s two floors have a total of 58 acres of floor space.

A withdrawal station known as the X-326 product withdrawal station is located on the ground floor in the southwest corner of the building. It was designed for withdrawal of HEU and, like the Extended Range Product Station, was part of the original plant design.

The Extended Range Product Station (ERP) is located in the northeast corner of the building. This station was considered safe for all assays but is usually used for the withdrawal of low-assay UF6.

Purge facilities are located in the south end of the building. It is necessary to reduce the concentration of light contaminants in the UF6 stream before the upflow enters the small X-25 equipment, which has an interstage flow that would be too small to handle them. Therefore two purge cascades are used, each originally composed of five cells. The side purge, is on the east side of the south end of the building; the top purge, beside it, on the west side. Under normal operating conditions, the side purge removed 90% of the light contaminants present. The top purge removed the remaining 10% and any in leakage into the purge equipment. Essentially all of the upflow of Freon coolant was removed at the top purge [DOE 77].

The X-326 L Cage stores "specific levels of radioactively contaminated waste" under special security requirements [DOE 00a].

Production of HEU came to an end in 1991, and 1680 stages were retired in place. They were cleaned of large deposits and mothballed between FY 1993 and FY 1998 A total of 240 X-27-size isotopic stages and 180 X-25-size purge cascade stages remain in operation in 2000. They are used for product withdrawal and side feeding.

From early 1997 to mid-1998, the active stages in X-326 were also used to downblend 14 MTU of HEU stored at the plant. The downblending took place as the result of a memorandum of understanding between DOE and USEC signed in 1994 and was part of "a program to reduce PORTS inventory of HEU." The HEU-UF6 in storage was refed/down-blended; and other uranium bearing materials of greater than 20% assay were shipped off site [BJ 00].

December 9, 1998, a fire largely destroyed one cell and damaged two other cells in the side purge cascade in X-326. USEC hypothesize that the fire resulted when an aluminum component of the process equipment became so hot that it initiated an aluminum/uranium hexafluoride reaction, which is highly exothermic. USEC decided to repair only the two less damaged cells.

Of the 320,187 MTU of UF6 fed to the Portsmouth cascade, 1098.3 MTU contained reprocessed uranium (reactor tails), according to a study conducted for DOE on behalf of Bechtel Jacobs [BJ 00]. The sources included Paducah, Oak Ridge, the Division of International Affairs, Babcock and Wilcox, the US Atomic Energy Commission Office of Safeguards and Materials Management, France, and Portsmouth’s own Oxide Conversion Facility.

The first batch of reprocessed uranium was fed to the cascade during plant startup--527 MTU that had been converted into UF6 at Oak Ridge and Paducah from reactor tails entered the cascade between May and September 1955. The last batch, 1.4 MTU, entered in FY 1997-FY 1998.

This last batch was part of the 14 MTU of HEU downblended in X-126 as the result of the 1994 arrangement between DOE and USEC. Between FY 1968 and FY 1978, small amounts of various assays of reprocessed uranium had arrived at Portsmouth as part of a government scrap return program. They came as UF6 or were converted to UF6 at Portsmouth. The 1.4 MTU downblended in 1997-1998 had come from France (1.1 tons at 56-82% uranium 235) and NUMEC (0.33 tons at 80% uranium 235) in the seventies [BJ 00].

In normal operations the cascade releases a variety of contaminants to the air, prominent among which are uranium, fluorine/fluorides, and Freon coolant. A 1987 DOE report lists the following contaminants as released through the top and side purge cascades in X-326: uranium, technetium, hydrogen fluoride, fluorine, chlorine, sulfur dioxide, SO2F2, Freon 114, ClF3, and CF4. Uranium and technetium are named as the releases from the cold recovery and wet air evacuation systems in X-330 and X-333 [DOE 87].

The exact quantities of uranium and fluorine released from the cascade over the years will never be known, because of the lack of air sampling in the early years. Furthermore, the design of the Portsmouth plant facilitates accidental or intentional venting through unauthorized and/or unmonitored outlets. "The vast piping and valving flexibility associated with the cascade buildings offers many configuration possibilities, including relatively simple means of rerouting both uranium and fluorine release paths to alternative locations, such as those that may not be monitored" [DOE 00a].

Fluorine has been a major problem. "Due to Plant design characteristics, fluorine and fluoride compounds were used in significant quantities and were required to be vented directly as waste gases." An estimated 20 to 30 tons of fluorides are released annually at the plant as a result of routine operations [DOE 00a].

Freon 114, a gas that contributes to the destruction of the ozone layer, escapes from pipe joints, sight glasses, condensers, coolers, and valves. USEC has reported in filings with the Securities and Exchange Commission that Paducah and Portsmouth together lose approximately 750,000 lbs a year. As of 1993, X-333 alone vented approximately 112,390 lbs/yr of Freon to the atmosphere. (In 1993, X-330 contained 1,500,000 lbs of the chemical) [DOE 93].

As for the transuranics and fission products, Bechtel Jacobs estimates that 0.3 g of plutonium were received at Portsmouth of which 0.003 g entered the process equipment; that 140 g of neptunium were received of which 46 g entered the process equipment, and that 60 to 90 kg of technetium 99 "were processed." [BJ 00] The report hypothesizes that any plutonium would have lodged near the feed point; and that neptunium would have lodged on barrier and unplated surfaces near the feed point and remained there until equipment change-out.

Technetium 99, on the other hand, was sorbed on metallic surfaces in the cascade, but, once the entire cascade above the feed point reached equilibrium, would migrate to the top of the cascade. Operators installed magnesium fluoride (MgF2) sidestream traps in four cells in X-126 [BJ 00] and also used portable MgF2 traps to try to absorb "bubbles" of technetium that advanced through the plant, but were only partially successful [DOE 87].

Technetium left the cascade through venting to the atmosphere, in the product stream, and through change-out of equipment. Nevertheless, the cascade is to this day contaminated with technetium. During the 1998 fire in X-276, "The chemical traps on the process vents became saturated and technetium was emitted to the atmosphere." A Lockheed Martin memo of January 6, 1999, states that an estimated 16.6 pounds of UF6 were released at that time.

Alumina and sodium fluoride (NaF) traps used to prevent UF6 from escaping into the atmosphere are a major form of solid waste. The sodium fluoride pellets and alumina were leached in X-705 to recover the uranium that they contained, if the amount of uranium was thought to make recovery worthwhile from an economic standpoint. The depleted/leached traps were buried in the X-749 Contaminated Materials Disposal Facility [DOE 77].

The quantities of trapping material were not negligible. As of 1993, the X-330 cold recovery system generated approximately 1000 lbs of spent uranium-contaminated NaF and 1200 lbs of alumina per year [DOE 93]. As of 1977, an estimated 700 lbs. of contaminated alumina was removed each year from the side and top purge traps in X-326. At that time approximately 75% of the highly enriched UF6 was recovered for return to the cascade before burial of the residue [DOE 77].

The MgF2 traps presented and still present a major problem, because technetium 99 has a half life of more than two hundred thousand years. Some leaching may have been carried out in X-705. A quantity of MgF2 remains on site, but the stream has not been quantified, we are told [BJ 00].

Very large gaskets in the process building ventilation systems were treated with PCBs. As a result the gaskets dripped oil that "signficantly exceed[ed]" the regulatory limit for PcBs of 50 ppm. [DOE 00a] The gaskets also contained uranium. The absorbent material used for cleaning the drips was mixed with floor sweepings and sent to the landfills.

The depleted UF6 that is a byproduct of enrichment is often considered to be a waste, although it usually still contains sufficient uranium 235 to make its enrichment financially profitable under certain circumstances. DOE stores approximately 161,500 tons of depleted UF6 at Portsmouth’s X-745 yards. DOE plans to convert the UF6 to a stable solid.

Coordinates cascade operations, which are controlled primarily in the three process buildings. Responsible for the initial response to plant emergencies. The dome-shaped building is east of the X-326 Process Building. It is constructed of reinforced concrete and designed to resist blasts and shocks [DOE 77]

The facility is used to feed, vaporize, and sample UF6 (uranium hexafluoride) and to generate and purify fluorine. Originally X-342 fed the cascade [BJ 00]. The primary current role of X-342 is generating fluorine, which it does for the entire plant Hydrogen fluoride (HF) is converted to fluorine by an electrolytic process. X-342 now serves as a backup to X-343 and X-344 for the feed, vaporization, and sampling of UF6.

Vaporizes UF6 for feeding to the cascade. The UF6 is received in solid form. X-343 is located approximately 200 ft to the east of X-333 and is connected to the X-333 feed header system. The facility can also sample UF6.

(The Feed Plant was located for the most part in what are now the X-342A Feed Vaporization and Fluorine Generation Building and the X-344A UF6 Sampling Facility [BJ 00]. Other buildings with the name X-344 followed by the letters B, C, E, F, or G performed various auxiliary activities.)

X-344 converted uranium tetrafluoride (UF4) to uranium hexafluoride (UF6).

The plant included four fluorination towers, two cleanup reactor towers for scavenging excess fluorine gas, compressors and cold traps to collect the UF6, and cylinder fill stations.

The UF4 fed into the plant came from Mallinckrodt Chemical Works (MCW) and National Lead of Ohio (NLO) now known as the Fernald Feed Materials Production Center. According to plant records, none of the UF4 contained reprocessed uranium [BJ 00].

However, from August 1958 until October 1961 purge gas from the cascades was processed in the Feed Manufacturing Plant’s cleanup reactor towers to recover excess fluorine. Therefore the plant may have received technetium from the cascades. In fact, a sharp increase in the plugging of filters at the plant after the introduction of the gas from the cascades would seem to indicate that technetium had indeed come with that gas. Furthermore, the plant could have received some transuranics along with the uranium recovered in X-705 from plant effluents and returned to the plant [DOE 00].

UF4 was fed at an average rate of 9.5 MTU per day. The facility produced a total of 11,890 MTU of UF6 [BJ 00].

Ash fell into receptacles that were taken to a storage area. Radiation near the ash receivers was high, as uranium daughter products tended to concentrate in them [DOE 00a]. The radioactivity in the ashes was allowed to decay for two to six months. Then the ashes were blended with the incoming UF4 and refluorinated in the towers. When the installation closed in 1962, the ashes that remained were sent to Paducah for uranium recovery.

Liquids from decontamination of filters and from maintenance were sent to X-705 for recovery of the uranium. The recovered uranium was returned to X-344, blended with the incoming UF4, and fed into the fluorination towers.

In the plant, leaks and spills of UF4 and ash "presented continuing problems with surface and airborne contamination." The Feed Plant was a major contributor to uranium releases, as it lost an average of 407 kg of uranium (0.22 Ci) per year to the atmosphere from 1959 to 1962. Releases from Portsmouth as a whole dropped sharply in 1963 after the shutdown of the plant [DOE 00a].

Waste acid from a water scrubbing system for gaseous effluents was neutralized with lime and then released to the sewer.

The building originally housed the process equipment, offices, and maintenance areas for the X-344 Feed Manufacturing Plant (see above). The building was abandoned in 1962 after feed production ceased. In the early 1970s work on converting the building began, but during construction a fire caused the explosion of a propane tank. The explosion "destroyed much of the immediate area" and caused a portion of the second floor to cave in. Work was resumed after two years and completed in 1975. The building housed the High Assay Sampling Area (HASA) for a time. The former HASA is now a storage area.

X-344A currently handles the sampling and the transfer of UF6 from one cylinder to another. Toll product is withdrawn from the cascade into 10-ton DOE cylinders and then transferred here to 2.5 ton commercial shipping cylinders.

North and South vaults store or stored highly enriched uranium. The central area houses a high-assay sampling area (HASA) and a small laboratory. The area around the HASA is known to be contaminated. "The available documentation designates the entire building as having fixed radiological contamination," although the custodian told DOE that the contamination is localized [DOE 93]. DOE describes the sampling facility as a source of fluoride and uranium emissions [DOE 00a]

X-626-1 and X-626-3 circulate and recirculate water that is used to remove the heat of compression from the process gas, along with waste heat from a few auxiliary processes, and to dissipate this energy to the environment. They, like systems connected with the X-330 and X-333 process buildings function as an independent unit for the most part, but they belong to an overall plant-wide recirculating cooling water system (RCW). (See below for the X-330 and X-333 facilities

Each process building’s cooling system consists of a primary loop, which comes into contact with the hot UF6, and a secondary loop, which receives the heat through a heat exchanger and carries it to the cooling towers. In the cooling towers, the heated water in the secondary loop comes into contact with cool atmospheric air, which absorbs the heat. The heated air is discharged at the top of the tower and the cooling water falls through the tower, is collected in a basin below the tower and then recirculated.

To limit the amount of concentration of solids that will occur in the recirculating water, a quantity of water called blowdown is removed from the system continuously to remove dissolved solids. Blowdown water is routed from the X-626 system through the X-630 system to the X-633 system and thence to the X-616 treatment facility [DOE 77].

The recirculating water system discharges water vapor and some particulate matter, which is a product of the drift emissions. Solids in cooling tower drift as of 1977 were chromium, zinc, copper, iron, chloride, sulfate, silica, and sodium pentachlorophenate [DOE 77]. Sodium pentachlorophenate is a fungicide that, before 1982, was used to treat the wood of the cooling tower. After 1982 cupric arsenate was applied to the wood. An unknown quantity of the fungicides may leach into the cooling water, a 1993 report states Freon 114 (a coolant) and freon 113 (a solvent) had been detected in cooling water prior to 1993 and was reported as a potential contaminant. The Freon compounds apparently entered from the process building coolant systems at a minimum rate of 60,000 pounds per year [DOE 93].

Until June 1989 the plant added to the cooling water a hexavalent chromium-based composition to inhibit corrosion. This material was replaced at that time with a phosphate-based formula, but chromium lingered for a period in the recirculating water. "In 1991 it was reported, using best engineering judgment, that 860 lbs of chromium and 140,000 lbs of chlorine (in the form of HOCl) were released into the air via stacks [DOE 93]. (According to DOE’s Investigative Report, the RCW treatment system was switched to a phosphate-based inhibitor in 1991, not 1989 [DOE 00b]).

In 1991, 710 lbs of chromium were estimated to have been released into the Scioto River [DOE 93]

(see X-626 above on the cooling water system)

(see X-626 above on the cooling water system)

The building is used for equipment maintenance support for non-radioactive or low-level radioactively contaminated equipment from the diffusion cascade. It houses Chemical Cleaning and Operations, the Converter/Weld Shop, and the Radiation Calibration Lab. The Chemical Cleaning and Operations has been modified as needs have changed. It included a stabilization area or furnace stand, where workers pretreated converters with heated fluorine gas before installing them in the cascade. Fluorine gas was piped into the building for this purpose. Chemical Cleaning also had two vapor degreasers, both of which began operation in 1955. One was shut down around 1975 and removed in the early 1980s. The other was shut down in 1988, but in 1993 was still present [DOE 1993]. Heated TCE was used for degreasing until 1987; 1,1,1,-trichloroethane has been used since [DOE 00b].

The degreasers generated about 500 to 1000 gallons monthly of air emissions of evaporated TCE or TCA [1993, 275].

In the stabilization area, the fluorine gas, after use, "was vented, directly into the air 8 to 10 ft above the ground, along with heat emissions" [1993, 275].

TCE that entered floor drains went, via a sump, to the X-701C pit, from which it was sent to the X-701B holding pond. X-700 was the major source of TCE in X-701B and in the entire east drainage ditch area [DOE 70].

As of 1993 the building housed five operations: process equipment disassembly and decontamination, small parts cleaning and decontamination, recovery of uranium from decontamination solutions, routine chemical analyses, and laundry of company clothing worn by plant personnel (we describe below only the first two of these five operations). From 1957-1978 the conversion into uranium hexafluoride of uranium recovered from the decontamination solutions and of other uranium materials also took place in the building.

Workers disassembled large parts of cascade equipment, vacuumed them to remove uranium compounds, and treated them in a "decontamination tunnel, "a series of five spray booths. The first three booths contained recirculating nitric acid, ammonium carbonate, and rinse water [DOE 77] or nitric acid, citric acid, or acetic acid solutions [DOE 00a]; the fourth used nonrecirculating rinse water, and the fifth was a drying chamber.

Workers disassembled and decontaminated compressor seals and other small parts by hand in the "seal disassembly room." They used recirculating water, nitric acid, and ammonium carbonate solutions at four hand tables. The parts, after being treated at the hand tables, went to a "steam pit" with steam guns and small containers of nitric acid, alkali, and isopropyl alcohol for removal of the "last traces" of uranium [DOE 77].

Empty feed/product cylinders were cleaned to decontaminate them and remove heels (nonvolatile materials that remain in cylinders after the UF6 that they contain is vaporized by heating). If the UF6 was made from reprocessed uranium, they contain transuranics, fission products, and irradiating daughters of uranium 232. In the 1950s and 1960s, cylinders were hosed down in an open area, where wash water spilled onto the floor. After November 1970 a closed "cylinder decontamination facility" was installed. Cylinders were placed in a turning fixture and connected to piping through which boric acid and sodium carbonate cleaning solutions and rinse water were recirculated. The cylinders were then heated in an enclosed drying booth [DOE 00a]

Acid solutions from the spray booths and seal disassembly room, and cleaning and rinse solutions from the cylinder decontamination facility were sent to the Uranium Recovery Facilities [DOE 00a].

As of 1993 wastewater from the decontamination operations was treated in X-705 before discharge to the sanitary sewer and then further treated in the X-6619 Sewage treatment Plant before discharge to the Scioto River. The treatment systems were designed to dentrify and to remove heavy metals. However, monitoring at the outfall for X-705 detected in 1991 copper, iron, nickel, and zinc at maximum levels of 499 picog/l, 7890 picog/l, 728 picog/l, and 1040 picog/l respectively.

Also, as of 1993 the building’s sump water contained a high level of TCE, which may have been coming from groundwater. The sump water was pumped and trucked to the X-622 Carbon Filtration Facility for treatment [DOE 93].

Area B of the X-705 building recovered uranium from a variety of liquid solutions and solid waste materials

The basic facility used a solvent extraction process, which involved dissolving uranium oxides in nitric acid, removing any insoluble solids, evaporating the liquid to reduce its volume, separating uranium from contaminants by solvent extraction pulse columns, drying the uranyl nitrate solution in a drum dryer, and passing the resulting material through a calciner and rolling mill to produce dry triuranium octoxide (U3O8) [DOE 00a].

For UNH, the treatment differed. Crystals of UNH were dissolved in water. The solution was fed to a rotary calciner, where the water evaporated and the UNH melted. Denitration took place, and the UNH became UO3. The UO3 moved down the calciner into a hotter zone, where it was reduced to U3O8 [DOE 77]. UNH produced by reprocessing in a foreign country or countries was converted to oxide in the calciner during at least 1965, 1966, 1975, and 1976 [DOE 00a].

Waste from the recovery process is mainly the depleted acid (raffinate) from the extraction column. Starting in 1975, technjnetium and transuranic contaminants were identified in liquid process effluents from X-705. Transuranics stayed with the uranium for the most part, but technetium 99 entered the raffinate stream. The raffinate stream also contained uranium daughter products. This stream was "initially discharged to an onsite ditch that flowed to Little Beaver and Big Beaver Creeks, and then to the Scioto River." Subsequently the raffinate was directed to an onsite settling pond, X-701B [DOE 00a]. During 1984, the discharge to X-701B was permanently suspended with the startup of the heavy metals precipitation process (X-705), technetium 99 ion exchange process (X-705), and biodentrification process (X-700) [BJ 00].

The calciners released nitrogen oxides to the building roof vent. As of 1977 a total of approximately 5600 pounds of nitrogen oxides were emitted annually from calciners in the B and F areas of X-705 [DOE 77].

(According to a source published in 2005, the Oxide Conversion Facility was located in the E, F, and H areas of X-705 [BJ 00a]. A September 1977 EIS on a possible plant expansion, which includes a diagram of X-705, placed it in Section C. Possibly the sections have been renamed. According to DOE’s May 2000 investigative report, the oxide conversion areas were "physically separated" from the decontamination and recovery areas described above [DOE 00a]).

Oxide conversion used a one-step process to convert oxides of uranium into uranium hexafluoride by direct fluorination .

The original system was composed of three stirred-bed reactors. In 1959 these reactors were replaced by a four-inch-diameter open flame tower, with a nominal capacity of 7200 kgU/yr output as UF6. This system, which involved manual handling of fine uranium oxide powder, was dismantled and removed. A new system, with more automated processes and glovebox enclosures and with a nominal capacity of 20,000 kgU/yr output as UF6, was installed in 1967 in preparation for the processing of oxides from irradiated fuel. It centered in an improved five-inch flame tower.

U308 was ground and fed through the top of an air-cooled flame tower into an elemental fluorine atmosphere, where there was a spontaneous flame reaction between the oxide and the fluorine, which produced UF6 and oxygen. The UF6 was passed through a sintered metal filter to remove particulates and then through a MgF2 trap for sorption of certain impurities [BJ 00]. It was then withdrawn into cold traps where it solidified. Cold traps were removed and heated to liquify the UF6. The liquified UF6 was drained into cylinders for feeding to the cascade.

The oxide that did not react during the first pass through the tower was collected in an ash pot at the bottom of the tower and subsequently pulverized and refed to the tower. Most of the impurities in the oxide were filtered from the gas stream in a secondary disengagement section. The "filter ash," which was less than 1% uranium, was processed through the Uranium Recovery Facilities [DOE 77].

In theory any plutonium should concentrate in the tower ash and filter ash, and neptunium in the MgF2. In actuality, the pathways followed by plutonium and neptunium depended on several variables. As much as 85% of the neptunium and 57% of the plutonium may have ended up in UF6 product cylinders. The filter ash would contain the majority of the remainder of the transuranics [BJ 00].

The conversion facility received uranium from at least 47 sources [BJ 00]. Raw material was produced in X-705’s Uranium Recovery Facilities through uranium recovery operations and through conversion of uranyl nitrate hexahydrate (UNH) from off-site sources. It also came in the form of oxides directly from commercial processors, and from "government sources" [DOE 00a]. It is reported that 5.6 MTU of feed contained transuranics [BJ 00]. According to a memorandum of September 20, 1978, the facility handled highly enriched uranium, at least during a July 1978 "test run, utilizing 97% material," which resulted in a "number of unexplained high airborne samples."

Production

The facility produced about 233 MTU of UF6 [BJ 00].

An unknown quantity of filter ash went through Uranium Recovery to create U3O8 for a second attempt at conversion to UF6. "The filter ash that remains on-site is stored in the X-326 "L" Cage.

Some of the magnesium fluoride may have been treated in Uranium Recovery. An unknown quantity, some of which may have come from the Oxide Conversion Facility, remains on site.

The sodium fluoride was regenerated through in-place heating, and also treated in Uranium Recovery to leach out the uranium. Depleted/leached media was placed in cans, the cans packed in wooden boxes in which lime filled the spaces, and the boxes buried in the X-749A landfill [BJ 00].

"Very high airborne concentrations of radioactive material were prevalent in the oxide conversion facility" and "could have been vented to the atmosphere through penetrations, ventilation systems, doors, and windows." According to a 1977 report, an unfiltered exhaust system vented air through a roof stack [DOE 00a].

The annex was created for the disassembly and decontamination of large pieces of equipment from the cascades that were contaminated with high levels of technetium. Operations also included regeneration of alumina traps.

According to the DOE 2000 investigative report, the area had the "highest average airborne contamination in the X-705 complex." Air was released "through absolute filters to reduce airborne emissions to the environment" [DOE 00a].

Building X-710 houses laboratories and facilities that provide technical support and development activity to the plant. Because development of processes and procedures for the plant has been an integral part of the facility’s mission for most of its life, "a myriad of experiments" that involved transuranics and fission products have been carried out there. They involved "minor/trace amounts of these elements/isotopes" [BJ 00].

Initially the building was a pipe fabrication facility, where operations included degreasing the interior surfaces of pipes with organic solvents. Later, but still in the early years, it served as the non-UF6 and small cylinder UF6 storage area. Overflow materials from X-705 were also stored here. The DOE investigative report stated that X-744G was "used for several years to store spent chemical trap materials, miscellaneous dried sludges, and ash from the X-705 incinerator," which included RCRA wastes [DOE 00a].

When, around 1996, the scrap return program was initiated, the building was designated as the scrap storage warehouse and central receiving facility. Thus it received oxides, UNH, and small cylinders of UF6. Non-UF6 containers were opened and sampled. All oxides were stored in the building until, around 1978 when, with the opening of X-345, HEU materials went to that facility.

In recent years the building was renovated to store uranium in quantity. The Draft Environmental Impact Statement on the dispatch of surplus Hanford site uranium to Portsmouth states "Building 744-G, the primary receipt facility under consideration, has been upgraded . . . The facility, termed the Uranium Management Center, is expected to house a total of approximately 5900 MTU (13,000,000 pounds) of uranium materials" [DOE 99b].

In August and September 1999 X-744G received shipments of uranium materials from the Universities of Seattle and Nebraska respectively. The January 2000 issue of the Portsmouth Environmental Bulletin describes the shipments as totaling 20 MTU that DOE had previously loaned to these two universities for purposes of research and education. However, the September 2000 issue of that publication states that Portsmouth is receiving about 20 MTU that DOE lent to "various universities around the country," and DOE announced at a public meeting January 27, 2000, that Portsmouth had received in 1999 for storage 2.2 MTU of aluminum-clad metal slugs with uranium enriched to 0.947% from the University of Seattle and 2.5 MTU of aluminum-clad metal slugs with "normal" uranium from the University of Nebraska.

In 2000, Fernald is in the process of shipping 3800 MT of depleted and natural uraniium to Portsmouth for storage. Shipments should be complete by late 2001. The uranium is being sent to X744-G "for interim storage."

In June 2000, DOE issued a Finding of No Significant Impact on plans to ship to Portsmouth from DOE’s Hanford site, for storage, approximately 900 MTU composed of uranium metal billets (235 MTU), low-enriched uranium trioxide powder (approximately 670 MTU), and uranium dioxide and depleted uranium in various forms (approximately 4 MTU). This uranium is "readily saleable," DOE claims [DOE 00b].

The "Recycled Uranium Mass Balance Report" describes X-744G as currently "support[ing] the DOE PORTS Uranium Management Center activities. Quantities of materials containing TRU are being stored here as part of this program. These materials were received after the March 1999 timeframe" for the report [BJ 00]. Of the materials at X-744G known to the public, those from the Universities of Seattle and Nebraska would seem to be the most likely to contain transuranics.

While serving as a storage center, the facility has also in the past been the center for other activities. A smelter for scrap aluminum, primarily parts of compressors, was located here from 1961 through 1983.

Material went through a decontamination process before being melted, but the unit experienced problems with "airborne contamination." Uranium contamination in the feed tended to stay with the melted aluminum. Nevertheless, "aluminum ingots were sold for unrestricted use" as well as used for replacement parts for cascade equipment [DOE 00a].

X-744G was a source of radionuclide and fluorine releases [DOE 00a], perhaps in connection with the smelting of aluminum.

DOE investigators heard from people they interviewed in 1999/2000 that "a massive release" occurred in X-746. It is used in 2000 for personnel and administrative functions [DOE 00a]. The 1993 audit describes the building as a "Shipping and Receiving Building" [DOE 93].

The building’s mission was pilot-scale development work on new chemical processes prior to or in aid of plant development. "Early development projects, including decontamination process experiments, boiling freon heat exchanger experiments, UF6 heating studies, uranium oxide pelletizing experiments, freon drying tests, and controlled UF6 releases in a sealed environmental chamber, were conducted in this facility." Here also was done development work on the "fluorox process," which appears to have involved a prototype fluorination tower for the Feed Manufacturing or Oxide Conversion Facility. According to records X-760 received, from K-25 in 1957, 0.86 MTU of UF4, 0.4 MTU of UO2, and 3.3 MTU of UO3 classified as recycled uranium. Likely, any materials converted to UF6 in X-760 were fed to the cascade, and materials not converted there were converted to UF6 in X-705 when it began to operate. [BJ 00].

Construction of a gas centrifuge enrichment plant began at Portsmouth in 1979. It was halted, before the plant was completely built, in 1985. The GCEP installation consists of numerous facilities, including a Switch House, Switch Yard, and Centrifuge Training Facility. Only four are mentioned here.

According to Inside Energy (December 7, 1987), DOE in 1987 sold 1300 unused centrifuges to a Tennessee company, AlChemIE, which was to use them to enrich non-uranium stable isotopes. X-3001 and X-3002 are reportedly today basically empty buildings.

DOE announced October 6, 2000, that it will again develop centrifuge enrichment capability. Initial work will take place at Oak Ridge, but within a year the focus will shift to Piketon. Existing facilities will be refurbished to house a demonstration project.

This building was converted into an approved mixed waste storage facility in 1992. It has five floors with a total of 20 acres of floor space. A RCRA Part B storage permit was issued by Ohio Environmental Protection Agency in August 1995. At the present time the facility stores all plant mixed and hazardous waste, except that stored for security reasons in X-326 L Cage. [DOE 00a] It also stores low-level radioactive waste and Toxic Substances Control Act waste. This building also provides office space.

At least eight (A-H) cylinder storage yards exist or have existed at Portsmouth. All DOE-managed cylinders with depleted uranium hexafluoride (cylinders containing depleted UF6 produced before DOE leased enrichment facilities to USEC) are stored in cylinder yards X-745-C (C yard) and X-745-E (E yard). These yards store a total of 13,388 cylinders. The cylinders in Yards C and E contain approximately 161,500 tons of depleted UF6.

As of 1998, another yard, X-745-G, stored 2800 United States Enrichment Corporation (USEC)-generated cylinders. The X-745-G yard is just outside the perimeter road that defines what is known as the Portsmouth Uranium Enrichment complex.

The heels of cylinders that contained reprocessed uranium and were not subsequently decontaminated/washed would contain transuranics, fission products, and the daughters of uranium 232 (bismuth 212 and thallium 208, emitters of hard and intense gamma radiation). It is possible that some cylinders were emptied and refilled several times without washing, which would have concentrated the contaminants.

Several small diameter UF6 cylinders containing highly-enriched reprocessed uranium were received from offsite sources in the seventies. Most of this HEU was only fed to the cascade around 1997. The cylinders were then cleaned in X-705 or at Nuclear Fuel Services. The solution from the cleaning at X-705 is stored, in blended down form, in X-705, because of operational problems at that facility. What happened to the cylinders sent to Nuclear Fuel Services and their solutions is not known [BJ 00].

The yard stores over 7 million pounds (32,700 cubic meters) of scrap materials. It occupies approximately 6.8 acres and, as of 1993, was surrounded by a chain-link, barbed-wire fence. The stored material includes large metal cascade scrap that has gone through a decontamination process in X-705/X-700 [DOE 93]. "The vast majority of the material is contaminated and has been in storage since the 1970s," DOE said in its recent investigative report. In early 2000, plans were being made to sort, repackage, and ship a portion of the scrap metal [DOE 00a].

At Portsmouth waste oils were treated according to a process developed in Oak Ridge. However, the fertilizing and tilling or disking that the process required were not adequately implemented. "Approximately 24,500 gallons of waste oil contaminated with solvent and radionuclides, 124,300 pounds of oil-soaked fuller’s earth, 60 gallons of TCE, and 1,000 gallons of chlorinated solvents were applied at the X-231A oil biodegradation plot." The area was temporarily capped in 1987 as part of an interim remedial measure [DOE 00a].

The site consists of two disposal plots, each surrounded by an elevated soil berm. It was used for "land application" [Port 99c] of uranium-contaminated waste oil, PCBs, and solvents [DOE 00a]. No records were kept of the quantity of solvents applied [DOE 00a] After use ceased, the site was treated "to remove volatile organic compound contamination present in the soil" [Port 99c]. The site was temporarily capped in 1987 as part of an interim remedial measure [DOE 00a].

The facility was constructed to treat cooling water blowdown in order to meet the permitting process put into place by the 1970 Clean Water Act [DOE 68]. It reduced hexavalent chromium to trivalent chromium by adding sulfur dioxide to the water. The treatment resulted in the precipitation of chromium hydroxide sludge. Treatment was suspended in 1990 after the chromium-based inhibitor had left the system. X-616 also treated effluent from the X-700 Chemical Cleaning facility and the X-705 Decontamination Building [DOE 93].

The chromium hydroxide sludge formed as a result of treating hexavalent chromium was stored in two surface impoundments to the west of the facility. Closure of the impoundments began in 1990. At that time the sludge was removed, treated, and placed in the X-735 landfill [DOE 93]. In 2000, the sludge, more than six million pounds in total, is being shipped to Envirocare in Utah for disposal, according to the Portsmouth Environmental Bulletin, Sept. 2000.

Treated water was piped to the Scioto River [DOE 00a]. According to 1991 monitoring data, the maximum concentrations of hexavalent chromium and total chromium were 20 micrograms/liter and 1560 micrograms/liter respectively [DOE 93].

Received contents of the sump that was in the X-700 Chemical Cleaning Facility, which was contaminated with TCE. The waste then went to the X-701B holding pond. The pit was closed in 1988 [DOE 00a]

This unlined pond was "used for the neutralization and settling of metal-bearing waste water, solvent-contaminated solutions, and acidic waste water." Most of the waste came from the X-700 Chemical Cleaning Facility and the X-705 Decontamination Building [DOE 00a]. As a result of the decontamination of material that had been in contact with reprocessed uranium, an estimated 1415 grams of technetium were sent in the raffinate to the holding pond. Furthermore, 0.03 grams of plutonium and 3.3 grams of neptunium were measured in the X-701B sludge when it was characterized for low-level waste disposal [BJ 00].

In 1972 facilities to feed slaked lime and photoelectrolyte to neutralize the low pH and promote the precipitation of uranium along with transuranics and technetium, were added. Once or twice a year, the pond was dredged or sludge pumped to containment ponds next to the settling pond.

During 1984 the discharge of raffinate to X-701B was permanently suspended due to the startup of treatment processes in X-705 and X-700. X-701B and the two containment ponds have been dredged and their contents and the first foot of soil beneath them packaged. Portsmouth has shipped the sludge to the Envirocare disposal facility in Utah.

The pond was a major effluent source to Little Beaver Creek [DOE 00a].

During construction of the plant, an area south of the main buildings was used for the disposal of construction waste. Named after the construction contractor, the area became the site’s landfill after initial construction was completed. [DOE 00a]

As an interim remedial measure to take care of surface seeps, adjacent Big Run Creek was rerouted, and a seep collection/treatment system installed in the original creek bed. A cap was installed on the landfill in 1998 [DOE 99c].

The southern portion of the landfill contains asbestos, floor sweepings,, sanitary waste, and sewage plant coarse screenings. The northern portion contains these materials and rags used to remove solvents in the X-720 paint shop. Because of the rags, the northern part of the landfill had to be closed according to RCRA hazardous waste facility closure regulations. The southern part was closed according to State of Ohio solid waste regulations [DOE 00a]. Closure was completed in 1998 [DOE 99c].

The landfill received "alumina-trap residue, sodium fluoride, incinerator ash with trace quantities of neptunium and plutonium," among other materials. [DOE 00a] Disposal volumes throughout the 60s and early 70s were in the hundreds of cubic feet a year. A 1976 report on waste disposal, stated that "much of the chemical trap material contained technetium-99, which is highly water soluble." Following the report, the chemical trap material was placed in sealed packages before disposal, but it had been buried without packaging for almost twenty years.

Between August 1984 and June 1985, approximately 85,000 pounds of metal hydroxide sludge from the X-705 raffinate was buried at this facility, although the sludge could leach cadmium. The State of Ohio EPA directed that the landfill be closed, because of the inappropriate burial of such RCRA waste. It closed in 1990 [DOE 00a ]. Closure included the installation of a multimedia cap, a slurry wall, and subsurface groundwater drains [Port 99c].

This site was operated for the disposal of wastes classified under the Atomic Energy Act and was intended to meet the needs of Portsmouth "and other DOE and non-DOE facilities" [DOE 00s]. All materials placed at the site were directly connected with the gaseous diffusion process, except for two boxes of specimens from Bettis Atomic Power Laboratory (metal shapes clad with zirconium, zirconium alloy, or hafnium) [DOE 58]. The waste buried at the site included a dismantled INCO (International Nickel Company) Nickel Plant from Huntington, West Virginia. The INCO plant was contaminated with nickel carbonyl and uranium. (The plant had produced nickel in support of DOE’s three enrichment plants.) [DOE 00a] The site also includes classified records, compressor blades and other classified parts.

The facility was closed in 1994 with the construction of a multilayer cap and a drainage system to capture surface water runoff. [Port 99c]

Unsampled hydrocarbon-contaminated oils were burned in at least "three 18-inch diameter salamander oil burners" on the west side of X-705. DOE describes these devices as "trays, salamanders (a primitive device consisting of an upright tube mounted on a base)."

A 1973 Oak Ridge health protection appraisal found that "smoke from the salamanders (believed to contain phosgene gas) was introduced into the ventilation system [at X-705] and released into the X-705 high bay."

A former employee indicated to DOE investigators that PCBs were burned in the Salamanders. "The area where burning and spreading occurred was covered with 10-12 inches of concrete. The spreading of polychlorinated biphenyl (PCB) oil was then moved to area south of X-326" [DOE 00a].

Beginning in the 1950s, two oil-fired incinerators burned waste: one, "security burnables" and the other "uranium-contaminated wastes generated from Plant operations." Former employees told DOE that the latter burned solid and liquid wastes and "routinely produced heavy black smoke." The two were replaced in 1971 by a "pre-engineered" dual chamber incinerator installed in the location of the uranium-contaminated waste incinerator, south of X-705. The new incinerator, called by employees the "Radicator," burned materials from some one hundred locations at the plant [DOE 00a].

Incinerator ash was sampled. If the ash contained sufficient uranium for the uranium to be worth recovering, it was sent to the X-705 uranium recovery facility. If not, it was usually boxed and placed in the X-749 landfill as long as it operated. Ash from the burning of floor sweepings collected in areas where classified components were managed, was sent to the X-749A classified landfill. [DOE 00a].

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*The Uranium Enrichment Project is a project of Earth Island Institute’s Yggdrasil Institute.

BJ (Bechtel Jacobs Company), 2000, "Recycled Uranium Mass Balance Project, Portsmouth, Ohio, Site Report," BJC/PORTS-139/R1, Prepared by TetraTech NUS and Theta Technologies, Inc. under subcontract 23900-BA-ES008 for the US Department of Energy, Office of Environmental Management, June 19.

DOE (US Department of Energy), 1987, "Environment, Safety, and Health Office of Environmental Audit, Environmental Survey Preliminary Report, Portsmouth Uranium Enrichment Complex," Piketon, Ohio, August.

DOE (US Department of Energy), 1993a, "Report for Environmental Audit Supporting Transition of the Gaseous Diffusion Plants to the United States Enrichment Corporation," DOE/OR/10807&V2, Appendix A, Volume I: Portsmouth Site Reports, June.

DOE (US Department of Energy), 1993b, "Report for Environmental Audit Supporting Transition of the Gaseous Diffusion Plants to the United States Enrichment Corporation," DOE/OR/1087&V3, Appendix A, Volume II: Portsmouth Facilities Reports, June.

DOE (US Department of Energy), 1999a, "Programmatic Environmental Impact Statement for Alternative Strategies for the Long-Term Management and Use of Depleted Uranium Hexafluoride," DOE/EIS-0269, Office of Nuclear Energy, Science and Technology, Germantown, Maryland, April.

DOE (US Department of Energy), 1999b, "Draft Environmental Assessment: Disposition of Surplus Hanford Site Uranium, Hanford Site, Richland, Washington," DOE/EA-1319, Richland Operations Office, Richland, Washington, November.

DOE (US Department of Energy), 1999c, "Portsmouth Annual Environmental Report for 1998," DOE/OR/11-3031, 2 volumes, Prepared by EQ Midwest, Inc. under subcontract 23900-SC-SM002F for the US Department of Energy, December.

DOE (US Department of Energy), 2000a, "Independent Investigation of the Portsmouth Gaseous Diffusion Plant," 2 volumes, Office of Oversight, Environment, Safety and Health, May.

DOE (US Department of Energy), 2000b, "Environmental Assessment: Disposition of Surplus Hanford Site Uranium, Hanford Site, Richland, Washington," DOE/EA-1319, Richland Operations Office, Richland, Washington, June.

ERDA (Energy Research and Development Administration), 1977, "Final Environmental Statement, Portsmouth Gaseous Diffusion Plant Expansion, Piketon, Ohio," ERDA 1549, Vol. 2 of 2, September.

NRC (US Nuclear Regulatory Commission), 1999, "Compliance Evaluation Report for the renewal of Certificate of compliance GDP-2, Revision 1, United States Enrichment Corporation, Portsmouth Gaseous Diffusion Plant, Piketon, Ohio," Docket 70-7002, January.

X-231A Oil Biodegradation Plot #28

X-231B Oil Biodegradation Plot #29

X-326 Process Building #3

X-300 Central Control Building #4

X-330 Process Building #2

X-333 Process Building #1

X-342 Feed Vaporization and Fluorine Generation #5

X-343 Feed Vaporization and Sampling #6

X-344 Feed Manufacturing Plant #7

X-344A UF6 Sampling Facility #8

X-345 Special Nuclear Materials Storage #9

X-611A Lime Sludge Lagoons #30

X-616 Liquid Effluent Control Facility #31

X-626-1 Recirculating Cooling Water #10

X-630-1 Recirculating Cooling Water #11

X-633-1 Recirculating Cooling Water #12

X-700 Maintenance Building #13

X-701B Holding Pond #33

X-701C Neutralization Pit and Pump Pit #32

X-705 Decontamination and Recovery #14

X-705 Salamanders #39

X-705A/B Incinerators #40

X-710 Technical Services Building #15

X-710B Building #16

X-720 Maintenance and Stores Building, #16a

X-734 Old Sanitary Landfill #35

X-735 Sanitary Landfill #36

X-744G Bulk Storage Warehouse #17

X-745 Cylinder Storage Yards #24

X-746 UF6 Sampling and Shipping Center #18

X-747H Northwest Materials Storage #25

X-749 Contaminated Materials Disposal Facility #37

X-749A Classified Materials Disposal Facility #38

X-749B Peter Kiewit Landfill #34

X-760 Chemical Engineering Building #19

X-3001 Gas Centrifuge Enrichment Plant Process Building #20

X-3002 GCEP Process Building #21

X-3346 GCEP Feed and Withdrawal #22

X-7725 GCEP Recycle/Assembly #23

A Hot Yard #26

Small Hot Yard --#27

                                            copyright © 2000 by Mary Byrd Davis