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Three Mile Island accident

The Three Mile Island accident was a partial meltdown of reactor number 2 of Three Mile Island Nuclear Generating Station in Dauphin County, near Harrisburg, subsequent radiation leak that occurred on March 28, 1979. It was the most significant accident in U. S. commercial nuclear power plant history. On the seven-point International Nuclear Event Scale, the incident was rated a five as an "accident with wider consequences"; the accident began with failures in the non-nuclear secondary system, followed by a stuck-open pilot-operated relief valve in the primary system, which allowed large amounts of nuclear reactor coolant to escape. The mechanical failures were compounded by the initial failure of plant operators to recognize the situation as a loss-of-coolant accident due to inadequate training and human factors, such as human-computer interaction design oversights relating to ambiguous control room indicators in the power plant's user interface. In particular, a hidden indicator light led to an operator manually overriding the automatic emergency cooling system of the reactor because the operator mistakenly believed that there was too much coolant water present in the reactor and causing the steam pressure release.

The accident crystallized anti-nuclear safety concerns among activists and the general public, resulted in new regulations for the nuclear industry. It has been cited as a contributor to the decline of a new reactor construction program, a slowdown, underway in the 1970s; the partial meltdown resulted in the release of radioactive gases and radioactive iodine into the environment. Anti-nuclear movement activists expressed worries about regional health effects from the accident. However, epidemiological studies analyzing the rate of cancer in and around the area since the accident determined there was a small statistically non-significant increase in the rate and thus no causal connection linking the accident with these cancers has been substantiated. Cleanup started in August 1979, ended in December 1993, with a total cleanup cost of about $1 billion. In the night time hours preceding the incident, the TMI-2 reactor was running at 97% power, while the companion TMI-1 reactor was shut down for refueling.

The main chain of events leading to the partial core meltdown at 4:37 am EST on March 28, 1979, began in TMI-2's secondary loop, one of the three main water/steam loops in a pressurized water reactor. The initial cause of the accident happened eleven hours earlier, during an attempt by operators to fix a blockage in one of the eight condensate polishers, the sophisticated filters cleaning the secondary loop water; these filters are designed to stop minerals and impurities in the water from accumulating in the steam generators and increasing corrosion rates in the secondary side. Blockages are common with these resin filters and are fixed but in this case the usual method of forcing the stuck resin out with compressed air did not succeed; the operators decided to blow the compressed air into the water and let the force of the water clear the resin. When they forced the resin out, a small amount of water forced its way past a stuck-open check valve and found its way into an instrument air line.

This would cause the feedwater pumps, condensate booster pumps, condensate pumps to turn off around 4:00 am, which would in turn cause a turbine trip. As the steam generators were no longer receiving feedwater and pressure increased in the reactor coolant system, causing the reactor to perform an emergency shutdown. Within eight seconds, control rods were inserted into the core to halt the nuclear chain reaction; however the reactor continued to generate decay heat, because steam was no longer being used by the turbine, heat was no longer being removed from the reactor's primary water loop. Once the secondary feedwater pumps stopped, three auxiliary pumps activated automatically. However, because the valves had been closed for routine maintenance, the system was unable to pump any water; the closure of these valves was a violation of a key Nuclear Regulatory Commission rule, according to which the reactor must be shut down if all auxiliary feed pumps are closed for maintenance. This was singled out by NRC officials as a key failure.

The loss of heat removal from the primary loop and the failure of the auxiliary system to activate caused the primary loop pressure to increase, triggering the pilot-operated relief valve at the top of the pressurizer – a pressure active-regulator tank – to open automatically. The relief valve should have closed when the excess pressure had been released, electric power to the solenoid of the pilot was automatically cut, but the relief valve stuck open because of a mechanical fault; the open valve permitted coolant water to escape from the primary system, was the principal mechanical cause of the primary coolant system depressurization and partial core disintegration that followed. Critical user interface engineering problems were revealed in the investigation of the reactor control system's user interface. Despite the valve being stuck open, a light on the control panel ostensibly indicated that the valve was closed. In fact the light did not indicate the position of the valve, only the status of the solenoid being powered or not, thus giving false evidence of a closed valve.

As a result, the operators did not diagnose the problem for several hours. The design of the pilot-operated relief valve indicator light was fundamentally flawed; the bulb was connected in parallel with the valve solenoid, thus implying that the pilot-operated relief valve was shut when it went dark, without verifying the real position of the valve. When everything was operating the indication was true and the operators bec

CiriƩ

Cirié is a comune in the Metropolitan City of Turin in the Italian region Piedmont, located about 20 kilometres northwest of Turin. Cirié borders the following municipalities: Nole, San Carlo Canavese, San Maurizio Canavese and Robassomero. Cirié, about 13 miles northwest of Turin, is located at the end of the Lanzo valleys, close to a plateau called "Vauda", a Celtic origin term indicating a forest; the area is close to a creek which flows west northwest of the city. The area around Cirié, since about the third century BC, had a Celtic tribe settlement. Before the Roman rule, according to Polybius, this area was covered in thick forests, with few glades, some small villages and sparse tracks linking the settlements. In 143 BC, the Romans, led by consul Appius Claudius Pulcher, moved against the tribes living Orco and Dora Baltea valleys, to open a way towards Elvetia and Gaul; the Romans thought of a fast victory, but the Celtic tribes fought back with such a strength that the legions had to retreat.

For this reason, the Romans set up several camps, for a better control of adjacent areas. Castra were set up in the current neighbors of Ivrea and Cirié, where the soldiers could control access to the Lanzo valleys; the castrum stativum in the Cirié area was called Castra Cerreti, deriving this name from the turkish oak, an oak tree whose forests were abundant in the neighbors. In years, it became known as Cerretum for short; the cardo maximus, of the ancient castrum coincides with via Vittorio Emanuele II, the current main street. After the complete defeat of the Salassi and the peace treaties, the castrum became a main business crossroads and several houses wooden in bricks and stones, were built around the military camp; when the Christianity expanded in the Roman Empire, Cirié picked up Cyriacus as patron saint, due to the similarity of his name with the ancient castrum denomination. The famous Il celebre Theatrum Statuum Sabaudiae gives a long and detailed description of Cirié and cites the probable origin of the village name as being related to the martyr.

Roman presence in Cirié is funerary stele. From the Fall of Roman Empire and the barbaric invasions, we don't have further information on Cirié for a millennium; the first historical fact known is the occupation of Cirié's area by the Marquis of Montferrat in 1229. In 1296 Marguerite of Savoy marries John I, Marquess of Montferrat, getting ruling rights over the territories of Caselle, Cirié and Lanzo; when her husband dies prematurely, Marguerite moves into the great Castle of Cirié, a big fortress standing where nowadays is the piazza Castello. The coming of Marguerite to Cirié, is celebrated with the Palio dei Borghi, a medieval festival held every two years with tournaments and games. Marguerite began great works in the castle, which became one of the most renowned mansions of the area, with nobles visiting from all over Europe; the many servants coming along with the nobles were hosted by the citizens of Cirié and Marguerite issued "patenti", important acknowledgments of their service to the Marquess.

Marguerite cut taxes and commanded a weekly market to be held each Friday, a commercial venue which attracted many people and business from the neighbors. This market is still held these days; the castle was destroyed during the French invasion of 1536 and the few remains were scattered about 1900 when the square was "modernized". Some friezes, the only remains of the once powerful castle, are now preserved in the San Martino church. In 1576 the Savoy family exchanges the Cirié area with an access to the sea with the Doria Marquis of Genoa: Gian Gerolamo D'Oria establishes his residence in Cirié, starting the long dynasty which ruled the city till the last Marquis Emanuele D'Oria, who becomes the first mayor when Cirié, in force of a royal decree, is established a "city" in 1905. San Giovanni Battista, dates from the 14th century, but the place has been dedicated to worship since the Romans settled in the area. Most a temple of the goddess Diana was erected in this place. A series of Christian churches were established on the site of the former temple.

The current church, in a bright Piedmontese Gothic architecture, has three naves. It has been restored in the late 1800s with some arguable Byzantine flavor by Edoardo Arborio Mella and the facade has been used a model for the church in the Borgo Medievale, a replica of medieval mountain castles of Piedmont and Aosta Valley, built in Turin for the International Exhibition of 1884. for the International Exhibition of 1884. The church has a four-floor bell tower with mullioned windows; the interior houses a Madonna del Popolo from Defendente Ferrari's workshop, a wonderful Byzantine-school crucifix and a triptych by Giuseppe Giovenone da Vercelli so beautiful that it is said king Carlo Alberto offered 4000 lire to have it in the royal art collection Sabauda Gallery, but the p

Ted (album)

Ted is the second album from Swedish singer/songwriter Ted Gärdestad, released in 1973 on the Polar Music label. It contains the hits "Jag Ska Fånga En Ängel", "Sol, Vind Och Vatten", "Come Give Me Love" as well as his 1973 Melodifestivalen entry "Oh Vilken Härlig Da'"; the album was produced by Benny Andersson, Björn Ulvaeus and Ted, engineered by Michael B. Tretow and features vocals by Anni-Frid Lyngstad. An English-language version of the track "Jag Ska Fånga En Ängel" entitled "Gonna Make You My Angel" was released as the B-side of non-album single and Melodifestivalen entry "Rockin"n' Reelin'" in early 1975. "Gonna Make You My Angel" remains unreleased on CD. All lyrics written by Kenneth Gärdestad, music by Ted Gärdestad Side A: "Jag ska fånga en ängel" - 3:50 "Sol, vind och vatten" - 3:10 "Skolsång" - 3:02 "Kaliforniens guld" - 2:37 "Come Give Me Love" - 3:32 "Ramanagaram" - 2:50Side B: "Oh, vilken härlig da'" - 3:21 "Kom i min fantasi" - 2:34 "Universum" - 3:52 "Gitarren och jag" - 3:52 "Stenansiktet" - 4:45 From Jan Halldoff's movie by the same name Ted Gärdestad - lead vocals, acoustic guitar, piano Benny Andersson - piano, vibraphone, Moog synthesizer, backing vocals Björn Ulvaeus - acoustic guitar, mandolin, backing vocals Janne Schaffer - electric guitar Mike Watson - bass guitar Ola Brunkert - drums Roger Palm - drums Rutger Gunnarsson - banjo Agnetha Fältskog - backing vocals Anni-Frid Lyngstad - backing vocals Lena Andersson - backing vocals Luciano Mosetti - harmonica Benny Andersson - producer Björn Ulvaeus - producer Ted Gärdestad - producer Michael B.

Tretow - sound engineer Rune Persson - sound engineer Åke Elmsäter - sound engineer Sven-Olof Walldoff - string arrangements "Universum" and "Kaliforniens Guld" Lasse Samuelsson - brass arrangement Recorded at Metronome Studios, Stockholm Originally released as Polar POLS 241, 1973. Liner notes Ted, Ted Gärdestad, Polar Music POLS 241, 1973. Official home page, The Ted Gärdestad Society