**1. Introduction**

The Colombian Neutron Activation Analysis Laboratory (CNAAL) is a facility used for qualitative and quantitative nondestructive chemical multielemental analysis by activating samples at the Nuclear Research Reactor IAN-R1 and analyzing their decay products using Gamma Spectrometry. Neutron activation analysis (NAA) in Colombia started at the Institute of Nuclear Affairs (IAN) when the nuclear reactor research IAN-R1 first achieved criticality in 1965. This technique has been used for over 30 years mainly for elemental analysis with applications in geology, hydrology, environmental and forensic sciences. In 1998, the Colombian government closed down the Reactor and the country's nuclear development fell behind other Latin American countries who also began their nuclear research applications in the 1960s.

The onset of NAA in Colombia began in the mid-1950s, not long after the United States President Dwight D. Eisenhower gave his atoms for peace speech at the United Nations General Assembly on December 8, 1953. The Atoms for peace program served as shorthand for a number of programs intended to spread the peaceful uses of nuclear physics around the world and demonstrating its usefulness in the fields of medicine and energy generation. In 1955, the Colombian Institute of Nuclear Affairs (ICAN) was created, but it was not until 1957 that the Radioactive Analysis Laboratory was built as part of the ICAN chemistry program [1], being the predecessor of the current Neutron Activation Analysis Laboratory. This laboratory had basic instrumentation for personnel training purposes and was used for radiometric analysis by low-resolution gamma spectrometry using scintillation detectors like NaI(Tl) and single-channel systems.

in the Colombian territory, a similar nuclear technique was implemented at the time which helped improve the precision of analysis: delayed neutron counting (DNC) (**Figure 3**). Delayed neutrons are emitted after nuclear fission events by one of the fission products some-

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**Figure 1.** Nuclear reactor start-up by Colombian president Guillermo León Valencia (1965).

**Figure 2.** Neutron activation analysis instrumentation, Ge-li detection system (1971).

time after the fission process [7].

Colombia was admitted to the International Atomic Energy Agency (IAEA) in the year 1960 and in 1964 began the construction of the dome building where the nuclear reactor stands today, later that same year the country received nuclear fuel manufactured in the United States as a donation by the American government. On January 20, 1965, the nuclear reactor achieved its first criticality (**Figure 1**) and operated at 10 kW during its first months [2].

In 1965, the first NAA samples were irradiated for elemental analysis [3], and the results were published 2 years later in 1967. Many scientific papers were published during this time, out of which two were of particular interest: the determination of inorganic iodine in samples of urine and the determination of trace amounts of selenium and tellurium in sulfur samples [4, 5]. The year 1971 witnessed the arrival of the first high-resolution Gamma Spectrometry System consisting of a germanium-lithium detector coupled to a multichannel analyzer (**Figure 2**). During this year, research focused on petrochemical analysis with the determination of vanadium in oil samples followed by the irradiation of food samples to determine nitrogen content in cereals.

Due to the boom in radioactive mineral exploration activities, the then Institute of Nuclear Affairs promoted a program for the quantitative evaluation of uranium and thorium in Colombia, for which Neutron Activation Analysis was used for the study of radioactive minerals and elemental determination in geological samples [1, 6]. Given the increased demand for this type of analysis and the interest from different companies on radioactive mineral exploration Colombian Neutron Activation Analysis Laboratory (CNAAL): Applications and Development… http://dx.doi.org/10.5772/intechopen.74395 31

**Figure 1.** Nuclear reactor start-up by Colombian president Guillermo León Valencia (1965).

**1. Introduction**

30 Advanced Technologies and Applications of Neutron Activation Analysis

tions in the 1960s.

single-channel systems.

nitrogen content in cereals.

The Colombian Neutron Activation Analysis Laboratory (CNAAL) is a facility used for qualitative and quantitative nondestructive chemical multielemental analysis by activating samples at the Nuclear Research Reactor IAN-R1 and analyzing their decay products using Gamma Spectrometry. Neutron activation analysis (NAA) in Colombia started at the Institute of Nuclear Affairs (IAN) when the nuclear reactor research IAN-R1 first achieved criticality in 1965. This technique has been used for over 30 years mainly for elemental analysis with applications in geology, hydrology, environmental and forensic sciences. In 1998, the Colombian government closed down the Reactor and the country's nuclear development fell behind other Latin American countries who also began their nuclear research applica-

The onset of NAA in Colombia began in the mid-1950s, not long after the United States President Dwight D. Eisenhower gave his atoms for peace speech at the United Nations General Assembly on December 8, 1953. The Atoms for peace program served as shorthand for a number of programs intended to spread the peaceful uses of nuclear physics around the world and demonstrating its usefulness in the fields of medicine and energy generation. In 1955, the Colombian Institute of Nuclear Affairs (ICAN) was created, but it was not until 1957 that the Radioactive Analysis Laboratory was built as part of the ICAN chemistry program [1], being the predecessor of the current Neutron Activation Analysis Laboratory. This laboratory had basic instrumentation for personnel training purposes and was used for radiometric analysis by low-resolution gamma spectrometry using scintillation detectors like NaI(Tl) and

Colombia was admitted to the International Atomic Energy Agency (IAEA) in the year 1960 and in 1964 began the construction of the dome building where the nuclear reactor stands today, later that same year the country received nuclear fuel manufactured in the United States as a donation by the American government. On January 20, 1965, the nuclear reactor achieved its first criticality (**Figure 1**) and operated at 10 kW during its first months [2].

In 1965, the first NAA samples were irradiated for elemental analysis [3], and the results were published 2 years later in 1967. Many scientific papers were published during this time, out of which two were of particular interest: the determination of inorganic iodine in samples of urine and the determination of trace amounts of selenium and tellurium in sulfur samples [4, 5]. The year 1971 witnessed the arrival of the first high-resolution Gamma Spectrometry System consisting of a germanium-lithium detector coupled to a multichannel analyzer (**Figure 2**). During this year, research focused on petrochemical analysis with the determination of vanadium in oil samples followed by the irradiation of food samples to determine

Due to the boom in radioactive mineral exploration activities, the then Institute of Nuclear Affairs promoted a program for the quantitative evaluation of uranium and thorium in Colombia, for which Neutron Activation Analysis was used for the study of radioactive minerals and elemental determination in geological samples [1, 6]. Given the increased demand for this type of analysis and the interest from different companies on radioactive mineral exploration in the Colombian territory, a similar nuclear technique was implemented at the time which helped improve the precision of analysis: delayed neutron counting (DNC) (**Figure 3**). Delayed neutrons are emitted after nuclear fission events by one of the fission products sometime after the fission process [7].

**Figure 2.** Neutron activation analysis instrumentation, Ge-li detection system (1971).

**Figure 4.** NAA instrumentation (1976).

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**Figure 5.** Irradiated samples from 1980 to 1990 [12].

**Figure 6.** NAA laboratory (1989).

**Figure 3.** U/Th analysis by DNC (1974).

As of 1973 and thanks to the support offered by the French Government, NAA was implemented as an alternative to conventional analytical methods for the determination of small quantities of precious metals such as gold, silver, platinum and palladium, among others [8]. For 12 years, from 1975 to 1986, the NAA technique reached its stage of the greatest development and was used as standard for elemental analysis. Thanks to the support given by the IAEA, the country received funds to upgrade its NAA laboratory due to the potential growth of users demanding this type of analysis (**Figure 4**). During this period, the use of NAA in Forensic Sciences was also introduced.

From 1986 to 1989, work focused on improving procedures and methodologies in the application of NAA for mineral resource exploration and studies of sediments and water pollution [9–11]. From 1987 to 1990, there was a drastic decrease in workload (**Figure 5**) due to an upgrade at the nuclear reactor.

Once the reactor was up and running, the laboratory continued its routine analysis, providing services to internal projects as well as to external clients. NAA was used mainly for mining companies and special forensic studies (**Figure 6**) [9]. In 1992, the laboratory was moved to a new space, which was built as an annex to the Reactor's Building with the sole purpose of installing a pneumatic transfer system that would allow for the measurement of short-lived radionuclides (with average half-lives of the order of minutes and seconds).

Colombian Neutron Activation Analysis Laboratory (CNAAL): Applications and Development… http://dx.doi.org/10.5772/intechopen.74395 33

**Figure 4.** NAA instrumentation (1976).

**Figure 5.** Irradiated samples from 1980 to 1990 [12].

As of 1973 and thanks to the support offered by the French Government, NAA was implemented as an alternative to conventional analytical methods for the determination of small quantities of precious metals such as gold, silver, platinum and palladium, among others [8]. For 12 years, from 1975 to 1986, the NAA technique reached its stage of the greatest development and was used as standard for elemental analysis. Thanks to the support given by the IAEA, the country received funds to upgrade its NAA laboratory due to the potential growth of users demanding this type of analysis (**Figure 4**). During this period, the use of NAA in

From 1986 to 1989, work focused on improving procedures and methodologies in the application of NAA for mineral resource exploration and studies of sediments and water pollution [9–11]. From 1987 to 1990, there was a drastic decrease in workload (**Figure 5**) due to an

Once the reactor was up and running, the laboratory continued its routine analysis, providing services to internal projects as well as to external clients. NAA was used mainly for mining companies and special forensic studies (**Figure 6**) [9]. In 1992, the laboratory was moved to a new space, which was built as an annex to the Reactor's Building with the sole purpose of installing a pneumatic transfer system that would allow for the measurement of short-lived

radionuclides (with average half-lives of the order of minutes and seconds).

Forensic Sciences was also introduced.

upgrade at the nuclear reactor.

**Figure 3.** U/Th analysis by DNC (1974).

32 Advanced Technologies and Applications of Neutron Activation Analysis

**Figure 6.** NAA laboratory (1989).

In September 1994, the nuclear reactor went into an extended shutdown period due to modernization of its instrumentation and control systems as well as conversion from highlyenriched uranium (HEU) fuel to low-enriched uranium (LEU) TRIGA fuel. Process took place from 1995 to 1997.

Several expert missions were received for training of new personnel. The first objective of the Laboratory in this new stage was to provide the service of multielement analysis of geological samples, for which the relative method (comparator method in the literature) is used through certified reference materials (CRM) [13, 14]. **Figure 8** shows the state of the labora-

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During the years of 2013 and 2015, the gamma spectrometry systems were modernized with High-Purity Germanium (HPGe) Canberra® detectors (**Figure 9**), an automated positioning system was also installed in the laboratory, making it unique in Latin America. IAEA experts have been continuously assisting on the validation for the test method and neutron flux characterization of the core. Today, thanks to the support given by the IAEA, the nuclear reactor and NAA laboratory have some of the most modern installations in Latin America with

strong future prospectives in various fields of science.

tory in 2009.

**Figure 8.** NAA laboratory (2009).

**Figure 9.** NAA laboratory (2017).

In spite of the liquidation in 1997 of the Institute of Nuclear Sciences and Alternative Energies (Formerly Institute of Nuclear Affairs), the nuclear reactor still operated with its new TRIGA fuel and was utilized for the analysis of forensic samples needed by the Police Department for the determination of barium, antimony and copper. During the first quarter of 1998, forensic samples were analyzed for the determination of mercury in hair, but due to the closure of the institute, the Reactor was shut down on March 31 that same year [3]. This series of events halted the operational experience that the NAA Laboratory had built for about 32 years (**Figure 7**).

It was not until 2005 that the Colombian Government decided to restart its Nuclear Program and began training personnel at the Reactor and associated nuclear laboratories. In May 2006 with support from the IAEA, the NAA technique was finally resumed, and tests were performed for the two Gamma Spectrometry Systems available at the time. One system equipped with a NaI(Tl) scintillation detector and the other with a Canberra 7229P HPGe semiconductor detector.

However, the NAA laboratory formally resumed activities in 2009, when the authorization for radioactive material handling was granted by the National Regulatory Authority.

**Figure 7.** Gamma spectrometry system (1997).

Several expert missions were received for training of new personnel. The first objective of the Laboratory in this new stage was to provide the service of multielement analysis of geological samples, for which the relative method (comparator method in the literature) is used through certified reference materials (CRM) [13, 14]. **Figure 8** shows the state of the laboratory in 2009.

During the years of 2013 and 2015, the gamma spectrometry systems were modernized with High-Purity Germanium (HPGe) Canberra® detectors (**Figure 9**), an automated positioning system was also installed in the laboratory, making it unique in Latin America. IAEA experts have been continuously assisting on the validation for the test method and neutron flux characterization of the core. Today, thanks to the support given by the IAEA, the nuclear reactor and NAA laboratory have some of the most modern installations in Latin America with strong future prospectives in various fields of science.

**Figure 8.** NAA laboratory (2009).

In September 1994, the nuclear reactor went into an extended shutdown period due to modernization of its instrumentation and control systems as well as conversion from highlyenriched uranium (HEU) fuel to low-enriched uranium (LEU) TRIGA fuel. Process took place

In spite of the liquidation in 1997 of the Institute of Nuclear Sciences and Alternative Energies (Formerly Institute of Nuclear Affairs), the nuclear reactor still operated with its new TRIGA fuel and was utilized for the analysis of forensic samples needed by the Police Department for the determination of barium, antimony and copper. During the first quarter of 1998, forensic samples were analyzed for the determination of mercury in hair, but due to the closure of the institute, the Reactor was shut down on March 31 that same year [3]. This series of events halted the operational experience that the NAA Laboratory had built for about 32 years

It was not until 2005 that the Colombian Government decided to restart its Nuclear Program and began training personnel at the Reactor and associated nuclear laboratories. In May 2006 with support from the IAEA, the NAA technique was finally resumed, and tests were performed for the two Gamma Spectrometry Systems available at the time. One system equipped with a NaI(Tl) scintillation detector and the other with a Canberra 7229P HPGe semiconduc-

However, the NAA laboratory formally resumed activities in 2009, when the authorization for radioactive material handling was granted by the National Regulatory Authority.

from 1995 to 1997.

34 Advanced Technologies and Applications of Neutron Activation Analysis

(**Figure 7**).

tor detector.

**Figure 7.** Gamma spectrometry system (1997).

**Figure 9.** NAA laboratory (2017).
