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PUBLIC HEALTH ASSESSMENT

PUBLIC HEALTH IMPLICATIONS OF RADIATION CONTAMINATION AT
FORMER CLOCK FACTORIES LOCATED IN
BRISTOL (HARTFORD COUNTY), NEW HAVEN (NEW HAVEN COUNTY), THOMASTON (LITCHFIELD COUNTY), AND WATERBURY (NEW HAVEN COUNTY)
CONNECTICUT


DISCUSSION

Radiation Surveys

Radiation surveys included gamma, alpha, beta radiation, and radon gas sampling. The gamma radiation measurements included direct contact, and waist level or general area readings. The waist level readings are measured at three feet from the suspected source.

The alpha and beta radiation measurements were reported as either fixed or smearable. The smearable results indicate that radioactive contamination is present. The units of radiation are dependent on the radiation type and measurement techniques. Gamma radiation is generally reported in uR/hr (micro Roentgen per hour). Alpha and beta radiation units are either reported as counts per minute (cpm) or disintegrations per minute (dpm). The value of dpm will always be greater than the value for counts per minute, since the efficiency for the alpha detector is approximately 30 percent and the beta/gamma detector is approximately 10 percent. Radon is a radioactive gas that is a decay product of radium. The units of measurement are pCi/L (pico Curie per liter).

The CT DEP requested radiological assistance from the US Department of Energy (DOE) on April 1, 1998. Surveying was conducted from April 2, 1998, to April 7, 1998.

On April 2, 1998, the DOE/CT DEP team conducted sampling at the Waterbury Clock Company including, the Ville Swiss Automatics and Belco.

On April 3, 1998, the investigation proceeded to the former Lux Clock Company in Waterbury.

On April 6, 1998, the radiation survey investigated the former Seth Thomas Clock company in Thomaston, as well as the former Benrus Clock Company in Waterbury.

On April 7, 1998, the Thomaston radiation survey was completed, and a separate survey was conducted in New Haven.

The results of the radiation surveys are presented below in Tables 2 through 14. Each table identifies the town name, former clock company name, current occupant, location of sample, maximum radiation levels detected, background levels, and the relevant comparison value. In 1997, EPA issued OSWER Directive 9200.4-18, Establishment of cleanup levels for Superfund sites with radioactive contamination. This directive provides guidance for establishing protective cleanup levels for radioactive contamination at Superfund sites. Using this directive, an effective dose of 15 mRem/yr equates to an increased lifetime risk of 3 in 10,000 of cancer, serving as the upper bounds of EPA acceptable risk. This would include exposures from all pathways, and through all media (e.g., soil, ground water, surface water, sediment, air, structures, biota).

Results of Radiation Surveys

Table 2. Town: Bristol
Clock Company Name: Sessions Clock Company
Current Occupant(s): DABKO CO.
Radiological Parameter
(units) 		Location Floor Measurement
Description 		Maximum
Level 		Background CL
Gamma radiation
(uR/hr) 		Building A 2nd floor not applicable 0 NR 15
3rd floor not applicable 0
4th floor not specified 120
Building D 2nd floor not applicable 0 NR NR
3rd floor not specified 40

CL = EPA Cleanup Level
NR = not reported
uR/hr = Micro Roentgen per hour


Table 3. Town: Bristol
Clock Company Name: Sessions Clock Company
Current Occupant(s): Bristol Instrument Gears
Radiological
Parameter (units)		 Location Measurement
Description		 Maximum Level Background CL
Gamma radiation
(uR/hr)		 1st floor Direct contact 15 5 15
Measured at Waist level 12
Alpha, Beta gamma activity   not measured      

CL = EPA Cleanup Level
uR/hr = Micro Roentgen per hour


Table 4. Town: New Haven
Clock Company Name: New Haven Clock Company
Current Occupant(s): Goodies Repairs
Radiological Parameter (units) Location Measurement Description Maximum Level Background CL
Gamma radiation (uR/hr) 1st floor Direct contact 35 10 15
Measured at Waist level 13
Alpha, Beta gamma activity   not measured      

CL = EPA Cleanup Level
uR/hr = Micro Roentgen per hour


Table 5. Town: Thomaston
Clock Company Name: Seth Thomas Clock Company
Current Occupant(s): Various Companies
Radiological Parameter (units) Location Measurement Description Maximum Level Background CL
Gamma radiation (uR/hr) 1st floor Direct contact 100 12 15
General Area 40
2nd floor Direct contact 80
General Area 25
3rd floor Direct contact 650
General Area 80
4th floor Direct contact 45
General Area 12
Alpha activity (net cpm)
DP
(cpm/100 cm2)
DP
(cpm/100 cm2)
DP
(cpm/100 cm2)
DP
(cpm/100 cm2)
 1st floor Fixed 0 0 300
20*
Measurement of Loose Material (Smear) 0 0
2nd floor Fixed not measured NR 300
20
Measurement of Loose Material (Smear) 0 0
3rd floor Fixed 100 0 300
20
Measurement of Loose Material (Smear) 10 0
4th floor Fixed 550 0 300
20
Measurement of Loose Material (Smear) 50 0
Beta Gamma activity (net cpm)
DP
(cpm/100 cm2)
DP
(cpm/100 cm2)
DP
(cpm/100 cm2)
DP
(cpm/100 cm2)
 1st floor Fixed 6,000 50 300
20
Measurement of Loose Material (Smear) 0 50
2nd floor Fixed 500 50 300
20
Measurement of Loose Material (Smear) 0 0
3rd floor Fixed 3,000 50 300
20
Measurement of Loose Material (Smear) 30 50
4th floor Fixed 1,300 50 300
20
Measurement of Loose Material (Smear) 30 50

CL = EPA Cleanup Level
cpm = counts per minute
dpm = disintegrations per minute
NR = not reported, background counting rates ranged from 0.2-0.3 cpm for alpha, and 30-50 cpm for beta/gamma.
uR/hr = Micro Roentgen per hour
*The cpm units can be converted into dpm units, however the calibration isotope is required for this. In general, if an unconverted cpm value exceeds the dpm cleanup level, then the converted value will also be greater.


Table 6. Town: Waterbury
Clock Company Name: Benrus Clock Company
Current Occupant(s): Bender Plumbing
Radiological Parameters (units) Location Measurement Description Maximum Level Background CL
Gamma radiation (uR/hr) 1st floor Direct contact 0 10 15
Measured at Waist level 0
2nd floor Direct contact 0
Measured at Waist level 0
3rd floor Direct contact 0
Measured at Waist level 0
4th floor Direct contact 120
Measured at Waist level 26
5th floor Direct contact 40
Measured at Waist level 15
6th floor Direct contact 0
Measured at Waist level 0
7th floor Direct contact 600
Measured at Waist level 100
Radon-222 (pCi/L) 4th floor Not applicable 1.0 NR 4

CL = EPA Cleanup Level
NR = not reported
pCi/L = Pico Curries per Liter
uR/hr = Micro Roentgen per hour


Table 7. Town: Waterbury
Clock Company Name: Lux Clock Company
Current Occupant(s): Anchor Advanced Products
Radiological Parameters (units) Location Measurement Description Maximum Level Background CL
Gamma radiation (uR/hr) 1st floor Direct contact 20 10 15
2nd floor Direct contact 20
3rd floor Direct contact 30
4th floor Direct contact 140
Alpha Beta activity(dpm) 1st floor Measurement of Loose Material (Smear) not measured NR 20
2nd floor Measurement of Loose Material (Smear) not measured NR
3rd floor Measurement of Loose Material (Smear) not measured NR
4th floor Measurement of Loose Material (Smear) 150 NR

CL = EPA Cleanup Level
dpm = disintegrations per minute
NR= not reported, background counting rates ranged from 0.2-0.3 cpm for alpha, and 30-50 cpm for beta/gamma.
uR/hr = Micro Roentgen per hour


Table 8. Town: Waterbury
Clock Company Name: Waterbury Clock Company
Current Occupant(s): Belco 2nd floor
Radiological Parameter (units) Location Measurement Description Maximum Level Background CL
Gamma radiation (uR/hr) Cutting Room Direct contact 55 10 15
Measured at Waist level 55
Machine Room Direct contact 140
Measured at Waist level 140
Alpha activity(dpm/100 cm2) Cutting Room Measurement of Loose Material (Smear) <MDA NR 20
Machine Room Measurement of Loose Material (Smear) 150 NR
Beta Gamma activity(dpm/100 cm2) Cutting Room Measurement of Loose Material (Smear) <MDA NR 20
Machine Room Measurement of Loose Material (Smear) 232 NR

<MDA = less than minimum detected activity
CL = EPA Cleanup Level
dpm = disintegrations per minute
NR = not reported, background counting rates ranged from 0.2-0.3 cpm for alpha, and 30-50 cpm for beta/gamma.
uR/hr = Micro Roentgen per hour


Table 9. Town: Waterbury
Clock Company Name: Waterbury Clock Company
Current Occupant(s): Belco 3rd floor Highest radiation level detected
Radiological Parameter (units) Location Measurement Description Maximum Level Background CL
Gamma radiation (uR/hr) Hallway Direct contact 5,000 10 15
Measured at Waist level 1,500
Store room Direct contact 3,200
Measured at Waist level 250
Liba room Direct contact 300
Measured at Waist level 52
Alpha activity (dpm/100 cm2) Hallway Measurement of Loose Material (Smear) 7,985 NR 20
Store room Measurement of Loose Material (Smear) 4,438 NR
Liba room Measurement of Loose Material (Smear) 328 NR
Beta Gamma activity (dpm/100 cm2) Hallway Measurement of Loose Material (Smear) 16,636 NR 20
Store room Measurement of Loose Material (Smear) 9,242 NR
Liba room Measurement of Loose Material (Smear) 695 NR

CL = EPA Cleanup Level
dpm = disintegrations per minute
NR = not reported, background counting rates ranged from 0.2-0.3 cpm for alpha, and 30-50 cpm for beta/gamma.
uR/hr = Micro Roentgen per hour


Table 10. Town: Waterbury
Clock Company Name: Waterbury Clock Company
Current Occupant(s): Belco 4th floor
Radiological Parameter (units) Location Measurement Description Maximum Level Background CL
Gamma radiation (uR/hr) Store room Direct contact 120 10 15
Measured at Waist level 70
Radon-222 (pCi/L) 4th floor not applicable 6.5 NR 4
Alpha activity (dpm/100 cm2) Store room Measurement of Loose Material (Smear) 19 NR 20
Beta Gamma activity (dpm/100cm2) Store room Measurement of Loose Material (Smear) <MDA NR 20

CL = EPA Cleanup Level
dpm = disintegrations per minute
NR = not reported, background counting rates ranged from 0.2-0.3 cpm for alpha, and 30-50 cpm for beta/gamma.
pCi/L = Pico Curries per Liter
uR/hr = Micro Roentgen per hour


Table 11. Town: Waterbury
Clock Company Name: Waterbury Clock Company
Current Occupant(s): Belco 5th floor
Radiological Parameter (units) Location Measurement Description Maximum Level Background CL
Gamma radiation (uR/hr) Rental area Direct contact 800 10 15
Measured at Waist level 800
Alpha activity (dpm/100 cm2) Rental area Measurement of Loose Material (Smear) 247 NR 20
Beta Gamma activity(dpm/100 cm2) Rental area Measurement of Loose Material (Smear) 516 NR 20

CL = EPA Cleanup Level
dpm = disintegrations per minute
NR = not reported, background counting rates ranged from 0.2-0.3 cpm for alpha, and 30-50 cpm for beta/gamma.
uR/hr = Micro Roentgen per hour


Table 12. Town: Waterbury
Clock Company Name: Waterbury Clock Company
Current Occupant(s): Enterprise Apartments
Radiological Parameters (units) Location Measurement Description Maximum Level Background CL
Gamma radiation (uR/hr) 1st floor Direct contact 0 10 15
Measured at Waist level 0
2nd floor Direct contact 0
Measured at Waist level 0
3rd floor Direct contact 0
Measured at Waist level 0
4th floor
Apt 417		 Direct contact 240
Measured at Waist level 15
5th floor
Apt 505 		Direct contact 30 7
Measured at Waist level 12
5th floor
Apt 507 		Direct contact 90 10
Measured at Waist level 30
5th floor
Apt 508 		Direct contact 28 8
Measured at Waist level 12
5th floor
Apt 512 		Direct contact 30 7
Measured at Waist level 15
5th floor
Apt 513 		Direct contact 45 8
Measured at Waist level 15
5th floor
Apt 514 		Direct contact 100 10
Measured at Waist level 30
5th floor
Apt 515 		Direct contact 110 8
Measured at Waist level 20
5th floor
Apt 516 		Direct contact 25 12
Measured at Waist level 15
5th floor
Apt 517 		Direct contact 120 10
Measured at Waist level 18
5th floor
Apt 520 		Direct contact 30 10
Measured at Waist level 15
5th floor
Apt 525 		Direct contact 70 8
Measured at Waist level 12
5th floor
Hall		 Direct contact 800 8
Measured at Waist level 80
Radon-222 (pCi/L) 4th floor Not applicable 1.5 NR 4

CL = EPA Cleanup Level
NR = not reported
pCi/L = Pico Curries per Liter
uR/hr = Micro Roentgen per hour


Table 13. Town: Waterbury
Clock Company Name: Waterbury Clock Company
Current Occupant(s): NOW 3rd through 5th Floors
Radiological Parameters (units) Location Measurement Description Maximum Level Background CL
Gamma radiation (uR/hr) 3rd floor Direct contact 60 10 15
Measured at Waist level 18
4th floor Direct contact 180 12
Measured at Waist level 35
5th floor Direct contact 4,000 12
Measured at Waist level 125
Radon-222 (pCi/L) 3rd floor Not applicable 0.8 NR 4
4th floor Not applicable 8.5

CL = EPA Cleanup Level
NR = not reported
pCi/L = Pico Curries per Liter
uR/hr = Micro Roentgen per hour


Table 14. Town: Waterbury
Clock Company Name: Waterbury Clock Company
Current Occupant(s): Ville Swiss Automatics Automotive 3rd through 5th Floors
Radiological Parameters (units) Location Measurement Description Maximum Level Background CL
Gamma radiation (uR/hr) 1st floor Direct contact Nd
15
Measured at Waist level Nd
2nd floor Direct contact Nd
Measured at Waist level Nd
3rd floor Direct contact 100 20
Measured at Waist level 20
4th floor Direct contact 40 20
Measured at Waist level 20
5th floor Direct contact 40 13
Measured at Waist level 13
Radon-222 (pCi/L) 4th floor Not applicable 0.3
4

CL = EPA Cleanup Level
Nd = none detected
pCi/L = Pico Curries per Liter
uR/hr = Micro Roentgen per hour


Radium Toxicity

Studies have shown that internal deposition of 226Ra results in the induction of skeletal tumors and paranasal sinus carcinomas (cancer of the sinus cavities) (3, 4). Argonne National Laboratory and its' Center for Human Radiobiology have studied the human health effects of radium deposition for over 20 years. Stebbings, et al. (5) reported that in U.S. white females employed as dial painters, the rates of liver, pancreatic, cervical, and uterine cancers were not related to radium exposure. Some cancers of the digestive system, however, may have been indirectly related to radium exposure. They reported that although, there was an increase in multiple myeloma (a form of leukemia), indications were that this increase was related more to the length of employment as a dial painter than the amount of radium in the body. This indirectly suggests the myeloma may be due to the external exposure to the gamma radiation emitted during the radioactive decay of 226Ra.

The major health effects resulting from internally deposited 226Ra are noted in cases dealing with occupational exposure, the majority being radium dial painters. The alpha particle is the major type of damaging radiation from internalized (inhaled or ingested) 226Ra. This decay particle travels very short distances within the body and the majority, if not all its energy is absorbed within the body part where the 226Ra is deposited. 226Ra has chemical characteristics similar to calcium therefore, most of the ingested 226Ra deposits in bones where the greatest exposure and dose is delivered to bone surfaces and perhaps the blood-forming bone marrow. Additionally, more specific information regarding 226Ra is given in Appendix A.

As of 1984, almost 6,000 individuals with all types of exposure to radium had been located throughout the United States (6). Of the 6,000 identified, 1,907 dial painters were located and had their radium body burden measured. In this group, there were 44 cases of bone tumors and 19 cases of sinus or mastoid (associated with the head) carcinomas. These totals include three individuals with both types of illnesses. The study concluded that these illnesses and skeletal tissue deterioration were nevertheless unquestionably related to the presence of internal radium.


Radiation doses and related information: International and National

The National Council on Radiation Protection and Measurements (NCRP) is a non-governmental body that makes recommendations to the radiation protection community within the United States. In 1987, the NCRP recommended that in the case of continuous or frequent exposure to radiation, a population should not exceed 1 milliSieverts (mSv; 100 milliRem per year [mRem/yr]) above background. For a population infrequently exposed, a limit of 5 mSv (500 mRem/yr) was recommended (7). In 1994, the NCRP reaffirmed and refined these exposure limits (8).

Smear Samples

The radiation protection industry has adopted stringent, acceptable levels of surface contamination that is fixed in place (non-removable) or that which can be removed from the contaminated surface. In the case of removable contamination, these levels are determined by taking a surface smear from a square meter area and averaging the results per 100 square centimeters (cm2). The radioactive material collected by this procedure is analyzed for the specific radionuclide. For non-removable 226Ra, the average allowable limit is 100 dpm per 100 cm2, and the maximum allowable limit in any 100 cm2 area is 300 dpm. If more than 20 dpm can be removed, then the contaminated surface exceeds these federal standards (9).

The US Environmental Protection Agency (EPA) uses Applicable or Relevant and Appropriate Requirements (ARAR) which, in many cases, serve as the determining factor for site cleanup. Because the contamination in these non-Superfund facilities are not specifically addressed by ARAR values, the EPA can set site specific cleanup levels. In 1997 EPA issued OSWER Directive 9200.4-18. Establishment of cleanup levels for Superfund sites with radioactive contamination (10). This directive provides guidance for establishing protective cleanup levels for radioactive contamination at superfund sites. Using this directive, an effective dose of 0.15 milliSieverts (mSv; 15 mRem/yr) equates to an increased lifetime cancer risk of 3 in 10,000, serving as the upper bounds of EPA acceptable risk.

Discussion of removable contamination

Removable contamination indicates how easily radiologic contamination might be transferred to humans or other surfaces. This is performed by using a standard size paper swab and gently but firmly rubbing the paper over an area of 100 square centimeters. The paper is then checked for type of radioactivity removed and the results are expressed as disintegrations per minute (dpm) per 100 square centimeters (cm2) of surface. Surface contamination limits have been established for 226Ra (9); the limit for removable 226Ra contamination is 20 dpm/100 cm2.

Discussion of Results

The following section summarizes the results presented in the tables above. This section describes the results stratified by town and presents an overview of the radiation surveys conducted thus far. Locations that have not been fully characterized (identified previously pending data) are also discussed.

Bristol:
All facilities in the Sessions Clock Company were examined. Radiation was detected in two locations above the EPA risk-based cleanup level in two buildings. The locations included: a storage area on the 4th floor of building A, the other was located in an area designated as an old storage area on the 3rd floor of building D. These areas are not currently occupied. One area of the first floor of the Bristol Instrument Gears building was affected with radiation levels at the EPA risk-based cleanup level.
 
New Haven:
Club International is the current occupant of the four story building associated with the former New Haven Clock Company buildings. The first two floors are not affected, the third and fourth floors are pending further investigations.
 
Goodies Repairs is the current occupant of the two story building associated with the former New Haven Clock Company buildings. The first floor has one small spot identified as containing radiation levels above the EPA risk-based cleanup level. The second floor is pending further investigations.
 
St. John's Restaurant is the current occupant of the second four story building associated with the former New Haven Clock Company buildings. The first floor is not affected. The second through fourth floors are pending further investigations. There are several abandoned building also associated with the former New Haven Clock Company. These structures range in size from four to six floors. These have not been fully characterized and are pending further investigations.
 
Thomaston:
The Former Seth Thomas Clock Company was affected with radiation in isolated areas on the first through the fourth floors. Two companies located in the basement and a social club on the fourth floor are pending further investigations. The basement of this structure contains two areas not characterized and one identified as unaffected. The first floor was only affected in one facility, the Verka Enterprise. The second floor was affected in two locations which include the Gaynor Electric facility and WTM. The affected locations on the third floor included the Power Trans facility, the Global Spice Company, and J. McGowan facility. The fourth floor location identified as containing radiation levels above the EPA risk-based cleanup level is the storage area.

Waterbury-Benrus Clock Company:
Radiation levels were above the EPA risk-based cleanup level in isolated areas of the fourth, fifth, and seventh floors of the former Benrus Clock Company building. The current occupant is Bender Plumbing.

Waterbury-Lux Clock Company:
Radiation levels were above the EPA risk-based cleanup level in isolated areas of the first through the fourth floors of the former Lux Clock Company building. The current occupant is Anchor Advanced Products, which is also known as Lakewood Metals.

Waterbury-Waterbury Clock Company:
The affected areas of the former Waterbury Clock facility currently occupied by the Belco company include the cutting room and machine shop in the second floor; the store room, hallway, and Liba section of the third floor, the store room on the fourth floor, and the rental area of the fifth floor. The highest detected levels of radiation above the EPA risk-based cleanup level were located on the third floor hallway. This section is not frequently used. The radiation source has been covered with tape. The tape was used to prevent loose material from being relocated by accidental contact. This procedure will not, however, reduce gamma radiation levels emitted from that location.
 
Many of the areas within the Belco facility were checked for removable contamination using the procedure discussed in the previous section. The results indicated that in all areas checked, the removable contamination was positively identified as 226Ra, and exceeded the regulations. These areas included: 1) the second floor machine shop 2) the third floor store room, hallway, and Liba 3) the fourth floor store room and 4) the fifth floor rental areas. In these areas, the removable alpha contamination ranged from approximately 20 dpm/100 cm2 to over 7,900 dpm/100 cm2. These areas contained beta/gamma removable contamination at levels ranging from approximately 200 dpm/100 cm2 to over 16,600 dpm/100 cm2. Because there is insufficient information as to the amount of dust loading in these areas, additional dose assessment is not possible at this time
 
The occupant of a second Former Waterbury Clock facility is the New Opportunities for Waterbury (NOW). This structure has thirteen offices identified as containing radiation levels above the EPA risk-based cleanup level. The third floor contains one of these offices, the fourth floor houses eight, and the fifth floor has four of these offices.
 
The five story building associated with the former Waterbury Clock Company which houses Ville Swiss Automatics Automotive is affected on isolated areas of the third through fifth floors.
 
Enterprise Apartments is located in another structure also associated with the former Waterbury Clock Company. This complex has radiation levels above the EPA risk-based cleanup level in isolated areas of one fourth floor apartment and in isolated areas of nine 5th floor apartments. Additionally a section of the fifth floor hallway is affected. Two additional apartments on the fifth floor contained radiation levels slightly below the EPA risk-based clean up levels at waist level, but exceeded this value with direct contact readings.

Pathway Analysis

To determine whether occupants, workers, or visitors have been or are being exposed to radiation, the CT DPH and the ATSDR evaluate the environmental and human exposure and an exposed population. There are three types of exposures when radium is present:
- gamma ray exposure occurs when people are near the radium;
- radon exposure, occurs when radium decays into radon and is inhaled (breathed); and
- radium dust exposure occurs through inhalation, dermal contact (direct contact with the skin), and ingestion (through the mouth) of dust.

The pathways analysis consist of: the source of contamination, a point of exposure, a route of exposure, and an exposed population. The ATSDR categorizes exposure pathways as either completed or potential pathways. For an exposure pathway to be completed all elements of the pathway must be present. Potential pathways are those where there is not sufficient evidence to show that all the elements are present now, could be present in the future, or were present in the past.

Completed exposures have occurred to gamma ray and radon exposure to radium and radon. There is insufficient information to determine whether dust containing radium is present in the air of the affected buildings. In addition, there is insufficient information regarding current or past exposures to dust on any surface in the affected buildings. Consequently, the exposure pathway involving dust is considered potential.

Public Health Implications
Occupants of buildings identified with radium radiation levels above 15 mRem/yr may be at a low increased risk of developing bone cancer. This risk may be characterized as higher at locations where the radiation source has been identified as moveable (smearable). These locations may be exposing occupants to an additional health risk due to inhalation and incidental ingestion of radium-contaminated dust particles. Additionally, elevated levels of radon gas were detected in the 4th floor of the Waterbury Clock Company building which now houses Belco. This concentration of radon gas may increase the risk of developing lung cancer among occupants of that facility. The source of the radon gas is from the radiation decay products of 226Ra.


Conclusions

  1. The former Waterbury Clock factory buildings are contaminated in isolated areas with radioactive material emitting radiation at levels (as measured at waist level) that may pose a public health hazard to occupants of the buildings.

  2. The former Sessions Clock Company in Bristol (in isolated areas of the fourth floor of building A and in isolated areas of the third floor of building D) are contaminated with elevated levels of radiation. The CT DPH understands that the locations where the radiation was detected is not currently occupied. However, if the use of these locations changes, occupants may be exposed to radiation at levels of a public health hazard. The Bristol Instrument Gears Company has radiation levels at the EPA risk-based cleanup level.

  3. The former Seth Thomas Clock Company in Thomaston (in isolated areas of the first through the fourth floors) are contaminated with elevated levels of radioactive material. The occupants may be exposed to radiation at levels considered a public health hazard.

  4. Many of the areas within the Belco facility were checked for removable contamination, and the results indicated that sections of each floor were contaminated with removable 226Ra which exceeded the regulations. These areas included: 1) the second floor machine shop 2) the third floor store room, hallway, and Liba 3) the fourth floor store room and 4) the fifth floor rental areas.

  5. Two sites, included as part of these radiation scoping surveys, have data gaps in New Haven and Thomaston. Specifically, the data gaps for the New Haven site include the third and fourth floors of the building which houses Club International, as well as the second through fourth floors of the building which currently houses St. John's Restaurant. The data gaps for the Thomaston site include two areas located in the basement, and a social club located on the fourth floor.

  6. Locations that have been adequately characterized and do not contain radiation levels above background, represent no public health hazard to the occupants.

Recommendations

  1. Dissociate people from areas contaminated with radiation at levels exceeding the EPA directive for establishing protective cleanup levels for radioactive contamination (15 mRem/yr). The following table lists the locations of elevated radiation levels:

Recommendations (continued)
Town Clock Company Current Occupant Floor Location
Bristol Sessions Clock Company DABKO CO 4th floor* Building A
3rd floor* Building D
Bristol Instrument Gears 1st floor*  
New Haven New Haven Clock Company Goodies Repair 1st floor*  
Thomaston Seth Thomas Clock Company Various Companies 1st floor*  
2nd floor*  
3rd floor*  
4th floor*  
Waterbury Lux Clock Company Anchor Advanced Products 1st floor*   
2nd floor*   
3rd floor*  
4th floor*  
Benrus Clock Company Bender Plumbing 4th floor*  
5th floor*  
7th floor*  
Waterbury Clock Company Belco 2nd floor* Cutting Room
Machine Room
3rd floor* Hallway
Store room
Liba room
4th floor* Store room
5th floor* Rental area
Enterprise Apartments 4th floor* Apt 417
5th floor* Apt 505 **
Apt 507
Apt 508
Apt 512
Apt 513
Apt 514
Apt 515
Apt 516
Apt 517
Apt 520
Apt 525 **
Hall
New Opportunities for Waterbury 3rd floor*  
4th floor*  
5th floor*  
Ville Swiss Automatics Automotive 3rd floor*  
4th floor*  
5th floor*  

* Only isolated areas of the floors listed were affected.
** These apartments were slightly below the EPA risk-based cleanup levels at waist level, but exceeded this value on direct contact.

  1. Mark all areas identified as containing radioactive contamination exceeding the EPA cleanup level of 15 mRem/yr.

  2. Complete full radiation characterization surveys of all sites. Specifically, the following locations are pending further investigations in the New Haven Clock Company buildings: the third and fourth floors of the Club International Building, the second floor of the Goodies Repairs building, the second through the fourth floors of the building which houses St. John's Restaurant, and the multiple abandoned buildings. Additionally, the former Seth Thomas Clock Company in Thomaston has areas in the basement, and on the fourth floor that are pending further investigations.

  3. ATSDR and the Connecticut Department of Public Health recommend that the amount of radioactive dust on the floors and in the air be determined in order to assess the radiologic inhalation and ingestion doses from 226Ra.

  4. Inform occupants of all buildings of the findings of this Public Health Assessment.

  5. Radon sampling should be conducted to further characterize sites.

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