SUGAR LAND, Texas – Nearly two years after the accidental release of radioactive material at a Sugar Land facility, city leaders are still asking how it happened and why they weren't immediately notified.

On April 14, 2015, there was an accidental release of Cesium 137 inside the Thermo Fisher Scientific building on Gillingham Lane.

At the time of the incident, the Thermo Fisher facility handled the repair and disposal of gauges used in the petrochemical and oil industries.

"I knew whatever happened was not a good thing," said David Foley, an electrical contractor working in the building. "I happen to be standing there when it happened."

According to an event report by the Nuclear Regulatory Commission, a container of Cesium 137 ruptured while a technician was opening a gauge. The Centers For Disease Control reports Cesium 137 is produced by nuclear fission and in large doses can cause burns, radiation or even death.

"He looked at me and said, 'Stop what you're doing,' and then said, 'You need to leave,' and I could tell the way he was looking around for something he couldn't find that something bad had happened," Foley said.

"When you left the facility the day of the incident, did you think you had anything on you?" asked KPRC investigative reporter Robert Arnold.

"No, no, I didn't think I did," Foley said.

Foley said he was checked for contamination and went home. Court records filed as part of a federal lawsuit claim he did have radioactive material on his clothes. Court records state that on April 18 environmental contractors checked Foley's house.

"They didn't get 20 feet into the house and they said we had to leave," Foley said. "Yep, just like that, spur of the moment."

"Overnight or extended?" Arnold asked.

"Clothes on your back; we're going to scan you as you go out the door," Foley said.

Court records show Foley's home was contaminated.

"Cushions, pillow, couch, recliner, towels, clothes. Mostly things of that nature," Foley said.

At Thermo Fisher's expense, Foley and his wife spent five months in a hotel and bought new clothes while his home and car were cleaned. Foley said he was assured none of the radioactive materials in his system, home or car were at a level that would hurt him.

"It's not permanent. There's not going to be damage," Foley said.

Foley still sued the company, saying since he was a contractor and not a direct employee he was concerned he would be treated as an outsider. Foley settled the case out-of-court and signed a nondisclosure agreement.

"Thermo Fisher did everything they could for us," Foley said.

However, Channel 2 Investigates learned what happened to Foley was not isolated. State records show other employees had low, non-harmful levels of radioactive material in their homes and cars. According to the city of Sugar Land, more radioactive materials wound up in a city ditch plus six other properties in the industrial area where Thermo Fisher is located.

City officials said in addition to Cesium 137, Americium-241 was also found. The Centers for Disease Control reports Americium 241 is a man-made metal produced from plutonium. According to the CDC, high levels of Americium 241, in powder or dust form, can cause certain types of cancers.

According to the company, radioactive material other than Cesium 137 "stemmed from a previous incident."

"We haven't gotten a definitive answer as to how that occurred," said Doug Adolph, with the city of Sugar Land, in reference to radioactive material escaping the building.

"I would think that would bother the city," Arnold said.

"It did bother the city," Adolph said. "Quite frankly, we haven't gotten a good explanation as to how the materials got outside the facility."

Adolph said Sugar Land residents are lucky, none of the radioactive levels found outside of Thermo Fisher are considered harmful to people, something double-checked by the state and independent contractors.

"You would have to lay in that ditch for a period of a year before you were exposed to the same amount of radiation that you would get in a typical doctor visit," Adolph said.

In addition to not knowing exactly how the materials got out, Adolph said something else bothered city leaders. The city of Sugar Land was never notified there even was an incident involving the release of radioactive materials until reporters started calling with questions.

"We immediately contacted the State Health Services Department to find out exactly what was going on over there," Adolph said. "Our expectation is yes, we should be notified."

Adolph said state officials explained that since the levels of radiation were too low to be a public health threat, there was no requirement to notify the city. Thermo Fisher did notify the Department of State Health Services as is required. Through an agreement with the Nuclear Regulatory Commission, the Texas Department of State Health Services licenses and regulates facilities handling radioactive material.

"I am not happy with the fact that they did not find out about this until about a week later," said state Rep. Rick Miller, whose district includes Sugar Land.

Miller said he is in talks with Health Services staff about what can be done to ensure the city is notified if future incidents arise. Miller said he is also pushing for answers as to why the release wasn't contained inside the building.

"We need answers as to how this really happened and what Thermo is going to do about," Miller said.

Thermo Fisher did sign an agreement with Sugar Land to pay for clean up of the ditch, surrounding areas and continued monitoring. The city announced clean up of the ditch has recently been completed.

"It can't cost our taxpayers a dime and that's exactly what occurred," Adolph said.

Officials with DSHS declined to speak with KPRC on camera; citing an ongoing investigation into the incident. KPRC did send DSHS several questions via email and you can read the responses here.

KPRC asked Thermo Fisher the same questions we asked the state and whether the company has changed any procedures following the incident in Sugar Land. We received a written statement.

"We are currently conducting work at our facility on Gillingham Road in Sugar Land as part of an ongoing remediation and restoration effort to locate and remove particles containing low levels of radioactive material from the site and adjacent area, including a nearby ditch that is owned by the city of Sugar Land. In the course of screening the facility, we identified contamination that stemmed from a previous incident. We are in the process of removing these particles in conjunction with our ongoing remediation efforts," wrote Ron O'Brien, senior director of public relations.

"The remediation of the ditch is complete and restoration is currently underway as we continue to work closely with all of the appropriate government and regulatory parties, including the city of Sugar Land and the Texas Department of State Health Services (DSHS)."

"The health and safety of our employees and the community remains our top priority. Third-party radiological experts have determined that the particles do not present a threat to human health."

The work to remediate the Thermo Fisher facility is still ongoing. Neither the state nor the company could say how long the work will take to complete.

Thermo Fisher officials said they planned to shutter their Sugar Land facility prior to the incident and move operations to other facilities. Company officials did note the accidental release sped up the timetable for closing the facility.

DOWNLOAD: City of Sugar Land presentation