Although the main HPP/RPP structure had been buried in Piketon, the so-called compressor building remained on the property of INCO in Huntington, WV.

The survey occurred after Oak Ridge National Laboratory (ORNL)  recommended a “detailed formal survey” for determination of the source of elevated gamma readings in the compressor building and elevator shaft, external gamma radiation levels throughout the site, radionuclide concentrations in subsurface soil, concentration levels on surfaces inside the compressor building, and nickel concentrations in surface and subsurface soil.

According to the results, alpha, beta and gamma test were undertaken for various radionuclides. They included Uranium 235, Uranium 238, associated decay products,  Ra-226, Ra-228, Th-230, Th-228, Pa-231, Ac-227, I-125, I-129, Th-232, Sr-90, Ra-223, Ra-224, II-232, I-126, I-131, I-133, and “Beta-gamma emitters” (nuclides with decay modes other than alpha emission or spontaneous fission except Sr-90).

The table uses a “dpm” term which means disintegrations per minute  or the rate of emission by radioactive material as determined by correcting the counts per minute observed by an appropriate detector for background, efficiency, and geometric factors associated with the instrumentation.

The amount of removable radioactive material is measured per 100 cm squared of surface area determined by wiping that area with a dry filter or soft absorbent paper, applying moderate pressure, and assessing the amount of radioactive material on the wipe with an appropriate instrument of know efficiency.

In 1994, Mayor Jean Dean received a letter from AEC/DOE stating that the former uranium and nickel producing site had been cleared for “unrestricted”  use based on Guideline for Decontamination of Facilities and Equipment Prior to Release for Unrestricted Use or Termination of Licenses for Byproduct, Source, or Special Nuclear Material” under the U.S. Nuclear Regulatory Commission (NRC).

“Comparison of the compressor building survey results with guideline for natural uranium and its decay products indicates that the measured levels are BELOW those guidelines for transferrable and total alpha and beta-gamma contamination. The external beta-gamma radiation dose rates at 1 cm from the building surfaces are also below the NRC guidelines.”

A table (pictured and downloadable by PDF) indicated the guidelines with which the West Virginia site was compared in terms of  less than an “average” and a “maximum” radiation level.

Under the table , the average and maximum radiation levels associated with surface contamination from beta-gamma emitters should not exceed 0.2 mrad/hr at 1 cm and 1.0 mrad/hr at 1 cm, respectively, measured through not more than seven milligrams per square centimeter of total absorber.

The readings for the Uranium and associated decay products averaged less than 5,000 d.p.m. a/100 cm squared. The maximum was less than 15,000 d.p.m. a/100 cm squared.

For transuranics (i.e. radium, iodine) the average was less than 100 d.p.m./100 cm squared and the maximum less than 3,000 d.p.m./100 cm squared. For the third category (Sr-90, U-232, Th-nai), the average was less than 1,000 d.p.m./100 cm squared and the maximum less than 3,000 d.p.m./100 cm squared. Beta gamma emitters averaged less than 5,000 d.p.m. By/100 cm squared.

http://www.eecap.org/Covered_Facilities/West_Virginia/Huntington.htm

http://www.eecap.org/PDF_Files/W_Virginia/Radiological_Assessment--1981.pdf

Contamination Limits Explained