NSSI operates a waste treatment, storage and disposal facility on approximately 5 acres in a light industrial area of Southeast Houston. The company receives wastes from a variety of offsite generators, treats the waste, and ships the residues to permitted offsite facilities for final disposal. The state of the art facilities are designed specifically for waste storage and treatment and include over 40,000 square feet of covered, high integrity epoxy coated concrete berm areas with an approved storage capacity of up to 4,000 drums. NSSI's 13 covered bulk liquid stainless steel storage tanks allow storage and treatment in excess of 55,000 gallons of waste liquids. Treatment facilities include an acid/base neutralization tank, slow speed mechanical shear shredder, glass lined Pfaudler reactors for oxidation/reduction reactions, a vacuum distillation unit, a dry waste compactor, stabilization system, and a continuous Mercury retort. Equipment may be configured as needed to provide single stage and multi-stage waste treatment systems. NSSI disposes of all solid and liquid effluents from the facility, with the exception of sanitary sewer wastes, as manifested wastes, to offsite permitted hazardous and non-hazardous, incineration and land disposal facilities.

NSSI is a fully permitted Part B hazardous waste TSDF and one of only three facilities in the U. S. providing storage and treatment of mixed hazardous/radioactive wastes. The facility receives waste from generators in all states and from foreign sources and is permitted to accept all radionuclide including special nuclear material and a full spectrum of EPA waste codes.
NSSI has been licensed to possess and use radioactive materials and process radioactive waste since 1971 and obtained its final part B permit for hazardous, non-hazardous, and mixed wastes on October 4, 1990. NSSI is permitted to receive and manage hazardous wastes , non-hazardous wastes, radioactive wastes, and mixed wastes under the regulatory authority of the Texas Commission for Environmental Quality (TCEQ).



NSSI was established in 1971 by Robert (Bob) Gallagher as a manufacturer of radioactive tracer materials and radioactive sealed sources. In conjunction with these manufacturing services, NSSI offered additional services and products including chemical and radioactive decontamination, leak testing, radiation instrument calibration, radiation safety training, and waste disposal. As the company grew hazardous waste disposal activities grew more specialized to encompass the treatment, storage, and disposal of radioactive, hazardous and non-hazardous, and mixed radioactive/hazardous wastes.

Subsequent to Bob Gallagher’s sudden passing in 2014 the company has come under the ownership and management of his son, Gary Gallagher. Dr. Gallagher has a stated goal of continuing to operate NSSI as a family business and to grow the company, to expand the business into new business lines, and to re-enter markets that the company has neglected in the past.


Tucked away in a quiet industrial area of Southeast Houston, NSSI is a state of the art facility specifically designed for waste storage and treatment. Occupying approximately five acres with over 40,000 square feet, we process over 700 tons of waste annually and the ability to process up to 4000 drums of waste, 3-4M gallons of aqueous hazardous waste, as well as handle approximately 1500 sealed sources. 

In business since 1971, our services support a diverse customer base in the government, industrial, radiopharmaceutical, and education sectors. NSSI currently holds two Texas Radioactive Materials Licenses (TDSHS, TCEQ) along with a Part B Permit which allows us to receive a broad spectrum of waste. We currently hold ongoing contracts with DOE, Schlumberger, North State Environmental.

We employ more than 40 to manage the facility.