Abstract: A real time differential asphalt pavement quality sensor of the present invention is adapted to measure asphalt density in real time using a differential approach. Two sensors, one in the front of a roller and another behind the roller, measure reflected signals from the asphalt. The difference between the reflected signals provides an indication of the optimal compaction and density of the asphalt pavement. The invention looks at the change in variance over successive passes to determine when the optimal level of compaction has been reached.

Abstract: A system for sampling and analyzing a material located at a hazardous site. A laser located remote from the hazardous site is connected to an optical fiber, which directs laser radiation proximate the material at the hazardous site. The laser radiation abates a sample of the material. An inductively coupled plasma is located remotely from the material. An aerosol transport system carries the ablated particles to a plasma, where they are dissociated, atomized and excited to provide characteristic optical reduction of the elemental constituents of the sample. An optical spectrometer is located remotely from the site. A second optical fiber is connected to the optical spectrometer at one end and the plasma source at the other end to carry the optical radiation from the plasma source to the spectrometer.

Abstract: A subsurface sampler including a cylindrical casing with portholes to provide access below ground to sample potentially hazardous substances without contaminating investigative probes that are inserted into the interior cavity of the casing. The sampler has an inner sleeve that seals the portholes on the casing during the insertion operation. After the casing is inserted into the ground, the inner sleeve is rotated such that the windows on the sleeve and casing line up exposing the soil to a variety of investigative probes. A tab or wiper is attached to the inner sleeve to clear soil blocking the portholes in the casing and to cut through the "smear" zone immediately along side of the outer surface of the casing. Once the sampler casing is in the ground and portholes are open, a sampling probe is inserted into the interior cavity of the casing following a track or guide system.