Abstract: Apparatus and methods for water treatment are described, particularly for the simultaneous removal of nitrate, perchlorate, and other organic contaminates from contaminated water using a membrane biofilm reactor (MBfR).

Abstract: Apparatus and methods for water treatment are described, particularly for the simultaneous removal of nitrate, perchlorate, and other organic contaminates from contaminated water using a membrane biofilm reactor (MBfR).

Abstract: Apparatus and methods for water treatment are described, particularly for the simultaneous removal of nitrate, perchlorate, and other organic contaminates from contaminated water using a membrane biofilm reactor (MBfR).

Abstract: Compositions and methods for the removal of selenium species from water containing high-salt concentrations and/or petroleum contaminants are described. The compositions and methods use a selenium-reducing microorganism adapted to adverse environments.

Abstract: A method for inhibiting formation of hexavalent chromium during oxidative remediation of a contaminated site containing trivalent chromium is described. The method comprises introducing ozone at a first point to the contaminated site, where the ozone is introduced at a first frequency and for a first period of time, and introducing hydrogen peroxide to the contaminated site, where the hydrogen peroxide is introduced at a second frequency and for a second period of time. The first and second frequencies and first and second periods of time are selected to inhibit formation of hexavalent chromium within the site of remediation.

Abstract: Innovative methods and systems for the removal and destruction of contaminants present in reclaimed or other waste water are described.

Abstract: A system and method for the in-situ removal or remediation of contaminants in a soil formation containing a subsurface groundwater aquifer, the method comprising the steps of: injecting a first oxidant into the aquifer at an injection point to create a volume of influence of the first oxidant in the aquifer thereby treating the contaminants contained within the volume of influence; and injecting a compressed gas into the aquifer to increase the size of the volume of influence of the first oxidant. The injection of the compressed gas into the aquifer can also force the groundwater in the aquifer away from the injection point into a surrounding area to transport the first oxidant into the surrounding area thereby extracting contaminants from soil adjacent to the surrounding area.

Abstract: A system and method for the in-situ removal or remediation of contaminants in a soil formation containing a subsurface groundwater aquifer, the method comprising the steps of: injecting a first oxidant into the aquifer at an injection point to create a volume of influence of the first oxidant in the aquifer thereby treating the contaminants contained within the volume of influence; and injecting a compressed gas into the aquifer to increase the size of the volume of influence of the first oxidant. The injection of the compressed gas into the aquifer can also force the groundwater in the aquifer away from the injection point into a surrounding area to transport the first oxidant into the surrounding area thereby extracting contaminants from soil adjacent to the surrounding area.

Abstract: Oxidizable contaminants in water are destroyed rapidly and efficiently by exposing the water to oxidizing conditions under pressure. Specifically, a single dose of hydrogen peroxide may be injected into the water, followed by the repeated injection and mixing of low doses of ozone. In each such high intensity mixing/reaction stage, ozone is injected at a pressure, velocity, and direction approximately matching that of the contaminated water flow. High intensity mixing under pressure facilitates rapid and complete oxidation of the contaminants with minimal stripping of volatile contaminants and waste of undissolved ozone. Residual ozone levels after high intensity mixing may be carefully monitored and minimized by adjusting the injection of hydrogen peroxide and ozone in order to suppress the formation of bromate. Additional contaminants may be removed by passing the treated water through activated carbon beds.

Abstract: A method for detecting the end point of etching wafers and the like by reflective means. Typically, a detected reflectance signal will have a threshold level representing a lack of substantial etching, a dip in the threshold level representing the commencement of etching and an inflection level representing a maximum rate of light amplitude change. The present method involves subtracting the inflection level from the threshold level and taking a predetermined fraction of the resultant level to define a second threshold level further in the etch cycle which anticipates the end of the cycle. By observational experience, the predetermined fraction can be determined. As soon as the second threshold level is reached, brakes are applied to the etching process so that etching will cease shortly after the predetermined level has been identified.