Time filter

Source Type

Englewood, CO, United States

CH2M HILL is an American engineering company that provides consulting, design, construction, and operations services for corporations, and federal, state, and local governments. The firm's headquarters is in Meridian, an unincorporated area of Douglas County, Colorado in the Denver-Aurora Metropolitan Area. The postal designation of nearby Englewood is commonly listed as the company's location in corporate filings and local news accounts. As of December 2013 CH2M HILL had approximately 26,000 employees and 2013 revenues totaled $5.88 billion. The firm is employee-owned, with an internal stock market that operates buy/sell events quarterly. Wikipedia.

Senner R.,CH2M HILL
Environmental Impact Assessment Review | Year: 2011

Evaluating and comparing development alternatives with regard to sustainability is an important goal for comprehensive project appraisal. In the United States, this component has been largely missing from standard environmental impact assessment practice. Cumulative effects assessment provides a way to appraise the sustainability of project alternatives in terms of their probable contributions to long-term trends affecting the condition of valued environmental components. Sustainability metrics and predictors are being developed as criteria for rating systems and evaluation processes that are applied to community planning, building design, and transportation infrastructure. Increasing interest in adaptive management is also providing cost-effective solutions to optimizing safety and function throughout the long-term operation of a facility or infrastructure. Recent federal legislation is making it easier to integrate sustainability features into development alternatives through early, community-based planning. © 2011 Elsevier Inc. Source

Daigger G.T.,CH2M HILL
Water Science and Technology | Year: 2011

The modern age of wastewater treatment modelling began with publication of the International Water Association (IWA) Activated Sludge Model (ASM) No.1 and has advanced significantly since. Models are schematic representations of systems that are useful for analysis to support decision-making. The most appropriate model for a particular application often incorporates only those components essential for the particular analyses to be performed (i.e. the simplest model possible). Characteristics of effective models are presented, along with how wastewater modelling is integrated into the wastewater project life cycle. The desirable characteristics of wastewater treatment modelling platforms are then reviewed. Current developments of note in wastewater treatment modelling practice include estimates of greenhouse gas emissions, incorporating uncertainty into wastewater modelling and design practice, more fundamental modelling of process chemistry, and improved understanding of the degradability of wastewater constituents in different environments. Areas requiring greater emphasis include increased use of metabolic modelling, characterisation of the hydrodynamics of suspended and biofilm biological treatment processes, and the integration of biofilm and suspended growth process modelling. Wastewater treatment models must also interface with water and wastewater management software packages. While wastewater treatment modelling will continue to advance and make important contributions to practice, it must be remembered that these are complex systems which exhibit counter-intuitive behaviour (results differ from initial expectations) and multiple dynamic steady-states which can abruptly transition from one to another. © IWA Publishing 2011. Source

Ch2M Hill | Date: 2010-09-07

Methods and apparatuses are disclosed for optimizing oil and gas wells. Some embodiments may include optimizing a gas well based upon continuous measurements of the wells operating parameters, such as casing pressure draw down and/or line pressure surges. These continuous measurements of the wells parameters may be utilized to derive an empirical model of the wells behavior that is more accurate than conventional approaches with respect to the various stages of well production. In other words, by measuring the wells operating parameters continuously and measuring certain well parameters (like casing pressure draw down and/or surges in line pressure from opening the well), the empirical model derived therefrom may provide more accurate control of turn on criteria of the well than conventional approaches, such as during the mature production stage of production of the well.

Ch2M Hill | Date: 2011-04-15

A water or wastewater treatment system to reduce phosphorus or other pollutant concentrations in water or wastewater may include an optional primary treatment stage in fluid communication with a biological secondary treatment stage. The secondary treatment stage may, in turn, be fluidly connected with a tertiary treatment stage, which may include a chemical treatment portion for reducing phosphorus or other pollutants to desired levels. The precipitated phosphorus and other solids or sludge produced from the chemical treatment portion may be recycled upstream for reuse in the primary, secondary, and/or tertiary treatment stages. Such recycle may reduce the amount of added chemicals required in the tertiary treatment stage to phosphorus or other pollutants to desired amounts.

Disclosed herein is an insert device for semi-dynamic leach testing, the insert device including a support and an absorptive polymer disposed on the support, the insert device characterized by a sheet-like form having a first and second major side. The device is useful in testing of both radial and unidirectional leaching of organic compounds into water from solid samples.

Discover hidden collaborations