Hydraulic fracturing wastewaters discharged to surface water have led to elevated bromide and iodide levels, as well as enhanced formation of brominated trihalomethanes, haloacetic acids, haloacetonitriles, and iodo-trihalomethanes at downstream drinking water treatment plants, in chlorinated effluent from wastewater treatment plants, and in controlled laboratory studies. This enhanced formation of brominated and iodinated disinfection byproducts (DBPs) raises concerns regarding human health, because they are much more toxic than chlorinated DBPs. This study represents the first nontarget, comprehensive analysis of iodinated DBPs formed in chloraminated produced waters associated with hydraulic fracturing of shale and conventional gas formations. Fifty-six iodo-phenolics were identified, comprising three homologous series of mono-, di-, and tri-iodinated phenols, along with two new classes of DBPs: iodomethylphenols and iododimethylphenols. Four iodo-phenolics (2-iodophenol, 4-iodophenol, 2,4,6-triiodophenol, and 4-iodo-2-methylphenol) were investigated for mammalian cell cytotoxicity. All were cytotoxic, especially 2,4,6-triiodophenol, which was more cytotoxic than all trihalomethanes and most haloacetic acids. In addition, geogenic organic compounds present in the oil and gas produced waters, including methylphenol and dimethylphenol, were found to be potential precursors to these iodo-DBPs.

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ABSTRACT. The Oak Ridges Moraine (ORM) case is unique in that it represents a social innovation in Canadian, if not North American, ecosystem-based land-use planning. A social innovation is an initiative, product, process, or program that profoundly changes the basic routines, resources, and authority flows or beliefs of any social system. Successful social innovations have durability and broad impact. We interpret the narrative of the ORM conservation process to explore the utility of an emerging social innovation conceptual model, the 'vision as social interaction' framework using resilience thinking and the role of vision in social change within complex social-ecological systems. Qualitative data from two interrelated studies of the moraine were reinterpreted and include 38 in-depth, semistructured interviews conducted between 2004-2006, as well as extensive participant observation at over 50 moraine conservation meetings, workshops, and events. The results of our study indicate that emerging model of social innovation can be linked with other models of 'radical change' such as those that employ concepts like 'policy windows' to describe opportunities for continued innovation once an initiative has reached the routinized phase. Just as with the panarchy cycle, when a social-ecological system reaches the conservation phase, the system has a propensity to collapse and reorganize. Rather than seeing this as the end of an initiative or program, such as is the case with the ORM, stakeholders can see it as an opportunity for reorganization with newly released resources and new opportunities.

Introduction of oil and gas extraction wastewaters (OGWs) to surface water leads to elevated halide levels from geogenic bromide and iodide, as well as enhanced formation of brominated and iodinated disinfection byproducts (DBPs) when treated. OGWs contain high levels of chemical additives used to optimize extraction activities, such as surfactants, which have the potential to serve as organic DBP precursors in OGW-impacted water sources. We report the first identification of olefin sulfonate surfactant-derived DBPs from laboratory-disinfected gas extraction wastewater. Over 300 sulfur-containing DBPs, with 43 unique molecular formulas, were found by high-resolution mass spectrometry, following bench-scale chlor­(am)­ination. DBPs consisted of mostly brominated species, including bromohydrin sulfonates, dihalo-bromosulfonates, and bromosultone sulfonates, with chlorinated/iodinated analogues formed to a lesser extent. Disinfection of a commercial C12-olefin sulfonate surfactant mixture revealed dodecene sulfonate as a likely precursor for most detected DBPs; disulfur-containing DBPs, like bromosultone sulfonate and bromohydrin disulfonate, originated from olefin disulfonate species, present as side-products of olefin sulfonate production. Disinfection of wastewaters increased mammalian cytotoxicity several orders of magnitude, with chloraminated water being more toxic. This finding is important to OGW-impacted source waters because drinking water plants with high-bromide source waters may switch to chloramination to meet DBP regulations.

This paper examines the role of drill solids in causing formation and completion damage in horizontal openhole completions. Drill solids are routinely kept to a minimum in drilling fluids, mainly to improve drilling properties. However, these drill solids, even at low concentrations, represent a significant source of insoluble particulates that become incorporated in the drill-in fluid filtercake. Not only is the potential for formation damage greater, but these filtercakes laden with insoluble drill solids can be deposited on screens resulting in reduced productivity through screen plugging. The objective of this paper is to illustrate the effect of drill solids contained in drill-in fluids on formation damage and well screen plugging and to emphasize the importance of minimizing solids, not only to maintain the desired drill fluid rheology, but also to effect better filtercake cleanup. New laboratory test methods have been used to study formation damage in a 2-foot long horizontal wellbore model incorporating dynamic filtercake deposition on natural and synthetic core material. The model measures formation damage in radial flow. Formation damage tests with drill solids were performed for both water based and synthetic based drill-in fluids. Testing was also performed to simulate prepacked screen damage using a variety of commercially available drill-in fluids and common resin-coated gravel sizes. Results of these tests with laboratory-prepared fluids have been compared against the performance of field fluids and will eventually be correlated with field well performance. Background The use of horizontal wells to maximize recovery of oil and gas has become commonplace. However, operators frequently find horizontal wells do not provide the expected productivity after completion. While cased hole completions exploit perforation techniques to bypass the zone of formation damage caused by drilling, the openhole completions commonly used in horizontal wells do not provide a means of bypassing this damage. Previous work has discussed formation damage caused by drill-in fluids. Often, these studies have concluded that formation damage is caused by solids invasion into the rock or from damage caused by incompatible fluid filtrate. Some investigators have presented evidence that DIF filtercakes did not penetrate into rock matrices. Fraser's study showed ESEM photo images of different types of DIF filtercakes tightly compacted onto formation rock surfaces. He found very little filtercake invasion in the rock matrix. Burnham and Browne have discussed the concept of "lift off" pressure that can be used characterize the behavior of DIF filtercake on formation rock. Their studies suggest that "formation damage" can be caused by too "tight" a filtercake on rock surface. P. 749

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One of the petroleum industry's goals is to reduce the environmental impact during oil and gas drilling operations. To achieve this, a number of environmentally friendly drilling (EFD) technologies have been developed to varying degrees but few have been integrated into a field demonstrable drilling system compatible with ecologically sensitive areas. This paper proposes a technology evaluation method based on systems analysis that can be used for integrating current and new EFD technologies into an optimal EFD system. An optimisation scheme is suggested based on a combination of multi-attribute utility theory and exhaustively enumerating all possible technology combinations to provide a quantitative rationale and suggest the best set of systems for a given site. An application of the proposed approach is described by conducting a case study in Green Lake at McFaddin, TX. The main purpose of this case study is to test the proposed technology evaluation protocol in a real site and then to refine the protocol. This paper describes the results of the case study, which provided a more logical and comprehensive approach that maximised the economic and environmental goals of both the landowner and the oil company.

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