This article provides a review of the routine methods currently utilized for total naphthenic acid analyses. There is a growing need to develop chemical methods that can selectively distinguish compounds found within industrially derived oil sands process affected waters (OSPW) from those derived from the natural weathering of oil sands deposits. Attention is thus given to the characterization of other OSPW components such as oil sands polar organic compounds, PAHs, and heavy metals along with characterization of chemical additives such as polyacrylamide polymers and trace levels of boron species. Environmental samples discussed cover the following matrices: OSPW containments, on-lease interceptor well systems, on- and off-lease groundwater, and river and lake surface waters. There are diverse ranges of methods available for analyses of total naphthenic acids. However, there is a need for inter-laboratory studies to compare their accuracy and precision for routine analyses. Recent advances in high- and medium-resolution mass spectrometry, concomitant with comprehensive mass spectrometry techniques following multi-dimensional chromatography or ion-mobility separations, have allowed for the speciation of monocarboxylic naphthenic acids along with a wide range of other species including humics. The distributions of oil sands polar organic compounds, particularly the sulphur containing species (i.e., OxS and OxS2) may allow for distinguishing sources of OSPW. The ratios of oxygen- (i.e., Ox) and nitrogen-containing species (i.e., NOx, and N2Ox) are useful for differentiating organic components derived from OSPW from natural components found within receiving waters. Synchronous fluorescence spectroscopy also provides a powerful screening technique capable of quickly detecting the presence of aromatic organic acids contained within oil sands naphthenic acid mixtures. Synchronous fluorescence spectroscopy provides diagnostic profiles for OSPW and potentially impacted groundwater that can be compared against reference groundwater and surface water samples. Novel applications of X-ray absorption near edge spectroscopy (XANES) are emerging for speciation of sulphur-containing species (both organic and inorganic components) as well as industrially derived boron-containing species. There is strong potential for an environmental forensics application of XANES for chemical fingerprinting of weathered sulphur-containing species and industrial additives in OSPW.

SYNOPSISDried samples of polyacrylamide in an He atmosphere have been subjected to thermogravimetric analysis in the 30-600°C range, and the evolved gases were monitored by FTIR. Water, ammonia, and small quantities of carbon dioxide are released in the first stages of decomposition (22O-34O0C), where the polymer chains remain intact and the reaction occurs on the pendant amide groups. In the second stage of decomposition ( 340-440°C), the majority of the weight loss occurs, and main chain breakdown occurs, releasing carbon dioxide, water, nitrile compounds, and imides. Trapping of the gases in this stage and analysis by GC-FTIR and GC-MS reveals the presence of more than 20 decomposition products, and confirms that a large proportion of these can be assigned to glutarimide and its substituted analogs. Imidization and dehydration reactions on the amide groups, as well as free radical breakdown of the main chains, with inter-and intramolecular hydrogen transfer, can account for many of the products of the decomposition. 0 1993 John Wiley & Sons, Inc.ature, thermal stability, and mechanism of decomposition.2-'2 PAM is amorphous with a glass transition temperature ( T,) of 184°C.6 When heated thermogravimetrically at rates of 5-20°C min-' , undried samples of this polymer decompose in at least three stages. The first stage (20-220°C) corresponds to loss of bound H20, and the second (220-340°C) to loss of NH3 by imidization (intra-and intermolecular) and H 2 0 by dehydration. The third region ( >34OoC) represents substantial weight loss, and is normally attributed to main chain breakdown.Evolved gas analysis can yield substantial insight into the mechanism of thermal decomposition. Maurer and Harvey' used thermogravimetry-mass spectrometry (TG-MS) on PAM to identify NH3, H20, and COZ as gases that evolve during decomposition. Leung, Axelson, and Van Dyke2 used MS to determine the presence of several evolved gases ( NH3, H20, CO,, N2, and CO) when samples of PAM were heated isothermally at various elevated temperatures. Toth et a1.l' used TG-MS to identify H20, NH3, CO, C02, HCN, and some low molecular 1807

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