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Envirostat Inc.

Fort Collins, CO, United States

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Esbensen K.H.,Geological Survey of Denmark | Esbensen K.H.,University of Aalborg | Ramsey C.A.,Envirostat Inc.
Journal of AOAC International | Year: 2015

Quality control (QC) is a systematic approach for estimating and minimizing significant error contributions to the measurement uncertainty from the full sampling and analysis process. Many types of QC measures can be implemented; the three dealt with here are primary sampling reproducibility, sample processing reproducibility, and contamination. Sampling processes can be subject to QC by applying a replication experiment, used either from the top by replication of the entire sampling/ preparation/analysis process, or in a hierarchical fashion successively at each subsequent sampling stage. The analytical repeatability is necessarily always included in either alternative. The replication experiment results in a quality index, the Relative Sampling Variability, which is used to assess the total error associated with the full field-to-analysis pathway. Contamination can occur at essentially all locations in the sampling regimen in the food/feed realm, affecting sample containers, sampling tools, sample processing equipment, environmental conditions, and sampling personnel. QC events to determine contamination should always be included where appropriate, but is of most concern for low concentration and/or volatile analytes. It is also of key importance in the development of new sampling protocols or carried-over protocols intended for use on new types of materials/lots than the ones for which they were originally developed. We here establish a first practical framework for QC as applied to the sampling context.


Walsh M.R.,U.S. Army | Walsh M.E.,U.S. Army | Taylor S.,U.S. Army | Ramsey C.A.,Envirostat Inc. | And 5 more authors.
Propellants, Explosives, Pyrotechnics | Year: 2013

Insensitive high explosives are being used in military munitions to counteract unintended detonations during storage and transportation. These formulations contain compounds such as 2,4-dinitroanisole (DNAN) and 3-nitro-1,2,4-triazol-5-one (NTO), which are less sensitive to shock and heat than conventional explosives. We conducted a series of four tests on snow-covered ice utilizing 60-mm mortar cartridges filled with 358g of PAX-21, a mixture of RDX, DNAN, and ammonium perchlorate. Rounds were detonated high- and low-order using a fuze simulator to initiate detonation. Blow-in-place (BIP) operations were conducted on fuzed rounds using an external donor charge or a shaped-charge initiator. Results indicate that 0.001 % of the original mass of RDX and DNAN were deposited during high-order detonations, but up to 28 % of the perchlorate remained. For the donor block BIPs, 1 % of the RDX and DNAN remained. Residues masses for these operations were significantly higher than for conventional munitions. Low-order detonations deposited 10-15 % of their original explosive filler in friable chunks up to 5.2g in mass. Shaped-charge BIPs scattered 15 % of the filler and produced chunks up to 15g. Ammonium perchlorate residue masses were extremely high because of the presence of large AP crystals, up to 400μm in the recovered particles. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Walsh M.R.,U.S. Army | Walsh M.E.,U.S. Army | Ramsey C.A.,Envirostat Inc. | Brochu S.,Defence Research and Development Canada | And 2 more authors.
Journal of Hazardous Materials | Year: 2013

The insensitive high-explosive PAX-21 was the first of its kind fielded in an artillery munition by the United States military. This formulation contains three main components: RDX, dinitroanisole, and ammonium perchlorate (AP). In March 2012, detonation tests were conducted on PAX-21 60. mm mortar rounds to determine the energetic residues resulting from high-order and blow-in-place (BIP) detonations. Post-detonation residues were sampled and analyzed for the three main PAX-21 components. Concentrations of RDX and dinitroanisole in the samples were quite low, less than 0.1% of the munitions' original organic explosive filler mass, indicating high order or near high order detonations. However, disproportionately high concentrations of AP occurred in all residues. The residues averaged 15% of the original AP following high-order detonations and 38% of the original AP mass following the BIP operations. There was no correlation between AP residues and the RDX and dinitroanisole. Perchlorate readily leached from the detonation residues, with over 99% contained in the aqueous portion of the samples. Use of these rounds will result in billions of liters of water contaminated above drinking water perchlorate limits. As a result of this research, PAX-21 mortar rounds are currently restricted from use on US training ranges. © 2013.


Walsh M.R.,U.S. Army | Walsh M.E.,U.S. Army | Ramsey C.A.,Envirostat Inc. | Thiboutot S.,Defence Research and Development Canada | And 3 more authors.
Propellants, Explosives, Pyrotechnics | Year: 2014

The development of insensitive munitions by NATO countries is an ongoing effort. Less-sensitive ingredients in both explosives and propellants will ensure the protection of deployed troops against an unwanted reaction to an external stimulus on the munitions stockpile. In the US Army, current efforts are directed towards the development of melt cast insensitive explosive formulations. Various formulations, mainly based on DNAN and NTO, have been developed and are now being fielded. Our research goal is to measure the deposition rate of energetics compounds from various insensitive munitions detonation scenarios. Our hypothesis is that the relative insensitiveness of these formulations leads to slightly higher deposition rates than conventional explosive formulations. This paper describes detonation residues research on mortar rounds containing IMX-104 explosive. Analyses indicate that high-order detonation residues are slightly greater for this formulation than for conventional munitions. However, blow-in-place detonations (BIPs) resulted in much higher residues deposition, indicating that a larger donor charge is required for efficient detonation. The highly soluble compound NTO was particularly problematic, with BIP deposition approaching 95% of the original load. Toxicological studies of NTO are not finalized, leaving considerable uncertainty regarding the feasibility of approving these rounds for distribution. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Walsh M.R.,United States Cold Regions Research and Engineering Laboratory | Walsh M.E.,United States Cold Regions Research and Engineering Laboratory | Ramsey C.A.,Envirostat Inc.
Water, Air, and Soil Pollution | Year: 2012

Energetic residues from military live-fire training will accumulate on ranges and lead to the contamination of soil and water. Characterizing surface soils for energetic contamination has been conducted extensively in the past. However, deriving mass deposition rates on soils for specific munition-related activities, necessary for determining the cumulative impact of these activities and developing range sustainability models, has been problematic. Factors include determining the energetic residues deposition area, discriminating current deposition from previous activities, separating the residues from the collection matrix, and processing the samples. To circumvent these problems, methods were developed for sampling energetic residues on clean snow surfaces. At firing points, a clean snow surface allows the collection of propellant residues from a known quantity and type of munition. Explosives residues from projectile detonations can be sampled from clean snow- and ice-covered surfaces in active impact areas. Sampling protocols have been optimized and quality assurance procedures have been developed during years of research on munition residues deposition rates. These methods are currently being used in the US, Canada, and Norway for both energetics and metal contaminants with other applications under consideration. This paper describes the current sampling protocol for clean snow surfaces and presents examples of its application. © 2012 Springer Science+Business Media (outside the USA).


Ramsey C.A.,Envirostat Inc.
Journal of AOAC International | Year: 2015

Sampling agricultural soils for contaminants is relatively new. Existing standard sampling protocols used for the evaluation of soil nutrients are likely insufficient for contaminants. The main reasons are the very low analyte levels and differences in heterogeneity between nutrients and contaminants. To evaluate the adequacy of existing sampling protocols or to develop new protocols, a systematic scientific approach is needed. This approach begins with the development of the Sample Quality Criteria followed by a realistic understanding of the properties of the material to be sampled, most notably its heterogeneity. The Sample Quality Criteria and material properties are inputs into the Theory of Sampling. With these inputs, the Theory of Sampling can be used to determine the specifics of the sampling protocol (e.g., mass, number of increments, tool selection) that must be implemented to control error to reliably estimate the concentration of the analyte(s) of interest. Development of sampling protocols in this manner will ensure sample representativeness and therefore improve data equivalency among various parties involved. This is the only way to provide a sound technical basis for defensible decision making to ensure increased safety of food and feed, specifically with respect to contaminants in agricultural soils.


Ramsey C.A.,Envirostat Inc. | Wagner C.,Ostpreussenring 46
Journal of AOAC International | Year: 2015

The concept of Sample Quality Criteria (SQC) is the initial step in the scientific approach to representative sampling. It includes the establishment of sampling objectives, Decision Unit (DU), and confidence. Once fully defined, these criteria serve as input, in addition to material properties, to the Theory of Sampling for developing a representative sampling protocol. The first component of the SQC establishes these questions: What is the analyte(s) of concern? What is the concentration level of interest of the analyte(s)? How will inference(s) be made from the analytical data to the DU? The second component of the SQC establishes the DU, i.e., the scale at which decisions are to be made. On a large scale, a DU could be a ship or rail car; examples for small-scale DUs are individual beans, seeds, or kernels. A well-defined DU is critical because it defines the spatial and temporal boundaries of sample collection. SQC are not limited to a single DU; they can also include multiple DUs. The third SQC component, the confidence, establishes the desired probability that a correct inference (decision) can be made. The confidence level should typically correlate to the potential consequences of an incorrect decision (e.g., health or economic). The magnitude of combined errors in the sampling, sample processing and analytical protocols determines the likelihood of an incorrect decision. Thus, controlling error to a greater extent increases the probability of a correct decision. The required confidence level directly affects the sampling effort and QC measures.


Ramsey C.A.,Envirostat Inc.
Journal of AOAC International | Year: 2015

Sampling water is no different than sampling any other media. It starts with the development of Sample Quality Criteria, understanding of material properties, then application of the Theory of Sampling. The main difference with sampling water as opposed to solids is the material properties. This paper addresses some of the material properties and consequences of those properties for the development of the sampling protocols. Two properties that must be addressed for water are the temporal nature and the inclusion of suspended solids. Examples are provided for three specific water sampling scenarios which may have application to other water sampling scenarios.


Wagner C.,Ostpreussenring 46 | Ramsey C.A.,Envirostat Inc.
Journal of AOAC International | Year: 2015

The lack of a sound scientific sampling approach results in unknown data quality and ultimately indefensible decisions. Sampling Quality Criteria (SQC) need to be correctly defined and made explicit to ensure that sampling protocols are representative and fit-for-purpose. The systematic approach to representative sampling framework is the only approach that can ensure development of reliable and representative sampling protocols under all circumstances for all application scenarios.


Ramsey C.A.,Envirostat Inc.
Journal of AOAC International | Year: 2015

The goal of sampling is to take a small portion of a target material for analysis instead of collecting all the material. If sampling is done following certain principles, then inference can be made from analytical results of the portion taken back to the entire target material (Decision Unit). There are different sampling strategies that are dependent on the properties of the material being sampled as well as different methods for making inferences from analytical results to the Decision Unit (DU). A thorough understanding of material properties and methods for inference is therefore critical for the development of proper sampling protocols. This paper addresses inferences from analytical test results to DUs and the implications to the development of a sampling protocol.

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