Well Rehabilitation via the Ultrasonic Method and Evaluation of Its Effectiveness from the Pumping Test

The exploitation of groundwater reserves, especially for drinking purposes, is becoming increasingly important. This fact has created the need to maintain wells in the best possible functional condition. However, wells are subject to an ageing process during intensive use, which entails an increase in up-to-date resistances in the well itself and its immediate surroundings (the skin zone). This causes a decrease in the efficiency of the well (a decrease in the pumped quantity, a decrease in the specific yield, an increase of the drawdown in the well, and creation of the skin zone). The increased hydraulic gradient in the skin zone causes an increase in the inflow rate to the well, thereby inducing the movement of fine material towards the casing. This material can clog the well casing and injection ports, which is compounded by an increase in chemical and biological plugging of the skin zone. In cooperation with the company sonic technologies, GmbH. (Sailauf, Germany), an experimental ultrasonic technology-based well rehabilitation assembly was developed and successfully tested. This article describes the prototype development of the ultrasonic device, including its incorporation into the rehabilitation set and a demonstration of its pilot deployment in the MO-4 pumping well in Czech Republic with an evaluation of the rehabilitation effects using the authors’ software (Dtest_ULTRA). Based on visual inspection and the results of hydraulic and geophysical analysis, the high efficiency of the tested technology was demonstrated in virtually all monitored parameters, where an improvement in the range of 25–55% compared to the original condition was identified.

DIAGNOSTIC AND REHABILITATION OPPORTUNITIES OF DUAL-TASKS FOR BRAIN TRAUMA

Complex clinical, EEG and stabilographic examination revealed predominantly cognitive deficit in patients with moderate traumatic injury (mTBI) while dual tasks were performed. The EEG data demonstrated a decrease in the coherence for slow (delta-theta) rhythms in the frontal-temporal areas predominantly of the left hemisphere during cognitive tasks performance in patients. In healthy subjects an increase of EEG coherence for slow spectral bands was observed in these brain areas by contrast. An increase of EEG coherence was obtained for fast spectral bands - alpha2 and beta, predominantly at the right hemisphere while the motor components of the dual tasks were performed in healthy adults and patients. Rehabilitation course involving the use of dual-tasking contributed to a predominant reduction in cognitive deficits and an increase of EEG coherence at the frontal-temporal areas of the left hemisphere. So, dual-tasks may be used as diagnostic tool in patients after mTBI. Pilot studies allowed the proposed also rehabilitation effect of dualtasking in mTBI patients with primary and predominant restoration of cognitive functions and recovery of EEG coherence for slow spectral bands after rehabilitation course. So, our data allowed to propose that dual-tasks may be used as diagnostic as well rehabilitation tool in patients after mTB with the most sensitivity of the left hemisphere to traumatic effect and rehabilitation procedures.

A New Method for the Evaluation of Well Rehabilitation from the Early Portion of a Pumping Test

This study analyzes the unsteady groundwater flow to a real well (with wellbore storage and the skin effect) that fully penetrates the confined aquifer. The well is located within an infinite system, so the effect of boundaries is not considered. The Laplace-domain solution for a partial differential equation is used to describe the unsteady radial flow to a well. The real space solution is obtained by means of the numerical inversion of the Laplace transform using the Stehfest algorithm 368. When wellbore storage and the skin effect dominate pumping test data and testing is conducted for long enough, two semilogarithmic straight lines are normally obtained. The first straight line can be identified readily as the line of the maximum slope. The correlation of the dimensionless drawdown for the intersection time of this first straight line, with the log time axis as a function of the dimensionless wellbore storage and the skin factor, is shown. This paper presents a new method for evaluating the skin factor from the early portion of a pumping test. This method can be used to evaluate the skin factor when the well-known Cooper–Jacob semilogarithmic method cannot be used due to the second straight line not being achieved in the semilogarithmic graph drawdown vs. the log time. A field example is presented to evaluate the well rehabilitation in Veselí nad Lužnicí by means of the new correlation.

Development of a risk-based tool for groundwater well rehabilitation and replacement decisions

Groundwater wells are critical drinking water infrastructure elements that widely support basic system supply needs while also providing supply reliability, better water quality (in some cases), and comparatively lower operational costs. Well rehabilitation and replacement are thus an area where water utilities could benefit from rational decision support frameworks and quantitative tools that enable them to better navigate the complex trade-off relationship(s) that exist among a variety of environmental quality, public health, financial, regulatory, organizational, and technological dimensions. Consistent with these considerations, a business risk-based prioritization tool was developed for this study that augments/extends California Water Service (Cal Water)'s well rehabilitation and the replacement decision-making process. For this derivation, a business risk exposure methodology is combined with an analytical hierarchy process (AHP), with the AHP being utilized to determine the weights of the factors involved in the likelihood of failure and the consequence of failure calculation. It is expected that the new tool will assist in optimizing inspection and action plans and identify the wells requiring attention and/or additional work for water utilities.

Rehabilitation for Femoroacetabular Impingement: Conservative Care and Postoperative Practice

The understanding of femoroacetabular impingement (FAI) has increased over the past 10 years, with advancements in diagnosis and surgical techniques. Controversy remains regarding the ideal regimen of conservative care. Additionally, there is wide variety in postoperative clinical practice after hip arthroscopy. This review is a synthesis of resources on rehabilitation as a stand-alone treatment for FAI as well rehabilitation following surgery. Best evidence regarding conservative care is presented followed by postoperative debates on weight-bearing, range of motion, and physical therapy. In most cases, such as use of bracing and continuous passive motion, there are limited experimental studies to rely on. Higher quality evidence is required to support today's rehabilitation practices which are based mostly on theory and individual experience.

Status of marine turtle rehabilitation in Queensland

Rehabilitation of marine turtles in Queensland has multifaceted objectives. It treats individual animals, serves to educate the public, and contributes to conservation. We examined the outcome from rehabilitation, time in rehabilitation, and subsequent recapture and restranding rates of stranded marine turtles between 1996 and 2013 to determine if the benefits associated with this practice are cost-effective as a conservation tool. Of 13,854 marine turtles reported as stranded during this 18-year period, 5,022 of these turtles were stranded alive with the remainder verified as dead or of unknown condition. A total of 2,970 (59%) of these live strandings were transported to a rehabilitation facility. Overall, 1,173/2,970 (39%) turtles were released over 18 years, 101 of which were recaptured: 77 reported as restrandings (20 dead, 13 alive subsequently died, 11 alive subsequently euthanized, 33 alive) and 24 recaptured during normal marine turtle population monitoring or fishing activities. Of the turtles admitted to rehabilitation exhibiting signs of disease, 88% of them died, either unassisted or by euthanasia and 66% of turtles admitted for unknown causes of stranding died either unassisted or by euthanasia. All turtles recorded as having a buoyancy disorder with no other presenting problem or disorder recorded, were released alive. In Queensland, rehabilitation costs approximately $1,000 per animal per year admitted to a center, $2,583 per animal per year released, and $123,750 per animal per year for marine turtles which are presumably successfully returned to the functional population. This practice may not be economically viable in its present configuration, but may be more cost effective as a mobile response unit. Further there is certainly benefit giving individual turtles a chance at survival and educating the public in the perils facing marine turtles. As well, rehabilitation can provide insight into the diseases and environmental stressors causing stranding, arming researchers with information to mitigate negative impacts.

SOME EXPERIENCE OF REMOVING THE STUCK FLEXIBLE PIPE FROM THE WELL IN THE PROCESS OF SIDE HOLE DRILLING AND POSSIBLE WAYS OF SUCH TECHNOLOGY PERFECTION

This article subject of study is a method of retrieving the stuck flexible pipe during the inactive well rehabilitation in the process of string side-hole drilling under the abnormally low reservoir pressure conditions. It is mentioned that the most common are methods using a flexible pipe which are related predominantly with the bottomhole flushing to remove clay-sand bridges, thawing the hole to eliminate hydrate-paraffin deposits, the bottomhole zone treatment with chemical compositions. It is emphasized that there is not enough experience of side-hole drilling using a flexible pipe and practically no experience of fishing with the help of flexible pipe.

Investigations on the Performance of a Mechatronic System for Water Well Rehabilitation Using High Power Ultrasonics

In Denmark the public water supply is practically 100% served by groundwater abstracted from nearly 20.000 water wells. During time of operation the productivity from a well will often decrease drastically. This impaired performance is usually caused by well clogging. This clogging makes the well economically inefficient for the operator and therefore needs to be rehabilitated. This article examines the performance and evaluates the effectiveness of high power ultrasonics for water well rehabilitation. Special focus is drawn to the inconsistent efficiency of the currently, rarely used ultrasonic cleaning method caused by the specific varying conditions in water wells and correlated ultrasound intensity losses. The scope for improving the, in Denmark, rarely used ultrasonic cleaning method efficiency is investigated and suggestions for improvements based on a proof-of-concept prototype are given based on empirical- as well as theoretical studies.