Environmental monitoring factors affecting on-site sampling of water and wastewater



1 Environmental monitoring water and wastewater sampling factors

1.1 Influence of natural environmental factors

It is inevitable for samples to be collected in the field environment to be affected by natural conditions, because nature is constantly changing, and the surrounding environment of samples is extremely unstable, which increases the difficulty of collecting samples of water and wastewater. For example, natural factors such as temperature change, rain and snow weather will have an impact on air pollutants. When pollutants fall with rain, on-site water and wastewater samples will be changed. In the monitoring of water quality, the collection of water samples for a certain river or section will be seriously affected by the surrounding environment of the river bank. There are pollution sources in the surrounding environment, which will not only lead to the pollution of the water environment, but also affect the monitoring results. At the same time, with the different regions and seasonal changes, part of the water sample monitoring is also affected by tidal changes. Therefore, before collecting water and wastewater samples, the staff should conduct field investigations in the areas where the samples need to be collected, make full preparations, ensure that the samples collected on the field are representative, and avoid the deviation of sample data affected by natural environmental factors.

1.2 Impact of instruments and devices

There are various types of instruments and equipment required in the field sampling process of water and wastewater. Due to their different functions, these equipment and instruments are responsible for completely different work, such as sampling equipment is responsible for sample collection, measuring equipment is responsible for field measurement, and storage equipment is responsible for sample storage. Once there is non-compliance with the equipment and instruments, it will also have a negative impact on the overall sampling results. In the process of adoption, monitoring equipment that should be relatively effective and standardized should be selected, so that the ideal water sample can be accurately collected at the compliant sampling position. Since the field sampling is carried out in real time, in order to ensure the effectiveness of later experiments and the accuracy of data analysis, it is particularly important to use standardized and effective instruments and equipment for sample collection, storage and transportation.

1.3 Influence of sampling personnel

When conducting on-site sampling of water and wastewater, relevant staff should first undergo corresponding sampling training and have corresponding sampling qualifications; Secondly, it should be carried out according to the corresponding prescribed standards and sampling plans. However, a problem exists at present is that most samplers do not realize the importance of sampling quality when sampling water and wastewater, which leads to these samplers do not follow the relevant plans and regulations when sampling water and wastewater. Of course, we did not pay enough attention to the selection of sampling points, sampling frequency of water samples, sampling containers, etc., and did not understand the specific sampling requirements of test items in advance, which also affected the on-site sampling quality of water and wastewater to a large extent.

1.4 Influence of sampling point and frequency

In the field sampling work of water and wastewater, the first thing to be scientifically confirmed is the point location. Since most of the water and wastewater sampling work sites are affected by the flow of water quality, sampling work at different locations and at different times will have a great impact on the final analysis results. How to minimize the influence of such factors is an important issue for the staff to face. The sampling frequency of water samples will also have a certain impact on the sampling work. If the sampling frequency is too high, the difference between samples is not obvious enough, which is not only helpful for the development of the experiment, but also affects the overall work efficiency. If the sampling frequency is too low, accurate experimental results can not be obtained, so that the field sampling work is meaningless.

2. Continuous improvement of environmental monitoring site sampling influencing factors

2.1 The environmental monitoring system is not perfect

The formal implementation of environmental monitoring methods in China is still in its infancy, and there are few relevant laws. If it comes to more complex environmental monitoring of water and wastewater, detailed procedures are not perfect, such as audit standards and documents without signed approval are prohibited. Secondly, the environmental detection system can not perfectly solve the actual problems, and the instructions issued can not be well implemented in time. Such a detection system has not fully realized its value, and even caused the loss of talents and financial waste, which is not conducive to the good development of environmental monitoring system. Environmental monitoring is a very complex work, with strong technical and scientific requirements, including data analysis, sample collection and other technical links. If you want to solve the imbalance in the quality of environmental monitoring data, you need to start from the relevant departments. The state needs to supervise the relevant departments at the technical level of environmental monitoring to reduce the occurrence of accidental mistakes in environmental monitoring by enterprises. In addition to the supervision of the technical level, it is necessary to strengthen the standard update of the equipment required for environmental monitoring and on-site sampling.

2.2 Reduce errors caused by equipment and instruments

The error of equipment and instruments often has incalculable consequences on the sampling results, so in order to ensure the sampling quality, the use of equipment and instruments must comply with the law to avoid problems caused by improper use of equipment. After the sampling of water and wastewater, the storage and sealing of samples must be carried out in accordance with the operating standards to avoid the negative impact of external factors on the samples. For some wastewater with special sampling requirements, the sampler and storage container should be washed with sampling water before the collection, and these special samples should be marked. And provide a suitable storage environment. Once there is a non-compliant part in the sample collection process, it is necessary to correct it in time and conduct supplementary collection, do not have a fluke mentality, and maintain a meticulous attitude to complete the work. In addition, during the sampling process, the relevant equipment and instruments should be properly protected, and the equipment should not be damaged due to operational errors. The equipment should also be isolated during transportation to avoid affecting the work efficiency due to damage.

2.3 Improve the quality awareness of staff

To reduce the influence of negative factors of on-site sampling of water and wastewater, it is necessary to improve the quality awareness of the staff, standardize the process of on-site sampling, and reduce the influence of accidental factors on the quality of on-site sampling. This requires that in the process of sampling work, staff in all aspects should strengthen the importance of the process, and work in accordance with uniform norms at each sampling point. In daily work, staff should be able to pay attention to improve their own work proficiency, in the sampling work can be timely and accurate to complete the relevant workflow. For on-site sampling work using law enforcement recorders, personnel, operations, equipment and real-time section environment should be taken into the video range at the same time, so as to facilitate later verification work.

2.4 Strengthen the monitoring of on-site sampling

In order to ensure the safety and accuracy of sampling, sampling personnel need to consider a variety of factors when conducting on-site sampling, and then determine the location of sampling samples. In addition, when taking water and wastewater, the staff should avoid some places with suspended materials, because these suspended materials will have a certain impact on the results of the selected samples. Of course, if the sampling personnel can not accurately select the sampling location, you can use the current technology GPS to select the sample location, so that with the help of high-tech will bring great convenience to the field sampling work. If workers use a boat to sample, they should be upstream to sample, so that they can protect against the impact of the sediment below. If the sampler samples at the same sampling site, it should choose a layered sampling method to select samples, so as to prevent the mutual disturbance between different levels. The unified operation before sampling should be to clean the container and instrument with water first, but for those with special requirements, it is not necessary to clean before sampling, and finally, it is necessary to make a record according to the relevant regulations.