At the door of Siqingyuan, Gu Kaiwen was stopped by four young people, and the two sides were communicating.

Ma Zhiming organized a speech, "We are fourth-year students majoring in environment and microbiology at the University of Technology, and we designed a graduation project on the impact of landfills on the environment. So, we..."

Gu Kaiwen interrupted Ma Zhiming, "Let's change places." By the way, did you have lunch?"

Ma Zhiming shook his head.

"Let's go, I'll treat you to hot pot. Gu Kaiwen greeted.

A hot pot is worthless, even if Ma Zhiming is fooling, Gu Kaiwen will not feel fooled.

In the box of a hot pot restaurant on Beiyang Street, Gu Kaiwen first ordered his favorite dishes, and then handed the menu to Ma Zhiming, "You look at it, you can order whatever you like, and everyone orders what they like." ”

Ma Zhiming didn't have stage fright, he ordered two dishes, handed the menu to his classmates, and continued, "Master Zhai, do you think landfills have a big impact on the environment?"

"Nonsense!" Gu Kaiwen snorted.

Gu Kaiwen is engaged in natural environmental protection projects, although he is not a natural environmental protection major, but for some basic things, how can Gu Kaiwen not know?

The pollution of landfills to the environment is huge!

First, landfills take up a lot of space, and secondly, landfills can cause soil pollution in the landfill area, then groundwater pollution, followed by toxic and harmful gases and liquids that may be produced after the landfill is decomposed and fermented, which are all serious problems.

Ma Zhiming briefly described the dangers of landfills before continuing, "Our graduation project is mainly to investigate the impact of landfills on the environment. ”

"And then there is a result?" Gu Kaiwen asked.

Ma Zhiming nodded, "There is a result, and it is a very bad result!"

"Oh?" Gu Kaiwen asked with interest, "What is the bad result?"

Ma Zhiming took out a tablet from his backpack, unlocked it, clicked on a PDF file, and then handed it to Gu Kaiwen, motioning for Gu Kaiwen to look at it.

When Gu Kaiwen was looking at the PDF file, Ma Zhiming introduced it at the same time.

"The landfill we investigated was the Ansheng Landfill, which mainly accepts household waste from Nan'an and Zhongyu districts, with a daily processing capacity of 1,500 tons and a maximum capacity of nearly 3,000 tons, which was closed last year. Ma Zhiming introduced the basic situation.

Gu Kaiwen looked at the PDF file, and as Ma Zhiming said, the Ansheng landfill did close in 2016 because it was already filled with garbage and could not continue to fill more garbage.

"After the closure of the Ansheng landfill last year, the official patted the head on a project to turn the poisonous soil into a happy land and transform the landfill into an ecological park. Ma Zhiming said mockingly.

Gu Kaiwen also frowned.

Transforming a landfill into an ecological park, can this Nima really be?

What kind of outstanding people can make such a proposal?

Gu Kaiwen was very speechless!

"Master Zhai, have you seen the picture of the ecological park?" asked Ma Zhiming, in the PDF file, Ma Zhiming had already taken a picture of the ecological park.

Gu Kaiwen nodded, "The ecological park was done so quickly?"

"Heh!" Ma Zhiming sneered, "We have already investigated, this ecological park, just using the framework of the landfill, transplanting some landscape trees, and then leveling the ground to block the landfill, it is directly regarded as an ecological park." ”

Ma Zhiming continued, "Lord Zhai, you continue to look down!"

Gu Kaiwen viewed the PDF file according to his words.

"When we inspected the Ansheng landfill, we used ultrasonic detectors, and according to the information fed back by the ultrasonic waves, we found that this ecological park was an inferior tofu slag project, and the roof of the landfill was blocked, and there were cracks under the feedback of the ultrasonic detectors. Ma Zhiming explained the situation.

"In addition, based on the analysis of the results of the ultrasonic detectors, we found that there were underground cavities in the landfill. Ma Zhiming said in a serious tone.

Gu Kaiwen was puzzled, "Is the underground cavity a big trouble?"

Ma Zhiming nodded, "Yes! It is indeed a big trouble! We can't be sure whether the underground cavity is left by the landfill before it is filled, or whether it is caused by the corruption of underground garbage after the landfill is closed. ”

"Which situation is worse?" Gu Kaiwen didn't pretend to understand, he asked about the worse situation.

"The second. Ma Zhiming explained, "If it is the first case, then you only need to worry about the ground collapse caused by the capping of the tofu slag project." ”

Gu Kaiwen nodded slightly.

"But the second situation is even worse!" Ma Zhiming smiled bitterly, "According to our speculation, if it is the second case, that is, when the garbage is landfilled, the disposal of the garbage is not standardized, and perishable garbage is mixed in, which causes the perishable garbage to decay and ferment in the underground space, forming toxic and harmful liquids and gases that cannot be determined, and even gases that can be burned and exploded." ”

Ma Zhiming added, "If it is a combustible and explosive gas, that underground cavity is a time bomb, and none of us knows when it will go wrong." ”

Speaking of this, Ma Zhiming paused, "Master Zhai, you keep looking down, we have done more investigations. ”

Gu Kaiwen swiped down the PDF file.

Ma Zhiming said, "In order to determine the situation of the underground cavity, we used drones and infrared thermal detectors to detect, and we found that the temperature of the underground cavity area is significantly higher than that of other areas. ”

Gu Kaiwen looked at the infrared thermal imaging picture, just like the situation introduced by Ma Zhiming, the temperature in the underground cavity area was higher.

"What does higher temperature mean?" asked Gu Kaiwen.

Ma Zhiming explained, "There are two reasons for the higher temperatures. First, there is still a chemical reaction in this underground cavity area, and it is very likely that the garbage is still decomposing, and the second reason is that the underground cavity area has accumulated greenhouse gases, probably carbon dioxide, and methane, as well as some other toxic and harmful gases. ”

Ma Zhiming added, "If methane occupies more, then this underground cavity area will be very dangerous!"

"So about the underground cavity, you are more inclined to the second possibility, it is caused by garbage corruption, right?" Gu Kaiwen asked rhetorically.

Ma Zhiming nodded without hesitation, "Yes, we are more inclined to this possibility, and the image information obtained by the infrared thermal detector also supports our guess." ”

"Then how do you need me to help you?" Gu Kaiwen looked at Ma Zhiming and asked.

。 Reading at zero o'clock