Introduction
Trash pits are holes where prehistoric peoples placed their habitation refuse. During this excavation, 6 trash pits were discovered and denoted F1, F4, F28, F29, F30 and F31, respectively. Their locations are shown in the diagram below:

Trash pit F1
Trash pit F1 is located at the boundaries of pits E1, F1 and F2. It was damaged due to the uprooting of trees and only one-third of the trash pit remains on the east side. From north to south, the remaining length is 180 cm and from east to west the width is 100 cm. The original trash pit may have been oval in shape. The depth of the trash pit is approximately 60 cm, located at 90-150 cm below the surface. The upper layer is a mix of black-brown and yellowish-brown soil. It is very difficult to differentiate from the cultural layer next to the pit. However, there were larger concentrations of potsherds and stone tools in the trash pit while the cultural layer possessed large numbers of stones. From 130 cm below the surface, the cultural layer outside the trash pit ends and becomes dark yellowish-brown raw soil. Inside the trash pit, there is black-brown soil with clear boundaries. Although burial M4 and stone structure F19 lie adjacent to the northeast corner of trash pit F1, due to the damage caused during the removal of trees, it is not possible to determine their time relationship.

Trash pit F4
Trash pit F4 covers the east section of pits A2 and A3, the north section of B1, all of B2 and B3 and the west section of C2 and C3. It is oval in shape, measuring approximately 4 m in diameter from north to south and approximately 3 m from east to west. The orifice of the trash pit is at a depth of about 160 cm below the surface. At its deepest point, the trash pit is 210 cm below the surface. After breaking through the soil layer, there was a layer of gravel. On cross section, this trash pit is shaped like a shallow dish. It is deeper on the west side and shallower on the east side. Its maximum depth is about 50 cm. The black-brown soil layer contains abundant prehistoric remains such as potsherds and stone tools, as well as charcoal.  Between the raw soil layers of the trash pit and surrounding area, there is a permeation layer of approximately 10 cm in thickness. The color of the soil is between that of the trash pit and the raw soil. Almost no cultural remains were found in this layer.

The relationships between trash pit F4 and other features: 
1. The north end of trash pit F4 is connected to trash pit F31. The connecting point is compressed by gravel structure F6. Thus, gravel structure F6 is from a later time period than trash pits F4 and F31.
2. Trash pit F4 is compressed by gravel structure F3 and burial M2. Therefore, gravel structure F3 and burial M2 are from a later time period than trash pit F4. 
3. Trash pit 4 destroyed the erect slate structure F7 and gravel structure F8. Therefore, trash pit F4 is from a later time period than features F7 and F8.

Trash pits F30, F31
Trash pit F30 is mainly located within pit A4 with a small section extending to pits A3 and A5. The west end extends into the west boundary wall of pit A4. This feature was not completely excavated. The shape is a slightly curved trench roughly oriented in a northwest-southeast direction. It measures approximately 3 m in length and approximately 1 m in width. The orifice of the trash pit is at a depth of 150 cm below the surface. The bottom of the trash pit is at a depth of 210 cm below the surface into the gravel layer. The soil inside the trash pit is black-brown in color with a large amount of stone tools and potsherds.

The relationships between trash pit F30 and other features: 
1. Trash pit F30 is connected to the east side of trash pit F31. The accumulation is shallow and thin at the connecting point. Therefore, these are two distinct trash pits.
2. Most of trash pit F30 is compressed under stone structure F11. Therefore, stone structure F11 is from a later time period than trash pit F30. 　
Trash pit F31 is mainly located within pit B4 with a small section extending into B3. The shape is a nearly circular shallow dish with a diameter of approximately 2 m. The orifice of the trash pit is at a depth of about 150 cm below the surface. The base of the trash pit is at a depth of 180 cm below the surface. The soil inside the trash pit is black-brown in color with a large quantity of stone tools and potsherds.
The relationships between trash pit F31 and other features: 
1. Trash pit F31 is connected to the west end of trash pit F30.
2. The south side of trash pit F31 is compressed under gravel structure F6.
Cross-sectional view

Trash pits F28, F29
Trash pit F28 is mainly located within pits I1 and I2 with a small section extending into pits H1, H2, J1 and J2 and under stone structure F17. The orifice of the trash pit is at a depth of 120 cm below the surface. The depth of the trash pit is approximately 45 cm. At its deepest point, the trash pit is at 165 cm below the surface. The shape of the trash pit is an irregular oval with a diameter of approximately 300 cm from east to west and a diameter of approximately 240 cm from north to south. The soil is black-brown in color with potsherds and a large amount of gravel. Most 可黏合. Only stone tool fragments were found and these were not present in large numbers. A small amount of charcoal was also excavated. Along the northwest periphery of the trash pit were sandstone rocks in a manmade arrangement. There was also an accumulation of rocks from a collapse inside the trash pit. This might be evidence of a hearth.

Trash pit F29 is mainly located within pits J2 and J3, extending into the east wall of J3. The orifice of the trash pit is at a depth of approximately 120 cm below the surface. The base of the trash pit is at approximately 170 cm below the surface. The depth of the trash pit is about 50 cm. The part of the trash pit that was surveyed measures 115cm in length along an east-west orientation and 110 cm in diameter along a north-south orientation. The soil is black-brown in color. There were large quantities of slate pieces found under sandstone rocks. Some potsherds were also found. The nature of the feature is unclear.  Stone structure F15 was built on top of trash pit F29. Thus, trash pit F29 is from an earlier time period than stone structure F15.
 

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