1. Is there something wrong with the leaching field , which is 20 years old? 2. There is icky stuff in the yard over the leaching field , and it stinks. 3. A . The leaching field is saturated and slow-draining. 4. A septic tank is a separate container, with pipes leading to a specific leaching field . 5. More important, I have discovered little subtle depressions in the lawn over the leaching field . 6. The liquid, or effluent, gets spread out in an underground leaching field via perforated pipes. 7. And with a properly-working septic you will have a fairly clear effluent going into the leaching field . 8. The 60-minute percolation rate requires twice as big a leaching field as the 30-minute percolation rate, he said. 9. Q . I just moved into a house that has a septic system, with the usual septic tank and leaching field . 10. The leaching field generally consists of perforated pipe resting on gravel-filled beds that allow water to drain into the underlying soil.