Leukocyte Esterase. Leukocyte esterase is an enzyme present in most white blood cells (WBCs). A few white blood cells are normally present in urine and usually give a negative chemical test result. When the number of WBCs in urine increases significantly, this screening test will become positive.
Land subsidence occurs when large amounts of groundwater have been withdrawn from certain types of rocks, such as fine-grained sediments. The rock compacts because the water is partly responsible for holding the ground up. When the water is withdrawn, the rocks falls in on itself.
If the pressure drops, the soil pressure increases and this leads to subsidence at the ground level. Since exploitation of the Slochteren (Netherlands) gas field started in the late 1960s the ground level over a 250 kmÂ² area has dropped by a current maximum of 30 cm.n Northern Japan, subsidence of 0.50 m (1.64 ft) was observed on the coast of the Pacific Ocean in Miyako, TÅhoku, while Rikuzentakata, Iwate measured 0.84 m (2.75 ft).