in immediately. The speed of the winch should 

 be slow until the corer is joicked up. During 

 hoisting the piston supports the entire weight of 

 the corer. Do not increase the speed of the winch 

 until the corer is well clear of the bottom. 



Step 1. When the release mechanism comes to 

 deck working level bring in the trigger weight 

 and remove the release mechanism from the 

 wire. 



Step 2. Hoist the corer to deck working level, 

 and remove the weights (fig. Ij-11). 



Step 3. Bring the corer aboard keeping lines 

 on the core barrel to avoid excessive bending 

 (fig. 1^12). 



Figure L-11. 



The Hydro-PlasUc (PVC) corer at deck 

 working level. 



L-27 Removing, Logging, and Labeling the 

 Hydro-Plastic (PVC) Core. 



Step 1. Measure the length of sedimentation 

 on the outside of the coring tube. Retain this 

 measurement for step 5 below. 



L-12 



Figure L-12. 



Bringing the Hydro-Plastic (PVC) 

 piston corer aboard. 



Step 2. Remove the core cutter and core 

 catcher, and cap and seal the end of the coring 

 tube, using (PVC) cap and (PVC) solvent ce- 

 ment. Place any sediment on the cutter or 

 catcher in a sample jar. 



Step 3. Remove the hex-head bolts; slide the 

 (PVC) core tube off the weight stand assembly; 

 and sound the core tube with a rod to measure 

 the length of the core. 



Step 4. AVith a saw, make a cut through the 

 core tube above the core sample. Let the water 

 drain off slowly, then finish savnng off the ex- 

 cess core tube. Finally, cap and seal the core 

 tube. (This coring tube does not require a wax 

 coating.) 



Step 5. Next log the samples (coring tube and 

 sample jar) on the Oceanographic Log Sheet-M 

 according to instructions in paragraph L-39, 

 Oceanographic Log Sheet-M Bottom Sediment 

 Data. 



Step 6. Then label the samples according to 

 instructions given in paragraph 1^-40, Labeling 

 tlie Bottom Sediment Sample (s). 



Step 7. Pack, store, and ship cores in accord- 

 ance with instructions given in paragraph L-41, 

 Packing, Storing, and Shipping Bottom Sedi- 

 ment Samples. 



L-28 Maintenance of the (PVC) Hydro- 

 Plastic Corer. — The Hydro-Plastic corer re- 

 quires very- little maintenance. Spare parts are 

 contained in the storage case. Wash the weight 

 stand assembly, core catcher, and core cutter to 

 remove sediment, rinse with fresh wat«r, coat 

 lightly with oil, or wire brusli and paint with 

 red lead as necessary. 



L-29 Obtaining the Core. — All corers rigged 

 with a release mechanism, large or small, grav- 



