Step #2 With a knife, cut down 1 long side of each olive through to pit.
Step #3 Place olives in 1-gallon or 2-quart jars (glass or plastic; 2 gal.
Step #4 total volume) with noncorrodible lids, filling to within 1 inch of top.
Step #5 Fill jars to brim with water.
Step #6 Partially fill pint-size heavy plastic food bags (1 for each container) with water & seal; set a bag on top of olives in each jar to keep fruit submerged (water will overflow a little).
Step #7 Set jars away from sunlight.
Step #8 Once a day, drain water from the jars, holding olives back with your fingers.
Step #9 Rinse any foam or scum from jars & bags; refill the jars with cool water.
Step #10 (You may see a small amount of harmless bubbling in water; olives will also lose their brightness & leak color into the water.
Step #11 ) Repeat daily (it's fine if you miss a day now & then) until olives have a mild, pleasantly bitter taste, about 5 weeks total.
Step #12 Drain olives & pour salt equally over olives in jars.
Step #13 Pour vinegar & 7 c water into a 5- to 6-quart pan.
Step #14 Bring to a simmer over high heat.
Step #15 Pour hot liquid over olives to within 1/2 inch of jar rims.
Step #16 Let cool.
Step #17 Pour olive oil on top of liquid in each jar to completely cover surface, then secure lids.
Step #18 S$? S(?rate olives until vinegar flavor permeates them, 2 to 3 weeks.
Step #19 Taste; if desired, add 1/2 c more salt equally to jars & chill for 2 more days or up to 6 months.
Step #20 With time, olives become increasingly mellow.
Step #21 Once a month, check oil surface for scum or mold; skim off any.
Step #22 If olives smell fine & are firm, continue to store.
Step #23 If olives smell bad or become soft, discard.
Step #24 To serve, remove desired quantity of olives with a slotted spoon.
Step #25 To season, coat lightly with olive oil & add garlic or herbs to taste (see notes).