While High Altitude Pulmonary Edema (HAPE) and High Altitude Cerebral Edema (HACE) are indeed possible at the altitudes of White Mt. Research Center (WMRC), they are extremely rare. In fact, we have never had a documented case of HAPE or HACE at WMRC despite thousands of visitors, for example 200-400 on Open House days alone during our experience for the past decade. WMRC is in the Inyo National Forest which hosts thousands of visitors every year, including hundreds who climb to the summit of White Mt. that is several hundred meters higher than the WMRC Pace Lab and Barcroft facilities where we have the Open House (at 3,800m). Also note that people are free to drive to an even higher altitude on Pikes Peak (in Colorado) without any special requirements.
What is extremely common at the altitudes of WMRC is Acute Mountain Sickness (AMS). There is speculation that the headache with AMS is a subclinical case of HACE but this is not yet proven. In any case, AMS is (unfortunately) common but I repeat that we have not observed any cases of HACE. AMS is treated with analgesics and descent to lower altitude.
If HACE or HAPE should occur and are recognized quickly, the treatment is immediate descent and the conditions generally resolve. Fortunately, one can drive back to the low altitude hospital from WMRC within a couple of hours. The hospitals in Bishop and Mammoth Lakes are experienced at dealing with altitude illnesses and they treat a handfull of cases every year from the thousands of backpackers and climbers in the Sierra Nevada.
Travel to high altitude has risks and people need to be aware that hiking to the summit of White Mt. is not as simple as a 5 mile hike at sea level. Individuals traveling to any mountains need to take responsibility for their health and well-being. Travel to high altitude at WMRC is no different than travel to similar altitudes at a ski resort or hiking or climbing so please do not come to WMRC assuming that it is easier. The main difference at WMRC is that you can get there quickly by car, but you can also look forward to comfortable shelter from the elements. Note that the weather can turn severe even in the middle of summer, so please be prepared for anything in terms of weather, even if it is 100 deg F in the Owens Valley.
For more information about altitude illnesses, you are encouraged to check the following web site: