On May 6, 2011, at approximately 2:40 p.m., plaintiff Michael Ronan, a financial worker in his 50s, was driving his vehicle on westbound Olympic Boulevard in Los Angeles when an explosion occurred below Olympic Boulevard, emanating from an underground vault covered by an iron manhole. The explosion occurred just as Ronan drove over the manhole, causing the manhole and part of the vault casing to strike the rear of his vehicle and lift it off the road. Ronan claimed an injury to his lower back as a result of the accident. Ronan sued the owner of the underground vault, the city of Los Angeles, and the maintainer of the vault, the Los Angeles Department of Water and Power. Ronan alleged that the city and the Department of Water and Power negligently repaired and maintained the vault, creating a dangerous condition of public property. Ronan initially also sued the county of Los Angeles, Sempra Energy Company and Southern California Gas Company, but all three of those parties were dismissed by Ronan in the early stages of litigation. At trial, Ronan’s counsel contended that the poorly maintained vault resulted in an excessive accumulation of methane gas, which was ignited by a spark from poorly maintained electrical equipment in the vault. Thus, counsel argued that improper ventilation and inadequate compliance with methane mitigation regulations caused the explosion. The city and the Department of Water and Power claimed that a routine inspection of the subterranean vault, electrical equipment, and ventilation system was conducted six months prior to the vault explosion and failed to reveal any defects. It also claimed that the old subterranean vault in question was located within a naturally occurring “methane zone” in the city of Los Angeles and was in full compliance with all building code requirements in effect at the time of the creation, as well as was in full compliance with inspection policies and procedures. Counsel for the city and the Department of Water and Power contended that prior to the subject vault explosion, there were no similar incidents involving the vault or any others located within the methane zone. Thus, counsel argued that the vault explosion was caused by a spark that ignited a concentration of combustible methane gas and air due to the failure of normally reliable electrical equipment in the vault., Three days after the accident, Ronan was saw an emergency medicine doctor and later underwent MRIs of his lower back. He was ultimately diagnosed with a lumbar disc herniation with a broad annular tear superimposed upon a severe, pre-existing, degenerative lumbar canal stenosis condition. Ronan subsequently treated the injury conservatively with physical therapy and Pilates exercise for almost two years, as well as received three epidural injections. Despite his treatment, Ronan claimed he still experiences significant back pain and discomfort. He also claimed his condition interfered with his ability to work, as well as his activities of daily living. Ronan alleged that as a result, he was recommended to undergo decompression surgery for his lower back. Thus, he sought recovery of $33,037.42 in past medical costs (pre-Howell), approximately $100,000 in future medical costs for the decompression surgery, and an unspecified amount of damages for his past and future pain and suffering. Ronan did not make a claim for lost earnings. Defense counsel conducted extensive discovery, including an orthopedic evaluation and an analysis of forces by biomechanical and mechanical engineering experts. Thus, counsel determined that there was insufficient evidence to challenge Ronan’s allegations that he was asymptomatic with no pain complaints or medical treatment involving the spinal area within the five years before the subject incident date.