Please, please, please have the BART Long Term Metro Study (Bay Area Rapid Transit -- Hello!) scope include studying the cost/benefit and huge capacity increase that would come if BART closes the 21 mile Peninsula gap between Millbrae and the future terminus at Santa Clara/University.
Caltrain is at capacity and has proven 55,000 riders per day, with more Peninsula Corridor density in planning Only BART can address such high-density Smart Growth/Sustainable Communities Strategy vertical growth sprawl.
A key option to keep costs down, benefits up, is to replace the dangerous, deadly (11 dead this year, 23 since last year's start, and 199 since 1/1/1995) Peninsula Caltrain at-grade "kill train." BART has all the features of proposed Caltrain improvements, with electrified, grade-separated, savings by having only one Bay Area heavy rail administration, reduced Caltrain SF SoMa footprint and TBT docks for BART, no longer Caltrain, and, by being around the Bay (as per Perata's suggestion, 09-26-13), gain more transit efficiency for taxpayers and riders.
Enabled two-way BART Around the Bay greatly improves BART capacity and alternative routing of BART cars for incident recovery/avoidance. BART can share most Peninsula rail corridor ROW with HSR/Freight trains separate tracks (of course), with some, but limited need for more ROW acquisition/eminent domain, or, as part of the Peninsula Grand Blvd (El Camino Real) project corridor study, above or below ground level.
The Long Term BART Metro Study must consider the full loop of BART Around The Bay to save tax dollars in the long-term, increase TOD use, reduce congestion (Caltrain delays 100,000 cars each day--at least), reduce GHG and brake particulates, and increase pedestrian, cyclist and cross-traffic safety. The SF Bay Area needs one-seat heavy rail 24-hr high capacity, modern, electrified, grade-separated, safe rail, like many major US and EU cities. That means BART. After all, now even Santa Clara and San Mateo County residents are paying sales taxes for BART--but those in the 21 mile gap from Millbrae and Santa Clara are not getting their moneys worth!
Plan to Build BART Around The Bay, Now!